Abstract:
Because of their lightweight and highly crushable and compressible nature, pumiceous sands are problematic from engineering and construction viewpoints. There has been very little information on their liquefaction characteristics, and most empirical procedures available in evaluating the liquefaction potential of sands are derived primarily from hard-grained sands. To understand the undrained cyclic behavior of pumice sands, several series of undrained cyclic triaxial tests were performed on two sets of pumice samples. One set of samples consisted of undisturbed pumiceous deposits taken from a site in Waikato, whereas the other set involved reconstituted pumice sands in both loose and dense states. The results obtained were compared with those observed in Toyoura sand, a typical (hard-grained) sand. The degree of particle breakage in pumice during cyclic shearing was examined, highlighting the effect of the crushable nature of the grains on the cyclic response of the soil.