Quiz: Civil Engineering
Each question carries 2 marks
Negative marking: 1/3 mark
Time: 12 Minutes
Q1. A fine – grained soil has 60% (by weight) silt content. The soil behaves as semi-solid when water content is between 15% and 28%. The soil behaves fluid-like when the water content is more than 40%. The ‘Activity’ of the soil is
Q2. A mild steel specimen is under uniaxial tensile stress. Young’s modulus and yield stress for mild steel are 2 × 10^5 MPa and 250 MPa respectively. The maximum amount of strain energy per unit volume that can be stored in this specimen without permanent set is
(a) 156 N-mm/mm³
(b) 15.6 N-mm/mm³
(c) 1.56 N-mm/mm³
(d) 0.156 N-mm/mm³
Q3. The maximum super elevation to be provided on a road curve 1 in 15. If the rate of change of super-elevation is specified as 1 in 120 and the road width is 8m, then the minimum length of the transition curve on each end will be –
(a) 64 m.
(b) 80 m.
(c) 100 m.
(d) 120 m.
Q4. The water flow fully through the rectangular channel of latrel dimensions 5m × 4m. what is the velocity of flow (m/sec) through the channel, if the slope of energy line and Chezy’s constant as 0.0006 and 90 respectively?
Q5. The appropriate expression in assessing development length is
(b) L_d=σ_S/(4 τ_bd )
(c) L_d=(ϕσ_s)/〖8 τ〗_bd
(d) L_d=(ϕσ_s)/〖4 τ〗_bd
Activity (A_T )= ?
% Clay fraction finer than 2μ = 40%
〖Plasticity index (I〗_P) = w_L-w_P
= 40 – 28
A_T=I_P/(% Clay fraction finer than 2 μ)
E = 2 × 10^5 MPa
σ_y = 250 MPa
U = ?
Strain energy per unit volume is given by →
U=1/2 (σ_y )^2/E
Super elevation (e) = 1 in 15
Rate of change of super elevation (1 in N) = (1 in 120)
Width of road (w) = 8m.
Length of transition curve based on the rate of change of super elevation is
Sol. velocity of flow (v) = C√RS
C = Chezy’s constant = 90
R = hydraulic radius = A/P
Sol. As per IS : 456 – 2000, the development length (L_d) is given by
Where ϕ = diameter of bar in mm.
τ_bd = Bond stress in N/mm²
σ_s = stress in bar