All Free Civil Engineering MCQs with Answers

• A. vertical jump at the section
• B. constant value over the span
• C. continuous parabolic shape
• D. zero value throughout the span

Explanation: The shear force changes abruptly as the moving load crosses the section, so its influence line has a vertical jump there.

• A. zero
• B. one
• C. two
• D. three

Explanation: A two hinged arch has one redundant horizontal reaction because the ordinary equilibrium equations do not determine all reactions.

• A. area under the shear force diagram
• B. area under the bending moment diagram
• C. area under the M divided by EI diagram
• D. first moment of the load diagram

Explanation: The change in slope equals the area under the curvature diagram, which is M divided by EI.

• A. equal to the maximum span moment
• B. equal to the horizontal thrust
• C. zero only when the loading is symmetrical
• D. zero because the hinge cannot resist moment

Explanation: An ideal internal hinge cannot transmit bending moment, so the moment at the crown hinge is zero for any loading arrangement.

• A. first moment of the M divided by EI area
• B. area of the M divided by EI diagram
• C. average support reaction over the span
• D. maximum curvature multiplied by the span

Explanation: The second moment area theorem states that tangential deviation equals the first moment of the curvature diagram about the point of…

• A. pure bending with no axial force
• B. axial force caused by restrained expansion
• C. zero stress under every restraint condition
• D. torsion caused by thermal rotation

Explanation: A uniform temperature rise causes axial expansion rather than curvature.

• A. [d]{K} = {P}
• B. [P]{d} = {K}
• C. [K]{d} = {P}
• D. [K]{P} = {d}

Explanation: The global stiffness equation is [K]{d} = {P}, where [K] is the stiffness matrix, {d} is the displacement vector, and {P} is the applied…

• A. Unstable under its applied loading
• B. Plastic with unrestricted yielding
• C. Geometrically nonlinear with large rotations
• D. Linear elastic with small deformations

Explanation: Superposition is valid when load response is linear, which generally requires elastic material behavior and small deformations.

• A. Bending moment changes sign
• B. Shear force becomes permanently zero
• C. Deflection reaches its maximum value
• D. Slope remains constant over the span

Explanation: At a point of contraflexure, the bending moment changes from sagging to hogging or vice versa.

• A. One
• B. Three
• C. Two
• D. Six

Explanation: A fixed-ended plane beam has six reaction components, while only three independent equilibrium equations are available.

• A. Every support is converted into a fixed support
• B. All external loads are removed
• C. The redundant forces are released
• D. The member stiffnesses are made equal

Explanation: The selected redundants are removed or released so that the remaining structure becomes stable and statically determinate.

• A. Quarter-height of columns and beam midpoints
• B. Column bases and beam ends
• C. Top of columns and beam supports
• D. Mid-height of columns and midspan of beams

Explanation: The portal method commonly assumes points of contraflexure at the mid-height of columns and the midspan of beams.

• A. Virtual work of the internal forces
• B. Total strain energy of the structure
• C. Kinetic energy of the moving loads
• D. Permanent deformation of the members

Explanation: Equilibrium requires the external virtual work to equal the internal virtual work for every compatible virtual displacement.

• A. A unit load at i with all coordinates free
• B. A unit displacement at i with other coordinates fixed
• C. A unit rotation at every coordinate
• D. A unit displacement at another coordinate with i fixed

Explanation: Kii is the restoring force or moment at coordinate i produced by imposing a unit displacement at the same coordinate while all other nodal…

• A. x/L
• B. x divided by L squared
• C. 1 minus x/L
• D. 1 minus x divided by L squared

Explanation: Equilibrium gives the left reaction as (L minus x) divided by L, which is 1 minus x/L.

• A. dV/dx = minus M squared
• B. dV/dx = M
• C. dM/dx = minus V squared
• D. dM/dx = V

Explanation: With the usual beam sign convention, the derivative of bending moment with respect to position equals the shear force, dM/dx = V.

• A. The calculated displacement must equal the prescribed displacement
• B. The released structure must remain completely rigid
• C. The redundant force must equal the support reaction
• D. The bending moment must vanish at every released coordinate

Explanation: The redundant forces are found by enforcing compatibility between the calculated and prescribed displacements.

• A. The force at coordinate j caused by unit displacement at i
• B. The force at coordinate i caused by unit displacement at j
• C. The displacement at coordinate i caused by unit force at j
• D. The total reaction caused by all applied joint loads

Explanation: Kij is the force developed at coordinate i when a unit displacement is imposed at coordinate j while the other restrained coordinates…

• A. Zero
• B. Two
• C. One
• D. Three

Explanation: There are three vertical support reactions but only two independent vertical equilibrium equations for the beam.

• A. Removal of bending moment at every rigid joint
• B. Reduction of dead load caused by material creep
• C. Increase in shear strength caused by axial compression
• D. Additional moment caused by axial load acting through lateral displacement

Explanation: When a compressive axial load acts through a laterally displaced position, it produces an additional moment, commonly written as P…