Question Paper: Concrete Technology : Question Paper May 2014 - Civil Engineering (Semester 4) | Gujarat Technological University (GTU)
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## Concrete Technology - May 2014

### Civil Engineering (Semester 4)

TOTAL MARKS:
TOTAL TIME: HOURS

1 (a) Enlist the types of cements and explain properties of PPC.(7 marks) 1 (b) Define standard consistency of cement and write the laboratory procedure for determining the same.(7 marks) 2 (a) Define initial setting time and final setting time of cement and explain the laboratory test for the same. Mention the IS limits of IST and FST of OPC.(7 marks) 2 (b) Give difference between Rapid hardening cement and Quick setting cement.(7 marks) 2 (c) Explain heat of hydration and it's importance in setting.(7 marks) 3 (a) Define aggregate and classify them according to (i) size (ii) Shape (iii) source of origin and (iv) Weight criteria.(7 marks) 3 (b) Define fineness modulus of aggregate and calculate it's value for the following test result. Explain it's utility.

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 IS sieve 40 20 10 4.75 2.36 1.18 0.6 0.3 0.15 % wt. Retained 5 30 50 60 80 96 99 100 100 % Passing 95 70 50 40 20 4 1 0 0
(7 marks) 3 (c) Describe effect of impurities in water on properties of concrete.(7 marks) 3 (d) Enlist the purposes of using admixture in concrete.(7 marks) 4 (a) Define workability of concrete and explain any one test to measure the workability of concrete.(7 marks) 4 (b) Explain segregation and bleeding phenomenon. Also write the causes of Segregation.(7 marks) 4 (c) Define the "Mix design" and design concrete mix M20 using following data and IS : 10262 procedure.
1. Max. size of aggregate = 20 mm
2. Degree of workability = 0.80 CF
3. Degree of quality control = good
4. Type of exposure = mild
5. w/c/ = 0.47
6. Cement used = OPC 53 grade
7. Sp. Gravity of cement =3.15, Coarse aggregate = 2.70, Fine aggregate =2.65
8. Water absorption of Coarse aggregate = 0.5 %, Fine aggregate = 1.0 %
9. Free moisture in C. A. = 0.0 % , F. A. = 0.0 %
10. Bulk density of Cement = 1440, C. A. = 1650, F.A. = 1800 kg/m3
(7 marks)
5 (a) Write note on NDT and it's utility(7 marks) 5 (b) Write note on (i) Hot weather concreting (ii) Recycled aggregate concrete.(7 marks) 5 (c) State causes and precautions for distress in structures.(7 marks) 5 (d) Explain with sketch crack repair by injection grouting.(7 marks)