基于双曲线法的人工填土地基超载预压卸载时间的试验研究

基于中石油云南某石化装卸场铁路专用线人工填土地基堆载预压大型现场试验,采用双曲线法对试验段实测沉降数据进行拟合,分析双曲线方程参数与堆载高度之间的关系,利用反分析法得到地基沉降系数并对工后沉降进行修正,以确定超载预压下人工填土地基合理卸载时间。分析结果表明:采用双曲线法对试验段沉降观测数据进行拟合时,曲线参数β与堆载高度h呈负线性相关;由工后沉降修正得到的卸载时间随超载比的增大呈幂指数减少趋势,而超载比达到1.5(堆载高度9 m)后基本不再变化,此时满足规范要求的卸载时间最少为

Experimental Research on Foundation Preloading Unloading Time of Artificial Filled Soil Foundation Based on Hyperbolic Method

Based on large field test of artificial filled soil foundation preloading in a special railway line for petrochemical products loading and loading of CNPC in Yunnan province, the hyperbolic method is used for fitting the measured settlement data on the test section, the relationship between hyperbolic equation parameters and stack height is analyzed, and the inverse analysis method is used to obtain the foundation settlement coefficient and correct the settlement after work so as to confirm the reasonable unloading time of artificial filled soil foundation under surcharge preloading.Analysis results show that when the hyperbolic method is used for fitting the measured settlement data on the test section, the hyperbolic equation parameter β has a negative linear relationship with stack height.The unloading time after correction of post-construction settlement presents the tendency of power exponent reduction with the increase of overload ratio, and it no longer changes basically after overload ratio reaches 1.5(stack height is 9 m).At this time, the unloading time is 197d minimally, which meets specification requirements.