强夯置换处理沙漠湖区砾石土路基试验研究

Experimental Study on the Treatment of Gravel Subgrade in Desert Lake Area by Dynamic Compaction Replacement

为分析沙漠湖区水下砾石土路基过渡段采用强夯置换法对置换墩体及墩间土的加固效果,采用强夯置换法对砾石土水下路基进行处理,监测其夯沉量、地表隆起量及超静孔隙水压力,并采用动力触探试验等方法检测其加固效果,通过监测、检测数据分析砾石土水下路基置换墩体及墩间土的加固效果。研究表明:2500,3500kN·m^(2)种能量下强夯置换单点最佳夯击数为11~12击;夯击时墩体周围地面以下沉为主,地表隆起量小;路基超静孔隙水压力消散快,多遍点夯施工时可连续施工;强夯置换能量主要影响置换深度及墩体密实度,对墩间土的加固效应影响小;强夯置换过程对无黏性的墩间土有密实作用。

In order to analyze the consolidation effect of the underwater gravel subgrade in the transition section of desert lake area by dynamic compaction displacement method on the piers and soil between piers,underwater subgrade was carried out by dynamic compaction replacement,and settlement,surface uplift,excess pore water pressure and dynamic penetration test of that were monitored during dynamic compaction replacement.Based on the test data,the consolidation effect of replacement piers and soil between piers were analyzed.The results show that:The best ramming numbers for 2500kN·m and 3500kN·m are 11~12.The surrounding ground is mainly settlement,and the surface uplift is small.The excess pore water pressure dissipates quickly and can be constructed continuously during the construction of multiple times compaction.The ramming energy mainly affects the displacement depth and the compactness of piers,but has little effect on the consolidation effect of soil between piers.The dynamic consolidation displacement has the effect of compacting the non⁃cohesive soil between piers.