At about 3 a.m. on November 22，Chengtou Highway is responsible for the construction.，Shanghai Donghua Local Railway Development Co., Ltd.、Bid 1 of Caobao Road Expressway New Construction Project undertaken by China Railway 24th Bureau ushered in a key node，The first domestic super-wide asymmetric swivel bridge constructed in this section continuously crosses four railway lines.（Seven railway lines）Achieve successful and precise docking，The three-dimensional asymmetry of the swivel is refreshed.、Widest swivel deck、There are many world records of swivel bridge, such as the widest swivel across the high-speed railway.。

Total weight of the swivel bridgeTons 15800，Overall clockwise“Rotation”110°，Full-width rotation scheme is adopted.，It is the key control project of the new construction of Caobao Road Expressway.。“The cross-iron node adopts super-largeTRotating construction of structural steel box girder，Overpass several railways in operation and under construction，And that construction safety factor is high，The impact on railway operation has been greatly reduced.，The construction period is shortened.。”The relevant person in charge of the District Transportation Commission further explained.，The swivel bridge body crosses the airport connecting line from east to west in turn.（Under construction）、Shanghai-Kunming high-speed railway、Shanghai-Kunming Railway and its realignment（Under construction）Four railways（Seven railway lines），The location of the bridge is just above these railway lines.，The high-speed rail below does not stop running.，It is very unsafe to construct directly.，So，The construction scheme is to prefabricate and assemble the bridge on one side first.，And then“Rotation”To the specified location。

According to introduction，The swivel bridge is 190 meters long.，It is a super-wide and super-high special-shaped three-dimensional asymmetric structure.，The beam width is 40.5m Gradient to 99.3 meters，Liang Gaoda 8.2 meters，Maximum longitudinal slope of bridge deck 6.04%，The maximum height difference between the two ends of the bridge is more than 12 meters.，Center of gravity deviates from pier center 8.7 meters。Length at both ends of the swivel、Weight difference is too large，The conventional rotation mode is difficult to realize，The construction is extremely difficult.，At present, there is no construction precedent at home and abroad.。

Before the swivel bridge

Swivel bridge swivels into position

So what about the bridge?“Rotation”Yes？Introduction of project staff，15800 tons“Behemoth”Was placed in a“Turntable”On it，And“Turntable”It's the swivel system。“Rotation”The principle is similar“The donkey pulls the stone mill”，21. 15.The 2mm steel strand is evenly wound around the circumference of the turntable.，By means of two synchronized automatic continuous traction equipment，Control the swivel bridge with 1.03 degrees/Rotate slowly at a rate of minutes。At the same time，The swivel process is equipped with intelligent swivel monitoring system for real-time dynamic monitoring.，Ensure the safety and stability of the turning process，Achieve precise docking。

Asymmetric in three dimensions、The swivel bridge deck is wide、Under the influence of many factors such as the number of tracks crossing the railway，During the construction of the bridge, the stability and balance control of the bridge deck are faced.，Control of transverse deformation of bridge deck、Swivel process control、Safety risk control and many other world-class construction problems。

In order to solve the problem of three-dimensional asymmetry caused by the irregular shape of the bridge structure,，Construction Team and Tongji University、Wuhan University of Technology Jointly Tackles Key Problems，Use three dimensionsCADCenter of gravity recheck technique、Unbalance Technology of Stress Difference Based on Sandbox、Top force+The data acquisition system of the displacement sensor realizes the balance weight of the beam.。In the process of turning，The project department adopts the real-time early warning system for stress monitoring overrun.、Automatic real-time attitude monitor system for swivel、Anti-overturn automatic early-warning information system，By constructionBIMInformatization model，Real-time dynamic guidance of swivel construction，Safely and accurately guide the steel beam to rotate in place。

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The new project of Caobao Road Expressway starts from Jiamin Elevated Road in the west.，East to Guiping Road，It crosses Songjiang along the line、Minhang、Xuhui District 3，The total length is about 7.18 kilometers，It is the Hongqiao hub“One vertical and three horizontal”Nanheng Passage in Fast Distributed System。As Shanghai“Fourteen five”Planning major transportation projects，The new construction of Caobao Road Expressway will speed up the construction of Shanghai“Four centers”The construction of、Supporting the transformation of urban structure、Improve the backbone road network in Shanghai、It is of great significance to improve the service guarantee of expressway system.。

Schematic Diagram of Caobao Road Expressway Project

The main tunnel and elevated road are urban expressways.，Design speed 60 km/Hour，Two-way six-lane traffic scale。Reconstruct Caobao Road on the ground into urban trunk road，Design speed 50 km/Hour，Two-way 6 fast and 2 slow traffic scale。

The whole line and Jiamin Elevated Road、SThere are 3 interchanges on Highway 20 and Central Expressway，And the west side of Zhongchun Road、There are three pairs of entrance and exit ramps on the east side of Hechuan Road and the west side of Lianhua Road.。

Renderings

Rendering of Jiamin Interchange

Effect drawing of outer ring interchange

Rendering of Central Interchange