A field evaluation of the TRL load cell pressuremeter has been carried out to assess its performance in Gault Clay. The particular features of this self-boring pressuremeter are the use of six `null sensing' load cells and six piezometers equi-spaced around its circumference for the measurement of insitu total lateral stress and porewater pressure respectively. The instrument gives a direct reading of total stresses and, unlike the expansion pressuremeter, the results do not have to be derived from strain arm data by a skilled analyst. Because the pressuremeter is direct reading, the stresses and porewater pressures can be continuously monitored on site until they are fully stable. A test duration of about 16 hours was found to be generally appropriate for the Gault Clay. The results from the test borehole were compared with those obtained when using the expansion pressuremeter at the same site. (A)
Samenvatting