Experimental Investigation Of The Model And Analysis On Two-hinged Flat Arch Bridge

Arch bridge is a kind of bridge with long history and vitality. Compared with other ordinary bridges, arch bridge has not only elegant figure but relatively great crossover capability. As a special bridge type, arches transmit the applied loads to the supports primarily through axial compression in the arch ribs while bending moments are relatively small. This decreases tensile stress of arch section and leads to the possibility of fully use concrete material with inferior tensile property and superior compression resistance. The main bridge of Dalian Quanshui No.4 Bridge is a box-section prestressed steel concrete two-hinged flat arch bridge with 88m span and 1/12 rise-to-span ratio. This bridge is very beautiful and it will add beauty to Dalian after being built.The main bridge is special in its scarce rise-to-ratio of 1/12. The main girder has a section of single-box five-cell. The bridge deck is wide and there are horizontal curves. So its internal force is complicated. Though the curve included angle of the bridge is only 8.05? there are little research data or achievement on curve arch bridge at home and abroad. Based on computational theory of arch bridges, finite element and similarity theory, this paper has put emphasis on model test and theory analysis of Dalian Quanshui No.4 Bridge. The detail as the following:Based on similarity theory of model test, the space Perspex model for the global structure is established. Under the condition of the experiment effects, the actual bridge is computed by FEM plane frame. Also the measuring point and load case are defined. Under every kind of load case, the strain and deformation of critical sections are compared between experiment and numerical solutions. The structure verification coefficient is computed and through the strain change curve for bridge wide direction, the bias load coefficient for box girder is also computed. According to the computing results, some helpful suggestions are drawn for other similar bridges.A space FEM model is established with MIDAS/Civil software. Then the result of the model is checked by ANSYS. The influence surface and live load application are computed with ME)AS software, and the computing result is compared with that of simplified model of FEM plane frame. Through analyzing the effects stressed under plane bending, it is proved that the FEM plane frame model for this bridge is feasible.