This set of Design of RC Structures Multiple Choice Questions & Answers (MCQs) focuses on “Foundations – General Rules of Design”.
1. What does the code (IS: 456 – 2000) recommends about the thickness at the edge of footing on soils?
a) Should not be less than 300 mm
b) Should not be less than 150 mm
c) Should not be less than 250 mm
d) Should not be less than 200 mm
View Answer
Explanation: For the reinforced and plain concrete footings, the thickness at edge should not be less than 150 mm for footings on soils. Also it should not be less than 300 mm above the tops of piles for footings on piles.
2. What is the expression to govern angle (α) between plane passing through the bottom edge of pedestal and the corresponding junction edge of the column?
a) (tanα) should not be less than 0.9 √[(100q0 / fck) + 1]
b) (tanα) should not be less than 1.0 √[(100q0 / fck) + 0.9]
c) (tanα) should not be less than 0.9 √[(10q0 / fck) + 1]
d) (tanα) should not be less than √[(100q0 / fck) + 1]
View Answer
Explanation: The angle (α) is between the plane passing through the bottom edge of pedestal and the corresponding junction of the column with pedestal. It is governed as (tanα) should not be less than:
0.9 √[(100q0 / fck) + 1]
Here (q0) is calculated maximum bearing pressure at the base of the pedestal.
(fck) is characteristic strength of concrete at 28 days.
3. The shear stress for footings is checked for one way action and two way action.
a) False
b) True
View Answer
Explanation: The critical section for checking development length in a footing is assumed at the places where bending moments is determined. It can also be considered at the change of section. So for this shear stress is checked for one way action or beam shear and two way action that is punching shear.
4. What is the value of shear stress (τv) for two way action?
a) F / [2[(a + d) – (b + d)]d]
b) F / [2[(a + d) + (b + d)]]
c) F / [[(a + d) + (b + d)]d]
d) F / [2[(a + d) + (b + d)]d]
View Answer
Explanation: For the two way action the expression for shear stress is:
τv = F / [2[(a + d) + (b + d)]d]
It should be less than or equal to kc.τc.
(F) is the net S.F. acting on the perimeter.
a, b and d are the dimensions of the column or pedestal.
5. What is the value of minimum nominal cover for footing?
a) 50 mm
b) 60 mm
c) 100 mm
d) 70 mm
View Answer
Explanation: Nominal cover is the design depth of concrete cover to all steel reinforcements, including links. It is the dimension used in design and indicated in the drawings. It shall not be less than the diameter of the bar. For footing minimum nominal cover should be 50 mm.
6. The total tensile reinforcement at any section should provide a moment of resistance more than bending moment on the section.
a) False
b) True
View Answer
Explanation: The total tensile reinforcement at any section should provide a moment of resistance. This should be at least equal to the bending moment on the section. The total tensile reinforcement should be distributed across the corresponding resisting section.
Sanfoundry Global Education & Learning Series – Design of RC Structures
To practice all areas of Design of RC Structures, here is complete set of 1000+ Multiple Choice Questions and Answers.
