All Free Civil Engineering MCQs with Answers

• A. Pab squared divided by L squared
• B. Pa squared b divided by L squared
• C. Pab divided by L
• D. P times L divided by ab

Explanation: For a point load on a fixed-ended beam, the magnitude of the left fixed-end moment is Pab squared divided by L squared.

• A. The span of the arch
• B. The rise of the crown hinge above the springing chord
• C. The vertical reaction at either support
• D. The total applied load on the arch

Explanation: At the crown hinge, the arch bending moment is zero. Equating the arch moment to the simply supported beam moment minus the horizontal…

• A. The elastic modulus of each member
• B. The density of the applied load
• C. The lateral translation of a joint or storey
• D. The plastic moment of each support

Explanation: A sway frame allows lateral joint translation, so the slope-deflection equations include displacement terms in addition to end rotations.

• A. To remove all applied loads before solving the structure
• B. To calculate member stresses without assembling a stiffness matrix
• C. To convert every flexible support into a fixed support
• D. To reduce the system by eliminating selected internal degrees of freedom

Explanation: Static condensation eliminates selected degrees of freedom algebraically and produces a smaller system for the remaining primary…

• A. Curvature equals M divided by EI
• B. Curvature equals EI divided by M
• C. Curvature equals V divided by EI
• D. Curvature equals M divided by EA

Explanation: Euler-Bernoulli beam theory relates curvature to bending moment through M divided by EI, where E is Young's modulus and I is the second…

• A. Thermal expansion only
• B. Shear deformation
• C. Axial shortening only
• D. Torsional yielding at every section

Explanation: In a deep or short-span beam, shear strain contributes appreciably to total deflection and should not be ignored.

• A. Unequal, opposite, and collinear
• B. Equal, parallel, and perpendicular
• C. Equal, opposite, and collinear
• D. Equal, opposite, and concurrent elsewhere

Explanation: A two-force member carries only axial tension or compression when its two end forces are equal, opposite, and act along the same straight…

• A. Rectangular and indefinite
• B. Antisymmetric and singular
• C. Diagonal and unsymmetric
• D. Symmetric and positive definite

Explanation: For a stable structure with conservative linear elastic behavior, the assembled stiffness matrix is symmetric and positive definite after…

• A. 2EI/L
• B. 3EI/L
• C. 4EI/L
• D. 6EI/L

Explanation: When the far end is fixed, rotation at the near end produces an end moment of 4EIθ/L, so the near-end rotational stiffness is 4EI/L.

• A. L/√2
• B. L/2
• C. L
• D. 2L

Explanation: A fixed-fixed column has an effective length factor of 0.5, giving an effective length of L/2.

• A. The joint load is transferred directly to the foundation
• B. The balanced moment is assigned equally to every support
• C. The unbalanced moment is distributed in proportion to member stiffness
• D. The member axial forces are distributed in proportion to span

Explanation: At each joint, the unbalanced moment is distributed among the connected members according to their relative stiffnesses.

• A. Members that carry axial force only
• B. Independent support reactions that must be calculated
• C. Unknown internal forces after equilibrium is applied
• D. Independent displacement components that must be determined

Explanation: Kinematic indeterminacy counts the independent joint translations and rotations remaining after support restraints are considered.

• A. A straight line decreasing from one to zero
• B. A straight line increasing from zero to one
• C. A constant line equal to one
• D. A parabolic curve with zero end values

Explanation: If the unit load is at distance x from the left support on a span L, the left reaction is (L minus x)/L.

• A. The product of load and final displacement only
• B. The area under its load-displacement curve
• C. The maximum bending moment divided by span
• D. The support reaction multiplied by member length

Explanation: For gradually applied load in a linear elastic system, strain energy equals the work done by the load, represented by the area under the…

• A. A support reaction satisfying equilibrium equations
• B. A small elastic deformation under a service load
• C. A deformation without developing sufficient restoring resistance
• D. A temperature strain in an unrestrained member

Explanation: Internal instability occurs when the arrangement of members permits a mechanism or uncontrolled deformation without adequate resisting…

• A. First cracking moment
• B. Yield moment of the outer fibre
• C. Elastic buckling moment
• D. Fully plastic moment

Explanation: A plastic hinge forms when the entire cross section has reached its yield stress distribution, corresponding to the fully plastic moment.

• A. It is symmetric about its main diagonal
• B. It contains only positive off-diagonal terms
• C. It remains unchanged after removing a support
• D. It has identical values in every row

Explanation: Reciprocity makes the stiffness coefficient Kij equal to Kji, so the global stiffness matrix is symmetric.

• A. Force at coordinate i due to unit displacement at j
• B. Displacement at coordinate i due to unit force at j
• C. Rotation at coordinate j due to unit moment at i
• D. Moment at coordinate i due to unit rotation at j

Explanation: The coefficient fij is the displacement at coordinate i caused by a unit force applied at coordinate j.

• A. π²EI divided by L²
• B. π²EI divided by 2L²
• C. π²EI divided by 4L²
• D. 4π²EI divided by L²

Explanation: A fixed-free column has an effective length of 2L. Substituting this into Euler's formula gives Pcr = π²EI divided by 4L².

• A. Uniform transverse pressure
• B. Bending moment only
• C. Shear force and torsion
• D. Axial force only

Explanation: Ideal truss members are connected by frictionless pins and loads act at the joints, so each member behaves as a two-force member.