Civil Engineer most asked interview Questions

How do you construct a 10 storey building with no columns ?

we can construct a 10 storey building by adopting shear walls instead of constructing columns.

What is Compressive Strength / Concrete grades?

Ans : The strength of concrete is designated as the Characteristic compressive strength of 150 mm cube at the age of 28 days when tested with the universal testing machine in N/ mm ².
As grades of concrete vary between 15 to 80 N/mm ². These grades differ on the basis of mix proportions.

A good concrete should not fall under less than 5% of desired concrete strength. We know that M 20 grade concrete has a compressive strength of 20 N/ mm ². A good concrete should not show less than 19 N/ mm ² (5%) of compressive strength when tested with UTM after 28 days

What is creep & shrinkage of concrete?

Shrinkage is Volumetric change in concrete due to loss of moisture content and lead to crack.

Creep. When concrete is subjected to compressive loading it deforms instantaneously. This immediate deformation is called instantaneous strain. Now, if the load is maintained for a considerable period of time, concrete undergoes additional deformations even without any increase in the load. This time-dependent strain is termed as creep.

What is a benchmark?

Bench mark is the permanent point of reference whose elevation with respect to assumed datum

What is the L/D ratio of a cantilever beam?

IS 456: 2000 prescribed a limiting value of l/d=7 for cantilever beams for spans up to 10m.

So, if we go beyond a certain length, we will end up with large depth as per the relation: d=l/7.

1. For cantilever beam = 7
2. Simply Supported Beam = 20
3. Continuous beam = 26
4. For spans > 10 m
5. For continuous beam =(10/span)*26

 What is meant by 80/100 grade bitumen?

80/100 is the softest of all . Based on the penetration values, bitumen can be graded as 80/100, 60/70 or 30/40 . It is suitable for low volume roads and is widely used in our country. With respect to viscosity, it is commonly known as VG-10.

How much is the cover for the slab?

As per specification of IS:456–2000, the minimum cover for slab is to be 20 mm which may vary up to 40 mm on the basis of fire resistance criteria.

What is differential settlement?

Differential settlement occurs when the soil beneath the structure expands, contracts or shifts away

 What is buckling or crippling load?

Buckling is characterized by a sudden sideways failure of a structural member subjected to high compressive stress ,  where the compressive stress at the point of failure is less than the  ultimate compressive stress that the material

What is the minimum curing time for cement concrete?

Curing period at temperatures above 5º C should be a minimum of 7 days or until 70% of the specified compressive or flexural strength is attained. The period could be reduced to 3 days if high early strength concrete is used and the temperature is above 10º C.

How to increase the bearing capacity of soil ?

The following techniques can be used for improving bearing capacity of soil as per the site condition.

1. Increasing depth of foundation
2. Draining the soil
3. Compacting the soil
4. Confining the soil
5. Replacing the poor soil
6. Using grouting material
7. Stabilizing the soil with chemicals