Zhengzhou Silt Arch Between Anti-slide Piles And Reasonable Pile Spacing

With the continuous expansion of urban construction scale,the difficulty of urban slope management has been escalating.Anti-slide piles are increasingly used in slope control because of their excellent anti-skid performance.In the design of anti-slide pile,the value of pile spacing is very important.The value of reasonable pile spacing lies in the formation of pile-soil arch,and the landslide thrust is transmitted to the load-bearing pile.Anti-skid property of pile.Because of the direct correlation between pile spacing and soil parameters,there are great regional differences.In many areas,because of the lack of systematic research results,the distance between the piles is too conservative and can not take into account the safety and economy of the project.The results show that there is no pertinent study on the soil arch and the spacing between the soils in the silty area,and most of them are silty in Henan Province.The formation rule of the soil arch between the pile and the reasonable pile The spacing value is very necessary.In this paper,the formation rule of soil arch between anti-skid piles is studied in three aspects.Taking the silt of Zhengzhou Yellow River Highway as an example,the indoor model experiment is carried out.According to the experimental phenomena and the measured data,The arching rule of the soil arch and the ratio of the spacing between the pile and the pile in the silt are calculated.The discrete element method is used to simulate the PFC two-dimensional,and the results of the indoor test are analyzed and validated.The reasonable spacing and arching According to the numerical simulation results,the soil arching model of the silt is selected.Based on the previous theoretical research,the deduction formula of the pile spacing is modified.Through the comparison of the engineering examples,the most suitable soil Arch model and pile spacing derivation formula.The main contents include four aspects.1.Select the silt in the middle section of the Zhengzhou Yellow River Highway Bridge,and establish a narrow proportion of the indoor anti-slide pile and pile model,and carry out different pile spacing(2 times the pile width,3 times the pile width,4 times the pile width,5 times the pile width)and(0.6KPa,0.9KPa,1.2KPa,1.5KPa,1.8KPa).The effects of different levels of landslide thrust and pile spacing on the formation and failure of soil arch are studied.The influence of pile spacing and landslide thrust on the formation and failure of soil arch are obtained,and thereasonable pile spacing in the silt is obtained.The influence of pile spacing and landslide on the formation and failure of soil arch is obtained.The ratio of pile to pile width,and the reasonable pile spacing under the conditions of soil arch bearing capacity and the remaining group ratio.2.The numerical simulation is based on the experimental size.The PFC discretization method is used to simulate the pile and soil plane.By using the advantages of the software itself,the soil arch is observed and calibrated by the formation and destruction of the soil arch during the loading process The distribution of soil particles in the process of formation and failure,the stress distribution of the soil between the piles,the trend of soil movement and the displacement range of the soil.According to the numerical simulation results,the formation and failure of the soil arch are obtained.The numerical simulation results are compared with the experimental results to determine the range of reasonable pile spacing in the silt,the bearing capacity of the soil between the piles and the ratio of pile displacement and pile width during the formation of the soil arch The results show that the soil arching model is the direct type.3.The influence of the parameters of the silty soil on the expression of the arch axis is studied by using the parameters of the silty soil to redefine the parabolic arch axis,and the ratio of the arch to the arch is obtained under the condition of reasonable pile spacing.Based on the previous study of soil arch and pile spacing between the piles,the stress model of soil piles is modified.Based on the modified formula,the most unfavorable force of the anti-Point for the anti-slide pile cantilever root.4.By comparing the existing parameters of the actual engineering,according to the two kinds of classical soil arching model modified by this paper,the results of the comparison of the engineering parameters are substituted respectively.It is confirmed that the results of the direct soil arch model selected in this paper are closer to the actual project.And the comparison between the indoor model test,the numerical simulation and the reasonable pile spacing determined in the theoretical derivation are proved to be applicable in the silty area of Zhengzhou.