高速铁路对路基工后沉降提出了严格的要求,某高速铁路路基段存在大范围软土地基,采用水泥砂浆桩进行地基加固处理。通过对地基处理后一年多的路基沉降变形观测分析及预测表明:各观测点的沉降量-时间曲线均已经收敛,路堤荷载作用下路基面沉降已经稳定,沉降板预测最大工后沉降ΔS’为4.8mm,路基面观测桩双曲线法预测路基面最大残余沉降为2.3mm,沉降完成比例St/S∞最小为92.4%,均满足高速铁路沉降控制标准。因此,水泥砂浆桩处理高速铁路软土地基是可行的,可以在较短时间内满足工后沉降的要求。
High-speed railway puts forward strict demands on post construction settlement. There is a wide range of soft ground at one high-speed railway embankment, which is strengthened by cement mortar pile. Based on a- nalysis and prediction of settlement after one and a half years monitoring, we have found that settlement-time curves of every observation points are convergent and settlement of embankment surface under embankment load is stable. The predicted maximum post construction settlement (AS') of settlement plate is 4.8mm and the maxi- mum residual settlement of observation pile predicted by hyperbolic method is 2.3ram, the minimum completion percentage ( S/S~ ) of settlement is 92.4%, all of which can meet the settlement control standard of high-speed railway. So it is feasible to reinforce the soft foundation of high-speed railway with cement mortar pile because it can meet the requirements of the settlement in a relatively short period of time.