Structural Analysis – II (NCE-504)
Section-Wise Important Questions & Study Notes
SECTION–A
(Attempt all questions | 2 × 10 = 20)
This section checks definitions, concepts, and theory basics.
Write 2–3 lines only, no derivations.
Carry Over Moment
The moment induced at the far end of a member when a moment is applied at the near end, with the far end fixed.
Castigliano’s Second Theorem
The partial derivative of strain energy with respect to an applied force gives the displacement in the direction of that force.
Why Two-Hinged Arch Is Indeterminate
Because it has one redundant reaction (horizontal thrust), making it statically indeterminate to degree one.
Horizontal Thrust Using Castigliano’s Theorem
Horizontal thrust is obtained by differentiating strain energy with respect to horizontal reaction and equating displacement to zero.
Range of Central Dip
The central dip of a suspension cable lies between 1/10 to 1/12 of the span for economical design.
Effect of Temperature Change in Cable
Increase in temperature increases sag and reduces tension; decrease in temperature reduces sag and increases tension.
Stiffness Coefficient
Force required to produce unit displacement at a degree of freedom while all other displacements are restrained.
Objectives of Structural Analysis
To determine reactions, internal forces, moments, deflections, and assess safety and serviceability.
Plastic Modulus vs Section Modulus
Section modulus is elastic; plastic modulus is based on fully plastic stress distribution.
Plastic Hinge
A section where plastic moment capacity is reached and rotation occurs without increase in moment.
SECTION–B
(Attempt any THREE | 10 × 3 = 30)
Numericals + diagrams are compulsory.
1. Continuous Beam – Slope Deflection Method
Find support moments Write slope-deflection equations
Apply boundary conditions Draw BMD
2. Influence Line Diagram (Müller-Breslau Principle)
State the principle Draw deflected shape
Construct influence line for moment at mid-span
3. Cable Analysis with Pier
Given: Span, dip, UDL
Find horizontal tension Maximum cable tension
Forces on pier Maximum bending moment in pier
4. Continuous Beam with Support Settlement (Flexibility Method)
Choose redundants Write compatibility equations
Form flexibility matrix Calculate reactions and moments
5. Limit State Design – Required Section Modulus
Use load factor & shape factor Compute design moment
Find plastic section modulus
SECTION–C
(Attempt any ONE | 10 × 1 = 10)
3(a) Continuous Beam – Moment Distribution Method
Distribution factors Carry over factors
Moment balancing Final support moments and BMD
OR
3(b) Method of Consistent Deformation
Primary structure Compatibility equations
Redundant forces BMD
