Abstract:

It has been confirmed from completely undrained tests that flow failure is triggered only in saturated contractive sands, while strain hardening or cyclic mobility happened in saturated dilative sands during an application of post-liquefaction monotonic or cyclic shearing. In practice, however, there exist different conditions of drainage in shearing, such as partial drainage and even water absorption initiated in saturated sands under pre- and post-liquefaction loading. Experimental facts show that the large flow deformation can be induced in dilative sands during a post-liquefaction shearing application, only when sufficient magnitude of water-absorption in shearing takes place. The occurrence of large flow deformation is found to depend mainly on a constraint requirement for developments and variations in three kinds of volumetric strain components of saturated sands. Such a constraint condition is also verified to govern different post-liquefaction stress-strain responses of dilative sands.

Key words: dilative sands, post-liquefaction flow failure, drainage condition, water-absorption in shearing