基于土工格栅加筋优化技术的高速公路路基加宽技术研究

针对旧路基加宽易导致路基发生差异性沉降而形成裂缝的问题,采用土工格栅加筋来提高路基的稳定性。通过建立加宽路基的有限元模型,获得不同土工格栅加筋对加宽路基的性能提升。结果表明:未加铺土工格栅时,原路基地表沉降曲线呈勺形,最大沉降出现在路肩处;地表水平位移曲线呈S型,以路基中心13 m为界,左侧水平位移指向内侧,最大位移为18 mm,右侧水平位移指向外侧,最大位移28.10 mm。对比不同加铺土工格栅方案对加宽路基性能的优化可以看出,铺设土工格栅来减少路基沉降效果和降低地基中应力获得的效果并不明显,但能够较好地减少路基的水平位移量。从经济角度考虑,采用第1/4/5组合,即下部铺设两层,顶部一层加铺土工格栅具有较好的效果。

Research on Subgrade Widening Technology of Expressway Based on Geogrid Reinforcement Optimization Technology

in order to solve the problem that the widening of the old subgrade is easy to lead to the differential settlement of the subgrade and the cracks are formed,the geogrid reinforcement is used to improve the stability of the subgrade.In this paper,the finite element model of widening subgrade is established,and the effect of different geogrid reinforcement on the performance of widened subgrade is obtained.The results show that when the geogrid is not added,the surface settlement curve of the original subgrade is spoon-shaped and the maximum settlement occurs at the shoulder of the road,and the horizontal displacement curve of the surface is S-shaped,which is bounded by 13m in the center of the roadbed,the left horizontal displacement points to the inside,the maximum displacement is 18mm,the right horizontal displacement points to the outside,and the maximum displacement is 28.10mm.Compare different additions The optimization of widening subgrade performance by geogrid scheme shows that the effect of laying geogrid to reduce subgrade settlement and stress in foundation is not obvious,but it can reduce the horizontal displacement of subgrade.From the economic point of view,the first/4×5 combination,that is,the lower layer is laid with two layers,and the top layer is covered with geogrid has a good effect.