强夯垫层法对河谷区软土地基加固效果研究

Research on the Reinforcement Effect of Dynamic Compaction Cushion Method for Soft Soil Foundation in River Valley

软土地基因其承载力低、压缩性强、沉降量大、稳定性差等不利特点,常常给道路路基工程施工和运营造成很大危害。针对云南省某高速公路河谷区复杂沉积环境多层软土地基采用强夯垫层法处理的加固效果与沉降变形进行了研究,在地基处理及路基填筑期间,获得了不同观测断面布设的沉降管、土压力盒、孔隙水压力计等的监测数据,分析了不同类型软土地基土体的变形、应力和孔隙水压力等数据随时间的变化规律,揭示了强夯垫层法处理不同类型软土地基的加固效果、有效加固深度和范围,提出了强夯处理后静置期的合理时间及填筑速率等控制参数等。

Soft soil foundation often brings great hazards to the construction and operation of road subgrade due to its low bearing capacity, strong compressibility, large settlement, poor stability and other adverse characteristics. In this paper, the reinforcement effect and settlement deformation of multi-layer soft soil foundation treated by dynamic compaction cushion method in the valley area of an expressway in Yunnan Province are studied. During the foundation treatment and subgrade filling, the monitoring data of settlement pipe, earth pressure box, pore water pressure gauge etc. that arranged in different observation sections are obtained, and the variation laws of soil deformation, stress and pore water pressure of different types of soft soil foundations over time are analyzed, and the reinforcement effect, effective depth and range of the dynamic compaction cushion method to treat different types of soft soil foundations are revealed;and the control parameters such as the reasonable time of the resting period after the ramming treatment and the filling rate are put forward.