Abstract：The bearing mechanism of piled embankments，i. e. stress transfer and distribution in the embankments under the interior and exterior loads，can be represented by soil arching effect. Based on Hewlett¢s soil arching analysis，a more rational boundary condition is assumed when the plastic point begins at the top of the pile cap；an improved analysis method of three-dimensional soil arching effect in piled embankments is proposed；and an analytical solution for pile efficacy is obtained. General expressions are developed giving the load，distribution ratio of pile cap to soil between piles in terms of pile cap size and centerline space，height of the embankment，the friction angle of the granular fill which forms the embankment，and so on. The results of load distribution ratio of piles obtained from Hewlett¢s solution and the improved method are compared in detail. Finally，a practical case is analyzed to verify the feasibility of the improved method.
