The Research On Vacuum And Embankment Preloading Method Applied To The Treatment Of Soft Soil Foundation

Along with the rapid developments of expressway construction in China, the study on reasonable and reliable method of soft ground treatment has become a very urgent research subject in the geographical distribution of soft soil highway construction. In all kinds of soft ground treatment methods, vacuum and embankment preloading is a practical, economic, stable, wide adaptable and effective method in the treatment of large area soft foundation. It has broad application prospects dealing with soft soil in the highway construction. In this paper, the reinforcement mechanism and construction technology of the vacuum and embankment preloading method are analyzed.Firstly, the status of China's highway construction is summarized and its current problems have been pointed out in this article. A variety of soft ground treated methods were introduced. The history and research status of vacuum and embankment preloading method is been presented respectively from the aspects of theoretical and experimental research and construction technology research.Secondly, the status of reinforcement mechanism research of vacuum and embankment preloading is summarized. Separately the stress distribution and distortion development of vacuum preloading and embankment preloading are analyzed and the union reinforcement mechanism of vacuum and embankment preloading method is presented. Based on the former study, the vacuum and embankment preloading technology is analyzed and its improvement direction is proposed. Then a flexible membrane and rigid membrane under compression test is been operated. The reinforcement mechnanism and soil deformation law of vacuum and embankment preloading are analyzed. Then according to compared analysis of all kinds of soft foundation treatments in a concrete project example, the characteristics and advantages of vacuum and embankment preloading is summarized. Meanwhile, based on the three-dimensional sand drain consolidation of the vacuum and embankement preloading and partially penetrated sand wells consolidation, the calculation formula for the settlement prediction of treated soft ground which can be used to guide the actual construction is obtained with the use of the inversion coefficient of consolidation. With the use of the grey system theory, another method for the settlement prediction of treated soft ground based on the Verhulst model is proposed. The accuracy and rationality of all the methods for settlement prediction are proved in some project example.Finally, the stability characteristics of soft foundation treated by vacuum and embankment preloading are analyzed. The stability model with circular arc force is developed. The reinforced effect of soft soil is tested in some actual project and some reliable datas and engineering experience could be provided for relevant design and construction in some similar projects.