大跨度钢-混凝土连续组合梁桥施工过程有限元分析-防灾减灾工程及防护工程专业论文.docx

Abstract There is negative bending moment nearby the middle supports of continuous composite beam bridge, and the cross-section is at a disadvantage stress state. The floor deck concrete in these regions withstand greater tensile stress, and it will crack. Then it will cause the corrosion of the steel-bar and steel beam, affect the bearing capacity and duration of structure. The steel beam in the region of negative bending moment withstand pressure, so we should pay attention to the stable problem. Currently, we always take some reasonable construction measures to improve the mechanical properties of the negative bending moment zone. This paper did a finite element simulation analysis of the continuous steel-concrete composite beams of Wuhan Erqi changjiang river bridge and verifyed the bridge deck and steel girder can meet the design requirements. Then it reviewed the common optimization measures in the construction of continuous composite beam bridge. This paper focused on the the measure of pivot movements, in order to provide some assistance to the design and construction. This paper employed ANSYS program to establish the model of continuous steel-concrete composite beams of Wuhan Erqi changjiang river bridge, then used the measure of live and dead element to simulate the construction process. It gived the concrete deck and girder stress and reaction force in the whole process. Then a comparative analysis of a variety of pivot movements programs is completed in the paper, including comparative analysis of whether the pivot movements is used, different distance of pivot movements and the different order of pivot movements. The results show that, a reasonable pivot movements can significantly improve the mechanical properties of the continuous composite beam bridge with negative bending moment. The concrete deck can reserve a certain compressive stress, while the compressive stress in bottom flange of the steel girder can be reduced. Keyword: Continuous composit