Which one of the following tests is carried out using a relatively large diameter plate to evaluate the load supporting capacity of pavement layers? 

Explanation:

Plate load test/Plate bearing 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