整体面板式土工格栅加筋土挡墙现场试验研究

RESEARCH ON GEOGRIDS REINFORCED SOIL RETAINING WALL WITH CONCRETE RIGID FACE BY FIELD TEST

以赣(州)龙(岩)铁路整体现浇面板土工格栅加筋土高挡墙为工程依托进行现场原型试验。通过现场埋设土压力盒、柔性位移计和水平测斜仪等测试仪器,进行包括加筋土墙体基底应力、墙背侧向土压力、拉筋变形和墙面水平变形等内容的测试。测试结果表明:加筋土挡墙基底垂直土压力沿土工格栅拉筋长度方向呈非线性分布,最大值发生在拉筋中部附近,向拉筋两端方向逐渐减少;实测墙背侧向土压力沿墙高呈非线性形式分布,其值小于主动土压力;上部墙体拉筋应变沿筋长呈单峰值分布,下部墙体拉筋应变沿筋长呈双峰值分布;上部墙体潜在破裂面形状与"0.3 H法"接近,而下部墙体潜在的破裂面形状与朗肯主动土压力结果接近;施工期墙面最大水平变形位置在挡墙的下部,竣工后墙面最大水平变形发生在墙顶处等。该结论为类似工程的研究与设计提供参考。

The field test of geogrids reinforced soil retaining wall with concrete rigid face is done in the Ganzhou-Longyan Railway main line of China. The test includes the measurement of the basement pressure and lateral pressure of the reinforced soil wall, the tensile force of the reinforcement and the lateral horizontal displacement of wall. The basement vertical pressure of the reinforced soil retaining wall is nonlinear along the reinforcement length; and the maximum value is in the middle of the reinforcement and reduces gradually to the two ends. The testing lateral pressure of the reinforced soil wall is nonlinear along the height and the value is less than the active lateral earth pressure. The tensile strain along reinforcement at the upper wall is a distribution of single peak, but the tensile strain along reinforcement at the lower wall is twin peak values. The potential fracture plane at upper wall is similar to 0.3 H method; but the potential fracture plane at lower wall is near to the active Rankine earth pressure theory. The maximum lateral displacement of the wall face during construction is at lower position of wall; and the maximum lateral displacement of the wall face after construction is at top of the wall. These test results can be used for references in future studies and designs of geogrids reinforced soil retaining walls.