Abstract: The load transfer efficiency of geosynthetic reinforced pile-supported embankment with piles arranged in triangle has been studied based on the concentric circular soil arching model with introduced concept of the equivalent pile cap. First, it is assumed that the soil arching is composed of concentric hemispherical soil arching formed by three piles and concentric semicircular soil arching formed between adjacent piles. The load transfer of 3D concentric spherical soil arching and 2D concentric circular soil arching is considered, based on which the soil arching effect has been analyzed. Then the tensioned membrane area of each pile was divided into six parts, and the load transfer of the reinforced material caused by the overlying fill was calculated according to the hypothetical parabolic settlement of the reinforced material. Finally, the computing method of load transfer efficiency of geosynthetic reinforced pile-supported embankment with triangular pile pattern is deduced by jointly analyzing the soil arching effect and tensioned membrane effect, along with introducing the coefficient ? to ensure the overall vertical stress balance. The validity of the proposed method was verified through a comparative analysis of the existing literature data. It is shown that the calculation results of the proposed method are close to the actual engineering data, which can provide a theoretical reference for engineering practice.

Key words: triangular pile pattern, concentric circular soil arching, equivalent pile cap, pile efficacy