Study On The Earth Pressure Against Rigid Retaining Wall Considering The Movement Of Pratical Project

The determination of the magnitude and distribution of earth pressure against rigid retaining wall is important in the design. Classical earth pressure theories such as Coulomb and Rankine earth pressure theory have been widely used because they are simple and can reflect the mechanical concepts clearly. But the classical theories also have their shortages: they assumed the backfill of translation wall arrive the limiting. Rankine's theory can't take the wall friction into consideration, and the Coulomb's theory has the probable failure wedge as a rigidity and thus the distribution of the earth pressure is linear. Which are seldom for the retaining structures in service, especially for the huge ones. this makes the measured earth pressures on retaining wall, which are mostly non-linear, have considerable differences with the classical ones. So, it's necessary to propose a method for evaluating earth pressure considering the mode and the magnitude of wall movement.The study objection of the thesis is the rigid retaining wall whose back is vertical and the wall subjects to move outward and away from the backfill in different modes. There are three different wall movement modes named Translation(T), Rotation about base(RB), and the combinational one: Rotation about base & Translation (RBT). The paper defined the translating state from the rest state to the active one as "the inter-mediate active state". Based on the model tests and numerical analyses that researchers ever did, the progressive mechanisms of the soil strength with different wall movement were analysesd. Under different modes, with the movement of retaining wall and the deformation of the backfill increased, the strength of the backfill improved. In this process, the backfill, before failure, is taken as elastic medium, so that the elastic theory can be used to determine the law between the soil pressure and the magnitude of the retaining wall movement: with the magnitude of the movement of the retaining wall increasing, the strengths of the backfill develope, leading the earth pressure reduces from rest pressure to active pressure. the modified Coulomb's solutions of active earth pressure were used to calculate the lateral earth pressures, which is one of the wedges in this theory. Comparisons of the calculated results with observations from model tests show that the proposed methods can provide good predictions of earth pressures for different wall movement modes.