Rail Vikas Nigam Civil Site Engineer Interview Questions and Answers

Bentonite is used as a drilling fluid to stabilize boreholes before pulsing.

• Bentonite is mixed with water to form a slurry and pumped into the borehole.

• The slurry fills the borehole and stabilizes the walls, preventing collapse.

• After the bentonite has set, pulsing can be done without the risk of borehole collapse.

• Pulsing is a technique used in geophysical exploration to measure the properties of the subsurface.

Compression test of concrete is a method to determine the compressive strength of concrete.

• A cylindrical sample of concrete is prepared and placed in a compression testing machine.

• The machine applies a load at a constant rate until the sample fails.

• The maximum load that the sample can bear before failure is recorded as the compressive strength of the concrete.

• The test is important to ensure the quality and durability o...read more