IN THE EQUATION

摘要

AS SOCIETIES CONTINUE TO grow and urbanize, major civil infrastructure projects are being constructed in increasingly complex geometries and at deeper horizons. Rockmass discontinuities regularly govern the material behaviour around engineering projects such as natural slopes, surface excavations, and underground openings (Figure 1). Geotechnical laboratory tests, such as direct shear, provide a means to determine stiffness, strength, and post-peak material properties, which are key parameters used to quantify rockmass behaviour. Direct shear tests are typically conducted under constant normal stress and constant normal load boundary conditions, which are considered to represent fracture behaviour in near surface gravity-driven environments. Both constant normal load and constant normal stress conditions allow the fracture to dilate freely during shear, so there is no feedback between dilation and normal stress.