Shenzhen’s pulse quickens here at the Chuangye Road Flyover. This isn’t just concrete and steel. It’s a story etched in every span. Opened in 1997, this fully interoperable hub sits where National Road 107 meets Chuangye Road in Bao’an District.
The Chuangye Road Flyover comprises ten directional ramps. These ramps are all bridges. Imagine twenty links. Ninety-six spans. Each ramp bridge curves gracefully with a radius of 70 to 250 meters. Their lengths stretch from 40.4 to 174.4 meters, totaling 1,992.58 meters.
Look up. See the upper structure? It’s a 30-meter standard span prestressed concrete continuous box girder. It features a single box and a single room. The bridge deck spans 7.5 to 17.2 meters wide. The beam height measures 1.30 meters.
Consider the substructure. Pile-column piers support the weight. The foundations are bored piles. Abutments stand as gravity abutments or side cap beams. Most ramps feature single-pillar piers or beam-consolidated piers. These measure 1.2 or 1.5 meters in diameter. The bridge was designed to handle heavy loads. Think car-over 20 and trailer-120.
But time takes its toll. Inspections revealed the Chuangye Overpass was showing its age. The curved beam ends were moving laterally and slipping longitudinally. Limit stops at the beam ends were damaged. Expansion joints failed. The bridge deck between the two bridges was misaligned. Cracks appeared on pier tops, cap beams and corbels. Some ramps relied on tension bearings just to stay operational. The bridge’s technical status was downgraded to Category 3.
A maintenance and reinforcement plan was crucial. Engineers aimed to maintain the highway level. They used reinforcement methods to limit the main girder’s deviation. The goal was to prevent further damage. Common issues were repaired. The principle? Solve current problems. Prevent future ones. The entire overpass bridge was included in the maintenance. Fourteen bridge spans needed reinforcement to varying degrees. The reinforcement covered 1531 meters.
Think about the consolidation pier reinforcement. After reinforcing the pier body, the original foundation bears more weight. So, the original foundation also needed reinforcement. Limited space under Qianqiao Bridge complicated construction. Traditional bored pile foundations were difficult to build. Micropiles became the solution for the foundation.
Joint piers all have cap beams. Reinforcement design used a steel-concrete composite structure cap beam. It was placed under the original cap beam. Concrete was poured to distribute the load.
A limit device was added at the girder end of the main girder. It works with the fixed pier of the middle pier and the abutment cover girder block. This prevents further deviation of the main girder.
Articulated piers and corbels received attention too. They were reinforced with Horse carbon fiber and steel plates. This strengthened and repaired them.
Reflect on the lessons learned. Bridge reinforcement should minimize new damage to the structure. Foundation reinforcement should improve rigidity. Micropile foundations are ideal for limited clearance. Strong consolidation piers effectively restrain torsion. They also minimize deflection of the upper main beam. Steel-concrete composite cover beams strengthen sub-junction pier cover beams. This improves bending, shearing, and punching resistance. Steel pins create effective limit devices. These devices restrain transverse bridge movement. They reduce torque from centrifugal force on the pier.
The Chuangye Road Flyover stands as a testament. It showcases engineering ingenuity. It highlights the ongoing effort. It ensures safety and efficiency in a rapidly growing city.