SSC JE Civil Engineering 23-Mar-2021 Shift 1 Paper

Question : 146 of 200

Marks: +1, -0

As per IS 1742-1983, normally a sewer shall be designed for discharging _______ times the dry-weather flow flowing half-full with a minimum self-cleansing velocity of _______.

Five; 2.4 m/s
Three; 0.75 m/s
Four; 1.75 m/s
Two; 0.5 m/s

Validate

Solution:

Concept:
IS 1742-1983: Code of practice for building drainage
Normally, the sewer shall be designed for discharging three times the dry-weather flow flowing half-full with a minimum self-cleansing velocity of 0.75 m/s. The approximate gradients which give this velocity for the sizes of pipes likely to be used in building drainage and the corresponding discharges when flowing half-full are as follows:

Diameter(mm)	Gradients	Discharge ( $\m^3$ /min)
100	1 in 57	0.18
150	1 in 100	0.42
200	1 in 145	0.73
230	1 in 175	0.93
250	1 in 195	1.10
300	1 in 250	1.70

Go to Question:

Prev Question

Next Question