桩端后压浆在涡河大桥桩基中的试验研究

Experimental research on base post-grouting in pile foundation construction of Guo River Bridge

基于亳州涡河大桥桩基工程,文章进行了皖北地区粉质黏土地质条件下灌注桩后注浆试验;分析讨论了压浆试验装置的布设、压浆工艺、载荷试验的方法及影响质量的关键因素;针对粉质黏土的特点采用三次循环压浆法压浆,运用荷载箱法测试原桩和后压浆桩极限承载力,采用理论方法计算桩基承载力,理论计算结果具有实际应用价值。试验表明,后压浆桩极限承载力提升了41.7%,桩基力学性能得到很好的改善。文中给出的控制影响后压浆桩基施工质量的技术措施可供类似工程参考。

Based on the pile foundation project of Guo River Bridge in Bozhou City, the test of post- grouting of bored pile in silty clay soil in northern areas of Anhui Province is carried out. The setout of grouting test equipment, grouting process, load test methods and key factors that influence the construction quality are discussed. In view of the character of silty clay soil, the three-time circulation grouting technology is used, the ultimate bearing capacity of the original pile and post-grouting piles is tested by load-box method, and the capacity of pile foundation is calculated by the theoretical method. The theoretical results have sighificance in application. The test shows that the ultimate bearing capac- ity of post-grouting piles increases by 41.7G and the mechanical property of pile foundation is im- proved. The given technical measures to control the construction quality of post-grouting pile founda- tion can be a reference to similar projects.