Abstract：With the rapid development of expressway，more and more constructions such as culverts have been built under highly filled embankment. However，the damage and accident occur frequently. The main cause of culvert damage is that the formulas or empirical curves with a smaller copulating result are adopted by some designers to calculate the vertical earth pressure on the top of the culvert. The better way to resolve the problem is to pave the soft material whose compressibility is larger than earth fill on the top of the culvert，and as a result，the earth pressure can be regulated properly. Having studied the mechanical properties of expanded polystyrene(EPS) through experimental test and filled it on the top of the culvert with high embankment to in-situ test load shedding and compared the results，it is found that the deformations of EPS under two conditions are similar. Based on the combining recursive analyses，the empirical formulae to calculated the vertical earth pressure on the top of culvert under given regulation effects are presented. In addition，with the finite element calculation，the effects of the breadth of regulation material on earth pressure of culverts are studied and the propositional numerical values for different shapes of culverts are achieved. Furthermore，the method of rational and measurable height choice，and density and filling breadth of regulation material for given regulation effects，are put forward which can afford references to project design.
