Unconsolidated Undrained Triaxial Test Procedure

2 we need to test at least three samples at different confining pressure to obtain the mohr coulobm failure circles.

Unconsolidated undrained triaxial test procedure. The soil specimen in rubber membrane is mounted on the pedestal of the triaxial cell and fixed in position with the help of o rings. Triaxial shear test procedure 1. The triaxial cell is fixed to its bottom. In saturated soils the void.

In the last stage the sample is sheared to failure. In an unconsolidated undrained test the loads are applied quickly and the sample is not allowed to consolidate during the test. Uu unconsolidated undrained test is type of triaxial test. 1 the confining pressure is not zero.

Consolidated undrained test unlike the. Unconsolidated undrained uu test. Consolidated undrained test cu here during the application of cell pressure on the sample drainage is permitted. Uu triaxial tests commonly do not have a saturation or consolidation stage performed.

Unconsolidated undrained test in the unconsolidated undrained shear test the sample of soil is subjected to pressure. This allows the undrained shear strength c uto be determined which is suitable for assessing soil stability in the short term e g. The unconsolidated undrained uu test is the simplest and fastest procedure with soil specimens loaded whilst only total stresses are controlled and recorded. The soil specimen is enclosed in the rubber membrane to prevent entry of cell fluid into the voids of the soil specimen.

Unconsolidated undrained uu consolidated drained cd and consolidated undrained cu compression tests can be automatically run controlled and reported using this apparatus. The utest triaxial test system provides automated triaxial compression tests on cylindrical undisturbed and remolded soil samples. Solids discs are used to conduct undrained test. The confining pressure is applied followed immediately by the axial stress.

The test procedure of the triaxial shear strength of soil can be divided into three main types which are explained as follows. During or directly following a construction project. The test normally only consists of a shear stage. The third type of triaxial test is the unconsolidated undrained test uu test.

3 this is also a quick test as it is undrained. No drainage of the specimen is permitted during the application of the confining fluid pressure or during the compression phase of the test. Unconsolidated undrained test uu as the name tells the soil sample is subjected to cell pressure with no provision. This procedure differs from the others in that drainage is not allowed at any time and therefore no consoli dation till es place.

The sample is compressed at a constant rate strain controlled. The specimen is axially loaded at a constant rate of axial deformation strain controlled.