中文摘要：

为了研究返包式土工格栅加筋土挡墙在墙顶荷载作用下的受力和变形状态，分析其作用机制，通过室内模型试验，进行包括加筋土墙体垂直和水平土压力、应力扩散角、侧土压力系数、墙面水平变形和竖向沉降及土工格栅拉伸应变等分布规律的研究。试验结果表明：加筋土挡墙内垂直土压力沿筋材长度方向呈非线性分布，最大值位置从加载前位于筋材中部附近逐渐移动到加载点下；靠近墙面位置侧土压力沿墙高逐渐从加载前与自重应力线性相关变化为加载后从高到低逐渐减小的分布规律，其值小于主动土压力；实测应力扩散角较非加筋土体大，稳定的应力扩散角约为50＆#176;；侧土压力系数与荷载大小成正比，其沿墙高分布规律与水平土压力相似；墙面累积水平位移沿墙高呈“S”形曲线分布，最大值位于中下部；筋材应变沿其长度方向呈单峰值和双峰值的分布，峰值出现位置距墙脚的水平距离从高到低逐渐减小。

英文摘要：

Large-scale model tests in laboratory were carried out to study the behaviors of geogrids reinforced retaining wall of wrapped face under the loading on top of the retaining wall. The vertical and horizontal soil pressures,the stress diffusion angle,the coefficient of lateral soil pressure,the lateral displacement and the vertical settlement of wall face and the tension strain of geogrids were measured. The distribution of the vertical soil pressure along the geogrid length was found to be nonlinear and the position of the maximum pressure was moved from the middle of geogrids to the position under the loading point. The distribution of the lateral soil pressure along the wall height near the wall face increased linearly along the wall depth due to gravitational stress before loading and decreased along the wall depth after the overhead loading. The values of the lateral soil pressure were always smaller than the active earth pressure. The measured stress diffusion angle was greater than that of soil mass without geogrids and the stable values of the stress diffusion angle was 50＆#176;. The coefficient of lateral soil pressure was in direct proportion to the overhead loading,and its distribution along the wall height was similar to that of horizontal soil pressure. The cumulative lateral displacement of wall face had a distribution curve of S-shape,and its maximum value was located in the lower middle. The strain distributions of geogrids along its length were the curves of single-peak or twin-peak and the horizontal distance from the position of peak strains to the wall foot decreased gradually along the wall height.