Quiz: Civil Engineering
Each question carries 1 mark
Negative marking: 1/4 mark
Time: 10 Minutes
Q1. Los Angeles machine is used to test Aggregate_____
(a) Crushing strength
(b) Impact Value
(c) Abrasion resistance
(d) Water absorption
Q2. Alkalinity in water is expressed as mg/l; in terms of: –
(a) Calcium carbonate
(b) Magnesium carbonate
(c) Sodium carbonate
(d) Sodium bi-carbonate
Q3. When the degree of consolidation is 50% about how much is the time factor?
Q4. The thermal expansion coefficient (α) of steel is:
(a) 13×10^(-6/°C) and closely resembles to α of concrete.
(b) 11×10^(-6/°C) and differs widely from α of concrete
(c) 12×10^(-6/°C) and close to α of concrete.
(d) 14×10^(-6/°C) but nearly equal to α of concrete
Q5. Bolts are most suitable to carry-
(c) Axial tension
(d) Shear and bending
Q6. In some brick masonry walls, patches of whitish crystal were found on the exposed surfaces, also chipping and spalling of bricks took places from the same walls. Which among the following are the causes of these defects?
1. Settlement of foundation
2. Over-loading of the wall
3. Sulphate attack
(a) 1 and 2
(b) 2 and 3
(c) 2 and 4
(d) 3 and 4
Q7. The type of cement used in lining of deep tube wells is:
(a) Blast furnace slag cement
(b) Portland pozzolana cement
(c) Oil well cement
(d) High alumina cement
Q8. The length of a curve connecting two uniform gradients of +0.8% and -0.6%, the rate of change of grade being 0.1% per 30 m, will be
(a) 220 m
(b) 320 m
(c) 420 m
(d) 520 m
Q9. The ratio between adopted centrifugal ratios for roads and railways is
(a) 3 : 1
(b) 2 : 1
(c) 5 : 1
(d) 4 : 1
Q10. At a hydraulic jump, the depths at the two sides are 0.4 m and 1.4 m. The head loss in the jump is nearly?
(a) 1.0 m
(a) 0.9 m
(c) 0.7 m
(d) 0.45 m
Sol. Crushing Test → Gives crushing strength
Impact Test → Gives Toughness
Los Angeles Test → Gives Abrasion resistance or hardness.
Sol. Alkalinity in water is expressed as mg/l in terms of calcium carbonate.
Major ions → CO_3^(-2),HCO_3^-,OH^-
Minor ions → HS^-,H_2 PO_4^-,HPO_4^(-2) etc.
Sol. When %U < 60%
time factor (T_v )=π/4 (%U)^2
Sol. Coefficient of thermal expansion (α) for steel is 12×10^(-6)/°c
Coefficient of thermal expansion for Concrete is 6×10^(-6)/°c to 12×10^(-6)/°c
Sol. Bolts are more suitable to carry Axial tension.
– The patches of whitish crystal were found on the exposed surface is due to efflorescence.
– The chipping and spalling of bricks are due to sulphate attack.
Sol. Portland – Pozzolana cement (PPC) is used in lining of deep tube wells. It is manufactured by grinding OPC and Pozzolana (containing fly ash 10 to 25% by mass). It is also used in mass concreting and places of high temperature.
Length of curve =(0.8-(-0.6))/0.1 ×30
→ Maximum value of centrifugal ratio for roads = 1/4
→ Maximum value of centrifugal ratio for railways = 1/8
So, ratio between these two = (1/4)/(1/8)
= (2 : 1)
Sol. Given, conjugate depths y_1=0.4 m.
E_L=(y_2-y_1 )^3/(4y_1 y_2 )