IS 2720 : Part 35 : 1974 Methods of test for soils: Part 35 Measurement of negative pore water pressure

1. SCOPE

1.1 This standard ( Part XXXV) lays down the method for determining the negative pore water pressure in partially saturated soils. For pressures in the range of 0 to - 0'75 kg/cm2 the measurement can be obtained directly. For this range as well as for greater negative pressures, measurement is possible in soils in which air continuity exists and the measurement is achieved indirectly by the axis translation technique by artificially increasing pore air pressure and ambient pressure until pore water pressure is in the positive range. The maximum magnitude of the measurement thus possible is limited to the air entry value of the fine ceramic porous stone used.