Research On Performance Of Bearing Capacity Of Single Bored Pile In Loess

The paper deals with the load distribution law and the development of side resistance and end resistance of single bored pile in loess under vertical load through a great number of tests in field on single pile employing some advanced equipments such as sliding micrometers. Some examples are given to demonstrate the application of these laws into optimization design of piles.The load transfer function derived from the in-situ test data can be described by a hyperbolic model. The parameters involved in the model are discussed. Variation of the load transfer function with the structure strength of loess and the state of applied stress are analyzed.Through comparison of the calculated and measured parameters, the modification coefficients of construction process kc1, kc2 and the modification coefficient of depth are introduced, so that the calculated parameters are in well agreement with the measured one. Adopting the deformation harmony theory, the numeric calculation of the curve of load versus settlement is made. The fitting results between the calculated curve of load-settlement and the measured one of piles with different construction process are illustrated. Hence, under the condition of few or no static load test data, the performance of bearing capacity of single bored pile in loess may be predicted utilizing indexes of shear wave velocity, static cone penetration test and modification coefficient of depth, so it is remarkable to reduce the blindness of preliminary design of pile.In addtion, the problems existing in the present tests in field are probed, some solution to which are provided.