Correct Answer - Option 3 : Both bearing capacity and settlement of foundation
Plate load test:
Plate load test is performed to determine soil bearing capacity and settlement.
It is a semi-direct method to measure the allowable pressure of soil by inducing a given amount of settlement. The load on the plate is applied by making use of a hydraulic jack. The reaction of the jack load is taken by a cross beam or a steel truss anchored suitably at both the ends. The settlement of the plate is measured by a set of three dial gauges of sensitivity 0.02 mm placed at 120° apart. The dial gauges are fixed to independent supports which do not get disturbed during the test.
Shape and size of the plate load test are given below:
- Square or circular in shape
- Thickness > = 25 mm
- Size may vary from 300 to 750 mm. therefore, the maximum size is 750 mm
- For clayey and silty soils and for loose to medium dense sandy soils with N < 15, 450 mm square plate is used
- For dense sandy or gravelly soils(15 < N < 30) three plates of sizes 300 mm to 750 mm is used depending on reaction loading and maximum grain size
- Side of plate = 4 × size of particles
