基于双曲线法的分级填筑路堤沉降预测

Settlement prediction of stage constructed embankment on soft ground based on the hyperbolic method

在软土地基上修筑路堤多采用分级施工的方法。基于传统双曲线沉降预测法基础上,提出一种软土地基上路堤分级施工情况下沉降预测的新模型,该模型考虑了土体变形的非线性特性和固结性质随荷载的变化,将沉降拟合方程中的待定参数在2个不同荷载级中分别确定。利用有较长预压期的前一级实测沉降,确定与土的固结性质有关的参数,待预测沉降荷载级的最终沉降量由该级较短预压期内实测沉降确定。通过工程实例验证了所建议模型的适用性。

Stage construction is a typical procedure for expressway embankments on soft ground. Based on the traditional hyperbolic method, a new model for prediction of settlement of stage constructed embankment on soft ground is presented. In the proposed model, soil deforms nonlinearly, and its consolidation properties vary with the magnitude of the load. The parameter a related to consolidation properties of soft soil is determined by the settlements measured at the forestage with longer preloading duration; the other parameter, the final settlement Sf, is determined by the settlements measured in shorter preloading duration at which stage settlements are to be predicted. A case study shows predicted settlements are fairly consistent with measured settlements. The proposed model is accurate and easy to operate, and can predict settlements in practical engineering in time.