卵石持力层桩端后压浆效果检测分析

Analysis of Effect Testing of Post Grouting of Pile End in Scree Bearing Stratum

该文介绍了杭州德胜快速路桩端持力层为卵石层的两根桩端后压浆钻孔灌注桩所进行的自平衡测试。结果表明后压浆对钻孔灌注桩的承载力提高具有显著效果。通过钻孔取芯试验,发现压浆后20d测试时,水泥浆与土形成的水泥土固结体几何形状不规则,还未达到稳定,因此随着水泥土强度逐步提高,桩身承载力会进一步增大。通过对比分析,论证了后压浆技术会带来很好的经济效益。

The article introduces the self-balance test for two cast-in-place piles of pile end post grouting in scree bearing stratum of Desheng Expressway in Hangzhou.The result makes clear that the post grouting has the obvious effect to enhance the bearing capacity of cast-in-place pile.Through the test of drilling to take core,it is to find that the geometry figure of cement and soil concretion formed by the cement grout and soil is abnormal and is still not stabilized when 20d test after grouting.Therefore,the bearing capacity of the pile will further increase with the successive enhancement of the cement soil strength.After the contrast and analysis,it is demonstrated that the post grouting technology will bring the good economical benefit.