脲酶诱导碳酸钙沉积固化砂土液化阻力研究

Study on the Liquefaction Resistance of Aeolian Soil Solidified by Enzyme Induced Carbonate Precipitation

摘要: 饱和砂土地基在振动荷载作用下易发生液化现象，地基加固是提高其稳定性与抗液化能力的关键措施。本文对EICP固化饱和砂土开展循环荷载作用下的三轴固结不排水剪切试验，分析围压、胶结次数、循环应力比及振动频率等因素对固化砂土抗液化性能的影响。研究结果表明：随着围压、胶结次数及干密度的增加，EICP固化砂土的动应变与滞回曲线面积逐渐减小，有效应力路径曲线越密实，EICP固化砂土达到液化时所需振动次数逐渐增加，其液化阻力逐渐提高。随着循环应力比与振动频率的增加，滞回曲线面积逐渐增大，有效应力路径向左移动速率增加，试样达到液化时所需振次逐渐降低，抗液化能力减弱。

Abstract: Saturated sandy soil foundation is prone to liquefaction under vibration loads, and foundation reinforcement is a key measure to improve its stability and resistance to liquefaction. This article conducts triaxial consolidation undrained shear tests on EICP solidified saturated sand under cyclic loading, analyzing the effects of confining pressure, bonding frequency, cyclic stress ratio, and vibration frequency on the liquefaction resistance of solidified sand. The research results indicate that with the increase of confining pressure, bonding frequency, and dry density, the dynamic strain and hysteresis curve area of solidified sand gradually decrease, the effective stress path curve becomes denser, and the required vibration frequency for solidified sand to reach liquefaction gradually increases, and its liquefaction resistance gradually increases. As the cyclic stress ratio and vibration frequency increase, the hysteresis curve area gradually increases, and the effective stress path moves to the left at an increased rate, resulting in a gradual decrease in the required number of vibrations for the sample to reach liquefaction and a weakening of its anti liquefaction ability.