Analysis On The High Fill Embankment Stability And Settlement For Mountain-side Soft Clay Foundation

With the rapid development of transportation construction in China, theconstruction of high-grade highway, especially in coastal areas has made a greatachievement in the past decades. As being situated on the coast with a hilly landform,numberless mountains and soft soil are spread all over the Fujian province, whichresults in the high fill subgrade is inevitable during the process of road engineeringconstruction. Even in some particular lots, some more complicated situations, themountain-side soft foundation of high fill embankment have to be resolved by usingsome empirical design techniques. However, due to the specialization of themountain-side soft foundation of high fill embankment, accompanied by soft groundand hard ground, and that muddy soil of the soft ground has extravert slope on thecross-section direction, which is adverse for the stability of the high fill slope and thefoundation settlement’s control. So the soft ground section is the key part of controlembankment slope stability, that’s local stability plays a leading role, it’s differentfrom ordinary high fill soft embankment.The thesis based on a subgrade engineering in Fujian, K0+960~K1+160is onesection of the project, which is the mountain-side soft foundation of high fillembankment, the largest fill high is17m. By finite element software GeoStudio,which combined with the limit equilibrium and finite element, to perform a dynamicanalysis on the mountain-side soft foundation of high fill embankment slope. Bycomparison the embankment slope stability and ground settlement under threedifferent forms: the ground without treatment, ground with treatment, and withretaining reinforcement structures. The results show that the method in the evaluationof the mountain-side soft foundation of high fill embankment slope stability iseffective, especially when the safety coefficient close to1.0，can be combined withthe finite element simulation of the strain deformation more accurately to determineembankment slope stability, which can provide a reference for the similar slopestability evaluation in future.Through the simulates changes of pre-stressed anchor and slide-resistant piles’ internal force,with measured data to predict and by finite element method to simulate the ground total settlement,differential settlement and post-construction settlement, the results show that the method in theevaluation of the mountain-side soft foundation of high fill embankment slope stability iseffective.