| In order to analyze vertical bearing behavior of belled pier foundation, three groups of project examples of belled pier in different engineering geological conditions are chosen. Three-dimensional non-linear finite-element numeric model are established, it finds that calculated and measured results approach well. It proves that the establishment of finite-element model and the choosing of calculation parameter are rational, if belled pier with different behaviors are calculated through previous manner, the results will match actual project, at the same time, if the calculated results are analyzed, analyzing results of bearing behavior of belled pier are correct.Three groups of numerical model of belled pier with different dimension are established. It will analyze bearing behavior of belled pier under different length of pier shaft, different diameter of enlarged bottom and height of circle arc of enlarged head. The development procedure of side friction and end resistance with different length of pier shaft is analyzed, then the influence to bearing capacity and pressure below pier which is created by enlarged end and height of circular arc of the enlarged head will be analyzed. It found that bearing capacity of belled pier will increased along increment of length of pier shaft, but the amplitude variation is small, but bearing capacity will increased obviously along increment of bottom diameter of pier diameter, it presents linear relationship. Although the increment of bearing capacity effected by the height growth of circular arc of the enlarged head is not notable, it is necessary to increase the height, on the one hand, better economic returns can be achieved, on the other hand, stress concentration on the edge of the bottom of pier can be decreased. So the bottom of enlarged head should be designed to circle arc, the ratio between height of circle arc and bottom diameter should be defined by different soil property and construction conditions and so on. Generally, the ratio can be choosing around 0.3.Suppose homogeneous soil has same conditions except for modulus, internal friction angle and cohesion force, three groups of finite-element models are... |
