CS2351 Artificial Intelligence Important Questions for May June 2013 Exam

Anna University

Department of Computer Science Engineering

Semester : 6
Department : CSE
Subject Code : CS2351
Subject Name : Artificial Intelligence

Unit 1

1) Explain in detail about Agents and their types.

2) Explain in detail about uninformed search strategies with example.

3) Explain in detail about informed search strategies with example.

4) Explain in detail about Constraint satisfaction problem with example.

Unit 2

1. Explain in detail about forward & backward chaining algorithm with example.

2. Explain in detail about First order Logic & Inferences in First Order Logic with example.

3. Explain in detail about logical agents with example.

4. Explain in detail about Resolution & Resolution inference Rule with example.

5. Explain with at least 4 examples for PEAS cycle.

Unit 3

1. Explain about partial order planning with an example.

2. Explain about the different types of state space searches.

3. Explain about partial order planning algorithm.

4. Describe in detail about planning graphs.

5. Explain in detail about graph plan algorithm.

6. Explain in detail about conditional planning with an example.

7. Explain about replanning agent algorithm.

Unit 4

1. Explain in detail about Bayesian networks with an example.

2. Explain in detail about conditional probability.

3. Explain in detail about Markov Process with example.

4. Explain in detail about dynamic Bayesian networks.

5. Explain in detail about hidden markov models with example.

6. Explain in detail about inference in Bayesian network.

Unit 5

1. Explain the learning decision tree with algorithm with example.

2. (i).Explain the explanation based learning?

(ii).Explain how learning with complete data is achieved?

3. Discuss learning with hidden variables?

4. Explain all the statistical learning method with example.

5. Explain in detail about Reinforcement learning.

EE2355 Design of Electrical Machines Important Formulas and Expressions

Anna University

Department of Electrical and Electronics Engineering


Sixth Semester

EE2355 Design of Electrical Machines

(Regulation 2008)

Important Formulas and Expressions




EE2354 Microprocessors and Microcontroller Question Bank–2013 Edition

Anna University

Department of Electrical and Electronics Engineering

EE2354 Microprocessors and Microcontroller Question Bank






PART-A (2 marks)

1. What is the need for ALE signal in 8085 microprocessor?

2. How many machine cycles are needed to execute STA 1800?

3. What is the need for interfacing?

4. Compare memory mapped I/O and peripheral mapped I/O.

5. What is memory mapping?

6. What is interfacing?

7. What are Hardware interrupts?.

8. What are Software interrupts,

9. What is interrupt?

10. What is vectored and non vectored interrupts?

11. What is the need for timing diagram?

12. Define i) Instruction cycle

ii) Machine cycle

13. Define T-state and In which T-cycle the ALE signal is activated?

14. What is masking and why it is needed?

15. What are the different addressing modes of 8085?

PART-B (16 marks)

1. Describe the functional pin diagram of 8085. (16 Marks)

2. Describe the functional block diagram of 8085. (16 Marks)

3. Explain the 8085 interrupt system in detail. (16 Marks)

4. Explain various machine cycles supported by 8085. (16 Marks)

5. a) With suitable examples explain how I/O devices are connected using memory

mapped I/O and peripheral I/O. (10 Marks)

b) Design a microprocessor system to interface an 8K × 8 EPROM and

8K × 8 RAM. (6 Marks)

6. Draw timing diagrams for the following instruction with appropriate control and

status signal. Explain in brief. CALL 2000 (16 Marks)

7. Explain the addressing modes of 8085 with example. (16 Marks)

8. Explain the Different types of instruction in 8085. (16 Marks)

9. Write the program to count from 0 to 9 with a one second delay between each

count. At the count of 9, the counter should reset itself to 0 and repeat the

sequence continuously. Use register pair HL to set up the delay, and display

each count at one of the output ports. Assume clock frequency of the 8085

microprocessor as 1MHz. (16 Marks)



PART-A (2 marks)

1. List the operation modes of 8255

2. Define PPI.

Define USART.

3. What is key debouncing?

5. How a keyboard matrix is formed in keyboard interface using 8279?

6. Name any two type of ADC’S. .

7. What is the output modes used in 8279?

8. What are the modes used in keyboard modes?

9. What are the modes used in display modes?

10. How the RS -232C serial bus is interfaced to 1TL logic device?

PART-B (16 marks)

1. Explain any one of the modes of 8255 in detail. (16 Marks)

2. With neat block diagram explain PPI. (16 Marks)

3. i) Using model, write a program to communicate between two microprocessors

using 8255. (10 Marks)

ii) Show the control word format of 8255 and explain how each bit is

programmed. (6 Marks)

4. With neat block diagram explain the functions of 8251. (16 Marks)

5. i) Bring about the features of 8251. (6 Marks)

ii) Discuss how 8251 is used for serial communication of data. (6 Marks)

iii) Explain the advantages of using the USART chips in microprocessor based

systems. (4 Marks)

6. Design an interface circuit needed to connect DIP switch as an input device and

display the value of the key pressed using a 7 segment LED display. Using 8085

system, write a program to implement the same. (16 Marks)

7. i) Explain the advantages of using the keyboard and display controller chips in

microprocessor based system. (6 Marks)

ii) Write a program using RST 5.5 interrupt to get an input from keyboard and

display it on the display system. (6 Marks)

iii) Use RST 5.5 instead of RST 7.5 and change mask pattern accordingly.

(4 Marks)

8. With neat diagram explain the ADC interface to microprocessor. (16 Marks)

9. Explain in detail the RS 232C interface. (16 Marks)

10. i) How data is transformed by I2C Bus? Explain with timing diagram?

ii) What are different modes of I2C Bus? Explain in detail. (16 Marks)

11. Write a short note on GPIB. (16 Marks)



PART-A (2 marks)

1. Define pipelining?

2. Discuss the function of instruction queue in 8086?

3. What is the maximum memory size that can be addressed by 8086?

4. What is the function of the signal in 8086?

5.What are the predefined interrupts in 8086?.

6. What are the different flag available in status register of 8086?

7. List the various addressing modes present in 8086?

8. How single stepping can be done in 8086?

9. State the significance of LOCK signal in 8086?

10. What are the functions of bus interface unit (BIU) in 8086?

11. What is the clock frequency of 8086?

12. What are the two modes of operations present in 8086?

13. Explain the process control instructions

14. What is the purpose of segment registers in 8086?

15. What are the three classifications of 8086 interrupts?

16. What are the functions of status pins in 8086?

17. Give the instruction set of 8087?.

18. How do 8086 interrupts occur?

19. What are the 8086 interrupt types?

20. What is interrupt service routine?

21. What is interfacing?

22. What is meant by interrupt?

PART-B (16 marks)

1. Discuss the various addressing modes of 8086 microprocessor. (16 Marks)

2. Explain the internal block diagram of 8086. (16 Marks)

3. Draw the pin diagram of 8086 CPU with its control signals. (16 Marks)

4. Explain various data addressing modes of 8086 with the help of examples.

(16 Marks)

5. Explain the interrupt mechanism, types and priority of 8086 microprocessor.

(16 Marks)

6. Explain the instruction set of 8086 microprocessor. (16 Marks)

7. i) Describe what happens to the status flags as the sequence of instructions that

follows is executed in 8086 microprocessor architecture. (8 Marks)

Assume that flags ZF, SF, CF, AF, OF and PF are initially reset.

MOV AX, 1234H



ii) List out the shift instructions and rotate instructions in 8086. Give example for

each. (8 Marks)

8. ii) Draw the structure of 8086 flag register and explain the function of the flags

with examples. (8 Marks)

ii) Explain the functions of following 8086 signals.

1. HLDA 2. RQ/GTO 3. DEN 4. ALE (8 Marks)



PART-A (2 marks)

1. What is Microcontroller?

2. List the features of 8051 microcontroller.

3. Name the five interrupt sources of 8051?.

4. Explain the contents of the accumulator after the execution of the following

program segments:

5. Write a program to load accumulator A, DPH and DPL with 30H.

6. Write a program to subtract the contents of R1 of Bank0 from the contents of R0

of Bank2.

7. What is the difference between the Microprocessors and Microcontrollers?

8. Explain the functions of the pin PSEN of 8051.

9.Name the special functions register SP of 8051.

10.How the program memory is organized in 8051 based system?

PART-B (16 marks)

1. Describe the architecture of 8051 with neat diagram. (16 Marks)

2. i) Discuss the peripheral interface of 8051. (8 Marks)

ii) Explain the memory structure of 8051. (8 Marks)

3. Explain the interrupt structure of 8051 microcontroller Explain how interrupts are

prioritized. (16 Marks)

4. Explain the I/O port structure of 8051. (16 Marks)

5. Explain the different serial communication modes in 8051. (16 Marks)

6. Explain the function and operating modes of timer in 8051. (16 Marks)

7. Explain the functional pin diagram of 8051 Microcontroller. (16 Marks)



PART-A (2 marks)

1. Explain the operating mode0 of 8051 serial ports?

2. Explain the operating mode2 of 8051 serial ports?

3. Explain the mode3 of 8051 serial ports?

4.Write A program to perfom multiplication of 2 nos using 8051?

5. List the addressing modes of 8051?

6. Write about CALL statement in 8051?

7. Write about the jump statement?

8. Write program to load accumulator ,DPH,&DPL using 8051?

9. What is subroutine or procedure?

10. What is the function of SWAP?

11. What is Assembly Language Program?

12. What is debugging?


PART-B (16 marks)

1. i) Write 8051 ALP to read data from port I when negative edge triggered at INT0

and supply the data to port 2 by masking the upper 4 bits. (8 Marks)

ii) Write 8051 ALP to transmit ‘Hello World’ to PC at 9600 baud for external

crystal frequency of 11.0592MHz. (8 Marks)

2. With a neat circuit diagram explain how a 4 _ 4 keypad is interfaced with 8051

microcontroller and write 8051 ALP for keypad scanning. (16 Marks)

3. Draw the schematic for interfacing a stepper motor with 8051 microcontroller and

write 8051 ALP for changing speed and direction of motor. (16 Marks)

4. Draw the schematic for interfacing a servo motor with 8051 microcontroller and

write 8051 ALP for servo motor control. (16 Marks)

5. Explain the instruction set of 8051 microcontroller. (16 Marks)

6. i) Add the unsigned number found in 8051 microcontroller internal RAM locations

25h, 26h and 27h together and put the result in RAM locations 30h (MSB) and

31h (LSB). (6 Marks)

ii) List out the arithmetic operations of 8051 microcontroller with an example and

show how the flags are affected for each operation. (10 Marks)

7. i) Write the Analog to Digital conversion program in 8051 microcontroller to

convert analog data into digital. Digitalize the input for every 100μs and store the

1000 values in external RAM location 4000b to 43E7h. (8 Marks)

ii) Explain the JUMP instructions present in 8051 microcontroller with a

mnemonic code and its operation for each. (8 Marks)



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CE2253 Applied Hydraulic Engineering Question Bank for May / June 2013 Exam

Anna University




CE2253 Applied Hydraulic Engineering


PART - A (2 Marks)

1. Distinguish between open channel flow and conduit flow.

2. What are wide channels?

(AUC Nov/Dec 2010) (AUC Nov/Dec 2010)

3. Define open channel flow ? (AUC Apr/May 2010)

4. Compute the hydraulic mean depth of a small channel 1m wide, 0.5m deep with water flowing at m/s. (AUC Apr/May 2010)

5. Define Specific energy of flowing liquid. (AUC Apr/May 2011)

6. How do you find the critical depth of flowing water? (AUC Apr/May 2011)

7. What are the different types of flow in open channel? (AUC Apr/May 2012)

8. Define Specific energy. (AUC Apr/May 2012)

9. Write Renold’s number for different states of flow in an open channel.

10. “Critical flow section is an excellent control section” – Justify the statement.

11. In an open channel of rectangular section if the minimum specific energy is 6 m, what is its critical depth?

12. A rectangular channel carries a flow of 4m3/s/m, what is the critical depth?

13. What are the different types of varied flows?

14. What is an isovel?

15. Define hydraulic depth(D) of an open channel flow.

PART –B (16 Marks)

1. How do you classify open channels? Explain in detail. Also explain the velocity distribution in open channel. (AUC Nov/Dec 2010)

2. Write short notes on the following:

(i) Critical flow and its computations

(ii) Channel Transition (AUC Nov/Dec 2010)

3. (i) Define specific energy. How would you express the specific energy for a wide rectangular channel with depth of flow ‘D’ and velocity of flow ‘V’? Draw the typical specific energy diagram and explain its features.

(ii) Calculate the specific energy, critical depth and velocity for the flow of 10m3/s in a cement lined rectangular channel 0.5m wide with 2m depth of water. Is the given flow subcritical or supercritical? (AUC Apr/May 2010)

4. (i) Define Froude number FR. Describe the flow for FR = , FR < and FR >1. Represent a discharge versus depth curve for a constant specific energy and explain its features.

(ii) A trapezoidal channel has a bottom width of 6.1m and side slopes of 2H: 1V. When the depth of flow is 1.07 m, the flow is 10.47 m3/s? What is the specific energy of flow? Is the flow tranquil or rapid? (AUC Apr/May 2010)

5. A trapezoidal channel with side slopes of 2 horizontal: 3 vertical has to carry 20 m3/sec.

Find the slope of the channel when the bottom width of the channel is m and the depth of the water is 3 m. Take Manning’s n = 0.03. (AUC Apr/May 2011)

6. Calculate the specific energy of 12m3/sec of water flowing with a velocity of 1.5 m/s in a rectangular channel 7.5m wide. Find the depth of water in the channel when the specific energy would be minimum. What would be the value of critical velocity as well as minimum specific energy? (AUC Apr/May 2011)

7. (i) How are the flows classified under specific energy concepts?

(ii) A 8m wide channel conveys 15 cumecs of water at a depth of 1.2m. Determine

(1) Specific Energy of the flowing water (2) Critical depth, critical velocity and minimum specific energy (3) Froude number and state whether the flow is subcritical or supercritical. (AUC Apr/May 2012)

8. (i) Explain the salient features of Specific Energy curve.

(ii) Determine the critical depth for a specific energy of 1.5 m in the following channels

(1) Rectangular channel

(2) Triangular channel

(3) Trapezoidal channel. (AUC Apr/May 2012)

9. (i) Find the critical depth for a specific energy of 1.5 m in: (1) Rectangular channel of bottom width 2m (2)Triangular channel of side slope 1:1.5

(3)Trapezoidal channel of bottom width 2m and side slope 1:1? (ii) What are the different types and states of flow in open channel?

10. (i) Prove that for critical flow specific is minimum.

(ii) Calculate the width of a rectangular channel required to carry a discharge 15m3/s as critical flow at a depth of 1.2m.

PART - A (2 Marks)

1. Mention the significance of Manning’s formula. (AUC Nov/Dec 2010)

2. What are the essential conditions for most economical section? (AUC Nov/Dec 2010)

3. Write down the Chezy’s formula for determining velocity of flow in an open channel. (AUC Apr/May 2010)

4. Show that the maximization of discharge requires maximization of the wetted perimeter of the channel for a given area of flow. (AUC Apr/May 2010)

5. Distinguish between uniform and non-uniform. (AUC Apr/May 2011)

6. Define the Froude Number. What is its significance? (AUC Apr/May 2011)

7. Distinguish between normal depth and critical depth. (AUC Apr/May 2012)

8. What are the conditions for the most economical triangular channel section?

(AUC Apr/May 2012)

9. Define ‘conveyance’ of an open channel.

10. Why are best hydraulic sections in open channel flow referred as most economical sections?

11. A river with a lined banks has a Manning’s n = 0.014, and Chezy’ C = 55, What is its hydraulic radius?

12. What is equivalent roughness or composite roughness of an open channel?

13. What are the geometric conditions for a triangular channel to be most economic?

14. Define normal discharge and normal slope.

15. Define uniform flow.

PART –B (16 Marks)

1. A channel is designed to carry a discharge of 20 m3/s with Manning’s n = 0.015 and bed slope of 1 in 1000 (for trapezoidal channel side slope M = 1√3). Find the channel dimensions of the most efficient section if the channel is (i) trapezoidal

(ii) rectangular. (AUC Nov/Dec 2010)

2. Explain the computation of uniform flow using Manning’s and Chezy’s method. (AUC Nov/Dec 2010)

3. (i) A V – shaped open channel of included angle 90º conveys a discharge of 0.05 m3/s when the depth of flow at the center is 0.225 m. Assuming that C = 50 m1/2/s in the Chezy’s equation, calculate the slope of the channel.

(ii) Calculate the dimensions of the rectangular cross-section of an open channel which requires minimum area to convey 10 m3/s. The slope being in 1500. Take the Manning’s ‘N’ as 0.013. (AUC Apr/May 2010)

4. Derive the expressions for the most economical depths of flow of water in terms of the diameter of the channel of circular cross-section:

(i) For maximum velocity and

(ii) For maximum discharge. (AUC Apr/May 2010)

5. (i) Derive the Chezy’s equation for steady uniform flow.

(ii) Derive the relationship for most economical trapezoidal channel. (AUC Apr/May 2011)

6. A power canal of trapezoidal section has to be excavated through hard clay at the least cost. Determine the dimensions of the channel given, discharge equal to 14 m3/s, bed slope 1/2500, Manning’s n = 0.02. (AUC Apr/May 2011)

7. (i) Show that the hydraulic radius is half the flow depth for the most economical trapezoidal channel section.

(ii) Determine the most economical section of rectangular channel carrying water at the rate of 0.6 cumecs. The bed slope is 1 in 2000. Assume Chezy’s constant C = 50. (AUC Apr/May 2012)

8. (i) How do you determine velocity of flow in open channel?

(ii)The bed width of a trapezoidal channel section is 40 m and the side slope is 2 horizontal to 1 vertical. The discharge in the canal is 60 cumecs. The Manning’s ‘n’ is 0.015 and the bed slope is 1 in 5000. Determine the normal depth. (AUC Apr/May 2012)

9. Derive the geometrical properties of a most economical triangular channel section.

10. (i) A rectangular channel of width 15m has abed slope of 0.00075 and Manning’s n = 0.016. Compute the normal depth to carry a discharge of 50m3/s?

(ii)Explain the graphical method of determination of normal depth for a trapezoidal channel.


PART - A (2 Marks)

1. What are the assumptions made in dynamic equation for gradually varied flow?

(AUC Nov/Dec 2010)

2. What is mean by back water curve? (AUC Nov/Dec 2010)

3. What is a draw down curve? (AUC Apr/May 2010)

4. Indicate the usefulness of hydraulic jump. (AUC Apr/May 2010)

5. What is the energy loss in a hydraulic jump? (AUC Apr/May 2011)

6. How is back water curve formed? (AUC Apr/May 2011)

7. Write down the dynamic equation of gradually varied flow. (AUC Apr/May 2012)

8. Distinguish between positive and negative surges. (AUC Apr/May 2012)

9. Differentiate between draw down and back water curves.

10. Define sequent depth.

11. What is the nature of slope of the channel if critical depth line occurs above normal depth line?

12. What is the state of flow after formation of a hydraulic jump?

13. What is the control section of an open channel flow?

14. What are the assumptions in varied flow?

15. Write two methods used for flow profile determination.

PART – B (16 Marks)

1. How do you classify surface profiles? Briefly explain the various salient features of various profiles. Also write a note on hydraulic jump. (AUC Nov/Dec 2010)

2. A 50 m long laboratory flume has a rectangular section with a width of 2m and ends in a free overall. The channel is made of glass and the bed drops by 5 cm in the entire length. At a certain discharge, it was seen that the depth near the channel entrance was more or less constant at 0.5 m. Use the direct step method to obtain the length of profile. Use two equal depth increments. (AUC Nov/Dec 2010)

3. (i) In a given channel, Yo and Yc are two fixed depths if Q, N and So are fixed. Also, there are three possible relation between Yo and Yc. Further, there are two cases where You does not exist. Based on these, how the channels are classified?

(ii)A river 100 m wide and 3m deep has an average bed slope of 0.0005. Estimate the length of the GVF profile produced by a low weir which raises the water surface just upstream of it by 1.5 m. Assume N = 0.035. Use direct step method with three steps. (AUC Apr/May 2010)

4. (i) Explain the classification of hydraulic jumps.

(ii) A spillway discharges a flood flow at a rate of 7.75 m3/s per metre width. At the downstream horizontal apron the depth of flow was found to be 0.5 m. What tail water depth is needed to form a hydraulic jump? If a jump is formed, find its type, length, head loss and energy loss as a percentage of the initial energy. (AUC Apr/May 2010)

5. In a rectangular channel of 0.5 m width, a hydraulic jump occurs at a point where depth of water flow is 0.15 m and Froude number is 0.5. Determine

(i) The specific energy

(ii) The critical and subsequent depths

(iii) Loss of head and

(iv) Energy dissipated. (AUC Apr/May 2011)

6. A river of 45 m wide has a normal depth of flow of 3 m and an average bed slope of in 10,000.A weir is build across the river raising the water surface level at the weir site to 5 m above the bottom of the river. Assuming that the back water curve is an arc of circle; calculate the approximate length of the curve. Manning’s n = 0.025.(AUC Apr/May 2011)

7. (i) What are the assumptions made in the analysis of gradually varied flow?

(ii)The bed width of a rectangular channel is 24 m and the depth of flow is 6m. The discharge in the canal is 86 cumecs. The bed slope of the channel is 1 in 4000. Assume Chezy’s constant C = 60. Determine the slope of the free water surface. (AUC Apr/May 2012)

8. (i)What are the conditions for the formation of hydraulic jump?

(ii)In a rectangular channel of bed width 0.5 m, a hydraulic jump occurs at a point where depth of flow is 0.15 m and Froude’s number is 2.5. Determine

(1) The specific energy (2) The critical depth (3) The subsequent depths (4) Loss of head (5) Energy dissipated. (AUC Apr/May 2012)

9. (i) A rectangular channel carries a flow with a velocity of 0.65m/s and depth of 1.4m. If the discharge is abruptly increased three fold by sudden lifting of a gate on the upstream side, estimate the velocity and height of the resulting surge?

(ii)With neat diagrams explain different types of channel transitions.

10. (i)Write the gradually varied flow equation in an open channel flow. Deduce the equation for a wide rectangular channel using Manning’s and chezy’s equation.

(ii)Explain with a neat diagram the surges produced when (i) a sluice gate is suddenly raised (ii)sluice gate is suddenly lowered.

PART - A (2 Marks)

1. Define Priming. (AUC Nov/Dec 2010)

2. What is the significance of air vessel? (AUC Nov/Dec 2010)

3. Why is the theoretical suction height of a pump limited? (AUC Apr/May 2010)

4. Define negative slip. How it occurs? (AUC Apr/May 2010)

5. What are the differences between jet pump and submersible pump?

(AUC Apr/May 2011)

6. Draw an ideal indicator diagram. (AUC Apr/May 2011)

7. Define specific speed of a pump. (AUC Apr/May 2012)

8. Draw the indicator diagram for a single acting reciprocating pump.

2012)Why submersible pump named so?

9. Differentiate between a rotodynamic pump and rotary pump.

10. What is the function of foot valve in a pump?

(AUC Apr/May

11. What is the condition for finding the minimum starting speed of centrifugal pump?

12. Name two rotary pumps.

13. What are multistage pumps?

14. For a single acting reciprocating pump what are the angles at which there is no flow into and out of the air vessel?

PART –B (16 Marks)

1. A single acting reciprocating pump having a cylinder diameter of 150 mm and stroke of 300 mm is used to raise the water through a height of 20 m. Its crank rotates at 60 rpm. Find the theoretical power required to run the pump and the theoretical discharge. If actual discharge is 5 lit/s find the percentage of slip. If delivery pipe is 100 mm in diameter and is 15 m long, find the acceleration head at the beginning of the stroke. (AUC Nov/Dec 2010)

2. Discuss in detail the working of Centrifugal pump. Also write a note on working of jet pump. (AUC Nov/Dec 2010)

3. (i) With the help of neat sketches, explain the features of a volute type and a diffusion type centrifugal pump

(ii)A centrifugal pump delivers salt water against a head of 15 m at a speed of 100 rpm. The vanes are curved backward at 30º with the periphery. Obtain the discharge for an impeller diameter of 30 cm and outlet width of 5 cm at a manometric efficiency of 90%.

(AUC Apr/May 2010)

4. (i) Draw the indicator diagram of a reciprocating pump for the following cases : (1) Without air vessels on both suction and delivery sides.

(2) With air vessel only on suction side.

(ii) For a hydraulic machine installed between A and B, the following data is available: At A At B

Diameter 20cm 30cm Elevation 105m 100m Pressure 100 kPa 200 kPa

The direction of flow is from A to B and the discharge is 200 litres per second. Is the machine a pump or a turbine? (AUC Apr/May 2010)

5. The impeller of a centrifugal pump having external and internal diameters 500 mm and

250 mm respectively, width at outlet 50 mm and running at 1200rpm. Works against a head of 48 m. The velocity of flow through the impeller is constant and equal to 3 m/s. The vanes are set back at an angle of 40º at outlet. Determine

(i) Inlet Vane angle

(ii) Work –done by the impeller and Manometric efficiency. (AUC Apr/May 2011)

6. A three throw pump has cylinders of 250 mm diameter and stroke of 500 mm each. The pump is required to deliver 0.1 m3/sec at a head of 100 m. Friction losses are estimated to be m in the suction pipe and 19 m in delivery pipe. Velocity of water in delivery pipe is m/s, overall efficiency is 85% and the slip is 3% Determine

(i) Speed of the pump and

(ii) Power required for running the pump. (AUC Apr/May 2011)

7. (i) Define

(1) Manometric efficiency (2) Volumetric efficiency (3) Mechanical efficiency

(4) Overall Efficiency of Centrifugal pump.

(ii) The impeller of a centrifugal pump has an external diameter of 450 mm and internal diameter of 200 mm. The speed of the pump is 1440 rpm. Assuming a constant radial flow through the impeller at 2.5 m/s and that the vanes at exit are set back at an angle of

25º, Determine:

(1) The inlet vane angle

(2) The angle, the absolute velocity of water at exit makes with the tangent and

(3) The work done per unit weight. (AUC Apr/May 2012)

8. (i) Explain the working principle of double acting reciprocating pump with a neat sketch. (ii) Length of 350 mm. The speed of the pump is 60 rpm and the discharge is

0.02cumecs of water. Determine (1) The theoretical discharge (2) Coefficient of discharge

(3) Percentage slip. (AUC Apr/May 2012)

9. (i) Compare and contrast Centrifugal pump and reciprocating pump.

(ii)The cross sectional area of a plunger of reciprocating pump equals 1.5 times that of a delivery pipe. The delivery pipe is 60m long and it rises upward at a slope of 1 in 6. If the plunger has an acceleration of 2.4m/s2 at the end of the stroke and separation pressure is 2.5m of water find whether separation will take place.

10. (i)Explain the different types of Reciprocating pumps? (ii)Differentiate pumps and turbines.


PART - A (2 Marks)

1. Distinguish between impulse and reaction turbines. (AUC Nov/Dec 2010)

2. What is cavitation? How do you prevent cavitation? (AUC Nov/Dec 2010)

3. Classify Pelton turbine according to

(a) The direction of flow through the turbine runner

(b) The action of water on turbine blades. (AUC Apr/May 2010)

4. Define specific speed of a turbine. (AUC Apr/May 2010)

5. What is the use of draft tube? (AUC Apr/May 2011)

6. Define the specific speed of a turbine. (AUC Apr/May 2011)

7. How would you classify turbines based on the direction of flow in the runner?

(AUC Apr/May 2012)

8. Draw typical velocity triangles for inlet and outlet of Pelton wheel.

(AUC Apr/May 2012)

PART –B (16 Marks)

1. A Pelton wheel operates with a jet of jet of 150 mm diameter under the head of 500 m, its mean runner diameter is 0.25 m and it rates with a speed of 375 rpm. The angle of bucket tip at outlet as 15º, coefficient of velocity is 0.98, mechanical losses equal to 3% of power supplied and the reduction in relative velocity of water while passing through bucket is 15%. Find (i) the force of jet on the bucket (ii) the power developed (iii) bucket efficiency and (iv) overall efficiency. (AUC Nov/Dec 2010)

2. Derive the equation for power and work done for the impact of jets on moving curved vanes. Explain the classification of turbines. (AUC Nov/Dec 2010)

3. (i) Classify the turbines based on :

(1) Action of water on turbine blades. (2) Head on turbine.

(3) Direction of flow through turbine runner. (4) Specific speed.

(5) Disposition of turbines shaft.

(ii) A Pelton turbine is required to develop 9000 kW when working under a head of 300 m. The runner may rotate at 500 rpm. Assuming the jet ratio as 10, speed ratio as 0.46 and overall efficiency as 85%, determine the following:

(1) Quantity of water required

(2) Diameter of the wheel

(3) Number of jets

(4) Number of buckets. (AUC Apr/May 2010)

4. (i) Draw the characteristics curves of turbines and explain.

(ii) An inward flow reaction turbine operates under a head of 25 m running at 200 rpm. The peripheral velocity at the runner is 20 m/s and the radial velocity at the runner exit is

5 m/s. If the hydraulic losses are 20% of the available head, calculate: (1) The guide-vane exit angle

(2) The runner-vane angle

(3) The runner diameter

(4) The specific speed, if the width of the runner at the periphery is 30 cm and

(5) The power produced by the turbine. (AUC Apr/May 2010)

5. A Pelton wheel generates 8000 kW under a net head of 130 m at a speed of 200 rpm.

Assuming the coefficient of velocity for the nozzle 0.98, hydraulic efficiency 87%, speed ratio 0.46 and jet diameter to wheel diameter ratio 1/9, Determine,

(i) Discharge required

(ii) Diameter of the wheel

(iii) Diameter and number of jets required and

(iv) Specific speed of the turbine. Take Mechanical efficiency is 75%.

(AUC Apr/May 2011)

6. In an inward flow reaction turbine, head on turbine is 32 m. The external an internal diameters are 0.44 m and 0.72 m respectively. The velocity of flow through the runner is constant and equal to 3 m/s. The guide blade angle is 10º and runner vanes are rigid at inlet. If the discharge at outlet is radial, determine

(i) The speed of the turbine

(ii) The vane angle at outlet of the runner and

(iii) Hydraulic efficiency. (AUC Apr/May 2011)

7. (i) Distinguish between impulse and reaction turbines.

(iii) A Pelton wheel is required to develop 8825 kW when working under the head of 300 m. The speed of the pelton wheel is 540 rpm. The coefficient of velocity is 0.98 and the speed ratio is 0.46. Assuming jet ratio as 10 and overall efficiency as 84%. Determine :

(1) The number of jets

(2) The diameter of the wheel

(3) The quantity of water required (AUC Apr/May 2012)

8. (i) What are the various types of draft tube?

(ii) A Francis turbine is to be designed to develop 360 kW under a head of 70 m and a speed of 750 rpm. The ratio of width of runner to diameter of runner ‘n’ is 0.1. The inner diameter of the runner is half the outer diameter. The flow ratio is 0.15. The hydraulic efficiency is 95% and the mechanical efficiency is 84%. Four percent of the circumferential area of runner is to be occupied by the thickness of the vanes. The velocity of flow is constant and the discharge is radial at exit.


(1) The diameter of the wheel

(2) The quantity of water supplied

(3) The guide vane angle at inlet and

(4) Runner vane angles at inlet and exit. (AUC Apr/May 2012)

CE2351 Structural Analysis–II Two Marks with Answers for May June 2013 Exam

Anna University



Questions & Answers

(Two Marks)



1. What is meant by indeterminate structures?

Structures that do not satisfy the conditions of equilibrium are called indeterminate structure. These structures cannot be solved by ordinary analysis techniques.

2. What are the conditions of equilibrium?

The three conditions of equilibrium are the sum of horizontal forces, vertical forces and moments at any joint should be equal to zero.

3. Differentiate between determinate and indeterminate structures.Determinate structures can be solving using conditions of equilibrium alone ( H = 0; V = 0; M = 0). No other conditions are required.

Indeterminate structures cannot be solved using conditions of equilibrium because ( H ≠ 0; V ≠0; M ≠ 0). Additional conditions are required for solving such structures.


4. Define degree of indeterminacy.

The excess number of reactions that make a structure indeterminate is called degree of

Indeterminacy. Indeterminacy is also called degree of redundancy.

Indeterminacy consists of internal and external indeterminacies.

It is denoted by the symbol ‘i’

Degree of redundancy (i) = I.I. + E.I.

Where I.I. = internal indeterminacy and E.I. = external indeterminacy.


5. Define internal and external indeterminacies.

Internal indeterminacy (I.I.) is the excess no of internal forces present in a member that make a structure indeterminate.

External indeterminacy (E.I.) is excess no of external reactions in the member that make the structure indeterminate.

Indeterminacy = I.I. + E.I.

E.I. = r – e; where r = no of support reactions and e = equilibrium conditions

I.I. = i – EI

e = 3 (plane frames) and e = 6 (space frames)


6. Write the formulae for degree of indeterminacy for:

(a) Two dimensional pinjointed truss (2D Truss)

i = (m+r) – 2j where m = no of members

r = no of reactions; j = no of joints

(b) Two dimensional rigid frames/plane rigid frames (2D Frames)

i = (3m+r) – 3j where m = no of members

r = no of reactions; j = no of joints

(c) Three dimensional space truss (3D Truss)

i = (m+r) – 3j where m = no of members

r = no of reactions; j = no of joints

(d) Three dimensional space frames (3D Frame)

i = (6m+r) – 6j where m = no of members

r = no of reactions; j = no of joints


7. Determine the degree of indeterminacy for the following 2D truss.

i = (m+r) - 2j

Where, m = 19; r = 4; j = 10; e = 3 i = (19+4) – 2 x 10 = 3

External indeterminacy E.I. = r – e = 4 – 3 = 1

Internal indeterminacy I.I. = i – E.I. = 3 -1 = 2

8. Determine the total, internal and external degree of indeterminacy for the plane rigid frame below.

i = (3m + r) – 3j

Where, m = 7; r = 4; j = 6; e = 3 i = (3 x 7 + 4) – (3 x 6) = 7

External indeterminacy E.I. = r – e = 4 – 3 = 1

Internal indeterminacy I.I. = i – EI = 7 -1 = 6

9. Determine i, EI, II for the given plane truss.

i = (m + r) – 2j

Where, m = 3; r = 4; j = 3; e = 3 i = (3 + 4) – (2 x 3) = 1

External indeterminacy EI = r – e = 4 – 3 = 1

Internal indeterminacy II = i – EI = 1 -1 = 0

10. Find the indeterminacy for the beams given below.

For beams degree of indeterminacy is given by i = r – e

(a) clip_image006

i = r – e where, r = no of reactions, e = no of equilibrium conditions r = 4 and e = 3

i = 4 – 3 = 1

(b) clip_image008

i = r – e where, r = no of reactions, e = no of equilibrium conditions r = 5 and e = 3

i = 5 – 3 = 2


11. Find the indeterminacy for the given rigid plane frame.

i = (3m + r) – 3j

Where, m = 3; r = 4; j = 4

i = (3 x 3 + 4) – (3 x 4) = 1

External indeterminacy EI = r – e = 4 – 3 = 1

Internal indeterminacy II = i – EI = 1 - 1 = 0

12. Find the indeterminacy of the space rigid frame.

i = (6m + r) – 6j

Where, m = 8; r = 24 (i. e. 6 per support x 4)

j = 8; e = 6

i = (6 x 8 + 24) – (6 x 8) = 24


External indeterminacy EI = r – e = 24 – 6 = 18

Internal indeterminacy II = i – EI = 24 -18 = 6

13. Find the indeterminacy for the given space truss.

i = m + r – 3j


Where m = 3

r = 18 (i. e. 6 reactions per support x 3)

j = 4

i = (3 + 18) – (3 x 4) = 9

External indeterminacy EI = r – e = 18 – 6 = 12

Internal indeterminacy II = i – EI = 9 -12 = –3

14. What are the different methods of analysis of indeterminate structures?

The various methods adopted for the analysis of indeterminate structures include:

v Flexibility matrix method

v Stiffness matrix method

v Finite Element method


15. Briefly mention the two types of matrix methods of analysis of indeterminate structures.

The two matrix methods of analysis of indeterminate structures are: (i) Flexibility matrix method:

This method is also called the force method in which the forces in the structure are treated as unknowns. The no of equations involved is equal to the degree of static indeterminacy of the structure.

(ii) Stiffness matrix method:

This is also called the displacement method in which the displacements that occur in the structure are treated as unknowns. The no of displacements involved is equal to the no of degrees of freedom of the structure.


16. Define a primary structure.

A structure formed by the removing the excess or redundant restraints from an indeterminate structure making it statically determinate is called primary structure. This is required for solving indeterminate structures by flexibility matrix method.


17. Define kinematic indeterminacy (Dk) or Degree of Freedom (DOF)

Degree of freedom is defined as the least no of independent displacements required to define the deformed shape of a structure.

There are two types of DOF: (a) Nodal type DOF and (b) Joint type DOF.


18. Briefly explain the two types of DOF.

(a) Nodal type DOF – This includes the DOF at the point of application of concentrated load or moment, at a section where moment of inertia changes, hinge support, roller support and junction of two or more members.

(b) Joint type DOF – This includes the DOF at the point where moment of inertia changes, hinge and roller support, and junction of two or more members.


19. For the truss shown below, what is the DOF?

Pin-jointed plane frame/truss

DOF / Dk = 2j – r

Where, r = no of reactions; j = no of joints


20. Define compatibility in force method of analysis .

Compatibility is defined as the continuity condition on the displacements of the structure after external loads are applied to the structure.


21. Define the Force Transformation Matrix.

The connectivity matrix which relates the internal forces Q and the external forces R is known as the force transformation matrix. Writing it in a matrix form,

{Q} = [b] {R}

Where, Q = member force matrix/vector; b = force transformation matrix

R = external force/load matrix/ vector


22. What are the requirements to be satisfied while analyzing a structure?

The three conditions to be satisfied are: (i) Equilibrium condition

(ii) Compatibility condition

(iii) Force displacement condition


23. Define flexibility influence coefficient (fij)

Flexibility influence coefficient (fij) is defined as the displacement at joint ‘i’ due to a unit load at

joint ‘j’, while a l other joints are not load.


24. Write the element flexibility matrix (f) for a truss member & for a beam element.

The element flexibility matrix (f) for a truss member is given by


The element flexibility matrix (f) for a beam element is given by





1. What are the basic unknowns in stiffness matrix method?

In the stiffness matrix method nodal displacements are treated as the basic unknowns for the solution of indeterminate structures.


2. Define stiffness coefficient kij.

Stiffness coefficient ‘kij’ is defined as the force developed at joint ‘i’ due to unit displacement at

joint ‘j’ while a l other joints are fixed.


3. What is the basic aim of the stiffness method?

The aim of the stiffness method is to evaluate the values of generalized coordinates ‘r’ knowing

the structure stiffness matrix ‘k’ and nodal loads ‘R’ through the structure equilibrium equation.

{R} = [K] {r}


4. What is the displacement transformation matrix?

The connectivity matrix which relates the internal displacement ‘q’ and the external displacement

‘r’ is known as the displacement transformation matrix ‘a’.

{q} = [a] {r}


5. How are the basic equations of stiffness matrix obtained?

The basic equations of stiffness matrix are obtained as: Equilibrium forces

Compatibility of displacements

Force displacement relationships


6. What is the equilibrium condition used in the stiffness method?

The external loads and the internal member forces must be in equilibrium at the nodal points.


7. What is meant by generalized coordinates?

For specifying a configuration of a system, a certain minimum no of independent coordinates are necessary. The least no of independent coordinates that are needed to specify the configuration is known as generalized coordinates.


8. What is the compatibility condition used in the flexibility method?

The deformed elements fit together at nodal points.


9. Write about the force displacement relationship.

The relationship of each element must satisfy the stress-strain relationship of the element material.


10. Write the element stiffness for a truss element.

The element stiffness matrix for a truss element is given by



11. Write the element stiffness matrix for a beam ele ment.

The element stiffness matrix for a beam element is given by



12. Compare flexibility method and stiffness method.

Flex ibility matrix method:

The redundant forces are treated as basic unknowns.

The number of equations involved is equal to the degree of static indeterminacy of the structure.

The method is the generalization of consistent deformation method. Different procedures are used for determinate and indeterminate structures

Stiffness matrix method:

The joint displacements are treated as basic unknowns

The number of displacements involved is equal to the no of degrees of freedom of the


The method is the generalization of the slope deflection method.

The same procedure is used for both determinate and indeterminate structures.


13. Is it possible to develop the flexibility matrix for an unstable structure?

In order to develop the flexibility matrix for a structure, it has to be stable and determinate.


14. What is the relation between flexibility and stiffness matrix?

The element stiffness matrix ‘k’ is the inverse of the element flexibility matrix ‘f’ and is given by f = 1/k or k = 1/f.


15. What are the types of structures that can be solved using stiffness matrix method?

Structures such as simply supported, fixed beams and portal frames can be solved using stiffness matrix method.


16. Give the formula for the size of the Global stiffness matrix.

The size of the global stiffness matrix (GSM) = No: of nodes x Degrees of freedom per node.


17. List the properties of the stiffness matrix

The properties of the stiffness matrix are: It is a symmetric matrix

The sum of elements in any column must be equal to zero.

It is an unstable element therefore the determinant is equal to zero.


18. Why is the stiffness matrix method also called equilibrium method or displacement method?

Stiffness method is based on the superposition of displacements and hence is also known as the displacement method. And since it leads to the equilibrium equations the method is also known as equilibrium method.


19. If the flexibility matrix is given as


Write the corresponding stiffness matrix.

Stiffness matrix = 1 / (Flexibility matrix)

i.e. [K] = [F]-1


20. Write then stiffness matrix for a 2 D beam element.

The stiffness matrix for a 2 D beam element is given by




1. What is meant by Finite element method?

Finite element method (FEM) is a numerical technique for solving boundary value problems in which a large domain is divided into smaller pieces or elements. The solution is determined by assuming certain polynomials. The small pieces are called finite element and the polynomials are called shape functions.


2. List out the advantages of FEM.

Ø Since the properties of each element are evaluated separately different material properties can be incorporated for each element.

Ø There is no restriction in the shape of the medium.

Ø Any type of boundary condition can be adopted.


3. List out the disadvantages of FEM.

Ø The computational cost is high.

Ø The solution is approximate and several checks are required.


4. Mention the various coordinates in FEM.

Ø Local or element coordinates

Ø Natural coordinates

Ø Simple natural coordinates

Ø Area coordinates or Triangular coordinates

Ø Generalized coordinates


5. What are the basic steps in FEM?

Ø Discretization of the structure

Ø Selection of suitable displacement function

Ø Finding the element properties

Ø Assembling the element properties

Ø Applying the boundary conditions

Ø Solving the system of equations

Ø Computing additional results


6. What is meant by discretization?

Discretization is the process of subdividing the given body into a number of elements which results in a system of equivalent finite elements.


7. What are the factors governing the selection of finite elements?

Ø The geometry of the body

Ø The number of independent space coordinates


8. Define displacement function.

Displacement function is defined as simple functions which are assumed to approximate the displacements for each element. They may assume in the form of polynomials, or trigonometrical functions.


9. Briefly explain a few terminology used in FEM.

The various terms used in FEM are explained below.

Finite element: Small elements used for subdividing the given domain to be analysed are called finite elements. These elements may be 1D, 2D or 3D elements depending on the type of structure.

Nodes and nodal points: The intersection of the different sides of elements are called nodes. Nodes are of two types – external nodes and internal nodes.

External nodes – The nodal point connecting adjacent elements.

Internal nodes – The extra nodes used to increase the accuracy of solution.

Nodal lines: The interface between elements are called nodal lines.

Continuum: The domain in which matter exists at every point is called a continuum. It can be assumed as having infinite number of connected particles.

Primary unk nowns: The main unknowns involved in the formulation of the element properties are known as primary unknowns.

Secondary unk nowns: These unknowns are derived from primary unknowns are known as secondary unknowns. In displacement formulations, displacements are treated as primary unknowns and stress, strain, moments and shear force are treated as secondary unknowns.

10. What are different types of elements used in FEM?

The various elements used in FEM are classified as: One dimensional elements (1D elements) Two dimensional elements (2D elements) Three dimensional elements (3D elements)

11. What are 1-D elements? Give examples.


Elements having a minimum of two nodes are called 1D element. Beams are usually approximated with 1D element. These may be straight or curved. There can be additional nodes within the element.


12. What are 2-D elements? Give examples.

A plane wall, plate, diaphragm, slab, shell etc. can be approximated as an assemblage of 2-D

elements. Most commonly used elements are triangular, rectangular and quadrilateral elements.



13. What are 3-D elements? Give examples.

3-D elements are used for modeling solid bodies and the various 3-D elements are tetrahedron, hexahedron, and curved rectangular solid.


14. Define Shape function.

Shape function is also called an approximate function or an interpolation function whose value is equal to unity at the node considered and zeros at all other nodes. Shape function is represented by Ni where i = node no.


15. What are the properties of shape functions?

The properties of shape functions are:

Ø The no of shape functions will be equal to the no of nodes present in the element.

Ø Shape function will have a unit value at the node considered and zero value at other nodes.

Ø The sum of all the shape function is equal to 1.


16. Define aspect ratio.

Element aspect ratio is defined as the ratio of the largest dimension of the element to its smallest dimension.


17. What are possible locations for nodes?

The possible locations for nodes are:

Ø Point of application of concentrated load.

Ø Location where there is a change in intensity of loads

Ø Locations where there are discontinuities in the geometry of the structure

Ø Interfaces between materials of different properties.


18. What are the characteristics of displacement functions?

Displacement functions should have the following characteristics:

Ø The displacement field should be continuous.

Ø The displacement function should be compatible between adjacent elements

Ø The displacement field must represent constant strain states of elements

Ø The displacement function must represent rigid body displacements of an element.


19. What is meant by plane strain condition?

Plane strain is a state of strain in which normal strain and shear strain directed perpendicular to the plane of body is assumed to be zero.




1. What is a plastic hinge?

When a section attains full plastic moment Mp, it acts as hinge which is called a plastic hinge. It is defined as the yielded zone due to bending at which large rotations can occur with a constant value of plastic moment Mp.


2. What is a mechanism?

When a n-degree indeterminate structure develops n plastic hinges, it becomes determinate and the formation of an additional hinge will reduce the structure to a mechanism. Once a structure becomes a mechanism, it will collapse.


3. What is difference between plastic hinge and mechanical hinge?

Plastic hinges modify the behavior of structures in the same way as mechanical hinges. The only difference is that plastic hinges permit rotation with a constant resisting moment equal to the plastic moment Mp. At mechanical hinges, the resisting moment is equal to zero.


4. Define collapse load.

The load that causes the (n + 1) the hinge to form a mechanism is called collapse load where n is the degree of statically indeterminacy. Once the structure becomes a mechanism


5. List out the assumptions made for plastic analysis.

The assumptions for plastic analysis are:

Ø Plane transverse sections remain plane and normal to the longitudinal axis before and after bending.

Ø Effect of shear is neglected.

Ø The material is homogeneous and isotropic both in the elastic and plastic state.

Ø Modulus of elasticity has the same value both in tension and compression.

Ø There is no resultant axial force in the beam.

Ø The cross-section of the beam is symmetrical about an axis through its centroid and parallel to the plane of bending.


6. Define shape factor.

Shape factor (S) is defined as the ratio of plastic moment of the section to the yield moment of the section.


Where Mp = Plastic moment

M = Yield moment

Zp = Plastic section modulus

Z = Elastic section modulus


7. List out the shape factors for the following sections.

(a) Rectangular section, S = 1.5

(b) Triangular section, S = 2.346 (c) Circular section, S = 1.697 (d) Diamond section, S = 2


8. Mention the section having maximum shape factor.

The section having maximum shape factor is a triangular section, S = 2.345.


9. Define load factor.

Load factor is defined as the ratio of collapse load to working load and is given by



10. State upper bound theory.

Upper bound theory states that of all the assumed mechanisms the exact collapse mechanism is that which requires a minimum load.


11. State lower bound theory.

Lower bound theory states that the collapse load is determined by assuming suitable moment distribution diagram. The moment distribution diagram is drawn in such a way that the conditions of equilibrium are satisfied.


12. What are the different types of mechanisms?

The different types of mechanisms are:

Ø Beam mechanism

Ø Column mechanism

Ø Panel or sway mechanism

Ø Cable mechanism

Ø Combined or composite mechanism


13. Mention the types of frames.

Frames are broadly of two types: (a) Symmetric frames

(b) Un-symmetric frames


14. What are symmetric frames and how they analyzed?

Symmetric frames are frames having the same support conditions, lengths and loading conditions on the columns and beams of the frame. Symmetric frames can be analyzed by:

(a) Beam mechanism

(b) Column mechanism


15. What are unsymmetrical frames and how are they analyzed?

Un-symmetric frames have different support conditions, lengths and loading conditions on its columns and beams. These frames can be analyzed by:

(a) Beam mechanism

(b) Column mechanism

(c) Panel or sway mechanism

(d) Combined mechanism


16. Define plastic modulus of a section Zp.

The plastic modulus of a section is the first moment of the area above and below the equal area axis. It is the resisting modulus of a fully plasticized section.

Zp = A/2 (y1 + y2)


17. How is the shape factor of a hollow circular section related to the shape factor of a ordinary circular section?

The shape factor of a hollow circular section = A factor K x shape factor of ordinary circular


SF of hollow circular section = SF of circular section x {(1 – c3)/ (1 – c4)}


18. Give the governing equation for bending.

The governing equation for bending is given by

M/I = /y

Where M = Bending moment

I = Moment of inertia

y = c. g. distance


19. Give the theorems for determining the collapse load.

The two theorems for the determination of collapse load are: (a) Static Method [Lower bound Theorem]

(b) Kinematic Method [Upper bound Theorem]




1. What are cable structures?

Long span structures subjected to tension and uses suspension cables for supports. Examples of cable structures are suspension bridges, cable stayed roof.


Suspension bridge – cable structure

2. What is the true shape of cable structures?

Cable structures especially the cable of a suspension bridge is in the form of a catenary. Catenary is the shape assumed by a string / cable freely suspended between two points.


3. What is the nature of force in the cables?

Cables of cable structures have only tension and no compression or bending.


4. What is a catenary?

Catenary is the shape taken up by a cable or rope freely suspended between two supports and under its own self weight.


5. Mention the different types of cable structures.

Cable structures are mainly of two types: (a) Cable over a guide pulley

(b) Cable over a saddle


6. Briefly explain cable over a guide pulley.

Cable over a guide pulley has the following properties:

Ø Tension in the suspension cable = Tension in the anchor cable

Ø The supporting tower will be subjected to vertical pressure and bending due to net horizontal cable tension.


7. Briefly explain cable over saddle.

Cable over saddle has the following properties:

Ø Horizontal component of tension in the suspension cable = Horizontal component of tension in the anchor cable

Ø The supporting tower will be subjected to only vertical pressure due to cable tension.


8. What are the main functions of stiffening girders in suspension bridges?

Stiffening girders have the following functions.

Ø They help in keeping the cables in shape

Ø They resist part of shear force and bending moment due to live loads.


9. What is the degree of indeterminacy of a suspension bridge with two hinged stiffening girder?

The two hinged stiffening girder has one degree of indeterminacy.


10. Differentiate between plane truss and space truss.

Plane truss:

Ø All members lie in one plane

Ø All joints are assumed to be hinged.

Space truss:

Ø This is a three dimensional truss

Ø All joints are assumed to be ball and socketed.


11. Define tension coefficient of a truss member.

The tension coefficient for a member of a truss is defined as the pull or tension in the member divided by its length, i. e. the force in the member per unit length.


12. Give some examples of beams curved in plan.

Curved beams are found in the following structures.

Ø Beams in a bridge negotiating a curve

Ø Ring beams supporting a water tank

Ø Beams supporting corner lintels

Ø Beams in ramps


13. What are the forces developed in beams curved in plan?

Beams curved in plan will have the following forces developed in them:

Ø Shear forces

Ø Torsional moments


14. What are the significant features of circular beams on equally spaced supports?

Ø Slope on either side of any support will be zero.

Ø Torsional moment on every support will be zero


15. Give the expression for calculating equivalent UDL on a girder.

Equivalent UDL on a girder is given by:



16. Give the range of central dip of a cable.

The central dip of a cable ranges from 1/10 to 1/12 of the span.


17. Give the expression for determining the tension T in the cable.

The tension developed in the cable is given by


Where, H = horizontal component and V = vertical component.


18. Give the types of significant cable structures

Linear structures:

Ø Suspension bridges

Ø Cable-stayed beams or trusses

Ø Cable trusses

Ø Straight tensioned cables

Three-dimensional structures:

Ø 3D cable trusses

Ø Tensegrity structures

Ø Tensairity structures


19. What are cables made of?

Cables can be of mild steel, high strength steel, stainless steel, or polyester fibres. Structural cables are made of a series of small strands twisted or bound together to form a much larger cable. Steel cables are either spiral strand, where circular rods are twisted together or locked coil strand, where individual interlocking steel strands form the cable (often with a spiral strand core).

Spiral strand is slightly weaker than locked coil strand. Steel spiral strand cables have a Young's modulus, E of 150 ± 10 kN/mm² and come in sizes from 3 to 90 mm diameter. Spiral strand suffers from construction stretch, where the strands compact when the cable is loaded.

CE2352 Design of Steel Structures Two Marks with Answers for May June 2013 Exam

CE2352 Design of Steel Structures

2013 Edition


UNIT – i - Connections – riveted, welded & bolted

1. Mention the advantages and disadvantages of steel structures?


ü Ability to resist high loads

ü Due to its high density, steel is completely non-porous

ü Durability

ü Easy to disassembling or replacing some steel members of a structure


ü Corrosion

ü At high temperature steel loses most of its strength, leading to deformation or failure

2. What is meant by Girder?

Girder means a major beam frequently at wide spacing that supports small beams.

3. What is meant by joists?

It is a closely spaced beam supporting the floors and roofs of buildings

4. What is meant by Purlins?

It is a roof beam usually supported by trusses

5. What is meant by Rafters?

It is a roof beam usually supported by purlins

6. What is meant by Lintel?

It is a beam over window or door openings that support the wall above.

7. What is Girts?

It is horizontal wall beams used to support wall covering on the side of an industrial building

8. What is meant by Spandrel beam?

It is beam around the outside perimeter of a floor that support the exterior walls and the outside edge of the floor

9. Name the different types of connections?

ü Riveted connections

ü Welded connections

ü Bolted connections

ü Pinned connections

10. Name the types of riveted connections?

ü Lap Joint - single riveted and double riveted

ü Butt joint – single cover and double cover

11. What is meant by rivet value?

The least of the strengths in shearing and bearing is the rivet value

12. What is meant by gauge distance?

The perpendicular distance between two gauge lines, is called gauge distance

13. Name the different modes of failure of a riveted joint?

ü Tearing failure of the plate

ü Shear failure of the plate

ü Shear failure of the rivet

ü Bearing failure of the rivet

ü Splitting failure of plate

14. As per the American practice where the neutral axis lie in the rivet group?

It is assumed that the line of rotation lies at a distance of 1/7 th of the effective bracket depth from the bottom of the bracket

15. What are the factors that govern will govern the structural design?

ü Foundation movements

ü Elastic axial shortening

ü Soil and fluid pressures

ü Vibration

ü Fatigue

ü Impact (dynamic effects)

ü Erection loads

16. What are the load combinations for the design purposes?

ü Dead load + Imposed Load (Live load)

ü Dead Load + Imposed Load + Wind Load or earthquake load

ü Dead Load + Wind Load or Earthquake load

17. What are the steps involved in structural design?

ü Forces or loads

ü Structural arrangement and material selection

ü Analyzing internal stresses

ü Proportioning of members

18. Which type of steel is most commonly used in general construction? Why?

Mild Steel is most commonly used in general construction because of its durability

and malleability

19. What are Black bots? Where are they used?

Black bolts made from M.S shank left unfinished – remain loose in holes resulting in large deflections. It is used during erection and for temporary structures

20. How the rolled steel beams are classified?

ü Indian Standard junior beams (ISLB)

ü Indian Standard light beams (ISLB)

ü Indian Standard medium weight beams (ISMB)

ü Indian Standard wide flange beams (ISWB)

21. Define permissible stresses and Working stresses.

Permissible stresses = clip_image002

Working stresses: The stresses used in practical design are working stresses and they should never exceed the permissible stresses specified by codes.

22. Explain ISLB 200?

ISLB 200 means Indian Standard light gauge beams of depth 200mm

23. Name the types of beam connections?

ü Framed connections

ü Seated connections – Stiffened connections and Unstiffened connections

24. What is meant by framed connections?

A framed connection is the one when a beam is connected to girder or a stanchion by means of two angles placed on the two sides of the web of the beam

25. When the seated beam connections are preferred and name the types?

When a beam is connected to the flange (or the web) of a steel stanchion, the width of the flange (or the depth of the web) may be insufficient to accommodate the connecting angles, in such cases framed connection is not suitable and seated connection is preferred.

26. What is unstiffened seat connection?

The seated connection is a horizontal angle with its horizontal leg at its top is used to receive the beam on it, in such a case it is called unstiffened seat connection

27. What is stiffened seat connection?

In addition to the seat angle, a web cleat is provided when the beam is connected to a beam and a flange cleat is used when the beam is connected to a stanchion. The angle cleats are essential because they keep the beam stable in a vertical position and prevent it from lateral buckling

28. What is meant by throat thickness?

It is the perpendicular distance from the root to the hypotenuse of the largest

isosceles right-angled triangle that can be inscribed within the weld cross-section.

Throat thickness = 0.7 x size of the weld

29. What is plug weld and slot weld?

Slot weld is one of the type of weld used to join the two touching contiguous

components by a fillet weld round the periphery of a slot in one component so as to join it the surface of other component.

Plug weld is made by filling in a hole in one part with filler metal so as to join it to the

contiguous part exposed through a hole.

30. Mention the advantages and disadvantages of welded connections?


ü Economy

ü Rigidity

ü Aesthetic effect

ü Versatility


ü Requires skilled labour

ü Joints are over rigid

ü Difficult to inspect

31. State the common defects in welding

ü Incomplete fusion

ü Incomplete penetration

ü Porosity

ü Slag inclusions

ü Cracks

ü Under cutting

32. Name the types of bolted connections?

ü Ordinary unfinished 0r black bolts

ü Turned and fitted bolts

ü High strength bolts

33. Write the advantages of high strength bolts?

ü As there is no slip between the plates, the joint is rigid

ü Alternating loads cause little variation of the stresses in the bolts; hence fatigue strength is also high.

ü No shearing or bearing stresses occur in bolts.

ü High strength of the joint due to high frictional resistance is obtained.

34. Write down the interaction equation?


35. How will you calculate the number of rivets?


where P is the pull or push carried by the member.


1. Tie member – Explain.

Tie member or a tension member is a structural element carrying an axial tensile force. For the tensile force to be axial it is necessary that the load be applied through centroid of the section of the member. But under axial tension the member gets straightened and eccentricity of the force decreases. The member is almost straight at the yield point and the distribution of the stress over the section becomes uniform.

2. How the tension members are classified?

It is classified according to its shape and size and it depends upon the type of structures.

ü Wires and cables – Used in hoists, derricks, suspenders in suspension


ü Rods and bars – Used in radio tower, small spanned roof trusses with

different cross-sections such as round, rectangular or square

3. What is meant by single section member?

Structural sections such as I-section, T-section, angle, and channel are used as tension members. As the structural shapes provide more rigidity than cables or rods, their buckling tendency under compression load is reduced and so can be used where reversal of stress takes place.

4. Under what circumstances you would go for Built-up members?

When single structural sections fail to provide required strength and stiffness to carry tension as well as compression in case of reversal of stresses, built-up members are used.

5. How the tension members are selected?

It depends upon the various factors such as type of fabrication, type of structure, type of loading, i.e. whether the member undergoes reversal of stresses, and the maximum tension to be carried by the member.


6. Sketch the different forms a single section member

7. Sketch the different forms Built-up members.

Built up members

8. How is net effective area of single angle used as tension member calculated?

Net effective area = A1 + A2K

A1- Net area of connected leg

A2- area of outstanding leg

K = clip_image011

9. What is net sectional area of a tension member? How it is calculated in chain riveting?

The gross sectional area of the tension member minus the sectional area of the maximum number of rivet/bolt holes is known as net sectional area.

In case of chain riveting,

anet= (b – nd) t

10. What is Lug angle?

A larger length of the tension member and the gusset plate may be required sometimes to accommodate the required number of connection rivets. But this may not be feasible and economical. To overcome this difficulty lug angles are used in conjunction with main tension members at the ends. It provides extra gauge lines for accommodating the rivets and thus enables to reduce the length of the connection. They are generally used when the members are of single angle, double angle or channel sections.

11. What are the main objectives of the lug angles?

ü They produce eccentric connections, due to rivets placed along lug angle. The centroid of the rivet system of the connection shifts, causing eccentric connection and bending moments.

ü Stress distribution in the rivets connecting lug angles is not uniform. It is preferred to put a lug angle at the beginning of the connection where they are more effective and not at the middle or at the end of the connection.

ü Rivets on the lug angles are not as efficient as those on the main member. The

out-standing leg of the lug angle usually gets deformed and so the load shared by the

rivets on the lug angles is proportionately less.

12. What is meant by Tension splice?

Splicing of tension members is necessary when the required length of the member is more than the length available or when the member has different cross-sections for different parts of its length. If actual member is to be of greater length, two or more lengths shall have to be spliced at the joints.

  1. What is the net effective area of a pair of angles placed back to back connected by one leg of each angle subjected to tension?

Anet = A1 + A2 K

A1 - effective cross – section area of connected legs

A2 – Gross area of outstanding legs

K = clip_image013

  1. What is the permissible stress in axial tension?

As per IS: 800 – 1984, the permissible stress in axial tension

sat = 0.6 fy N/mm2

fy = minimum yield stress in steel in N /mm2.

  1. How will you join the member of different thickness in a tension member?

When tension member of different thickness are to be jointed, filler plates may be used to bring the member in level.

  1. What happens when a single angle with one leg is connected to a gusset plate, which is subjected to an eccentric load?

The rivets connecting the angle to the gusset plate does not lie on the line of action of load. This gives rise to an eccentric connection due to which the stress distribution becomes non-uniform. The net cross-sectional area of such a section is reduced to account for this non-uniform stress distribution resulting from eccentricity.

  1. What is the allowable stress in axial tension for channel section?

The allowable stress in axial tension for channel section is depends upon the diameter of the section


sat = 0.6 fy N/mm2

Upto 20mm


20mm to 40 mm


Over 40 mm


  1. What are tacking rivets? Why are they essential in compression members?

Rivets used to connect long length of members to reduce the effective length of individual part

  1. Write down the Steinman’s formula

Anert = clip_image015

Where n = no. of rivets in the section considered

m= no. of zig zags or inclined lines.

  1. What will be the maximum pitch when the angles are placed back to back?

The maximum pitch when the angles are placed back to back is 1mm.

UNIT – III - compression members

  1. What do you mean by compression members?

Compression members are the most common structural elements and it is termed as columns, struts, posts or stanchions. They are designed to resist axial compression.

2. Name the modes of failures in a column.

ü Failure of the cross-section due to crushing or yielding

ü Failure by buckling, due to elastic instability

ü Mixed mode of failure due to crushing and buckling

3. Define slenderness ratio

It is defined as the ratio of effective length l of the column to the least radius of gyration r of the column section.

4. Classify the columns according to the slenderness ratios.

ü Short columns - l/r <60

ü Medium columns - 60< l/r <100

ü Long columns - l/r >100

5. Distinguish column and strut

Columns are the vertical members which carry the loads to the beams, slabs etc, generally they are used in ordinary buildings.

Struts are commonly used for compression members in a roof truss; it may either be in vertical position or in an inclined position.

6. What is meant by stanchions?

These are the steel columns made of steel sections, commonly used in buildings.

7. What is Post?

It is loosely used for a column, but in truss bridge girders, end compression members are called end posts.

8. What is a boom?

It is the principal compression member in a crane.

9. State the assumptions that made in Euler’s theory.

ü The axis of the column is perfectly straight when unloaded.

ü The line of thrust coincides exactly with the unstrained axis of the strut.

ü The flexural rigidity EI is uniform

ü The material is isotropic

10. Why the lateral systems are provided in compound columns?

If the plates are not connected throughout their length of the Built up sections, lateral systems may be provided, which act as a composite section. In such cases the load carrying elements of the built-up compression member in the relative position, without sharing any axial load. However when the column deflects, the lateral system carries the transverse shear force.

11. Name the lateral systems that are used in compound columns and which is the mostly used one?

Lacing or latticing, Battening or batten plates, perforated cover plates.

Lacing or latticing is the most common used lateral system and the sections are flats, angles and channels.

12. What will be the thickness for the single and double lacing bars?

The thickness of flat lacing bars shall not be less than one-fortieth of the length between the inner end rivets or welds for single lacing, and one-sixtieth of the length for double lacing.

13. What is the purpose of providing battens in compound steel columns?

Batten plates consist of flats or plates, connecting the components of the built-up columns in two parallel planes. These are used only for axial loading. Battening of the composite column should not be done if it is subjected to eccentric loading or a applied moment in the plane of battens.

14. What is the thickness of a batten plate?

The thickness of batten plate shall not be less than one fiftieth of the distance between the inner most connecting lines of rivets or welds. This requirement eliminates lateral buckling of the batten.

15. Where the perforated cover plates are used and mention its advantages?

They are mostly used in the box sections, which consist of four angle sections so that

the interior of column remains accessible for painting and inspection.


ü They add to the sectional area of column and the portions beyond the perforation share axial load to the extent of their effective area.

ü There is economy and fabrication and maintenance

ü Perforations conveniently allow the riveting and painting work on the inside portion.

16. Name the types of column base?

ü Slab Base, which is a pinned base.

ü Gusseted base, which is a rigid base.

17. State the purpose of column base?

The base of the column is designed in such a way to distribute the concentrated column load over a definite area and to ensure connection of the lower column end to the foundation. It should be in adequate strength, stiffness and area to spread the load upon the concrete or other foundations without exceeding the allowable stress.

18. Give the difference between slab base and gusseted base for steel columns.

Slab base is a thick steel base plate placed over the concrete base and connected to it through anchor bolts. The steel base plate may either be shop-welded to the stanchion, or else can be connected at the site to the column through cleat angles. The column is faced for bearing over the whole area.

In a gusseted base, part of the load is transmitted from the stanchion through the gusseted base plate. The gussets and stiffeners support the base slab against bending and hence a thinner base plate can be used. The gussets serve for more or less uniform transmission of the force field from the column to the base plate. The gussets itself resists the bending as double cantilever beam supported on flanges of the column.

19. What is slab base and for what purpose is it provided?

The base plate connected to the bottom of the column to transfer over wider area is known as slab base. Column end is machined to transfer the load by direct bearing. No gusset materials are required.

20. When the slenderness ratio of compression member increases, the permissible stress decreases. Why?

The section must be so proportioned that it has largest possible moment of inertia for the same cross-sectional area. Also the section has approximately the same radius of gyration about both the principal axes.


  1. What is a beam?

A beam is a structural member, which carries a load normal to the axis. The load produces bending moment and shear force in the beam.

  1. What is meant by castellated beam?

A rolled beam with increased depth is to be castellated. To obtain such sections, a zigzag line is cut along the beam by an automatic flame-cutting machine. The two halves thus produced are rearranged so that the teeth match up and the teeth are then welded together.

  1. How the beams are failed?

ü Bending failure

ü Shear failure

ü Deflection failure

The designs are based on these three failures which are to be determined.

  1. What do you mean by bending failure?

Bending failure may be due to crushing of compression flange or fracture of the tension flange of the beam. Instead of failure due to crushing, the compression flange may fail by a column like action with side ways or lateral buckling. Collapse would follow the lateral buckling.

  1. What is the maximum deflection that to be allowed in steel beams?

The deflection of a member, shall not be such as to impair the strength or efficiency of the structure and lead to finishing. The deflection is generally should not exceed 1/325 of the span.

  1. What is web crippling?

Web crippling is the localized failure of a beam web due to introduction of an excessive load over a small length of the beam. It occurs at point of application of concentrated load and at point of support of a beam. A load over a short length of beam can cause failure due to crushing and due to compressive stress in the web of the beam below the load or above the reaction. This phenomenon is also known as web crippling or web crushing.

  1. What are laterally supported beams?

The beams which are provided with the lateral supports either by embedding the compression flange in the concrete slab or by providing effective intermediate (support) restraints at a number of points to restrain the lateral buckling is called laterally supported beams.

  1. Mention the advantages of using rolled steel wide flange section as beams

ü More section modulus

ü Lesser area

ü Economical

  1. Why does buckling of web occur in beams?

ü Diagonal compression due to shear

ü Longitudinal compression due to bending

ü Vertical compression due to concentrated loads

  1. What are the permissible stresses used in the beams?

The permissible stresses, which are used in the beams are bending and shear stress.

Bending Stress

ü For laterally supported beams,


ü For laterally unsupported beams,

clip_image019 , Where n is assumed to be 1.4

Shear Stress

clip_image021, clip_image023 = maximum permissible shear stress

  1. Under what situations the plated beams are used?

ü When a bending moment is large which cannot be resisted by the largest available rolled beam section

ü The depth of the beam is restricted due to headroom requirements.

  1. Why intermediate stiffeners are required for plate girders?

The web of the plate girder relatively being tall and thin it is subjected to buckling. Hence it is stiffened both vertically and horizontally using intermediate stiffeners.

  1. What do you mean by curtailment of flanges?

The section of a plate girder is to be designed first at mid span. The bending moment will goes on decreasing towards the supports. Hence the flange plates, provided at the maximum section can be curtailed.

  1. What is the purpose of providing the bearing stiffener?

ü It prevents the web from crushing and buckling sideways, under the action of concentrated loads

ü It relieves the rivets connecting the flange angles and web, from vertical shear.

  1. Name the components of a plate girder.

ü Web plate

ü Flange plate

ü Flange angles

ü Web splice plates

ü Flange splice plates

ü Vertical or transverse stiffeners

ü Bearing stiffeners

ü Longitudinal or horizontal stiffeners

ü End bearings or end connections

  1. Mention the basic design assumptions of a plate girder?

ü The web plate resists the shear force.

ü The shear stress is uniformly distributed over whole cross sectional area of web.

ü The flanges resist the bending moment

  1. Where the plate girders are used?

The plate girders are used in the buildings where the span is more and heavy loads are expected and in the bridges. Most commonly they are used in the bridges.

  1. What are the methods that are adopted to determine the flange design?

ü Flange area method

ü Moment of inertia method

The former method is an approximate method, which is used for determining the trial section. In this method, it is assumed that the stress distribution in the tension and compression

flanges is uniform, whereas in the latter case it is the exact method and is recommended by the IS code. Generally, the section designed by the flange area method is checked by this method.

  1. What is the economical depth of a plate girder?

The economical depth of a plate girder is

clip_image025, where clip_image027= permissible bending stress in compression in N/mm2.

clip_image029 = thickness of the web plate.

  1. The pitch of the rivets connecting cover plates with flanges of rolled steel beam is designed for what force?

These rivets are designed for horizontal shear between the flange plate and flange angles. Since the vertical load is transferred by the flange plates to the flange angles by direct bearing, there will be no vertical shear due to the vertical load. Here the rivets will be in single shear.

  1. Name the types of roofing systems.

ü Flat roofing consists of either RCC construction or RSJ slab construction

ü Sloping roofing

  1. Where the steel roof trusses are used?

Industrial buildings, workshop buildings, storage godowns, warehouse and even for residential buildings, school buildings, offices where the construction work is to be completed in a short duration of time.

  1. Mention the advantages of a roof truss.

ü Its mid-span depth is the greatest specially where bending moment in the span is the maximum

ü Great economy.

ü Sloping faces of trusses facilitate in easy drainage of rainwater.

  1. What is the factor that is considered in the roof truss and why?

The factor, which is considered in the roof truss, is pitch, it is defined as the ratio of the span length to the depth of the truss, is governed by the roofing material and other requirements such as ventilation and light.

  1. How the trusses are classified according to the pitch?

ü Small pitch - span depth ratio is more than 12 m

ü Medium pitch - span depth ratio is between 5m to 12 m

ü Large pitch - span depth ratio is 5 or less.

  1. Sketch the various types of roof truss.


  1. Name the components of a roof truss.

ü Principal rafter or top chord

ü Bottom chord or main tie

ü Ties

ü Struts

ü Sag tie

ü Purlins

ü Rafters

ü Ridge line

ü Eaves

ü Panel points

ü Roof coverings

ü Shoe angle

ü Base plate, anchor plate and anchor bolts

  1. What is gantry girder and what are the forces that are acting on it?

A gantry girder, having no lateral support in its length, has to withstand vertical loads from the weight of the crane, hook load and impact and horizontal loads from crane surge.

  1. What is meant by purlins?

Purlins are structural members which are supported on the principal rafter, and which run transverse to the trusses. The span of the purlins is equal to the center-to-center spacing of the trusses. The purlins support the roof covering either directly or through common rafters. They are usually made of either an angle section or a channel section and are therefore subjected to unsymmetrical bending.

  1. Why the bracings are provided?

Bracing is required to resist horizontal loading in pin-jointed buildings, including roof trusses. Bracing of roof trusses and supporting columns provide still rigid structure. When wind blows normal to the inclined surface of the trusses, it is efficiently resisted by all the members of the truss and the wind forces are transferred to the supports at the ends of the truss.

  1. Name the most common roof covering materials.

ü Slates

ü Tiles

ü Lead sheets

ü Zinc sheets

ü Glass

ü Corrugated aluminium sheets

ü Galvanized corrugated iron sheets (G.I. sheets)

ü Asbestos cement sheets (A.C. sheets)

  1. Write the equation to calculate the design wind pressure.

Design pressure is clip_image033

clip_image035 = Basic wind speed in m/s at 10 m height

clip_image037= Probability factor (or risk coefficient)

clip_image039= Terrain, height and structure size factor

clip_image041=Topography factor

  1. Mention some of the requirements of a good joint.

ü The line of thrust should pass through the C.G of the rivet group and the rivets should be symmetrically arranged about this line.

ü For a tension member, the rivets should be so arranged that the area of the member joined is not reduced more than necessary.

ü The number and the diameter of rivets should be sufficient to develop the maximum stresses induced in all the members at the connection.

ü Members should be straight and bolts used to draw them together before the rivets are driven.

14. What are the conditions that to be satisfied for the end supports?

ü The size of base plate should be sufficient so that the bearing pressure does not exceed the permissible value.

ü Anchor bolts should be provided at one end to accommodate the thermal expansion of the truss.

ü The lines of forces in rafter, bottom tie and vertical end reaction meet at a point.

  1. Where the gantry girders are used?

Gantry girders or crane girders carry hand operated or electric over head cranes in industrial buildings such as factories, workshops, steel works etc., to lift heavy materials, equipment etc., to carry them from one location to the other, within the building.

  1. Sketch the various forms of gantry girders.


Forms of gantry girders

  1. What is drag force?

This is caused due to the starting and stopping of the crane bridge moving over the crane rails as the crane m0oves longitudinally, i.e. in the direction of gantry girders.

  1. What is the permissible deflection where the electrically overhead cranes operated over 500kN?

The maximum vertical deflection for crane girder, under dead and imposed loads shall not exceed L/1000, where L is the span of the crane runway girder.

  1. Define shoe angle.

It is a supporting angle provided at the junction of the top and bottom chords of a truss. The reaction of the truss is transferred to the supports through the shoe angle. It is supported on the base plate.

  1. What is panel point?

These are the prominent points along the principal rafter, at which various members (i.e. ties and struts) meet. The distance of the principal rafter between any two panel point is termed as panel.