List of top Structural Engineering Questions

A post-tensioned concrete member of span 15 m and cross-section of 450 mm $\times$ 450 mm is prestressed with three steel tendons, each of cross-sectional area 200 mm$^2$. The tendons are tensioned one after another to a stress of 1500 MPa. All the tendons are straight and located at 125 mm from the bottom of the member. Assume the prestress to be the same in all tendons and the modular ratio to be 6. The average loss of prestress, due to elastic deformation of concrete, considering all three tendons is
An undamped spring-mass system with mass \( m \) and spring stiffness \( k \) is shown in the figure. The natural frequency and natural period of this system are \( \omega \) rad/s and \( T \) s, respectively. If the stiffness of the spring is doubled and the mass is halved, then the natural frequency and the natural period of the modified system, respectively, are
For the square steel beam cross-section shown in the figure, the shape factor about \(z - z\) axis is \(S\) and the plastic moment capacity is \(M_P\). Consider yield stress \(f_y = 250 \, \text{MPa}\) and \(a = 100 \, \text{mm}\). The values of \(S\) and \(M_P\) (rounded-off to one decimal place) are:
Read the following statements relating to flexure of reinforced concrete beams:
I. In over-reinforced sections, the failure strain in concrete reaches earlier than the yield strain in steel.
II. In under-reinforced sections, steel reaches yielding at a load lower than the load at which the concrete reaches failure strain.
III. Over-reinforced beams are recommended in practice as compared to the under-reinforced beams.
IV. In balanced sections, the concrete reaches failure strain earlier than the yield strain in tensile steel.
Each of the above statements is either True or False.
Which one of the following combinations is correct?
Match all the possible combinations between Column X (Cement compounds) and Column Y (Cement properties):
Which one of the following combinations is correct?
For a linear elastic and isotropic material, the correct relationship among Young's modulus of elasticity $(E)$, Poisson's ratio $(\nu)$, and shear modulus $(G)$ is:
Consider a beam PQ fixed at P, hinged at Q, and subjected to a load \( F \) as shown in the figure (not drawn to scale). The static and kinematic degrees of indeterminacy, respectively, are

A small project has 12 activities – N, P, Q, R, S, T, U, V, W, X, Y, and Z. The relationship among these activities and the duration of these activities are given in the table. 
 

The total float of the activity “V” (in weeks, in integer) is _______________

A square plate O-P-Q-R of a linear elastic material with sides 1.0 m is loaded in a state of plane stress. Under a given stress condition, the plate deforms to a new configuration O-P'-Q'-R' as shown in the figure (not to scale). Under the given deformation, the edges of the plate remain straight. 

The horizontal displacement of the point (0.5 m, 0.5 m) in the plate O-P-Q-R (in mm, round off to one decimal place) is \(\underline{\hspace{1cm}}\).

Employ stiffness matrix approach for the simply supported beam as shown in the figure to calculate unknown displacements/rotations. Take length, \( L = 8 \, \text{m} \); modulus of elasticity, \( E = 3 \times 10^4 \, \text{N/mm}^2 \); moment of inertia, \( I = 225 \times 10^6 \, \text{mm}^4 \). 

The mid-span deflection of the beam (in mm, round off to integer) under P = 100 kN in downward direction will be \(\underline{\hspace{1cm}}\)

A column is subjected to a total load \( P \) of 60 kN supported through a bracket connection, as shown in the figure (not to scale). 

The resultant force in bolt R (in kN, round off to one decimal place) is \(\underline{\hspace{1cm}}\).

A prismatic cantilever prestressed concrete beam of span length, \( L = 1.5 \, \text{m} \), has one straight tendon placed in the cross-section as shown in the following figure (not to scale). The total prestressing force of 50 kN in the tendon is applied at \( d_c = 50 \, \text{mm} \) from the top in the cross-section of width, \( b = 200 \, \text{mm} \) and depth, \( d = 300 \, \text{mm.}\) 
 

Refer the truss as shown in the figure (not to scale). 

\( \text{If load, } F = 10\sqrt{3} \, \text{kN}, \, \text{moment of inertia} \, I = 8.33 \times 10^6 \, \text{mm}^4, \, \text{area of cross-section} \, A = 10^4 \, \text{mm}^2, \, \text{and length} \, L = 2 \, \text{m} \text{ for all the members of the truss, the compressive stress (in kN/m}^2 \text{, in integer) carried by the member Q-R is \(\underline{\hspace{1cm}}\)}. \)

A wedge M and a block N are subjected to forces P and Q as shown in the figure. If force P is sufficiently large, then the block N can be raised. The weights of the wedge and the block are negligible compared to the forces P and Q. The coefficient of friction \( \mu \) along the inclined surface between the wedge and the block is 0.2. All other surfaces are frictionless. The wedge angle is 30°.

The limiting force \( P \), in terms of \( Q \), required for impending motion of block N to just move it in the upward direction is given as \( P = \alpha Q \). The value of the coefficient \( \alpha \) (round off to one decimal place) is:

A truss EFGH is shown in the figure, in which all the members have the same axial rigidity \( R \). In the figure, \( P \) is the magnitude of external horizontal forces acting at joints F and G. 

The state of stress in a deformable body is shown in the figure. Consider transformation of the stress from the \( x \)-\( y \) coordinate system to the \( X \)-\( Y \) coordinate system. The angle \( \theta \), locating the \( X \)-axis, is assumed to be positive when measured from the \( x \)-axis in counter-clockwise direction. 

 \[ \sigma_{xx} = 120 \, \text{MPa}, \sigma_{yy} = 40 \, \text{MPa}, \sigma_{xy} = 50 \, \text{MPa} \] The absolute magnitude of the shear stress component \( \sigma_{xy} \) (in MPa, rounded off to one decimal place) in the \( x \)-\( y \) coordinate system is \(\underline{\hspace{1cm}}\). 
 

The equation of deformation is derived to be \( y = x^2 - xL \) for a beam shown in the figure. 

A propped cantilever beam EF is subjected to a unit moving load as shown in the figure. The sign convention for positive shear force at the left and right sides of any section is also shown. 
 

The CORRECT qualitative nature of the influence line diagram for shear force at G is 

The direct and indirect costs estimated by a contractor for bidding a project are ₹160000 and ₹20000 respectively. If the mark-up applied is 10% of the bid price, the quoted price (in ₹) of the contractor is:
Gypsum is typically added in cement to:

A frame EFG is shown in the figure. All members are prismatic and have equal flexural rigidity. The member FG carries a uniformly distributed load \( w \) per unit length. Axial deformation of any member is neglected. 

Considering the joint F being rigid, the support reaction at G is:

A propped cantilever beam XY, with an internal hinge at the middle, is carrying a uniformly distributed load of 10 kN/m, as shown in the figure. 

The vertical reaction at support X (in kN, in integer) is \(\underline{\hspace{1cm}}\)

A solid circular torsional member OPQ is subjected to torsional moments as shown in the figure (not to scale). The yield shear strength of the constituent material is 160 MPa.
 

The absolute maximum shear stress in the member (in MPa, round off to one decimal place) is \(\underline{\hspace{1cm}}\).

In case of bids in Two-Envelope System, the correct option is
Seasoning of timber for use in construction is done essentially to