海南海花岛软基处理工程中真空预压法的改进与机理分析

摘要

疏浚淤泥这种超软土地基目前主要采用排水固结法进行加固,然而,工程实践发现,淤堵是一个重要的问题,新型防淤堵材料和施工工艺是研究的热点.依托恒大海南海花岛真空预压处理工程,引入一种应用于超软土地基处理的新型防淤堵真空预压法.该方法是直排式真空预压方法的进一步改进,将防淤堵排水板取代传统排水板,在连接方式上,将无孔钢丝软管取代了水平波纹管,也将传统的包扎捆绑改进成了三通密封接头,枪钉固定.结合施工动态监测和加固后检测,表明了该方法的加固效果和实用性.在此基础上,结合已有的室内模型试验研究,阐述其抽真空过程中在排水板附近防淤堵的原理和改善机制.%At present,despite that the super soft soil foundation of the dredging silt is mainly strengthened by the vacuum-PVD consolidation method,the clogging is an important issue during the field application.With the vacuum preloading project of the Hengda Sea Flower Island in Hainan Province,a new type of anti-clogging vacuum preloading method for the super soft soil foundation is developed.It is the further improvement of the straight-line vacuum preloading method.The traditional PVD is replaced by the anti-clogging PVD,and the nonporous steel hose and tee sealing joint are also applied to update the traditional connections.Thereafter,the in-situ monitoring during vacuum and quality evaluation after construction is detailed introduced.The results verify the effectiveness and applicability of the preloading vacuum method'amendment.Combined with the existed laboratory model test,the principle of clogging in the vicinity of the PVD during vacuum preloading,and the mechanism of improved vacuum preloading are also discussed.