260.  Which one of the following materials is used as a bonding admixture
A. natural rubber
B. synthetic rubber
C. organic polymers
D. All of these

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261.  Pick up the correct dimensions of the mould for slump test from the following:(Top-Bottom diameter-Height diameter)
A. 10-20-30
B. 20-30-10
C. 30-10-20
D. 20-30-40

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262.  Pick up the correct statement from the following: Drying shrinkage is affected by
A. the relative humidity of the atfriosphere when the concrete is placed
B. the length of time
C. the water/cement ratio of the concrete
D. All the above

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263.  No shrinkage occurs if the concrete is placed in a relative humidity of
A. 100 percent
B. 85 percent
C. 70 percent
D. 50 percent

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264.  Pick upthe correct statement from the following:
A. Density of normal concrete is about 2400 kg per cubic metre
B. Density of light weight concrete is about 1900 kg per cubic metre
C. Density of heavy concrete is about 3850 kg per cubic metre
D. All the above

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265.  For the construction of radiation shields, which one of the following concretes is preferred?
A. normal concrete
B.1 jilt weight concrete
C. heavy weight concrete
D. None of these

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266.  Consider the following statements regarding the importance of compound composition of cement : 1 Tri calcium silicate is most important 2 Di calcium silicate is most important 3 Tetracalcium alumino ferrite is most important of these statements :
A. 1 slone is correct
B. 1 and 2 are correct
C. 2 alone is correct
D. 3 alone is correct

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