高速公路软土路基沉降规律监测及FLAC模拟

Monitoring and FLAC simulating on settlement laws of soft soil roadbed of highway

采用粉喷水泥搅拌桩法,试验研究了高速公路软土路基沉降的变形特性,对路基关键部位的竖向沉降进行了现场监测,得到了软土路基的变形的初步规律。现场试验表明,粉喷水泥搅拌桩法适宜于加固饱和软粘土地基,可用于增加软土路基的承载力,减少路基沉降量。基于软土粘塑性蠕变本构模型理论,应用FLAC-3D软件完成了浙江某高速公路路基的的蠕变沉降规律的计算机模拟。FLAC-3D计算得到的竖向沉降与实际监测结果基本一致。计算表明,粘塑性蠕变本构模型可以较好地模拟软土路基变形问题,可将该模型用于软土路基沉降计算及预测预报,为软土路基沉降控制提供重要的理论依据。

Using on site monitoring to cement deep mixing method pile to dispose soft soil roadbed, the settlement laws of roadbed are studied. The settlement of key portions is monitored, and the primary laws of soft soil roadbed are gained. The on site testing results show that cement deep mixing method pile is suitable for reinforcing the saturated soft clay roadbed in order to increase the bearing capacity and decrease the settlement of the soft clay roadbed. Based on visco-plasticity creep constitutive model, the settlement creep deformation law of a highway roadbed in Zhejiang Province is analyzed with FLAC. The calculated results with FLAC are generally consistent with the on site monitoring results. It is concluded that visco - plasticity creep constitutive model is fit to simulate and forecast the settlement of soft soil roadbed, and can present important theory reference to the settlement control of soft soil roadbed.