Experimental study on static and dynamic performances of modular reinforced earth retaining wall

Reinforced earth retaining walls, as part of the roadbed, are not only subjected to static loads such as road infrastructure, but also subjected to traffic loads caused by vehicle movements. To investigate the mechanical properties and working performance of modular reinforced earth retaining walls under static and dynamic loads, the large-scale laboratory model tests were conducted, in which the variation laws of the mechanical behaviors such as the settlement of reinforced earth retaining walls, horizontal displacement of panels, lateral earth pressure coefficient and geogrid strain were compared and analyzed. The results showed that the damage modes of retaining walls under static and dynamic loads are local shear damage and panel extrusion damage, respectively, and the maximum strains of the geogrid are 1.7% and 4.5%, respectively, neither of which reaches the damage strain. The ultimate bearing capacities of the retaining wall under both static and dynamic loads are identical, and the maximum settlement of the top of the wall under dynamic load is increased by 280% and the horizontal displacement of the panel is increased by 180% compared with those under the static load. The deformation of the surrounding soil by extrusion during the descent of the load plate imposes horizontal additional stress on the panel, resulting in a larger lateral additional stress coefficient Kr than the theoretical value at the back of the wall. Under the action of dynamic load, the soil particles move irregularly, and the peak acceleration in the soil increases with the increase in load amplitude and decreases gradually from top to bottom along the height of retaining wall. The research results are important in revealing the mechanical behavior and damage mechanisms of reinforced earth retaining walls under static and traffic loads and in improving the relevance of model tests to actual engineering.