New Techniques in Deformability Testing of

Stabilization of Slopes Using Piles : Interim Report

“…Geologists overlook this value and prefer to use load-deformation curves to predict the deformation modulus or in-situ Young's Modulus, E , of the rock. (2) the tests can be performed at great depths; and, (3) large radial pressures can be applied (Rocha, 1970). Pressuremeter tests have also been used successfully in the past for the calculation of the modulus of soft rocks (Dixon, 1970).…”

Development of techniques for evaluating seismic hazards of creeping landslides and old dams

“…Design details, calibration procedures and loading patterns of existing dilatometers will be carefully compared and the best incorporated into this new design. The effects of drilling on the rock and stress field around boreholes will have to be evaluated; for example, Rocha (1969) suggested that dilatometric modulus might be higher than those measured from surface loading due to stress concentration around boreholes, but Charrua-Graca (1979) reported the opposite, Also, the interpretation of results with respect to strength and stresses need to be studied. The Pressuremeter provides information on both when used in soils and soft rocks; for hard rocks, theory developed by Ladanyi (1967) shows that ultimate borehole radial pressure is 6 to 10 times the unconfirmed compressive strength of the rock and depends on strength parameters, deformability parameters, and initial stress.…”

“…The effect of rock fracturing on the modulus of elasticity recorded by a dilatometer was considered by Rocha (1969). (Fig.…”