路基渗流特性现场监测与数值模拟对比研究

Comparative Study on Field Monitoring and Numerical Simulation of Seepage Characteristics of Soil Subgrade

为了研究路基渗流特性,在广州市北二环高速公路K26＋280附近填方路基不同深度处,埋设TDR水分传感器,监测降雨条件变化对路基含水率变化产生的影响。监测结果表明,雨水入渗致使路基含水率改变的重要因素,雨季来临前含水率变化值在1%,雨季中其变化值最大达到12%;在雨季,路基顶部一定范围内出现暂态饱和区域,路面结构具有一定的防水性;强降雨阶段,在沥青路面下160-200 cm深度范围内路基含水率值较大,其余区域相对较小。通过与实测数据对比发现,三维有限元数值计算结果与实测结果有较大的相关性,为日后进一步的渗流规律研究提供了有力的工具。

In order to study the seepage characteristics of the roadbed,TDR was embedded in the North Second Ring Expressway of Guangzhou near K26 ＋ 280 subgrade at different depths and monitor effects of changes in rainfall conditions on the moisture content of Subgrade. Monitoring results show that rain infiltration is an important factor which causes the change of moisture content of subgrade. The change of moisture content before rainy season is1%,and the change of moisture content in rainy season is 12%. At the stage of heavy rainfall,the moisture content of subgrade is larger in the 160 - 200 cm depth range of asphalt pavement,however the rest area is relatively small. By comparing with the measured data,it is found that there is a great correlation between the numerical results and the measured results,which provides a powerful tool for the study of the seepage law in the future.