关键词: 泥石流沉积物; 固结特性; 微生物矿化碳酸钙; 排水固结试验; 载荷试验;

Abstract: Aiming at the high compressibility, low bearing capacity and slow consolidation of debris flow sediment, Bacillus pasteurized bacteria can be added to deposit calcium carbonate in the pore of debris flow.In order to explore the influence of microbial induced calcium carbonate precipitation(MICP)on the consolidation speed and bearing characteristics of debris flow sediment, 4 groups of debris flow sediment samples of 0.88Pa·s were prepared indoor.Three groups were inoculated with Bacillus pasteurized bacteria as experimental groups, and one group was not added anything as control group.The drainage consolidation test was carried out to observe the effect of adding bacteria liquid on drainage, settlement and pore water pressure of debris flow sediment, and then the load test was carried out to observe the change of bearing capacity.The research results showed that:(1) MICP could improve the bearing capacity of debris flow sediment, the proportional limit and limit bearing capacity of the test group increased about 20%on average;(2) MICP was unfavorable to the pore water pressure dissipation during debris flow sediment consolidation, especially when the porosity of viscosity debris flow was small.

Key words: debris flow sediment; consolidation characteristic; MICP; drainage consolidation test; load test;