CE1352 Structural Analysis B.E Question Bank : kings.ac.in

Name of the College : Kings College of Engineering
University : Anna University Chennai
Department : Civil Engineering
Subject Code/Name : CE 1352/ Structural Analysis- II
Year : III
Semester : VI
Degree : B.E
Website : kings.ac.in
Document Type : Question Bank

Download :  https://www.pdfquestion.in/uploads/ki…NALYSIS%20.pdf

Structural Analysis Question Paper

Unit-I

Flexibility Matrix Method For Indeterminate Structures :
Part-A :
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

Related : Kings College of Engineering CE1356 Railway Engineering B.E Question Bank : www.pdfquestion.in/1548.html

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. Define degree of indeterminacy (i) :
The excess number of reactions that make a structure indeterminate is called degree of indeterminacy, and is denoted by (i). Indeterminacy is also called degree of redundancy. Indeterminacy consists of internal and external indeterminacies.
i = II + EI where II = internal indeterminacy and EI = external indeterminacy.

4. Define internal and external indeterminacies :
Internal indeterminacy (II) is the excess no of internal forces present in a member that make a structure indeterminate.
External indeterminacy (EI) is excess no of external reactions in the member that make the structure indeterminate.
i = II + EI;
EI = r – e; where r = no of support reactions and e = equilibrium conditions
II = i – EI
e = 3 (plane frames) and e = 6 (space frames)

5. 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

6.What are the different methods of analysis of indeterminate structures :
The various methods adopted for the analysis of indeterminate structures include :
(a) Flexibility matrix method.
(b) Stiffness matrix method
(c) Finite Element method

7. Briefly mention the two types of matrix methods of analysis of indeterminate structures :
The two matrix methods of analysis of indeterminate structures are :
(a) 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.
(b) 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.

8. 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.

9. Define kinematic indeterminacy (Dk) or Degree of Freedom (DOF) :
Degrees 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.

10. 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.

11. 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

12. 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][u] {R}
where Q = member force matrix/vector
b = force transformation matrix
R = external force/load matrix/ vector

13.What are the requirements to be satisfied while analyzing a structure? :
The three conditions to be satisfied are :
(a) Equilibrium condition
(b) Compatibility condition
(c) Force displacement condition

14. 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 all other joints are not load.

15. Write the element flexibility matrix (f) for a truss member :
The element flexibility matrix (f) for a truss member is given by 8

Unit – II

Stiffness Matrix Method
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 all 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 quilibrium 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