以湖南益阳市水网湖区综合管廊工程为例,结合益阳典型软土地质条件对基底沉降进行分析。基于现场资料,采用有限差分软件FLAC3D进行综合管廊及场地土体的数值模拟,将数值模拟所得的路基基底沉降值与现场实测值加以比较。在这一基础上,采用数值模拟方法分析在路堤荷载及车辆荷载作用下,综合管廊埋深、沟底碎石垫层及沟背回填土密实度这3个因素对路堤基底沉降的影响。分析结果表明:数值模拟与现场实测所得的埋深2m工况下路基基底沉降曲线吻合较好,证明该数值模型具有一定的合理性;路基基底沉降呈“W”形,且随着路堤填筑高度的增加,路基沉降更加显著。 Taking the Integrated Pipeline Project of Shuijingu Lake District in Yiyang City, Hunan Province as an example, the subsidence of the foundation is analyzed based on the geological conditions of typical soft soil in Yiyang. Based on the field data, the finite difference software FLAC3D was used to carry out the numerical simulation of the integrated pipe gallery and the site soil. The subsidence value of the subgrade obtained by numerical simulation was compared with the actual measured value. On this basis, the influence of embankment load and vehicle load on the subsidence of embankment base on three factors including embankment embankment depth, gravel bottom of ditch and backfill density of ditch back is analyzed by numerical simulation method. The results show that the numerical simulation is in good agreement with the measured subsidence curves of subgrade under the depth of 2m under field conditions, which shows that the numerical model is reasonable. The subsidence of subgrade is “W” Filling height increases, the subgrade settlement more significant.