Study for the Pile Foundation on Steep Slope Applied in UHV Transmission projects

When designing a pile on the steep slope, the calculation is based on a hypothesis of horizontal ground. Obviously, it is difficult to estimate the difference between the calculation result and the actual loading behaviour of the pile foundation. For a UHV (Ultra High Voltage) power transmission project in China, results are compared by two kinds of methods. One is traditional theory; the other is numerical simulation method. It shows that quite different deformation of ground foundation occurs near two sides of the pile cap. The traditional calculating method for the pile foundation can consider the effect by increasing the part of the pile above the ground surface. Reasonability of the increased value can be assessed by the numerical method. The result of numerical simulation shows that the maximum deformation appears in the middle of the pile, but it occurs in the top of the pile by the traditional method. And deformation is evidently larger by the traditional method. Deformation curve is different between the traditional method and the numerical method which can consider frictional resistance around the pile. Quite different are vertical stress values of the pile obtained by two methods