Top 30 Technical Interview question for civil site engineers

What is the Tension and Compression zone in Cantilever Beam?

In Cantilever Beam, the Tension zone is located above the Neutral Axis and the Compression zone is located below the Neutral Axis.

• What is least cover provided for different RCC Members?

• Footing = 50 mm
• Column = 40mm
• Beam = 25mm
• Slab = 20mm

Which grade of concrete is considered as HSC (High Strength Concrete)?

 As per IS 456: 2000 [Table – 2], the grade of concrete considered as HSC (High Strength Concrete) is M65, M70, M75, M80, M85, M90, M95, and M100.

What are the functions of column in a building?

Column is a verticle member in building whose primary function is to support structural load and transfer it through beams. Upper columns transfers the load to the lower columns and finally to the ground through footings.

What is the cement sand & aggregate ratios for various grades of concrete mix?

• M10 – 1:3:6
• M15 – 1:2:4
• M20 – 1:1.5:3
• M25 – 1:1:2
• M30 – 1:1:1

What do you mean by honeycomb in concrete?

Honeycomb, also known as airpocket, is nothing but the air voids in concrete. It is usually formed during concrete casting.

Why should pumping be not used in case of concreting works?

During the pumping operation the pump exerted pressure must overcome any friction between the pumping pipes and the concrete, also the weight of the concrete and the pressure head when the concrete is placed above the pumps. Since only water is pump able, all the pressure generated is by the water that is present in the concrete. The major problem due to pumping are segregation effects and bleeding. In order to rectify and reduce these effects, generally the proportion of the cement is increased in order to increase the cohesion , which leads to the reduction of segregation and bleeding. Also if a proper selection of the aggregate grading can vastly improve the concrete pump ability.

What is the number of concrete cube samples taken for 6-15 cubic meter concrete?

As per IS 456: 2000 [Clause – 15.2.2], the number of concrete cube samples taken for 6-15 cubic meter concrete is 2, which consists of 6 concrete cubes.

 1 samples = 3 test specimens = 3 concrete cube

Does Water damage concrete?

Plain concrete is not affected or damaged by water but Reinforced Concrete (RCC) can be damaged due to water. This is because the water may seep into the concrete and corrode the steel reinforcement inside.

What is the initial and final setting time of ideal cement mix?

Initial setting time for ideal cement mix is around 30 minutes for almost all kind of cements. For masonry cement it can be 90minutes. Final setting time of ideal cement mix should be 10 hours at max. For masonry cement it shouldn’t exceed 24hours.

What is Anchorage Length?

As per IS Code 13920: 2016, Clause – 6.2.5, Anchorage length equals to development length of the bar in tension and plus 10 times bar diameter minus the allowance for 90 degrees bend.

What are common methods of curing the concrete?

• Spraying
• Wet covering of Surface
• Ponding
• Application of curing chemicals
• Steam curing

What is the formula for weight of steel?

Weight of steel in kg can be calculate by formula (D²*L)/162; where D is diameter of steel bar in millimeter and L is total length of steel bar in meter.

What do you know about “TMT”?

TMT stands for “Thermo Mechanically Treated”. Generally we use TMT bars and sheet for construction purposes for the reason that they have high strength and high corrosion resistance compared to normal steels.

What is the standard Diameter of Tremie Pipe?

 As per IS 456: 2000 [Clause – 14.2.4(a)], The tremie pipe shall be not less than 200 mm in diameter and shall be large enough to allow a free flow of concrete and strong enough to withstand the external pressure of the water in which it is suspended, even if a partial vacuum develops inside the pipe.

What is difference between working stress method and limit state method?

Working stress method is an elastic design method in which structure is designed to bear the load upto elastic limit. Whereas, limit state method is a plastic design method in which structure is designed to bear the load beyond plastic limit.

What should be the spacing considered when we use coupler in a longitudinal reinforcement bar?

 As per IS Code 13920: 2016, Clause – 6.2.6.2 (b), The spacing between adjacent longitudinal bars shall be based also on the outer size of the coupler to allow easy flow of concrete.

What field tests are required for quality check of cement?

Quality of cement can be checked with color, physical properties, etc. Cement should have grey color with light greenish shade. It should feel smooth when rubbed between fingers. If hand is inserted in a heap of cement or its bags, it should feel cool. When pinch of cement is thrown in Water then cement should float for some time before it sink. Also, it should be lump free.

What are the types of foundation used in construction?

There are basically two types of foundation: Shallow & Deep foundation. Again shallow foundation can be classified as spread footing, combined footing, strap or cantilever footing and finally mat or raft footing. Deep foundations can be classified as pile footing, pier footing, caissons footing and well foundation.

What are the types of cement?

There are various types of cement which are: Ordinary Portland Cement (OPC), White Portland Cement (WPC), Portland Pozzolana Cement (PPC), Low Heat Portland Cement, Coloured Portland Cement, Hydrophobic cement, Rapid Hardening Cement, Portland Slag Cement, Sulphate resisting Portland Cement, etc.

• Cement consumption for neat cement putting work (Ghola marna)– You must know these terms as a Billing engineers. And the Consumption -4.4 kg per square meter.
• Allowable wastage limit of steel for reconciliation – for this you must know the CPWD norms. Know how to control the Consumption and control the wastage. According to the CPWD only 2 % Wastage, But if I have giving responsibility as a billing engineer then I will keep no wastage record.
• Mode of measurement steel of BBS– Measure in running meter.
• Mode of measurement of Floor skirting- In running meter Given in Is code 1200 part-11
• Criteria for additional claim in plaster- above 10 m (Given in IS 1200 Part-12 CPWD)
• What is the standard length for hook in stirrups/rings?- According to IS code 2502: 1987 standard size of hook should be 24D for both ending while hook of 135 degree bends
• Minimum length of the bar shall not consider in wastage– 1 m or More

• Criteria of deduction in flooring work measurement– This kind of question generally asked as when contractor and client come to measure flooring work, know the standard size deduction should not be consider if less than 0.2 square meter according to the IS 1200. 
• How much binding wire required for binding steels– they will ask you such kind of question so you have to give the suitable considerable answers? Like 1 % of total reinforcement.
• Cement Consumption for 12 mm thick plaster in 1:4 Mortar Ratio-5.47 Kg/sq m (Given in CPWD)
• Allowable wastage limit of coarse aggregate and the fine aggregate -5 %.
• Mode of measurement t of anti-termite treatment work -in square meter.

What is guniting?

It is a process in which mixture of cement & sand in proportion of 1:3 is shooted on concrete surface with the help of cement gun under pressure of 2 to 3 kg/cm². It is a highly effective process for repairing concrete walls or damaged surfaces.

What is the function of sand in mortar?

The main role of sand (aggregate) in mortar or plaster is to provide core strength, but it has other benefits too. If water is mixed with binder without adding sand to the mixture, both compressive and tensile strength of the mixture would be drastically lower than in mixture with added sand. It also helps to prevent mortar shrinkage, increases density and helps in setting.

What are various tests for checking brick quality?

We can use water absorption test, hardness test, shape & size, crushing strength test, soundness test, etc. to check the brick quality. In water absorption test, we dip the brick for 16 hours in water. If weight of brick after dipping in water doesn’t exceed by 20%, it can be considered as first class brick, if below 22.5% it can be considered as second class brick, if below 25% it can be considered as third class brick. In crushing test, it crushing strength should be minimum of 10 N/mm² for first class brick, 7.5 N/mm² for second class bricks. In hardness test, we scratch the brick with nails. It should be scratch free. In soundness test we check the metallic sound by striking two bricks with each other.

What is RERA?

As per the Real Estate (Regulation & Development) Act, 2016 – Real Estate Regulatory Authority (RERA) would regulate and promote the real estate sector. The RERA will –

• Ensure the sale of land or building or a project in an efficient and transparent manner

• Protect the interests of consumers/buyers

• Establish an Appellate Tribunal mechanism to ensure speedy redressal of disputes

• Covers both residential and commercial projects

What is void ratio?

Void ratio is the ratio of volume of voids to volume of solids.

The civil engineering interview questions asked above are useful knowledge required in day-to-day work on field as a site engineer. Hence, it is vital to have sound knowledge of these basic questions.