Improvement For Prediction To Loading-displacement Curve Of Single Pile And Implement With Matlab/Gui

In the design of pile foundations, the bearing capacity and settlement property of piles are always the important issues in the research of pile theory. Due to the complexity of pile-soil interaction, the reasonable solution has not been put forward. It is a better solution to discuss the performance of piles with the loading-displacement curves of single piles. The fitting prediction has lots of methods, but their concrete realization processes are different, the accuracies of results are not same. The techniques of fitting and forecasting applying in the loading-displacement curves of single piles still have some defects in the theory of modeling, and the existing implement method is so complex to require programming.In this paper, three analytical methods are used to make the fitting and prediction to loading-displacement curves of single piles:load transfer method, curve-fitting method and the analytical methods by the model grey theory. Besides introducing the fundamental principles and realization steps of these three analytical methods for calculating, some improvement measures are presented for the defects in the theory of modeling:With load transfer method, the new analytical solution that the load transfer functions of the surrounding and underlying soils are both exponential load transfer models is built, then linear and nonlinear load transfer functions are introduced in comprehensive analysis. With curve fitting method, modified exponential curve model is put forward, eight kinds of S type curve model are summarized. Based on the principle of combination forecasting, superposed combined curve and segmented combined curve are proposed. With grey theoretical model, direct grey model DGM(1,1) for fitting and forecasting in loading-displacement curves of single piles is presented, two revised measures to improve grey theoretical model in modeling mechanism, including:optimization of background value and optimization of initial value, and16 improved models are shown.Due to realization of the calculation methods above needs the programming with computer, and the operation is always non-visual, technology of MATLAB/GUI is recommend. Three visual interface programs "Load_transfer"、"curves" and "Greymodel" are thus programmed to be used for engineers and researchers.