基于模型试验和数值模拟的土工格室加固高填路堤稳定性：以新疆G216线民丰段为例

为研究土工格室加固高填路堤的稳定性,通过开展室内模型试验,分析了在持续荷载作用下素土边坡和土工格室加固高填路堤边坡的沉降量和最大水平位移；基于室内模型试验,建立有限元模型,分析了不同加固条件下的坡顶沉降量、最大水平位移及土工格室应变,研究了土工格室高度、铺设间距以及不同铺设部位对高填路堤稳定性的影响。结果表明:铺设土工格室能降低边坡土体的沉降量和最大水平位移,进而提高边坡的承载力；素土边坡剪应变自坡顶至坡脚形成贯通的滑移带,铺设土工格室后,滑移带的位置由边坡表层深入坡体内部,且滑移带未完全贯通；增加土工格室的高度,边坡的沉降量和最大水平位移先减小后趋于稳定,安全系数先增大后逐渐平缓；边坡的沉降量、最大水平位移随土工格室铺设间距的增大而增大；减小土工格室铺设间距0.6~0.7倍,最大水平位移降低1.5~2倍,坡顶沉降量减小1.5~1.8倍,安全系数增大1.1~1.3倍。高填土路堤的侧向位移主要发生在边坡底部H/3处,在边坡底部H/3处减小土工格室的铺设间距、增加土工格室的高度能更好约束侧向位移和沉降量,是提高路堤稳定性更为经济合理的加筋方案。

Study on Stability of Geocell Reinforced High Fill Embankment Based on Model Test and Numerical Simulation

To study the stability of geocell reinforced high fill embankment, the settlement and maximum horizontal displacement of plain soil slope and geocell reinforced high fill embankment slope under continuous load were analyzed through laboratory model tests; Based on the indoor model test, a finite element model was established to analyze the settlement amount, maximum horizontal displacement and geocell strain under different reinforcement conditions. The influence of geocell height, laying distance and laying position on the stability of high filled embankment was studied. The result shows that the soil settlement and maximum horizontal displacement of slope can be reduced by laying geocell, and the bearing capacity of slope can be increased. The shear strain of the plain soil slope formed a through slip zone from the top to the foot of the slope. After the geocells were laid, the slip zone penetrated from the surface of the slope into the interior of the slope, and the slip zone was not completely through. With the increase of geocell height, the slope settlement and maximum horizontal displacement first decrease and then become stable, and the safety factor first increases and then gradually flattens. The settlement amount and the maximum horizontal displacement of the slope increase with the increase of the spacing of geocells. The maximum horizontal displacement is reduced by 1.5~2 times, the settlement of slope top is reduced by 1.5~1.8 times, and the safety factor is increased by 1.1~1.3 times. The lateral displacement of high fill embankment mainly occurs at the bottom H/3 of slope. Reducing the spacing of geocell and increasing the height of geocell at the bottom H/3 of slope can better constrain the lateral.