Experimental Study on Shear Behaviour of Microbially Solidified Soil in Undrained Triaxial Tests
Microbially induced calcium carbonate precipitation is an efficient soil reinforcement technique,which is gradually applied in engineering because it can rapidly enhance the strength and stability of soil.To investigate the influence of confining pressure and calcium carbonate content on the mechanical properties of microbially solidified soil,different saturated microbially solidified soil samples with varying calcium carbonate contents are subjected to triaxial consolidated undrained shear strength tests under different confining pressures.The study aims to explore the stress-strain characteristics and pore water pressure-strain behavior of microbially solidified soil under different confining pressures and calcium carbonate content conditions,and analyzes the influence of calcium carbonate content on the initial tangent modulus,failure envelope,and critical state line.The relationship between calcium carbonate content and test parameters is established.The test results show that calcium carbonate can increase the peak strength of soil,and the filling effect of calcium carbonate leads to higher residual strength in microbially solidified soil compared to the residual strength of untreated soil.The effects of confining pressure and calcium carbonate on the pore water pressure-strain behavior exhibit distinct patterns.Increasing confining pressure results in larger axial strains corresponding to negative pore pressures,while with the increase of calcium carbonate content,the axial strains corresponding to negative pore pressures gradually decrease,indicating that microbially solidified soil is more prone to dilatancy.Failure envelope and critical state line both move upward with the increase of calcium carbonate content.
solidified soilcalcium carbonateshear strengthtangent modulusexperimental study
万方数据
维普
