Concrete Technology(Special Set-1)

Rapid-hardening cement is used in

• (a) pre-fabrication concrete construction

• (b) road repair work

• (c) extreme cold weather    

• (d) all above these

According to IS:383-1970, number of zones available for fine aggregate is –

• (a ) 1

• (b) 2  

• (c) 3

• (d) 4

Aggregate retained on 4.75 mm sieve called

• (a) fine aggregate

• (b) coarse aggregate

• (c) both a & b

• (d) none of these

Approximate % of CaO in OPC is-

• (a) 40 – 55  

• (b) 60 – 67

•  (c) 15 – 22

• (d) 10 – 15

As per IS:456-2000, pH value of water used for concrete making –

• (a ) shall not be less than 6

• (b) shall not be more than 6

• (c) shall not be less than 5

• (d) none of these

Standard consistency test conducted to find-

• (a) initial setting time of cement

• (b) final setting time of cement

• (c) soundness of cement

• (d) both a & b

REDISET cement allows a handling time of-

• (a) 8 to 10 minutes

• (b) 10 to 15 minutes

• (c) 20 to 30 minutes

• (d) none of these

Quartzite is a -  

• (a) igneous rock

• (b) sedimentary rock

• (c) metamorphic rock

• (d) none of these

As per IS:456-2000 the permissible limit of sulphates in water used for making concrete is

• ( a) 200 ppm

• (b) 3000 ppm

• (c) 400 ppm

• (d) 2000 ppm

For fineness test of cement by seiving, standard IS sieve used of size-

• (a) 70 microns

• (b) 75 microns

• (c) 90 microns

• (d) 80 microns