| In Recent decades,a large numbers of long-span reinforced concrete arch bridge,steel tube concrete arch bridge and steel arch bridge has been built in our country,The main arch ring stent cast-in-situ method,cable hoisting system commonly used construction method,method of cantilever construction method,construction,strength the skeleton method,The construction method in construction technology and economy aspects exist deficiencies.Abroad mostly adopts the cantilever construction of large span arch bridge method and the cantilever and strength the skeleton group legal construction,not only good structural integrity,but also can advance the final closure,and the requirement to hang buckle system is low.Based on the span length of 420 m net chongqing wanzhou Yangtze river bridge as the prototype,carry out the long-span steel arch bridge construction stage and mixing the main arch ring control technology research.①The main arch of the steel-concrete composite structure,for single box and three rooms reinforced concrete arch in two arch on each side of the range of 100 m,using single box three rooms steel box structure in the cross range of 200 m,a 10 m transition section is arranged between the concrete arch box and the steel arch box.The main arch ring is divided into two side box and a box,two side arch box adopts concrete segment construction technique of cantilever casting method,adopting cable hoisting system installation method with two side steel box.After being two side box closure,from arch foot to vault symmetrical pouring concrete floor and roof,symmetrical intermediate steel box floor and roof installation,complete the main arch ring can eventually form.②ANSYS software is adopted to establish the main arch ring construction simulation,based on a tensioned cable and back way,through the cable tension in the numerical simulation of construction and demolition,to control the tensile stress in the construction process of concrete section and the tower deviation,To study in the process of the arch ring construction stress and the linear variation of the control section,and compared with an arch internal force and deformation.③Study the main arch ring box section in different impact on the internal forces of the main arch ring construction order.Here four different construction scheme is worked out,to the analysis on the internal forces of the main arch ring section and linear effect,find out the reasonable construction scheme. |
