Experiment And Analysis On Cable-Pylon Anchorage Zone Of Malinghe Super-Bridge

The anchorage zone of pylon is the key part of the cable-stayed bridge. The stress distribution of anchorage zones is very complicated, because there are many influence factors. The anchorage zone of tower is also the difficult and important part in designing and constructing of cable-stayed bridge. In the designing, simple mechanical analysis and general plane analysis can't reflect the actual stress distribution. Because of the irregular shape of the anchorage zone and powerful local concentrated forces, the design of anchorage zone is rather difficult. The existing bridge norms don't make specific provisions in the design of it. Therefore, analysis of stress distribution at the anchorage zone of cable-stayed bridge has been attracted attention in bridge engineering all the time. Malinghe super-Bridge in Guizhou Province is taken as an engineering example in this paper. It is a concrete cable-stayed bridge with double towers and double cable plane. It is also an example of the application of U-prestress wire to anchorage zone of tower for cable-stayed bridge. In order to master the design of presrtessed anchorage zone of tower, the capability of anchorage zone and the stress distribution of this region, we make a full-scale model test of anchorage zone.Using finite element analysis software,ANSYS, analyze the segment anchorage zone (B22/A22 stage),and obtain stress distribution of it. On the basis of the analysis, we design the full-scale model: the height of the model is 1.61 meters, and the asymmetric polygon section of the model is 6.5*4.5m.In the test we only consider the horizontal force of cable. We make a full-scale model test of anchorage zone. Experiment and FEM analysis show that: the anti-crack safety coefficient is 1.3 and crack opening safety coefficient is 1.6, so the structure is demonstrated safety. Because the section of the model is unsymmetrical, the broken-line long side of the model and the cable anchorage zone are easy to appear stress concentration. So these positions should been given special attention and strengthened.