Jacking Construction and Measures for Jacking-up of Large Gradient Bridge

Nowadays, more and more bridges are difficult to meet the traffic needs because of the limitations on bridge clearance height while bridge demolition and reconstruction will lengthen the construction cycle, waste a lot of resources, increase the construction cost, etc. By solving these problems and using the original bridge effectively, the bridge jacking-up construction technology is widely used. With the construction of urban road network, the original ramp bridge needs to be elevated to the new main road in the process of viaduct construction in Shanghai, which involves the slope adjustment of large gradient bridge. The jacking section of the bridge with 16.5m width deck and the total length 220.51m is divided into two sections with 19.51+24×3+19m and 19+24×3+19m span combinations. A series of measures are put forward for the bridge jacking construction: the ball-head Jacks are installed to offset Jack deflection, the sliding steel plate is used to ensure vertical and horizontal displacement of the Jack, the push-pull devices are installed to ensure the width of expansion joint while jacking-up and the fast-hardening concrete is proposed to use in the process of pier heightening.