Plate Load Test :-
1.Bearing Plate: - It is either circular or square made up mild steel of not less than 25mm thickness and varying in size from 300 to 750mm with grooved bottom. For clayey soil a
450mm square plate concrete block is used. In case of sandy soil three plates of size 300mm to 750mm depending upon loading.
2.Test Pit: - The test pit at foundation level should have width equal to five times the test plate and it should be cleaned and leveled at bottom. The test pit should have steps to continently go in to the pit for taking observation.
3.Loading Arrangement:- The loading may be applied with the help of hydraulic jack by any two methods a) Gravity loading Platform Method b) Reaction Truss Method.
4.Setting of Plate:- The test plate should be placed over fine sand layer having maximum thickness of 5mm. A minimum seating pressure of 70g/cm2 shall be applied and removed before starting the load test.
5.Load Increment: - Apply the load to soil in cumulative equal increment up to 1kg/cm2
one fifth of the estimated ultimate bearing capacity whichever is less.
6.Settlement and observation:- The settlement should be observed for each increment of load after an interval of 1, 2.25, 4, 6.25, 9, 16 and 25 minute and thereafter hourly interval to nearest 0.02mm. The test shall be continued till a settlement of 25mm in normal case and 50mm in special case or till the failure.
7.Loading Settlement Curve and Ultimate Bearing Capacity: - Load settlement curve is plotted where load intensity is on X axis and Settlement is on Y axis.