With the continuous development of science and technology and economy, various cross-river and cross-river bridges continue to appear. Wuhan Yangtze River Bridge is the first Yangtze River bridge built after the founding of the People's Republic of China, and is also one of the important historical landmarks in the country. By this year, the bridge is 66 years old. But did you know that the Wuhan Yangtze River Bridge has been hit more than 70 times in history due to navigation conditions and ship driving, most of which occurred in the 90s of the 20th century. But even so, to this day, the whole bridge is still sinking without displacement. Bridge experts have said that after scientific maintenance, the bridge, which was originally designed to have a life span of 100 years, can be used for another 50 years. The first bridge of the Yangtze River stands tall, with the pride of China's infrastructure, and also has the escort of the active collision avoidance system. Not long ago, the Wuhan Yangtze River Bridge carried out a real ship test of the bridge's active collision warning system, and achieved a complete success. How does this system give early warning?To prevent big ships from hitting the bridge, what is the "artifact" of the first bridge of the Yangtze River?
How busy is the Yangtze River waterway?Is there a high risk of a boat hitting a bridge?
Before understanding the bridge active collision warning system, we must first understand the Yangtze River trunk channel where the first bridge of the Yangtze River is located. How busy is this shipping lane?And how high is the risk of a ship hitting the bridge?The Yangtze River trunk channel, from Yunnan Shuifu Port to the Yangtze River estuary, has a total length of more than 2,800 kilometers, with a huge volume and busy navigation. The reporter learned from the Yangtze River Shipping Administration that in the first 11 months of this year, the cargo throughput of the Yangtze River trunk port accumulated 35200 million tons and container throughput reached 23.79 million TEUs, a year-on-year increase. 1%, both record highs. The ship flow is large, and the probability of passing through the bridge is also high, so how big is the risk of the ship colliding with the bridge?
Sun Yuguo, Deputy Director of the Marine Department of Wuhan Port Area:The average daily ship flow in the Wuhan section of the Yangtze River is about 400 times, and there are about 140,000 ships throughout the year, so the ship flow is relatively large, and the probability of ships passing through the bridge is also relatively large, and there is a risk of ships colliding with the bridge.
The reporter learned from the Wuhan Maritime Safety Bureau that taking the Wuhan Yangtze River Bridge as an example, since it was completed and opened to traffic in 1957, the Wuhan Yangtze River Bridge has had more than 70 ship collision accidents, most of which occurred in the 90s of the 20th century. Later, with the improvement of ship condition, crew driving ability and navigation conditions of the waterway, there were fewer and fewer ship collisions on the Wuhan Yangtze River Bridge. However, in recent years, with the rapid development of shipping on the Yangtze River, the tonnage and navigable density of ships are increasing, and the risk of ships colliding with bridges still exists.
Zhang Fan, Deputy Director of Wuhan Maritime Safety Administration:In the process of sailing, if the ship suddenly encounters strong winds, fog, heavy rain, or encounters a sudden increase in the flow speed during the flood season, then in such a situation, a slight careless operation is very likely to cause water traffic accidents.
What are the functions of the bridge active collision warning system?
There are a total of 11 cross-river bridges in the Wuhan section of the Yangtze River trunk line, of which there are 6 bridges in the 18-kilometer water area of the core area of Wuhan Port, which is the largest "bridge group" in the middle and lower reaches of the Yangtze River. At present, all six bridges are equipped with an active collision warning system. So, what are the specific functions of this active collision avoidance warning system?
Li Jia, senior engineer of the Yangtze River Communications Administration:Its function is mainly to remind the sailing ship to have three hidden dangers to prevent in time when passing through the bridge. The first is a yaw behavior of its navigable ship, and if the ship yaws, it may be at risk of colliding with the bridge pier. The second is the super-height of the ship. We know that every bridge has a certain amount of clearance, navigable clearance. If the navigable clearance is exceeded, there is a risk of hitting the bridge. The third possibility is that these ships are in our bridge area, and it is not navigable according to some established navigation rules, such as it makes a U-turn, berths and so on.
Li Jia introduced that the ship collision bridge is mainly yaw, ultra-high and not according to the rules of the three situations, therefore, the system will take the initiative to monitor the ship that is about to pass through the bridge in these three aspects, once found that there is a risk, will immediately carry out early warning.
Li Jia, senior engineer of the Yangtze River Communications Administration:First of all, the most intuitive warning is that the bridge is equipped with a strobe light and a tweeter, once the warning is triggered, the first strobe light and tweeter will sound and keep flashing, so that the crew driving the ship will see the alarm signal on the bridge for the first time, it will cause him to be alert, this is the first layer. The second layer is from the sound, each ship has a corresponding radio station, this radio station is required to be on duty when it is navigated. Then our system will broadcast the warning information in the first time on the VHF channel 06, and the crew will take the corresponding rules to adjust the navigation by themselves.
If the relevant ship still does not respond after the light and radio reminder, the owner of the bridge can notify the traffic management department and the water management department at the first time through this early warning system, and take corresponding emergency measures in accordance with their respective responsibilities, such as sending the nearest patrol boat to the relevant ship to deal with it, so as to prevent the accident of colliding with the bridge.
How does the bridge active collision warning system work?
In order to test the function of the bridge's active collision warning system, the Wuhan Maritime Safety Bureau arranged a field test. At the command of the crew, a cargo ship began to deviate from the normal course through the Wuhan Yangtze River Bridge.
Li Jia, senior engineer of the Yangtze River Communications Administration:We divide the yaw warning zone on the electronic map, and the yellow one is our warning zone. As long as it travels to the yellow area, the automatic identification system equipped with the ship will send its position signal to our system in real time, then we think that it has deviated from the main channel, and there will be a certain risk of collision with the bridge piers when it sails in the yellow area.
Li Jia introduced that a set of radar equipment is also installed on the bridge, which will also scan and locate the position of the ship. If the automatic identification system installed on the ship fails and cannot send a location, the radar equipment on the bridge can also act as an insurance policy.
Soon after the test cargo ship was yawed, the active collision warning system soon discovered the yaw behavior of the cargo ship, and then the warning lights installed on the Yangtze River Bridge began to flash, and the radio station on the test cargo ship also received a yaw reminder from the system. After receiving the warning, the test cargo ship began to correct its course, and when it returned to the correct course, the system alarm was lifted.
How can the early warning system judge "super high" at a "glance"?
In addition to judging yaw, there is also a collision risk that the ship is extremely high. For ultra-high ships, how does the bridge active collision warning system predict in advance?Experts told us that a lidar device will be installed on the bridge to scan the ship in 3D and calculate the length, width and height of the ship. In addition, through the water level gauge at the bottom of the bridge, a beam will be emitted to the water surface, so that the real data from the bridge to the water surface will be measured. If the bridge can only pass 30 meters of boats, but the height of the two data measurements exceeds 30 meters, then the system will effectively remind and control the ultra-high ship through sound and light alarms. Experts said that compared with the past, which could only rely on the human eye to judge whether the ship is super high, this system has greatly improved in accuracy and efficiency. With the application of new technologies, early warning systems will become more and more effective in issuing early warnings of dangerous behaviors of ships, but we also call on pilots to sail cautiously to ensure the safety of bridges and waterways.
**: CCTV news client