During percussion drilling

caving or mixing of strata are caused in soft soils or cohesionless soils

the soil to a considerable depth below the bottom of the hole gets disturbed

ground water observations are hindered due to entry of the slurry in the soil below the bottom of the hole

All of the above

Correct Answer : All of the above

Recently Updated in Building Construction Questions

Depth of lean concrete bed placedat the bottom of a wall footing, is kept

10 cm

15 cm

equal to its projection beyond wall base

less than its projection beyond wall base

Correct Answer : Option (C) : equal to its projection beyond wall base

In ordinary residential and public buildings, the damp proof course is generally provided at

plinth level

ground level

water table level

midway ground level and watertable level.

Correct Answer : Option (A) : plinth level

In clay soil

swelling and shrinkage characteristics prevail

differential settlement is generally prevalent

consolidation continues even after several years of construction.

All of the above

Correct Answer : Option (D) : All of the above