The Application And Experiment Research Of Cement Deep Mixing Pile And Plastic Drainage Board Well To Improve Soft-soil Roadbed

Middle or deep soft-soil layers distributed widely in China southeast seaboard area, Shooing Delta area, Yangtze River Delta area. The soft soil has characteristics of high water content and low anti-shears strength and high compression coefficient and low penetrability and high sensitivity. In the above areas building expressway will unavoidably face soft-soil. How to correctly evaluate and deal with the soft-soil roadbed of these areas, to work out a correct solution to the two technical difficult problems of stabilization and subside, which is important to build expressway and normally use when expressway is built. Therefore, how to deal with soft-soil roadbed has become one key technical problem to build expressway in soft-soil area. This paper combining with the construction of Yanhuai expressway which has characteristics of bad Geology condition and shorter work period and high quantity request. According to these characteristics, this paper raises the method of adopting short cement deep mixing pile and long plastic drainage board well to improve soft-soil roadbed, which is used in the construction of Yanhuai expressway. The experiment research indicates: this method has many virtues. Firstly, this method can effectively improve the stability of the soft soil foundation, quicken the roadbed construction velocity, shorten the period of engineering construction. Secondly, this method can effectively control the subside within the scope of certain. Thirdly, this method can lower the costs of the project. In a word, this method is a good method to solve the soft-soil foundation problem.