QA QC Civil Engineer Interview Questions and Answers

1. What is Concrete Mix Design? (Select a fixed proportion of the ingredients) 

 2. What is the Water Cement ratio (ratio of the quantity of mixing water to the amount of cement) 

 3. The property of the ingredients to separate from each other while placing the concrete is called – Segregation. 

 4. What happens when the water-cement ratio increase ( Concrete become less workable, high slumps but strength decrease) 

 5. The standard sand now used in India is Obtained from Which Place?- Ennor (Chennai). 

 6. How would you Define the Workability of the Concrete?- Ease with which it can be Mixed, Transport and Placed in Position in Homogeneous state.

7. The factor which affects the design of concrete mix is?- Fineness modulus, water-cement ratio, and slump value. 

8. What happens when the water-cement ratio decreases? (because of the lower water content-concrete become drier, but compressive strength decreases) 

9. Which IS Code is following for concrete Mix design?-IS-10262 

10. How is the water to cement ratio determined? (By calculating the total weight of water to the importance of cement) 

11. The density of cement in Kg/m3 -1440 6. 

12. Setting time of gypsum increases by adding?- Gypsum 

13. What is the effect of air voids in concrete? (make the concrete more porous and hence strength is reduced highly) 

14. What is the smallest and largest Coarse aggregate used for RCC mix Design? (Largest Size=20mm, Smallest Size=10 mm) 

15. What is the effect of Increased size of Coarse Aggregate on Concrete Mix Design (if it is more than the design size, it affects the workability and causes segregation) 

 16. Is binding wire specification on-site?-minimum SWG (Standard wire gauge or 1.22 mm) soft annealed steel wire. 

 17. How many days Curing shall continue? – 7 days from the date of placing concrete in case of OPC. And should not be less than ten days for concrete exposed to dry and hot weather conditions. 

 18. Generally, What percentage of admixture is added in the mix? –less than or equal to 5 % by mass of the cement.