Effects of N-(n-butyl)thiphosphorothioate Triamine on the Mechanical Properties of Microbially Cured Sandy Soils
Through analyzing the mechanical property indexes and calcium carbonate content of microbiologically reinforced standard sand specimens to evaluate the effect of NBPT on MICP-reinforced sandy soils,and analyzing the microstructural characteristics of the cured specimens to reveal the mechanism of NBPT's action on MICP-reinforced sandy soils.The results showed that the stress-strain curves of microbial reinforced standard sand samples were all of the stress-softening type,NBPT was introduced into the sample micro-organisms induced to produce more calcium carbonate crystals,more uniform distribution of cemented soil particles and pore filling,macroscopically manifested as a denser sand sample,more difficult to be compressed,with a better mechanical properties.NBPT affects the size and morphology of calcium carbonate crystals induced by MICP,so that a small amount of small-sized calcium carbonate is generated at the early stage of the reac-tion,which avoids a large amount of generated calcium carbonate blocking the seepage paths,and the subsequent cement can be smoothly infused,and the cement can be fully utilized,and at the late stage of the reaction,a large amount of calcium carbonate can be generated.The subsequent cement can be infiltrated smoothly,the cement can be fully utilized and more calcium carbonate can be generated in the later stage of the reaction to fill the internal pores of the sand samples uniformly,which makes the soil denser and effectively improves the effect of soil reinforcement by MICP technology.
microbiotechnologyurease inhibitorstriaxial testscanning electron microscope
万方数据
