Research On The Pile-soil Interaction Mechanism Based On Centrifuge Model Test

With the rapid development of China’s economy, Contradictions that people willbe more and area is fewer is outstanding. But our country land area nearly two-thirdsin the mountains, in the mountains for engineering activities inevitably meetlandslides and other geological disasters, the effective measures for prevention andcontrol of landslide is main using friction pile or composite structure, in the process ofthe anti-slide pile supporting landslide, the soil between piles under the someconditions will produce the soil arch effect, the effect of bearing capacity of soil canplay to strengthen the supporting effect of anti-slide pile. In order to verify thedistribution of soil arching effect and research pressure and change which back of pile,pile stress distribution and anti-slide pile distance and the biggest reasonableanchorage depth, using the chengdu university of technology of TLJ-500largegeotechnical centrifuge modeling of natural state and under the condition ofgroundwater of pile-soil interaction phenomenon, the main research results are asfollows:1.Under the natural conditions, different pile distance and the anchoring depthanti-slide piles pressure distributions were similar, showing obvious nonlinearcharacteristics.Through the test, and compared with previous theoretical andexperimental research showing that the natural conditions, the distribution of soilpressure between anti-slide pile and pile after form for approximate parabolicdistribution, and the research achievements can fit well to predecessors.2.Under the natural conditions, compared with previous theoretical andexperimental research showing that the bending moment distribution of anti-slide pileis approximating parabolic distribution, and the central of the pile’s stress is thelargest, the stress of the top pile and bottom is much smaller than central of pile, andthe damage of anti-slide pile are from the central of pile. It is show that the the centralof pile is the most easy to damage to the cantilever anti-slide pile; Under thegroundwater conditions, their mechanics characteristics change is relatively complex,with the development of the time, the overall performance of the forces exerted to thepile at the bottom of the pile,the stress is greater than the top and central of the pile; As anchoring depth of pile decrease, the degree of tension increases overall at thebottom and centre of the pile. At the top of the pile from pure tensile state transfer totensed and compressed alternation, and along with the further decrease of anchoragedepth, the compression degree at the top of pile increasing.3. With the increasing of pile distance, arch camber is much high, the soil archeffect is even not obvious. Under the groundwater conditions, damage of soil betweenpiles and arch camber height is greater than the soil between piles under the naturalcondition.4. According to the biggest pile distance calculation model put forward byscholar Wang qiankun, the calculation result is most consistent to the test, the biggestdistance between pile is7.2m, equivalent to the5d pile in the test; In terms of the testfor the effectiveness of the soil arch between piles distance range between4d~6d(dfor the pile width), namely range from6m to10m between pile.5. According to the engineering experience and the effect of centrifugal modeltest about piles and soil interaction, that when the anchoring section is completebedrock section, the anchoring depth of pile for a quarter of the total length isrelatively feasible and more economic.