Vibration reduction device for suspension bridge

In order to serve the construction of cable-stayed bridges designed by Vietnam in the future, experts from the Institute of Mechanics (Vietnam Academy of Science and Technology) have successfully fabricated and tested devices to reduce fluctuations harmful to this type of bridge. .

The devices reduce vibration (vibration energy dissipation) for the cable car of the cable-stayed bridge

In the past, people had to install equipment to reduce fluctuations for each cable of cable-stayed bridges such as My Thuan Bridge and Bai Chay Bridge. Currently, cable-stayed bridges in Vietnam have been built using equipment to reduce import fluctuations.

Recently, experts at the Department of Engineering Mechanics, Institute of Mechanics with the cooperation of the Institute of Mechanical Research and the Ministry of Industry have manufactured devices to reduce vibration for suspension bridges. The equipment has been evaluated for quality on the dynamics system of the Institute of Construction Science and Technology.

After a period of research in the laboratory, with the cooperation of traffic science experts, the device has been tested and applied at Ben Coc cable-stayed bridge (Ha Tay) and Ngoi Rolling bridge (Yen Bai). .

At Ben Coc Bridge, 16 devices were attached to 16 cables, then a car group weighed 12 tons / vehicle running through the bridge. The results show that if there is equipment, when the car runs through the oscillation of the cable, it can be clearly observed with the naked eye. As for wires without equipment, cables fluctuate with a large margin, in the long run will lead to fatigue and cable cracking over time.

According to Prof. Dr.Sc. Nguyen Dong Anh, head of the research team and chairman of the Science and Technology Council, is a device that reduces harmful vibrations for cable cars like a motorcycle shock absorber, including a piston cylinder and high viscosity silicon lubricant. . When the cable or god bridge oscillates, the piston moves in a viscous environment, producing resistance to dissipate oscillating energy.

Fabrication of vibration reduction devices is not difficult, but it is important that the device design has the resistance suitable for each bridge, each cable on the bridge. To do so, the team built the SAVA (Structural Anti Vibration Analysis) software to analyze the vibrations of structures with oscillating energy dissipation devices.

After entering the parameters of the bridge, the device reduces oscillation, SAVA will evaluate the efficiency of the device, thereby changing the parameters of the device to reduce the most effective oscillation. This software is also open for other applications such as vibration analysis for high-rise buildings, marine structures, etc.

According to the assessment of TS. Tran Viet Hung, Chairman of the Program for Scientific Research and Technology Development of Machine Manufacturing - KC.05, technology to reduce fluctuations harmful to construction works that VN technology can do, reduce costs Buy foreign equipment. If invested and developed, Vietnam will quickly update a new technology of the world, draw lessons to apply this technology to other fields such as high-rise buildings, high-speed trains, works. sea

Install vibration damping device for a cable in Ben Coc cable stayed bridge

Finished two devices to reduce vibration for two strands

Deployment of measuring equipment on the bridge

For cars to run through to check the effectiveness of device vibration reduction

Equipment for adjusting cable tension in the laboratory

SAVA structure structure vibration analysis program

Minh Son