Research On Stability Of Soil Slope And Anti-slide Pile Reinforcement Based On Flac^3d

Stability of soil slope has always been a typical geotechnical problem, to which many engineers widely pay attention because of its frequency, destructiveness and uncertainty of soil parameters. With the large number of China’s infrastructure construction, a variety of new reinforcement measures, retaining structures are used in different soil slope projects, but as a measure with the advantages of quick construction, flexible pile position, good anti-slide performance, small disturbance and geological check in construction, anti-slide pile gets the favor. However, the theory lags behind the engineering practice, and it has become a hot topic but also a difficult point in research that how to get a simple, rational, scientific evaluation on stability of soil slope reinforced with anti-slide pile. In view of this, based on the results of previous studies, we make a further explore in the stability factors and research methods of anti-slide pile by the Flac3d strength reduction finite difference method. In this paper, the main work and research results are as follows:(1) comparing with the traditional limit equilibrium method and limit analysis method, it proves that the Flac3d strength reduction finite difference method is feasible in analysing the stability of soil slope, at the same time, in view of Simple operation and the clear physical meaning of slope failure, it is suggested that the convergence in numerical calculation can be the main criterion and the entirely run-through criterion of shear zone is secondary one when using strength reduction method, and the maximum number of step n can be three to five times of the number of elastic compute in the initial balance.(2) Cohesion c, friction angle (p, slope angle, groundwater level have a great impact on the stability of soil slope, while the poisson’s ratio μ and elastic modulus E is not sensitive. Due to its complexity and High computational cost to build the real3-D model, it is suggested to calculate on the fake3-D model by spliting several sections or more simple geometry, then get the safety factor range and make a evaluation on the the stability of soil slope.(3) The stability of slope, the position of the slip surface, the deflection and the internal force of piles are deeply influenced by the position, diameter, spacing and length of piles, when the piles are located in the middle of the slope and the diameter of piles is larger, or the spacing is smaller, the stability is better while the force of piles is larger. Within a certain range, increasing the length of piles can improve the stability to a certain extent, but too long length will cause unnecessary waste.(4) For the anti-slide pile slope with potential slip surface, propose a simple method to evaluate the stability and rational spacing through the analysis of failure modes, the safety factor of slope after reinforced with piles is determined by min(FS1, FS2, FS3), and the rational spacing R is determined by the Rk and R1, certainly, resistance method can be also used for such slope, In short, the modeling process will be avoided by the use of these two methods.(5) Study on a high soil slope of road has shown:groundwater, the excavation at the toe of slope and the clay interlayer have a great impact on the stability of slope, and the potential slip surface will also become more complex; when the anti-slide piles are set, the clay interlayer will make the force of piles become larger, so we need to pay more attention to the presence of the weak interlayer in the design of pile.