Study On Earth Pressure Distribution Of Pressure-dispersive Retaining Wall And Ultimate Bearing Capacity Of Anchor-plate

As the infrastructure construction developed rapidly in our country, the shortage of land resource is more severe, thus retaining wall is widely used in infrastructural project for its excellent usability. Traditional cantilever retaining wall does not apply to high fill subgrade for it improves bearing capacity by increasing the thickness of wall. Anchor plate retaining wall has complex construction procedure and the overall strength at the bottom of the wall is low. Pressure-dispersed retaining wall combines the advantages of both cantilever retaining wall and anchor plate retaining wall, it provide lateral restraint by setting more than one anchor plate at the same height, which can not only improves the prestressing force of bolt, reduced the sectional area of wall body, but also improve the design height of retaining wall and reduce the dosage of concrete, what’s more, it has high security. But the earth pressure distribution of pressure-dispersed retaining wall is complex as the lateral restraint applied, it still remains unclear for this kind of retaining wall, and the defect of the ultimate bearing capacity theory of anchor-plate restricts its development. In order to study the earth pressure distribution and the influencing factors of the ultimate bearing capacity of anchor-plate, this paper designs a series of laboratory model tests and numerically analyses the earth pressure distribution at wall back and anchor-plate front under prestressing force and cover load. On this basis, this paper reveals the influence of filling material parameters, cover load and anchor-plate size to anchor-plate ultimate bearing capacity. Combined with the limit equilibrium theory, the mechanical model of the anchor-plate was founded, and the calculation formula of ultimate bearing capacity of the anchor-plate was derived and verified by means of numerical simulation. The main conclusions are as follows:1. The distribution of back earth pressure presents a shape of "S" with overlying load applied because of the constraint of lateral anchor plate when there is no prestressing force applied, the peak pressure occurs on the anchor location, the peak of the back earth pressure has an approximate linear relationship with overlying load.2. The distribution of back earth pressure presents a shape of "arch" with lateral prestressing force applied, the peak pressure occurs on the anchor location as well, the peak of the back earth pressure and prestressing force level are approximate linear increased.3. The transverse sphere of influence of the anchor plate under the lateral load is about 2 times of the length of the plate. As for the shallow buried anchor plate studied in this paper, the failure mode of what is shear slip, hence a new type of anchor plate structure is put forward based on this result, which can significantly improve the ultimate bearing capacity of anchor plate.4. The major influence factors for ultimate bearing capacity of anchor plate are properties of filler, overlying load and size of anchor plate, mathematic relation between these factors and the ultimate bearing capacity is built. The ultimate bearing capacity equation of anchor plate is inferred according to ultimate balance theory, what’s more, the rationality of it is verified.