| Since the reform and opening up,the China’s transport industry has experienced rapid development,however many bridges faced the problem which cannot meet the traffic or navigation requirements.The vast majority of these bridges’ carrying capacity still meets the requirements,and demolition and reconstruction will cause great waste.Thus,the emergence of jacking up technology provides a new way of thinking for solving this problem.The researches on lifting reconstruction of bridges at home and abroad are more common in the simply supported girder bridge and continuous girder bridge.However,there are few reports on the lifting reconstruction of Ⅴ-shaped pier continuous rigid frame bridge.Based on the actual engineering project,this paper has done the simulation analysis on the key working conditions of a Ⅴ-shaped pier continuous rigid frame bridge in the process of jacking-up,which has mainly completed the following work:(1)Combined with the development status of V-shaped pier continuous steel bridge,the necessity of bridge jacking transformation is analyzed.Then,the composition and working principle of the jacking system are introduced,and the technology of jacking up for V-shaped pier continuous rigid frame bridge is put forward.(2)Based on the actual engineering,the finite element model of the V-shaped pier continuous rigid frame bridge and the local piers is established.The bridge is simulated and analyzed according to the following conditions:①The bridge state before jacking-up;②In the process of lifting the 4#pier and release the restraint;③The 5#pier is cut during the lifting process and the residual restraint is released;④The bridge is jacked up to the place.This paper compares the stress state of the bridge under the different top force distribution of the jack in the process of jacking up,and puts forward a reasonable distribution of the jacking force.And the effects of asynchrony during jacking up and the change of the temperature on the structure are discussed.(3)After the bridge is lifted in place and the pier is connected,the safety of the upper Part of the bridge is checked according to the existing codes,including the durability of the endurance carrying capacity limit check,Persistent state of the normal use of the limit state of the calculation and durability of structural stress calculation.And the internal force distribution of the pier bottom and the bearing of the bridge before and after the jacking uplift and the self-vibration characteristics of the bridge. |
