粒料夯柱现场综合试验研究

Case Study of Highway Embankment over Soft Ground Treated with Stone Columns

介绍成都绕城高速公路粒料夯柱处理软土地基的载荷试验成果 ,粒料夯柱作为一种公路工程中增强软土地基承载力的方案 ,其柱长为 1 5～ 4m ,直径为 1 2m ,间距为 3m。荷载试验在夯柱顶上和柱间地基土面上进行 ,试验采用循环加卸载的方式进行竖向变形与荷载关系曲线的测定 ,沉降稳定标准在每小时 0 2mm以内。试验成果可用作类似工程项目粒料夯柱优化设计。对于有较大面积的浅层软土且附近有丰富天然碎石的内地工程 ,粒料夯柱被证明是一种有效而经济的软土地基处理手段。

This paper presents the results of load tests conducted on stone column improved soft ground as embankment support in the construction of Chengdu Bypass Expressway, a ring road linking National Highway 108 (Beijing to Kunming)and National Highway 318 (Shanghai to Tibet).As one of the design alternatives in the improvement of embankment support in the highway project, stone columns were designed to 1.5 to 4 meters in depth, 1.2m in diameter and arranged at a spacing of 3m. Load tests were performed on columns and ground soil between columns. Vertical settlement and corresponding load intensity were recorded in the loading and unloading cycles with 0.2mm per hour as the creep standard. Test results can be used in the design optimization of stone columns with similar engineering scenarios. Stone columns prove to be an effective and economical means in the treatment of soft ground in inland projects where the depth of soft residual layer is limited and natural stone gravel material is affordable.