软土地基处理沉降计算中相关参数的试验研究

通过粉喷桩、浆喷桩、真空联合堆载预压、塑料排水板超载预压及砂桩超载预压等方法处理高速铁路软土地基的现场试验,对其软基处理的压缩层厚度、侧向位移引起的沉降及其修正系数进行研究。结果表明:压缩层厚度采用应力比法?p/p0≤0.1为控制条件较合理。搅拌桩加固后,大为减小了地基总沉降。采用各种规范规定的沉降修正系数进行沉降计算的值均与实测值有一定差异,而采用国家规范的m值得出的沉降与实测推算的沉降相差最小。

Experimental Study on Related Parameters in Settlement Calculation of Soft Foundation

Through site test on high-speed railway soft foundation with dry jet mixing pile,deep jet mixing pile,vacuum preloading,plastic drain surcharge and sand pile surcharge,the settlement caused by compression layer thickness and lateral displacement as well as its correction factor are studied.The result shows that it is reasonable to use stress ratio method（△p/p0≤0.1） to calculate the thickness of compressed layer.Total settlement of foundation will be largely reduced by reinforcement of mixing pile.In addition,there is a certain difference between mean value calculated by correction factors specified by various standards and measured value.However,the settlement calculated by ＂m＂ value stipulated by national standard is closest to predicted value through actual measurement.