Coefficients of Soil Reaction for Buried Flexible Conduits

A study is conducted to examine the parameters governing the coefficient of soil reaction kn normal to the surface of conduits as well as the coefficient ks tangential to the wall surface, and simple formulas are developed for their evaluation. Both circular and elliptical conduits are taken into consideration, as well as two types of soil, namely very dense and medium-dense fillings. The coefficients of soil reaction are obtained by relating the results of internal force components and conduit deformations calculated with rigorous finite element analysis to equivalent results obtained from the system modeling of the problem. The results show that the coefficients of soil reaction vary considerably around the conduit. They are dependent on the span of conduit, the depth of soil and the direction of action.