Centrifugal Test And Analysis Of Cantilever Retaining Structure

With the trend of heavy load and high-speed railway, railway line has been given a large radius curves and straight lines. Using retaining structure has become an inevitable process of railway building for the conservation of land resources. Cantilevered retaining wall are widely used because of small thickness, light weight and good economic indicators.The safety of the cantilever retaining wall design largely depends on the analysis of the calculation of earth pressure. The Coulomb method now used in the calculation of earth pressure adopted many assumptions, what’s more many built structure didn’t get the active limit state. So this kind of method is just ok for the design of the common railway but as the railway is becoming speedier and more heavy, the theory of calculating earth pressure should be researched in-depth.Only through that we could make the earth pressure and the displacement of the coping clear and make the retaining structure safer and economic.This paper is part of the research on Railway subgrade Retaining structure limit state method by Ministry of Railways. The research of cantilever retaining wall which is widely used in retaining walls of railway based on the centrifugal model test of different loads and different wall heights.This research reveals the value of the earth pressure、earth pressure distribution and the displacement of the wall.(1)Comparing the metrical value with the numerical value, we get the earth pressure distribution under the condition of smooth heel wall board. Cantilever retaining wall earth pressure measured values are greater than the theoretical value. The ratio of the measured value and the calculating value under Rankine earth pressure method is recommended of 1.25. The ratio of the measured value and the calculating value under Coulomb calculation method is recommended of 1.32 to 1.39.(2)By ANSYS (numerical analysis software),getting the trend of wall back earth pressure is substantially the same, approximately triangular distribution under the conditions of different wall height and loading. Then the 6m high retaining wall pressure at the upper-line load of 60.2kPa, is 1.6 times than the pressure of soil weight condition, and it is 1.92 times when the upper load is double load.(3)By theory, numerical calculation, experiment three test comparison of cantilevered retaining wall top displacement,the method of theoretical calculation of displacement is greater than the measured results and the current theory is somewhat safe computing. With the retaining wall height increasing, the calculated results with measured results ratio decreased from 1.5 times to about 3 times. It shows retaining wall with height real increasing, the top displacement is nonlinear substantial increases. We can conclude that after the retaining wall reaching a certain value (in this table is 7.5m), its displacement will have a substantial increase trend.