Large Scale Shaking Table Test Of Retaining Wall Backfilled With EPS Composite Soil

With the process of building large-scale infrastructure, there are often a large number of soil excavations, especially the construction of roads and bridges in mountain area, needing large-scale construction of retaining wall. In recent years, the earthquake disaster in China is becoming more and more frequent. The stability against seismic of retaining wall is a big challenge, while anti-seismic research on retaining wall is not enough, so that the study on the stability against seismic of retaining wall is urgent.Based on the feasibility study of EPS composite soil used in engineering, the project finish a series tests on the basic physical properties of EPS composite soil. Combined with the research status, Designed a set of large-scale shaking table test to study the seismic behavior of the retaining wall with EPS composite soil as backfill soil. The main work and conclusions are as follows:(1) Finished the test on basic physical properties of EPS composite soil, including density test, consolidation test, direct shear test. Results show that the density of EPS composite soil is mainly affected by the content of EPS particles, decreases with increasing EPS content. The shear strength increases with cement content, and the content of EPS particles was about 3% to get a relative maximum.(2) Designed a set of large-scale shaking table test on EPS composite soil, including the design of model structure and model foundation depend on test purpose; selecting the experimental device and layout of sensors; arranging and coordinate during the process of test.(3) Analyse the results of the shaking table test on the seismic energy dissipation of EPS composite soil as backfill behind retaining walls. The results show that, compared with the ordinary soil, the effect on seismic energy dissipation of EPS composite soil as backfill is obvious, can effectively reduce the peak acceleration of seismic wave; the earth pressure acting on the wall behind the apparent differs obviously; at the same position, strain of retaining wall with EPS composite soil as backfill is smaller, the peak acceleration is smaller, the wall displacement is smaller. Therefore, EPS composite soil as backfill can decrease the influence of earthquake load on the seismic stability of retaining wall.