Abstract：The Quadra-pot-shape earthworks structure is a reinforced concrete works composed of an upper part of short U-shaped structure and a lower part of hollow box structure which are connected by a shared plate. The novel earthworks structure is suitable for situations of high fill, limited land and soft ground. In order to determine theoretical calculation method of the structure reasonably, earth pressure and additional stress of pavement load on the upper U-shaped part for two earthworks widths are provided based on the limit equilibrium theory in conjunction with horizontal slice method of the fill. Furthermore, the Quadra-pot-shape structure is decomposed logically into a foundation beam part and the part on it. The former can be regarded as a beam on elastic ground which may be solved by Winkler foundation beam model, while the latter can be simplified as a planar rigid frame which may be solved by the force method of structural mechanics. For the analysis of the Quadra-pot-shape structure, deformation compatibility between the foundation beam and the upper structure shall be fully taken into account, and additional internal forces and deformation of the upper part of the structure due to uneven ground settlement can be determined. Besides, overall seismic stability of the earthworks structure is analyzed using the pseudo-static method. Analysis results show that the proposed theoretical solutions are basically consistent with the numerical ones, and internal forces of the structure predicted by the proposed method are about 3%～16% higher than those by numerical simulation method. Additional internal forces and deformation of the upper structure owing to uneven ground settlement shall not be ignored in most cases. In the case that the total height of earthworks is constant,configuration of the Quadra-pot-shape earthworks structure can be optimized by reducing the upper bottom plate, foundation plate and webs as thin as possible, adjusting height of the webs to minimize the sum of the maximum bending moment of the upper bottom plate and foundation plate and controlling the ratio of extension length of the foundation plate at each end to its basic length between the two webs as about 30%.
