How does Hangzhou Bridge Pile Underwater Testing Construction Company charge? - How much does it cost for professional diving testing of bridges? - Highway Underwater Foundation Testing Professional Company

The construction work of this project is carried out by Jiangsu Huahang Underwater Engineering Co., Ltd. Thank you for the trust and support of the leadership!

How does Hangzhou Bridge Pile Underwater Testing Construction Company charge? - How much does it cost for professional diving testing of bridges? - Highway Underwater Foundation Testing Professional Company

The Yellow River Bridge is a domestic cable-stayed steel structure bridge spanning the Yellow River, with a length of 2817 meters. The major overhaul of the bridge in this project naturally requires underwater pile foundation testing and exploration operations. The Yellow River not only flows fast, but also has a high sediment content. It can be said that when divers work underwater, they must overcome numerous difficulties. The leader of the hydrological station told us that the flow rate of the Yellow River is very small in winter, with a flow rate of 3 meters per second in summer, making it impossible to work underwater. However, the flow rate in winter is also 1.6 meters per second. We have a great responsibility on our shoulders, but we are not afraid of hardship, fatigue, dirt, or cold. This is the essence of Jiangsu Huahang people's broad mindedness. They work hard without hardship. Since the leader has entrusted us with the arduous task, Huahang people not only need to complete it, but also need to use their special skills to press the bottom of the container for construction.

Most of the underwater foundation piles of bridges are always below the water level, and are normally affected by the depth of the water body, making underwater foundation testing quite difficult. Routine inspections are not visible, resulting in some diseases not being detected in a timely manner and missing the opportunity for maintenance and repair, often leading to serious consequences. In order to better understand the underwater foundation condition of bridges and provide first-hand information for bridge maintenance and repair, the Tangshan and Tianjin Bridge Maintenance Management Offices have signed a 10-year underwater inspection camera contract with our company to conduct underwater inspection cameras on submerged bridges.

The bridge has a total of 4 abutments, and we have one abutment per day. There are 11 pile foundations under each abutment, with a diameter of 1.5 meters and a water depth of over 9 meters. When checking the base of the piles, we have to be careful. Divers only need to stay at the bottom for 2 minutes, and the mud will cover their calves. We must notify the surface workers in advance, pull the safety rope, and lift the diver up.

After a period of operation, bridge pile foundations may experience serious phenomena such as foundation hollowing, tilting, pile foundation sinking, and concrete damage due to poor concrete foundation quality or long-term erosion caused by water flow, resulting in exposed steel bars, corrosion, and cracking. Serious accidents have occurred on the bridge. With a pragmatic attitude, various personnel such as divers, cameras, video transmission lines, thickness gauges, underwater lighting, and detection computers are employed. The underwater inspection of pile foundations requires the camera to be rotated clockwise from top to bottom. Divers should move slowly underwater and not miss any place. When steel bars are exposed, various personnel on the water surface must be notified to make records. Our company is a technical company specializing in underwater operations such as diving and underwater plugging, dismantling, installation, rescue, search and rescue, plugging, maintenance, drilling, salvaging, filming, exploration, reinforcement, welding, cutting, dredging, testing, inspection, leveling, etc

Considering the fast water flow, we used two sets of counterweight blocks, tied around the diver's waist, and then fastened an 80 pound iron block with a rope and threw it into the water. The diver went down the rope to explore and inspect the bridge pile foundation, two air compressors, and oxygen supply pipes for the diver to breathe. One set can be used normally, and the other set can only be opened for emergency use. The two air compressors were connected in series, and a reflux valve (professional term) was installed between the pipes to prevent gas from flowing back to the air compressor. Due to the fast water flow, transport ships cannot safely dock around the pier, and can only use cranes on the bridge deck to transport equipment and personnel to the pier. This winter is really cold, with the north wind whistling loudly. No matter how cold it is, I still have to work. A man must have the appearance of a man sweating.

Management of diving operators for bridge underwater pile foundation testing: All diving operators must hold a valid "diver certificate" before conducting diving operations, and special diving operators should also hold a special operation certificate. Before diving operations, divers should be given appropriate rest time, and the interval between deep dives is generally set at 12 hours or more after one dive. During this period, diving is generally not allowed again, except for special emergency tasks, but the interval between two dives should not be less than 2 hours. When depressurizing, the two diving times should be combined to choose an appropriate depressurization plan. Before diving operations, divers should not overeat or engage in vigorous exercise, and the tasks should be clearly defined; After the diver is dressed, they can only enter the water with the permission of the diving leader. They are not allowed to dive without authorization. When diving underwater, the diver must report the underwater situation to the person in charge of the surface telephone at all times, and the communication must be clear. Divers must strictly follow the requirements of the water command personnel during underwater operations, and are not allowed to carry out operations outside the task without authorization. However, in case of sudden events, they must report to the surface in a timely manner and leave the water in a timely manner; After the diving operation is completed, divers should rest appropriately. During the rest period, they are generally not allowed to engage in other physical work, except for emergency tasks. Divers may refuse diving operations if they feel tired or unwell.

How does Hangzhou Bridge Pile Underwater Testing Construction Company charge? - How much does it cost for professional diving testing of bridges? - Highway Underwater Foundation Testing Professional Company

There should be a designated person to give unified instructions for each diving, and all personnel must obey the orders and decrees. Playing and teasing are prohibited during working hours. The signal rope trachea is held by a dedicated person, and the rope and tube must not be removed from hand. Carefully monitor water area news and pressure changes. Strictly and timely keep diving records. Kind preference for the static state of divers underwater. Try to reduce the workload of divers underwater as much as possible. Non mission personnel are prohibited from entering diving workboats. Divers conduct bridge pile inspections while diving assistants record each pile number for easy data organization in the future. Encountering unexpected situations during the first diving operation requires calm handling.

Highways play an increasingly important role in our daily lives, and our daily clothing, food, housing, and transportation cannot be separated from the transportation industry. A highway has hundreds or thousands of bridges, and regular underwater inspections are necessary to avoid dangerous situations such as exposed steel bars and large amounts of concrete peeling and corrosion on bridge piers and foundations. Before the inspection, safety measures should be formulated according to the on-site environment, personnel qualifications and equipment should be verified, and diving helmets, communication equipment, and emergency diver equipment should be inspected item by item according to the table before diving. Ships are required to inspect the highway super large bridge, and our company has its own ships to provide convenience for the inspection work.

The pile foundation tested this time is mainly for underwater exploration. After all, the Yellow River water is very turbid and has been like this all year round. After divers enter the water, they inspect the pile foundation clockwise from top to bottom and conduct a physical examination. From 1 meter to 9 meters, the frogman dives continuously and records the situation of the bridge's piers, pile foundations, abutments, and other parts through handheld cameras. They communicate with the personnel above in real time to inspect the underwater parts of the bridge. The underwater foundation of the Yellow River bridge is subject to water flow erosion and unknown floating object impact all year round, inevitably resulting in common diseases such as defects, holes, cracks, etc. For the underwater pile foundation structure of the bridge, we adopt a joint inspection of both above and below water, with 'frogmen' carrying professional testing equipment to dive into the water and explore the pile foundation of the underwater structure.

Underwater detection camera probing process

(1) Before homework: The central security team, technical team, equipment team, and production team need to arrange personnel to be on site to cooperate.

(2) Test the safety facilities to ensure they are in good condition and ready for use before entering the water.

(3) After diving to the bottom of the water, divers first use underwater lighting equipment to explore and inspect the bottom of the pier and the surrounding area of the pile foundation.

(4) If local damage, deformation, cracks, etc. are found during the inspection, they should be described in detail and cleaned if necessary. In addition to measuring the shape of the damage, straightness measurements of the components should also be added to the damaged area for the purpose of illustrating the measurement results with accompanying drawings. At the same time, divers should take underwater cameras to capture them.

(5) Conduct erosion inspection and riverbed section inspection, and record the inspection data in a timely manner.

2、 Diving gas management for bridge underwater pile foundation testing: Ensure that divers use fresh gas, and there should be no mechanical exhaust gas or other pollution sources that may cause air pollution at the air compressor inlet. The gas supply to divers shall be calculated at atmospheric pressure and shall not be less than 8 kilograms per minute. The purity of the air supplied to divers shall not be less than 98%, and the oxygen content shall be between 20-22%.

3、 Requirements for the diving operation site environment of bridge underwater pile foundation testing: Before diving operation, it is necessary to understand or familiarize oneself with the underwater operation environment, and be clear about the obstacles that affect diving operation, such as fishing nets, floats, etc. Try to avoid night work as much as possible. If night work is necessary, sufficient lighting should be provided; Lifting and other operations are not allowed above the diving operation area

4、 Emergency management of underwater pile foundation testing for bridges: Each diving operation must be customized with a diving emergency plan based on the content of the operation, which should be jointly customized by the diving team leader and divers; The diving emergency plan should cover all diving operations and be mastered by all operators.

After diving, the diver immediately tells the surface by phone. After diving, increase the ventilation appropriately. Strictly adhere to surface instructions throughout the entire diving process. During the entire diving process, any signal received on the water surface, whether from a mobile phone or a rope, must be responded to correctly and promptly. If you feel extremely uncomfortable or uncomfortable during the entire diving process, you should promptly notify the surface. When working underwater, be careful not to lower it below the chest position. It is strictly prohibited to release the messenger rope underwater.

Before rising, it is necessary to inform the water surface in advance, and only after obtaining permission to release the water can it rise from the bottom. Strictly follow the pressure reduction procedure notified by the water surface to release water. It is strictly prohibited to hold your breath when ascending. When approaching the water surface, reach out to protect the roof. The ascent speed shall not exceed 8 meters per minute. Cold water baths are prohibited after unloading, but the temperature of the bath water should not exceed 37oC. Sports activities and heavy physical labor are prohibited within 12 hours of unloading. Do not sleep immediately after exiting the water. The above are the things we need to do during diving operations. Underwater exploration work is dangerous. We must cherish life and do a good job in safe diving operations.