土工格室柔性挡墙极限主动土压力计算方法

Calculation method of active earth pressure under limit state for geocell flexible retaining wall

利用有限元法分析了土工格室柔性挡墙水平变位特征,得到了墙体中部水平变位的分界点,提出了主动土压力的计算方法。分界点上部位移模式接近平动,采用库仑主动土压力理论计算上部的土压力,分界点下部位移模式接近绕墙脚的转动,采用水平微分单元法计算下部的土压力,并比较了计算结果与实测结果。比较结果表明:土压力计算结果与实测结果沿墙高的分布形态及增长趋势基本一致,计算值比实测值略偏小一些,偏差最小为0.2 kPa,最大为2.9 kPa,平均偏小为1.2 kPa,可见土压力计算方法可靠。

The horizontal displacement of geocell flexible retaining wall was analyzed by finite element method, its cut-off point in the middle of the wall was got, and the calculation method of active earth pressure under limit state was put up. The displacement mode above the cut-off point was near translational and the earth pressure of the part was calculated by Coulomb＇s active earth pressure theory. The displacement under the point was near rotary around the foot of the wall and the earth pressure of the part was calculated by level differential element method. The calculation results were compared with the measured results. Comparison result shows that the distribution shapes and growth trends of earth pressures from the calculation and measurement are basically same along the wall, and the calculated results are a bit smaller than the measured ones. The minimum deviation between the calculation values and measured values is 0.2 kPa, the maximum one is 2.9 kPa, and the average one is 1.2 kPa. Obviously, the calculation method is reliable. 2 tabs, 7 figs, 14 refs.