When conducting triaxial tests on soil samples, it is observed that due to internal pressure, the cell expands, soil specimen consolidates resulting in the change of volume change Gauge is therefore devised to accurately measure volume changes.

 

This is measured by observing the quantity of water entering or leaving the cell as the cell pressure and axial load are changed it is achieved by the displacement of free surface between the water supplied to the cell and another fluid Paraffin of kerosene

 

It is designed to determine the swelling pressure developed by soil specimens moulded to desired densities at known moisture contents, when soaked in water. The load applied to restrain the swelling is transferred on to a load measuring proving ring through a perforated swell plate and a load transfer bar. The proving ring is attached to the lead screw of hand operated load frame. A soaking tank is provided for saturating the specimen and the base of the mould provided has channels and radial grooves with connecting holes. 

 

The C.B.R. Method is used for finding the relative bearing ratio and expansion characteristics of soil of base, sub-base and sub-grade for the design of roads, pavements and runways.

 

Test can be made on all types of soils including sand, gravel, crushed stone etc. (Passing through 20mm IS sieve) C.B.R. test is used extensively for selection of materials and control of sub-grades. The procedure of test is very simple. A 50mm dia. penetration piston is forced in the test soilandloads required for the penetration to penetrate different depths are recorded by means of a proving ring fixed to the penetration piston assembly and a dial gauge. 

 

A Plate Bearing Testis a model test used for foundations. It is used to determine the ultimate bearing capacity of the foundations by providing the load deformation characteristics. It is a standard defined technique used to determine the bearing capacity of the solid which is calibrated and compared with the results of the other method against the values of the plate bearing test. In this test, a gradual increment of load is applied on the steel plate and the respective corresponding settlement is captured. The ultimate 50 ton bearing capacity is taken as the load up to which the settlement increases at a rapid rate with separate pumping. Plate Bearing Test unit fixed to it a 0-500KN x 0.5KN. 1No. Pressure gauge and flexible metal pipe 5 mtr. long 1No. Ball and socket arrangement between the jack and the bearing plate 1 No and extension rod 12mm dia x 25 cm long for taking dial gauge readings 16 Nos. Magnetic base with female thread on top for holding extension rod 4 Nos and end plate, 50mm, dia with male thread for fitting onto the extension rods and positioning the dial gauge plunger 4 Nos. 30 cms x 25mm.