Research On Pile-soil Interaction Mechanism Of Double-row Anti-slide Pile Based On Transparent Soil Test

China is a mountainous country with frequent geological disasters.Landslide is one of the most common geological disasters.Double row anti slide piles are widely used in large and medium-sized landslides because of their advantages of flexible arrangement and good anti slide effect.However,the mechanism of pile-soil interaction of double row anti slide piles is complex and its development starts late,so there are still many problems to be solved at present,especially the influence of pile spacing,row spacing and layout of double row anti slide piles on the mechanism of pile-soil interaction of double row anti slide piles influence.In this paper,based on the gradually mature transparent soil test technology in recent years,the indoor model test of double row anti slide piles is carried out,using the advantages of transparent soil for intuitive observation of the internal displacement field of the soil,at the same time,the numerical simulation method and the indoor test results are mutually verified,and further study the distribution of soil stress field when the double row anti slide piles play a role.The main work and research results are as follows:(1)Based on the transparent soil test technology,the transparent soil model test system of double row anti slide piles is designed.The guide rail is used to convert the vertical stacking load into the inclined landslide thrust along the landslide direction,and the loading parts are connected with the rotary lifting platform.It is not only convenient to calculate the corresponding relationship between the stacking load and the landslide thrust,but also conducive to quantitatively control the loading size and limit the loading speed,so as to ensure the accuracy of the test results.(2)In order to study the development rule of the horizontal soil arch distribution in the back row during the process of grading loading,the plum blossom double row anti slide piles with pile spacing of 4 times of pile diameter and 7 times of pile diameter were used to carry out the transparent soil model test.The test results show that the development trend of the horizontal soil arch position between the piles is gradually expanding from near the anti slide piles to behind the piles.Using ABAQUS to establish the finite element model consistent with the test size,through the numerical simulation results,it is found that in the process of load increase,the arch height of the stress arch between the rear piles increases continuously,and the test results are similar to the numerical simulation results.(3)In order to study the influence of row spacing on the mechanism of pile-soil interaction,the double row anti slide piles with 4 times of pile spacing and 3 times of pile diameter,5 times of pile diameter and 7 times of pile diameter were tested and simulated.The results show that the larger the row spacing is,the larger the displacement of soil near the anti slide pile is.The numerical simulation results are consistent with the test results.At the same time,the table also shows the numerical simulation results With the increase of the distance between the open rows,the displacement of the top of the slope decreases,while the rear pile thrust increases,and the front pile thrust decreases.(4)In order to study the influence of pile spacing on the mechanism of pile-soil interaction,the double row anti slide piles with row spacing of 5 times of pile diameter,pile spacing of 3 times of pile diameter,4 times of pile diameter and 5 times of pile diameter are tested.The results show that the larger the pile spacing is,the larger the displacement of soil near the anti slide pile is.The numerical simulation results are consistent with the test.The numerical simulation results also show that after the pile spacing is increased,the rear row will be replaced The soil arch area behind the pile extends backward.However,there is no obvious change in the area of pile soil arch in the front row.