EARTH PRESSURE ON THE TOP OF RECTANGULAR TRENCH-BURIED CULVERTS

Under the condition of rigid culverts and rigid subgrade, the vertical earth pressure on the top of rectangular trench-buried culverts was analyzed theoretically, and a new model and formulae to evaluate the earth pressure are proposed with the consideration of the effect of soil mass beside culverts. The calculated results agree with those from finite element method. The results show that the coefficient of earth pressure decreases monotonously with the increasing depth of soil overlying culverts if trench width equals the outer width of the culverts, while the coefficient increases at first and decreases later if trench width exceeds the outer width of the culverts and the maximum coefficient appears at the depth close to the height of the plane of initial identical settlement. The coefficient increases with the growing of ratio of the trench width to the culvert width and with the increase of high-width ratio of the culverts. It also grows with the increase of the angle of internal friction of the soil. The coefficient decreases as the increasing cohesive strength of the soil. The height of the plane of identical settlement increases as the ratio of trench width to culvert width increases and decreases as the depth of soil overlying culverts increases.