灰土挤密桩复合地基浸水载荷试验研究

Study on Load Test in Soaking Condition for Lime-soil Compaction Pile Composite Foundation

以宝兰客专兰州枢纽工程某一涵洞为背景,采用灰土挤密桩处理该湿陷性黄土地基,通过现场浸水与未浸水载荷试验,分析处理后地基的效果。试验研究结果表明:经灰土挤密桩处理后,既能有效消除黄土的湿陷性,又满足规范和设计要求的复合地基承载力和沉降;浸水后地基承载力差异较小,沉降变化明显;垂直渗透深度大于水平渗透范围。

Taking a culvert engineering at Lanzhou Hub of Baoji-Lanzhou PDL as the background,the collapsible loess foundation thereof was treated by lime-soil compaction piles and the treatment effect on the foundation was analyzed by on-site load tests in soaking and unsoaking conditions.The results of the test study show that lime-soil compaction pile treatment may not only eliminate the collapsibility of loess effectively,but also meet the requirements of bearing capacity and settlement of composite foundation defined in the codes and designs; after soaking,the little difference presents in the bearing capacity and significant variation in the settlement; the depth of vertical permeability is greater than the range of horizontal permeability.