Study On The Effects Of Structure Performance In The Construction Process Of Arch Center Cast-in-situ Of Arch Birdge

Box arch bridge has big stiffness and good stability in construction, but also it gainbetter bending stiffness and higher anti-torsion rigidity in box section, as a result boxsection is economic and reasonable section type among long-span arch bridge,especially in the case of great river and deep canyons bridge site. Therefore, insouthwest China where has many of the valley has built a large number of box sectionarch bridge. In order to find a way of more economic and convenient bridgeconstruction, arch construction method born and Bailey arch with its convenient, highstandardization degree in construction and the characteristics of utilization repeatedlybecome a more commonly used arch type.Wengxi bridgeⅡin ZhenXian, GuiZhou, a typical large-span box reinforcedconcrete arch bridge, was completed by the arch cast-in-situ method construction. Incombination with the monitoring work of the bridge, analysis the related problemsfound in bridge construction:1. In view of the arch construction method for cast-in-situ arch bridge，designscheme for monitoring in construction of arch assembled problem and arch ring pouringproblem, etc. Determine the best construction scheme;2. In view of the arch cast-in-situ construction method, combined with the bridgeusing two hinged arch foot Bailey arch, comparative analysis of Bailey arch in differentflat, vertical assembly layout scheme, strengthening bar connects to Bailey chord ofsimulation method and arch foot assembly scheme were analyzed, and the influence tothe stability of the arch and according to the actual construction of arch ring slab castingprocess analysis of the stability of arch. According to the commonly used two kinds ofsimulation bailey and strengthen the connection mode of rod has been simulatedanalysis, two types of simulation on the stability of arch effects were small; connectionstatus of arch foot has a larger effect on the stability of the arch; Stable performance ofthe arch decreases gradually with the increase of the construction load, and the archstability coefficient curve of drawing basic linear distribution;3. In view of two hinged arch foot Bailey arch, combination with monitoringmeasured data, analysis the combined effects in arch ring and center, find that thedesirable45%combined contribution degree; Arch stress measured pace is consistentwith the theoretical value of the corresponding change, better regularity. In this paper,the Wengxi bridge Ⅱ dividing arch ring construction of cast-in-situ arch bridge construction can better reaction to the stress of the real bridge, model analysis andhigher calculation data credibility;4. The stress state is accumulating to form in the section construction of the bridgestructure, eventually into the state of the bridge structure is completed all stages of thestructure of the stress state of the superposition of the results. Combined with modelinganalysis of the methods of one-time-concreting cantilever construction, cantilevererection construction and dividing arch ring construction of cast-in-situ arch bridgeconstruction, can be found: the stress distribution of arch is different on the influence ofthe construction methods; After structure of shrinkage and creep effect, key sectionstress distribution of arch ring tend to be similar in form, the early due to the differentconstruction method by the impact gradually weakened.