Internal Force Calculation And Simulation Study On Combined Anti-slide Micro-piles

Since half a century, with engineering activities becoming increasingly frequent, the trendof landslide disaster increases year by year. So the study of the people of landslide occurrenceand movement mechanism and control measures of the unprecedented is active of all time,especially the development of engineering measures for preventing landslide is rapid. Theapplication of anti-slide pile is widely used among the Landslide prevention measures. Thegeneral anti-sliding pile causes the disturbance of rock and soil body and structure damage. Itaffects the construction quality and safety and the construction conditions are also limited easily,at the same time, the cost is also too high. In view of the many shortcomings of anti-slide pile, itis urgently necessary to research and apply new technology of anti-slide pile. As the technologyadvances in the field of machinery, materials, etc, prevention and control engineering measuresare developing in the direction of light-duty and miniaturization. Then micro-pile is fit for thetrend of development. Because it has advantages of strong adaptability to field, small slip massdisturbance and fast construction speed. It is mainly used in the landslide control project andhave achieved good results. But its theoretical research is still far behind the engineeringapplication, so it needs to be carried out the research quickly.The road from Xining to Jiuzhi(S101line) in Qinghai province is an important provincialhighway in the southern of Qinghai province, however, landslides and other geological diseasesfrequently occur, which results in the destruction and falling of the subgrade or even trafficdisruption. According to the engineering geological conditions of the regional landslide hazards,it provides a valuable opportunity for theoretical study and engineering application. Accordingto the geological characteristics of the landslide, this article takes the S101line of the K364-1#landslide as the research object. It raises combined anti-slide micro-piles combineing withprestressed anchor cables and comprehensive control measures for drainage project, and begins with the analysis of mechanism of micro-piles. The paper takes the theoretical analysis andcalculation, model test and numerical calculation as the main research method, focusing on thecalculation of internal force of micro-pile and its stress characteristics under the action ofhorizontal load. The main conclusions and achievements are as follows:1. Calculate the shear capacity of single micro-pile in two ways. The result of the landslideand micro-pile shows that the shear resistance of reinforced effect only considered is morereasonable.2. Using internal force calculation method of structural mechanics, the internal forcecalculation formula of each rod end of the plane rigid frame structure simplified by3×3tinycombined anti-slide micro-piles is deduced.3. Through the model test of horizontal load of the micro-pile, it draws a conclusion that:First, with the pile number of increased, the micro-pile top displacement of the combinationsystem of rigid frame of three piles and four piles is less than single pile and the strain of pilebody of rigid frame system is less than single pile in the same of load conditions. Second, themicro-pile of front-end loading pressure, embedded solid loading pulled, and contrary to theends of the pile. Third, after the rigid frame structure of single pile, three pile and four pile, itneeds a long period of the long plastic deformation stage before it reaches the destruction Itindicates that the micro-pile has a strong capacity of deformation adaptation and coordination.In terms of anti-sliding effects, the rigid frame system is superior to the micro-piles ofsingle-pile structure.4. By using FLAC3D to analyze the effect of combined anti-slide micro-piles in K364landslide control, the numerical results show that horizontal displacement and verticaldisplacement of landslide is reduced after combined anti-slide micro-piles join in the slope toe.The whole slope is in steadily state, which shows combined anti-slide micro-piles againstsliding ability significantly.Through the above research results and conclusions, it has reference value to theoreticalstudy of micro-pile and similar landslide treatment engineering.