Research On Carrying Capacity Of Prestessed Concrete Hollow-ban Bridge Confined By Carbon Fiber Sheet

Economic development cannot do without the improvement of transportationsystem, if we want to promote the rapid development of economy, we must establishthe perfect, modern transport network. Excellent traffic conditions not only have apositive role in promoting the development of China’s economy, at the same time,improve the traffic conditions in strengthening inter regional differences in economicand cultural exchanges, reduce regional, have far-reaching impact. In the constructionof highway transportation system, bridge engineering occupy a key role. With theimprovement of people’s living quality and transportation business is booming, a largeincrease in the number of motor vehicles and the traffic congestion, vehicleoverloading on the original bridge in load standard design put forward higherrequirements. The building of the bridge is designed according to the old standardappeared carrying disease force is not enough, cracking of concrete bridge, iftreatment is not timely will pose a serious threat to traffic safety, if the demolition andconstruction, a long time blocking traffic, also on the road transport have negativeeffects, but also will damage ecological the original environment, therefore, has beenbuilt on the bridge was not in conformity with the requirements of repair, maintenance,reinforcement and reconstruction has become a scientific and rational choice, whichnot only extend the service life of the bridge, improve or restore the load using thestandard, but also to ensure the smooth transport.Prestressed concrete hollow slab is widely used in small and medium spanhighway bridge construction, the partially prestressed concrete hollow slab cracksappeared in different degrees, in urgent need of maintenance. Therefore, thestrengthening of the old bridge reinforcement technology of prestressed concretehollow slab bridge, plays an important role in ensuring the transportation safety andsmooth.In this paper through the establishment of modeland numerical simulation analysis of the ordinary carbon fiber cloth withprestressed carbon fiber sheet under different working conditions of the stress change, the main conclusions are as follows:(1) by comparing the results of EA numerical simulation results and theoreticalcalculation, it is found that although the bridge under the two kind of reinforcementeffect is similar, but using prestressed carbon fiber cloth reinforcing way than theordinary CFRP way bridge reinforcement effect is better(2) according to the strengthening and hollow plate lower load factor-concreteresults force curve, hollow slab stress state is not in the ordinary carbon fiberreinforced is significantly improved; strengthening using prestressed carbon fibercloth, can significantly weaken the stress of concrete, the suppression of crack.(3) from the cracking load, crack width and other terms, prestressed concretehollow slabs strengthened with carbon fiber cloth is common after effects, obviousimprovement on cracking load and crack width and its development; and theprestressed CFRP prestressed concrete hollow slab, has the function of improvingobviously the cracking load, and has obvious inhibiting effect the width of cracks anddevelopment.(4) from the lower hollow plate deflection, in the same conditions, thestrengthening effect of prestressed carbon cloth than ordinary carbon fibercloth reinforcing effect.