Simulation Calculation Of Arch Rib Hanging Construction And Aseismic Analysis Of Large Span Arch Bridges

Along with the ceaseless development of large span arch bridges in our country, cablehanging construction without scaffolding of arch rib obtains more and more applications inrecent years, and the analysis of reasonable arch rib closure state also more and more becomesthe key of the construction control. The arch rib hanging construction of large span archbridge is a complex process, in order to guarantee the final bridge line-shape and the forcingcondition satisfying the design request, it needs to use the construction control simulationcalculation. As one of lifeline projects, the destruction of large span arch bridges creates hugedifficulty to earthquake relief, aggravates parasitic infestation, so it is very necessary to carryon the aseismic analysis of large span arch bridge.This article take some large span outside leaning arch bridge as the project background,carried on the research as follows:(1)This thesis takes large-scale analysis software ANSYS as the platform, and uses thenormal direction analysis method, simulates arch rib hanging construction process of the archbridge, works out the corresponding ANSYS order flow.(2) This thesis introduces "the element birth and death technology" into the arch bridgeconstruction simulation analysis process, builds up the whole bridge hanging constructionmodel at one time. In the later each stage structure analysis, kills or alives correspondingconstruction section through the life and death switch, so as to complete simulation analysisof the entire construction process.(3) Aiming at the difficult problem of adjusting cable times and the method limit in jackcable-stayed suspension system, this thesis introduces the optimum analysis theory into archrib hanging construction computation of arch bridge, uses the first order analysis method todetermine the arch bridge reasonable construction condition, analyzes the cable force and archrib hanging elevation in each construction condition, simulates the arch rib hangingconstruction process.(4) On the basis of analyzing reasonable cable force with optimum analysis theory, Thisthesis amends the objective function, studies cable optimum design of the lowest materialconsumption.(5) This thesis establishes the reasonable analysis model of this bridge, calculates thestructure dynamic property, and carries on the seismic analysis to this bridge with responsespectrum method and elastic time-history method.Some conclusions can be drawn as follows:(1) By introducing "the element birth and death technology" into the arch bridge construction simulation analysis process, solves the tedious repeated modeling problem inanalysis, make the process of construction control analysis of the bridge formalization andmore simple.(2) By introducing the optimum computation theory into arch rib hanging constructioncomputation of arch bridge, the calculated cable force can guarantee the structure forcingcondition always to be in the bound of safety, the constructed and adjusted arch rib line-shapeconformed to the design expectation, moreover the computed cable force has high precision,and it can be the basis of construction control directly, avoided the tedious adjusting cablework in construction.(3) Using multiple steps optimizations analysis method, effectively confirms the reasonablearch rib axis line-shape, at the same time, economizes the cable materials, reduces theconstruction charges, obtaines the better economic efficiency.(4) Establishes the dynamic computation model of some large span outside leaning archbridge, analyzes the dynamic property of the bridge, and analyzes each main section seismicforce of this bridge with response spectrum method and elastic time-history method.