A METHOD FOR DETERMINATION OF PHI(B) FOR STATICALLY COMPACTED SOILS

The unsaturated shear strength parameter, phi(b), is usually determine d using triaxial or direct shear apparatus that have been modified to allow for the control and (or) measurement of pore-air and pore-water pressures. A fairly high level of expertise is required for the charac terization of phi(b) using these modified apparatus. A simple procedur e for determining phi(b) for statically compacted soils at different w ater contents is presented along with a method of analysis. The tests can be performed on a conventional direct shear apparatus. The unsatur ated shear strength parameter, phi(b), obtained using the proposed pro cedure is shown to be comparable to that obtained using the modified d irect shear test. Since the proposed procedure utilizes standard labor atory direct shear equipment and takes a relatively short time to comp lete, it offers an easy and convenient alternative for the determinati on of phi(b) for statically compacted soils.