Response Analysis Of The Foundation Pit Support Structure Under Moving Load

In recent years, with the rapid development of economy, the number of vehicles was increasing and the phenomenon of overloading taken place frequently, urban road traffic was also increasing. At the same time, the influence of the vehicles load moving close to foundation pit on its support structure would become more and more serious. However, in the previous design of foundation pit support, the effect of vehicle load was rarely considered or as an equivalent static load. Therefore, the study of the moving load response of the foundation pit support structure has very important theoretical significance and practical value.The paper bases on WoErde central project in Wuhan. Consequently, by the half-sine wave load as moving load, the paper investigates the moving load response of the foundation pit support structure with ANSYS numerical analysis, and come to several conclusions as follows.(1) The anchors axial stress is increased to different extent under the moving load. Compared with the second anchor, the first anchor responses more obviously and its amplitude is greater. Under the moving load of different speeds, smaller the velocity, more adequate response and more obvious changes, and vice versa.(2) The top of the pile's lateral displacement and vertical displacement in the moving load changes in volatility. When the speed is 1 m/s, the average lateral displacement is 0.196 mm, the average vertical displacement is 2.91 mm, The 8m/s is 0.154 mm and 2.76 mm, Also, the 20 m/s is 0.085 mm and 2.53 mm. Under the moving load of different speeds, faster the moving load, its impact on the lateral displacement and vertical displacement of the supporting pile will be less and less, but too fast, the response may be a mutation and has the possibility of response distortion. The effect of moving load on the vertical displacement is significantly larger than the lateral displacement.(3) Under the moving load, the displacements of the different positions of the piles fluctuate consistently. From the top of the pile to its tip, lateral displacement and vertical displacement become smaller and smaller, also the amplitude of fluctuation. (4) The displacements of the surrounding solum in the moving loads have the similar fluctuation curves. The closer the solum to the vehicle load, the greater its volatility, the lateral displacement and vertical displacement is greater too. Under the moving load, the surrounding solum's lateral displacement is smaller than that of the supporting pile, but the vertical displacement is bigger.