Mean Stress Layer Wise Summation Method Based On The Mindlin’s Stress Solution

The research of mechanism of pile foundation settlement is a difficult problem and hot spot in building. The traditional deep massive foundation method and Mindlin solution settlement method have an important limitation of poor precision that can result in large variation of empirical coefficients in settlemet computation that limits its application in engineering with high precision requirment, for example, in strong bridge pile foundation,engineerings with strict differential sedimentation control and so on.Starting with Mindlin’s solution with consideration of the effect of pile diameter, this paper studied the mechanism of settlement of single pile, and proposed the stress coefficients of single piles. The pile groups average stress method is proposed based on this method, and the lateral resistance distribution pattern in different soil layers is sorted out. At last the empirical coefficients of settlement were obtained by comparing average stress layer summation method with real settlement measurement.Following works have been carried out1. The renovation of the single pile stress coefficients is completed, and the stress coefficient tables was reconstructed. The subsidiary stress coefficient is expressed as a function of depth to diameter ratio h/d and pitch diameter ratio ρ/d to describe the spatial variation.2. Based on Mindlin’s solution with consideration of the effect of pile diameter The additional stresses generated by single pile tip resistance, average lateral resistance and triangle lateral resistance are expressed as the product of the resistances and the corresponding stress coefficient.3. In this paper by using Mindlin solution, with consideration of Geddes solution, and assuming that the start point of integral is at a certain depth below ground surface, we obtained the analytical Geddes solution with a certain bury depth. And the new solution is compared with the original Geddes solution. Comparison shows that this method is more precise than the original Geddes solution.4. The average stress layer wise summation method is proposed.