The Numerical Simulation Study Of Micropile In Expansive Soil Slope

As a new retaining structures for the landslide, the Micropile is a type of small diameter bored pile of which the diameter is between100and300mm. Compared with the traditional retaining structure,This kind of small diameter pile is characterized with fast construction,safety and reliability,small perturbance, low cost, strong applicability, in view of the characteristics of the Micropile, the Micropile is very suitable for Reinforcementing expansive soil landslide that is medium and small bursty type on shallow layer.The Micropile is a new technology of treating landslide, Micropile theory research is in the initial stage, The design concept of the Micropile is not mature, people mainly use the traditional anti-slide pile design method, construction work refer to engineering experience,which seriously hampered the promotion and application of the Micropile.In this paper, the FLAC3D software is applied to simulate the Micropile in landslide treatment.lt is known that the effect of Micropile reinforcing landslide was very obvious by numerical analysis,compared with the traditional retaing structure, the Micropile belonged to flexible supporting. The pile group produce displacement because of the downslide force, the displacement of the pile top is maximum, the sliding surface stress is maximum,under the condition of reasonable design parameters, more than90%of the displacement of the sliding surface was decreased because of the Micropile. The plastic zone of the slip mass disappeared, which is effect of reinforcement slope. After simulation and comparison of multiple analysis, it is discovered that the effects of piles row distance is smaller for reinforcementing; we found that the slope will bring about grear displacement with pile spacing increases,it will Collapse in the end,ti is reasonable that piles space is5-10times of the pile diameter. The connection beam can improve the micro pile lateral stiffness. The study found the effective soil arching will be developed between piles,when the Micropile’s distance is5-9times the diameter of the piles. Expansive soil is strong cracks, porosity, water permeability, it is more easy to form shallow and local landslide under the action of water,which cause further sliding in the rear and lower soil.The research results of the Micropile provide a better theoretical material, and have a positive significance on the design and construction of the landslide treamment.