公路改扩建路基差异沉降特性研究

Study on Differential Settlement Characteristics of Roadbed for Highway Reconstruction and Expansion

摘要:

为提高公路改扩建项目建设水平，分析了路基差异沉降量的计算理论和主要原因，利用ANSYS15.0绘制数值模型，得到新老路基间的不均匀沉降变形，并探讨加宽高度、填料重度的影响规律。研究结果表明，路基竖向位移和水平位移基本呈中间小两边大的 “凸”形变化趋势，其最大值分别位于土路肩的边缘和新老路基结合位置；随着加宽高度和填料重度增加，加宽路基和地基土各监测点的沉降变形和新老路基间差异沉降也随之变大，且路基加宽高度从2 m至12 m，新老路基不均匀沉降提高129.3%，填料重度每提高5 kN/m3，新老路基差异沉降平均增加79.4%。

Abstract:

In order to improve the construction level of highway reconstruction and extension projects, the calculation theory and main reasons of differential settlement of roadbed are analyzed. The ANSYS15.0 is used to draw the numerical model so as to obtain the differential settlements and deformations between the new and old roadbeds. And the influence rule of widening height and filler weight are discussed. The results show that the vertical displacement and horizontal displacement of roadbed basically present the "convex" variation trend small in the middle and large in both sides. Its maximum values are located at the edge of earth shoulder, and at the combination of new and old roadbeds respectively. With the increase of widening height and filler weight, the settlement and deformation of each monitoring point of widened roadbed and subgrade soil, and the differential settlement between the new and old roadbeds increase. And the widening height of roadbed is from 2 m to 12 m. The differential settlement of the new and old roadbeds increases by 129.3%. When the filler weight increases every by 5kN/m3, the different settlement between new and old roadbeds averagely increases by 79.4%.