Pile Bearing Capacity Numerical Calculation Method Research Based On Energy Principle

Analysis calculation of pile bearing behavior is one of the important problems in research of pile theory. The calculation results of Traditional theory do not conform well of engineering practice. And correctional parameter of traditional theory is not accurate in practical engineering. Although scholars of domestic and overseas have make further research to design calculation method of pile foundation, there are many disadvantages in not only design theory but also practical engineering.Based on energy principle, this paper discussed the pile bearing capacity numerical method and its practical engineering application. Through analysis of the energy transmission between pile and soil, a new pile bearing capacity numerical method which suitable for practical engineering has been built.Firstly, an in-depth analysis of two kinds of pile side resistance load transfer model, which are elastic-plastic model and hyperbolic model, has been done. At the same time, a new multiple broken line model which taken unloading of pile side resistance into consideration has been proposed. The energy transmission between pile and foundation soil has been analyzed. Through energy balance equation of pile unit, the energy difference equation which is needed by pile bearing capacity calculation program has been proposed.Secondly, based on the energy difference equation, a calculation program has been given. And two different convergence condition, which are load convergence condition and minimum potential energy convergence condition, have been proposed. At the same time, program strategies and calculation process of both convergence conditions have been given. Through calculation results study of a practical engineering example, the applicability of program and rationality of program strategies have been proved.Thirdly, according to the pile negative friction problem, foundation soil settlement has been taken into consideration. That makes the program suitable for general condition. Pile-soil relative displacement computational item is introduced in pile energy difference equation. And a pile bearing capacity calculation program which taken foundation soil settlement into consideration has been given. Through calculating a practical engineering example, rationality of this program has been proved.At last, for investigating the practical application effect of program built in this paper, it has been used to analyzing maocaojie bridge pile static load test results. The main data of the static load test results has been given. Using the program method built in this paper, the pile bearing capacity and settlement have been analyzed. The results of program agree with the measured data, show that the pile bearing capacity analysis program is suitable for practical engineering application.