Analysis On The Reinforcement Effect Of Lime-soil Compaction Pile On Loess High-fill Embankment

With the rapid development of China's economic construction, the highway in Loess Plateau region increased dramatically. Because of Loess Plateau's complex topography and highways'linear constraints, high fill and deep cut are conventional designs for the highway construction in this region. Settlement cracks caused by the settlement after construction and uneven settlement of high- fill embankment are the problems to be solved urgently. So it is particularly important that taking which kind of cost-effective engineering and technical means to treat loess high-fill embankment which can reduce the settlement after construction and settlement difference of high fill subgrade. Lime-soil compaction pile has a good treatment result for the building foundation in loess region and both of the treatment experience and theory are more mature, but the studies on the application and treatment result of the lime-soil compaction pile are less for the non-saturated loess embankment after rolling treatment. So it has a great significance to study the reinforcement result and settlement after construction of loess high-fill embankment which is treated by lime-soil compaction pile.Relying on the lime-soil compaction pile reinforcement project of Wubu-Zizhou highway high-fill embankment, analysis and research on the treatment result of lime-soil compaction pile are conducted by means of settlement calculation, numerical simulation and settlement monitoring. The main contents are as follows:Firstly, this thesis surveys the status after construction of Wubu-Zizhou highway high-fill embankment and analyses the early disease-prone multi-site, which, provide certain reference function for the construction and reinforcement of corresponding parts.Secondly, through the settlement calculation and numerical simulation before and after lime-soil compaction pile reinforcement of 20 meters high typical high-fill embankment, settlement changes before and after reinforcement under different compactness and compression amount change of soil before and after reinforcement under different compactness and loads are analysed. It concludes that loess high-fill embankment which has a compactness lower than 0.9 and height higher than 20 meters needs to be reinforced.Lastly, through the settlement observation of depth label and pavement label before and after reinforced by lime-soil compaction pile, it is discovered that silt basement is basically stable after treated by gravel pile, the settlement has been in a state of creep all the time and it just has a small settlement. The settlement of the embankment itself is the main part of the settlement after construction. The reinforcement with lime-soil compaction pile can reduce the settlement after construction largely and shorten the settlement period. It also has an obvious function on the rapid stability of loess high-fill embankment.