Analysis On Vertical Bearing Capacity Of Friction Pile Foundation Based On The Catastrophe Theory

As the important content of the devise, how to calculate and confirm the vertical bearing capacity of single pile, especially the utmost vertical bearing capacity of single pile is very important. There are a number of methods to confirm the vertical bearing capacity of single pile, but issues appeared when used in engineering adhibitions more or less. The ultimate bearing capacity of friction pile be undertaken by the friction force around pile and the Q ? scurve assume to be a slowly model. The friction force around pile tend towards to be a fixed value with the aumentation of the displacement and attain to the utmost finally. There is no distinct inflexion in Q ? s curve. The soil around piles ttain the utmost equation predicament when the friction force attain to the largest. The mechanics character of piles and the soil around piles transformed abruptly. Based on the cusp catastrophe theory, the calculating formula of the vertical ultimate bearing capacity of friction pile is deduced in this paper. Then use the formula in engineering examples and compared with the practical results, we can get some conclusions.The utmost placement s 0 can be ascertained by the result of hyperbola, and we can get the vertical bearing capacity of friction piles based on the cusp catastrophe theory.The placement of critical point s * can be found by the utmost placement s 0,when s 0 get larger and larger, s * changes with s 0 and get larger and larger either.The results of cusp catastrophe formula departure biggish by the load test when multilayer close-grained thick soil around the piles. We must amend the formula bases the engineering adhibitions. Amend modulus are found according to the engineering adhibitions,and then the formula of vertical bearing capacity of single pile is: (1)22We can get good results when use the formula in flexible land which show that the formula could be used in such engineering adhibitions.