Introduce Flow table test. How can sulphate attack be controlled?
Flow Table Test:-
This is a laboratory test, which gives an indication of the quality of concrete with respect to consistency, cohesiveness and the proneness to segregation. In this test, a standard mass of concrete is subjecting to jolting. The spread or the flow of the concrete is measured and this flow is related to workability.
Sulphate attack can be controlled by:
Short notes on :
Discuss the role of Gel-space ratio. How can it be determined? Calculate the gel-space ratio and theoretical strength of a sample of concrete made with 500gm of cement with 0.5 w/c ratio on full hydration and 40% partial hydration. Discuss the factors which influence creep in concrete?
Design concrete mixes of M30 to suit the following data per IS:10262-1982 :
Characteristic cube strength = M-30, type of cement - ordinary Portland, fine aggregate natural river sand conforming to grading zone II of table-4 of IS:383-1970 coarse aggregate-crushed (angular) coarse aggregate of 20 mm maximum size conforming to IS:383 code requirements, specific gravities of cement, sand and coarse aggregate are 3·14, 2·63 and 2·61 respectively. Type of exposure - mild, Degree of quality control - very good. Degree of workability = 0·08. use IS:10262-1982.