采用强夯置换墩加固湿地中高速公路路基的研究  

STUDY ON DYNAMIC COMPACTION REPLACEMENT FOR REINFORCING FREEWAY ROADBED IN WETLANDS

作　　者：董伟[1] 闫澍旺[1] 冯守中[1] 闫福生[2] 

机构地区：[1]天津大学建筑工程学院,天津300072 [2]河北大唐国际唐山热电有限责任公司,河北唐山063000

出　　处：《岩石力学与工程学报》2009年第A01期2966-2972,共7页Chinese Journal of Rock Mechanics and Engineering

摘　　要：海拉尔至满洲里一级公路部分路线穿越海拉尔河漫滩湿地,软土层位于地表,厚度较薄,而且地下水位较高。综合考虑施工难易以及经济效益,提出强夯置换墩复合地基的设计方案,采用在夯坑内回填块石、碎石等粗颗料材料,形成大直径置换墩(桩)作为复合地基的骨架。强夯置换法是一种经济、简单易行的地基处理方法,但目前仍没有成熟的设计计算方法,施工前必须进行试夯以确定其适用性及加固效果。为此,进行了有限元分析,研究相同置换率条件下,桩(墩)径对加固效果的影响,为桩(墩)径的选择提供参考依据。通过试验区的试夯试验,确定施工参数,验证强夯置换法用于这类湿地地基的合理性。The road from Hailaer to Manzhouli passes through the Hailaer wetlands, where a thin soft soil layer exists on the ground surface. Furthermore, the ground water level is so high that in rainy seasons it rises over the ground surface. The dynamic replacement method（DRM） is chosen to comprehensively consider the feasibility of construction and economic effects. According to the design, some large diameter piles are formed by filling the rammed holes with crushed stones which are acting as the skeleton of the composite foundation. Dynamic compaction replacement is an economical, simple and convenient method for soil improvement, but there is no mature method for design and calculation, so before construction, representative field is often chosen in which field experiments are done in order to confirm applicability and the effects of reinforcement. Firstly, the effect of pile diameter on reinforcement results under a certain replacement ratio is studied using the finite element method. Based on the calculation results of the FE method, the diameter of the pile can be chosen and applied to in-situ construction. Through experimental research of dynamic replacement in the typical field, construction parameters are confirmed, and the rationality of this method used to improve this kind of soil foundation is validated.

关 键 词：土力学 强夯置换墩法 湿地 高速公路 桩(墩)径 有限元法 

分 类 号：TU43[建筑科学—岩土工程]