Analysis And Experimental Study About Extended Structure Of Bridge

As our economy has developed rapidly lead to transfer of population and goods are accelerated. the first superhighways and many low grade highway will not be able to meet need in traffic, so its need to be rebuilt or expanded.At present some highways have been widened, when many small spans bridge have been extended, interactional effects between new part and old bridge became the most important problem, such as crack, slab staggering and edge failure. Drive uncomfortable and the unsecurity were created. Both overall structure of the strength and local of the strength are controlling element. According to WangYuanGou Bridge which lies in LianHuo highway, the paper makes a systematical research and experimental study about box girder's loaded performance and connection form in expended P.C. continuous box girder bridge.Through the analytical method of finite element, difference of creep and shrink of old and new concrete and difference of new or old bridge foundation unequal settlement is analyzed among new or old bridge connection interface and original girder. And through the load test, It is surveyed whether WangYuanGou Bridge extended old part of strength is improved. Finally some reasonable suggestion are given from the view point of constructing and designing.The results show that structure of strength is improved through delaying the jointing time; new and old bridge connection of force is the minimum with new bridge foundation nonlinear unequal settlement. Theoretically, by adopting double pier of new bridge foundation is more reasonable; test results show that old part of WangYuanGou bridge of stess have a certain degree of improvement.