Views: 1306 Author: Mick Chan Publish Time: 2025-10-24 Origin: Site
Bridges, as important nodes in transportation networks, are not only physical channels connecting regions, but also links that promote economic development and cultural exchange. Among numerous bridge construction projects, large-span bridges have become an important development direction for modern bridge construction due to their strong spanning ability and beautiful appearance. The hoisting of large-span components is the core link in the construction of large-span bridges, and its construction quality and efficiency directly affect the success or failure of the entire bridge project.
Taking the Hong Kong Zhuhai Macao Bridge as an example, this mega project that integrates bridges, tunnels, and artificial islands faces many world-class challenges during the construction process. Among them, the hoisting of large-span bridge components is a major challenge. The bridge section of the Hong Kong Zhuhai Macao Bridge adopts a large number of steel box girders, which are of huge size and can weigh up to thousands of tons per section. How to accurately lift these behemoths into place has become a challenge that engineering builders must overcome. By using advanced lifting equipment and technology, as well as carefully planned construction plans, the builders successfully completed the lifting task of the steel box girder, laying a solid foundation for the smooth completion of the Hong Kong Zhuhai Macao Bridge. This fully demonstrates the crucial position and important role of large-span component hoisting in bridge construction.
（1） Challenges brought by the inherent characteristics of components
Large span components usually have the characteristics of huge size and astonishing weight. Taking the common steel box girder in bridge construction as an example, its length can reach tens of meters, width several meters, and the weight of a single section is often in the hundreds or even thousands of tons. Such a large size and weight place extremely high demands on the lifting capacity and stability of the crane during the lifting process. In the initial stage of lifting, it is necessary to overcome the static inertia of the components, and the huge pulling force at the moment of starting may cause impact on the structure and transmission system of the crane; During the lifting process, the distribution of the center of gravity of the components is complex, and a slight mistake may cause the center of gravity to shift, leading to component shaking or even imbalance.
In addition, the shape of large-span components is also relatively complex, and it is not as easy to determine the lifting point and perform stable lifting as regular objects. For example, some irregular bridge components may have irregular shapes and internal structures designed to meet the requirements of mechanical performance and architectural aesthetics. This requires precise mechanical calculations and analysis when selecting lifting points to ensure that all parts of the component are subjected to uniform forces during the lifting process, and to avoid damage to the component due to excessive local forces. Meanwhile, the complex shape also increases the difficulty of transporting and positioning the components, making them prone to collision with surrounding obstacles.
（2） The complex impact of construction environment
The terrain conditions at the construction site vary greatly, including complex terrains such as mountains, hills, and water bodies. In mountainous and hilly areas, the terrain is undulating and difficult for cranes to stand, requiring a lot of time and effort for site leveling and foundation reinforcement. If the foundation treatment is improper, during the lifting process of the crane, the uneven settlement of the ground may cause the crane to tilt, endangering the safety of the lifting operation. When constructing bridges in aquatic environments, such as cross sea bridges, cross river bridges, etc., in addition to considering the impact of natural factors such as water flow and tides on the stability of cranes, it is also necessary to build specialized water operation platforms. This not only increases construction costs and difficulties, but also puts strict requirements on the bearing capacity and stability of the operation platforms.
Site conditions are also an important factor affecting the lifting of large-span components. Construction sites often have limited space, with material stacking, mechanical equipment parking, and personnel activities all requiring a certain amount of space, which greatly limits the positioning and working space of cranes. The narrow space may not be able to meet the requirements for the crane to deploy its legs, resulting in the crane not being able to reach its optimal working condition and reducing its lifting capacity and stability. At the same time, obstacles within the site, such as buildings, power poles, underground pipelines, etc., can also affect the transportation and lifting path planning of components, increasing the complexity and risk of construction.
Climate conditions cannot be ignored either. Severe weather, such as strong wind, rainstorm and fog, will have a serious impact on lifting operations. In strong wind environments, large-span components are significantly subjected to increased wind force, which may cause severe shaking of the components during lifting, making it difficult to control the positioning accuracy and even leading to crane overturning accidents. Rainstorm will make the ground on the construction site wet and slippery, reduce the adhesion of the crane, and increase the instability of the crane during driving and operation. Heavy fog weather can reduce visibility and affect the visibility of operators, making it difficult for them to accurately determine the position and status of components, increasing the risk of operational errors.
（3） Contradiction between crane performance limitations and operational requirements
Cranes of different types and specifications have fixed performance parameters, including lifting capacity, lifting height, working radius, etc. However, the requirements for lifting large-span components often exceed the performance range of conventional cranes. For example, in some large-span bridge construction projects, it is necessary to lift the components to a height of tens or even hundreds of meters, while requiring the crane to be able to operate within a larger working radius range to meet the installation requirements of the bridge structure. However, the lifting height and working radius of ordinary cranes are limited, making it difficult to meet such requirements. Even for some large cranes, once the lifting height and working radius reach a certain value, their lifting capacity will decrease significantly, which cannot meet the weight requirements of large-span components.
In addition, with the continuous development of bridge construction technology, the requirements for the size and weight of large-span components are also constantly increasing, while the technological updates of cranes are relatively lagging behind, leading to increasingly prominent contradictions between the two. In order to meet the requirements of lifting large-span components, it is often necessary to use multiple cranes to work together, but this brings new problems, such as difficulty in ensuring synchronization and coordination between multiple cranes, which can easily lead to uneven force distribution among each crane, thereby affecting the safety and quality of lifting operations.
（4） Difficulties in precision control and stability
Ensuring precise positioning of large-span components during hoisting is a highly challenging task. The installation accuracy of bridge structures requires extremely high precision, and any small deviation may affect the overall structural performance and service life of the bridge. For example, when lifting a steel box girder into place, its axis deviation, elevation deviation, etc. must be controlled within a very small range, otherwise it will cause the connection between the beam segments to be loose, affecting the mechanical performance of the bridge. However, due to various factors such as wind force, inertia force, and crane vibration during the lifting process of large-span components, it becomes very difficult to accurately control the position and posture of the components.
Meanwhile, maintaining the stability of the overall structure is also a key issue in the hoisting process of large-span components. During the lifting process, the components are in a suspended state, which results in poor stability and is susceptible to external disturbances such as shaking and twisting. Once the component loses stability, it not only affects its own lifting and positioning, but may also pose a serious threat to surrounding personnel and equipment. In addition, when multiple large-span components are lifted and connected in sequence, it is necessary to ensure the structural stability of the installed part for each completed component lifting, creating safe conditions for the subsequent component lifting. This requires real-time monitoring and analysis of the stability of the structure during the lifting process, and effective measures to be taken for adjustment and control.
（1） Selection and Application of Advanced Crane Equipment
The selection of crane equipment is crucial in the lifting operation of large-span components. Firstly, it is necessary to accurately analyze the parameters of the components, including weight, size, shape, etc. For example, for a steel box girder weighing 500 tons and measuring 80 meters in length, ordinary small and medium-sized cranes are clearly unable to meet the lifting requirements. At this point, it is necessary to choose a crane with super large lifting capacity and long arm frame, such as a large crawler crane or tower crane. Crawler cranes have the advantages of low grounding pressure, good off-road performance, and the ability to carry loads, making them suitable for construction sites with complex terrain and poor site conditions; Tower cranes have the advantages of high lifting height, large working range, and high operational efficiency, and play an important role in high-altitude lifting operations for large bridge construction.
With the continuous advancement of technology, new types of crane technologies emerge one after another. For example, some cranes adopt advanced hydraulic drive systems. Compared with traditional mechanical drive systems, hydraulic drive systems have the advantages of fast response speed, smooth transmission, and high control accuracy, which can better meet the requirements of crane operation accuracy and stability for large-span component lifting. Some cranes are also equipped with intelligent control systems, which can monitor the working status of the crane in real time, such as lifting capacity, lifting height, working radius and other parameters, and automatically adjust the operating status of the crane based on these parameters, achieving intelligent operation. When the lifting capacity of the crane approaches the rated lifting capacity, the intelligent control system will automatically reduce the lifting speed to ensure the safety of the lifting operation. The application of these new crane technologies has effectively improved the efficiency and safety of lifting large-span components.
（2） Innovative lifting technology and techniques
Innovative lifting techniques and technical methods continue to emerge to address the challenges of hoisting large-span components. The dual or multiple crane lifting process is a commonly used method. When the lifting capacity of a single crane cannot meet the weight requirements of large-span components, two or more cranes can be used to work together. In practical applications, double crane lifting requires precise calculation of the load distribution for each crane to ensure coordinated lifting actions between the two cranes. Taking the lifting of a large bridge steel box girder as an example, through reasonable load distribution and synchronous control, two cranes successfully lifted an 800 ton steel box girder into place.
Segmented lifting technology is also an effective means to solve the problem of lifting large-span components. For some components that are too large in size or heavy in weight, they can be manufactured in sections, then lifted in sections at the construction site, and finally assembled into complete components through welding or bolt connections. This process can reduce the weight and size of each component, making it easier to lift and transport. For example, in the construction of a cross sea bridge, segmented lifting technology was used to divide a 100 meter long steel box girder into several sections for lifting, greatly improving construction efficiency and safety.
The overall lifting technology is to assemble large-span components on the ground and use large-scale lifting equipment to lift them to the design position as a whole. This technology can reduce the amount of high-altitude work, improve construction quality and safety. For example, in the hoisting of steel roof trusses in some large sports venues, the overall lifting technology is used to lift the steel roof trusses weighing thousands of tons from the ground to a height of tens of meters at once, avoiding the tedious process of multiple high-altitude splicing required in traditional hoisting methods and shortening the construction period.
In addition, the application of BIM (Building Information Modeling) technology in the hoisting of large-span components is becoming increasingly widespread. By establishing a three-dimensional BIM model, virtual simulation analysis of the lifting process can be carried out. During the simulation process, potential issues that may arise during the lifting process, such as component collisions and insufficient working radius of the crane, can be identified in advance, and the lifting plan can be adjusted in a timely manner. In a large-scale bridge project, BIM technology was used to simulate and analyze the lifting process of steel box girders, and the problem of collision between components and bridge piers in the original lifting plan was discovered. By adjusting the lifting sequence and crane position, this problem was successfully solved, ensuring the smooth progress of the lifting operation.
（3） Optimization layout and preparation of construction site
The optimized layout and sufficient preparation of the construction site are important guarantees for the smooth operation of large-span component hoisting. In terms of site planning, the walking route of the crane should be reasonably planned based on the model of the crane, the operating radius, and the transportation route of the components. Ensure that the walking route is smooth and solid, avoiding potholes, softness, and other situations to prevent the crane from tilting or sinking during the walking process. At the same time, it is necessary to ensure that the width and turning radius of the walking route meet the traffic requirements of the crane, and avoid affecting the normal operation of the crane due to limited space.
The reasonable setting of the component stacking area is also crucial. The component stacking area should be close to the lifting operation point to reduce the distance of secondary transportation of components and improve construction efficiency. When stacking components, they should be classified and stacked according to their type, specifications, and installation sequence, and effective support and fixing measures should be taken to prevent deformation, collapse, and other situations during the stacking process. For some large and heavy components, specialized foundations should be set up in the stacking area to ensure their stability.
If the ground bearing capacity of the construction site is insufficient, the site needs to be reinforced. Common reinforcement methods include laying steel plates, filling sand and gravel, and setting up pile foundations. At a certain bridge construction site, due to the soft soil foundation on the ground, it was unable to meet the bearing requirements of the crane. The construction personnel used methods such as laying steel plates and filling sand and gravel to reinforce the site, significantly improving the ground bearing capacity and ensuring the safe operation of the crane.
（4） Application of high-precision measurement and monitoring system
The application of high-precision measurement and monitoring systems is crucial for achieving precise positioning of large-span components and ensuring construction safety during the hoisting process. A total station is a commonly used measuring device that can accurately determine the position and orientation of components by measuring angles and distances. During the hoisting process of steel box girder, the total station is used to monitor the axis deviation, elevation deviation and other parameters of the steel box girder in real time. When the deviation exceeds the allowable range, the operation of the crane is adjusted in a timely manner to ensure the precise positioning of the steel box girder.
GPS (Global Positioning System) technology also plays an important role in the hoisting of large-span components. By installing GPS receivers on components and cranes, real-time position information of components and cranes can be obtained, enabling remote monitoring and precise control of the lifting process. In some large-scale bridge construction projects, GPS technology is used to monitor the real-time lifting of bridge components, ensuring that the components can be accurately positioned in different construction environments.
In addition, the real-time monitoring system can provide comprehensive and real-time monitoring of the lifting process. By installing multiple cameras and sensors at the construction site, the images and data during the lifting process are transmitted to the monitoring center. Operators can observe the lifting situation in real time at the monitoring center, detect and handle abnormal situations in a timely manner. For example, when the monitoring system detects that the lifting capacity of the crane exceeds the rated lifting capacity or there is abnormal shaking of the components, it will immediately issue an alarm to remind the operator to take corresponding measures to ensure the safety of the lifting operation.
（5） Personnel training and safety management measures
Personnel are the core factor in the lifting operation of large-span components, and professional training for operators is crucial. The training content should include the operating procedures, lifting technology, safety knowledge, and other aspects of the crane. By combining theoretical learning with practical operation, operators can proficiently master the operation skills of cranes and the process of lifting operations, and improve their ability to respond to emergencies. For example, regular training and assessment of crane operation skills should be organized for operators, and only those who pass the assessment can work on the job, ensuring that operators have solid professional knowledge and skills.
A sound safety management system is an important foundation for ensuring the safety of lifting operations. Establish a sound safety responsibility system, clarify the safety responsibilities of each position, and ensure that every person involved in lifting operations is aware of their responsibilities and obligations in safety work. Develop detailed safety operating procedures, regulate the behavior of operators, and strictly prohibit unauthorized operations. Before lifting operations, conduct a comprehensive inspection of the crane and lifting equipment to ensure good equipment performance and complete and effective safety devices; During the lifting process, clear safety warning signs should be set up, and unrelated personnel are strictly prohibited from entering the lifting operation area.
At the same time, it is essential to develop a comprehensive emergency plan. Develop corresponding emergency response measures for possible crane malfunctions, component falls, personnel injuries, and other unexpected situations, and regularly organize drills. Through drills, operators can become familiar with the process and content of emergency plans, and improve their emergency response and coordination abilities. In the drill, various unexpected situations are simulated to test the feasibility and effectiveness of emergency plans, identify problems in a timely manner and make improvements, ensuring that quick and effective responses can be made in the event of actual emergencies, and minimizing losses to the greatest extent possible.
（1） Case background and engineering overview
Taking a large cross sea bridge project as an example, the bridge is a transportation artery connecting two important economic regions and has important strategic significance for promoting regional economic integration and development. The main bridge of the bridge is a double tower double cable plane steel box girder cable-stayed bridge with a main span of 800 meters. The steel box girder adopts a fully welded structure, with a single section length of 15-20 meters, a width of about 35 meters, a height of about 3 meters, and a weight of 300-500 tons. Due to its location on the sea and complex construction environment, the bridge not only faces harsh natural conditions such as strong winds, waves, and tides, but also has limited working space at sea, which places extremely high demands on the lifting and construction of large-span steel box girders.
（2） Difficulties and Solutions Implementation
In response to the problem of large size and heavy weight of steel box girders, the project team selected two large floating cranes for double machine lifting operations. These two floating cranes both have super large lifting capacity and good stability, with lifting capacities of 800 tons and 600 tons respectively, which can meet the lifting needs of steel box girders. Before lifting, the load distribution ratio of each crane was determined through precise calculation and simulation analysis to ensure even force distribution between the two cranes during the lifting process. At the same time, special design and reinforcement have been carried out on the lifting equipment of the crane to ensure the safety and stability of the steel box girder during the lifting process.
Considering the complex offshore construction environment, the project team has carefully planned and prepared the construction site. A specialized work platform has been built at sea as a temporary storage and transportation site for steel box girders. The homework platform adopts a steel structure with sufficient bearing capacity and stability to withstand the impact of waves and tides. At the same time, a detailed survey was conducted on the surrounding environment of the work platform, obstacles that may affect the lifting operation were removed, and clear warning signs were set up. In terms of the positioning of the floating crane, advanced positioning systems and anchoring equipment are used to ensure that the crane can be accurately positioned and maintained stable during the lifting process.
In order to achieve precise positioning of the steel box girder, the project team utilized a high-precision measurement and monitoring system. Multiple measurement control points were installed on the steel box girder, and the position and attitude changes of the steel box girder were monitored in real time using a total station and GPS. During the lifting process, adjust the operation of the crane in real-time based on measurement data to ensure that the axis deviation and elevation deviation of the steel box girder are controlled within a very small range. At the same time, a real-time monitoring system has been established to provide comprehensive and real-time monitoring of the lifting process, promptly identifying and addressing potential issues. For example, when the monitoring system detects slight shaking of the steel box girder during lifting, the operator adjusts the lifting speed and angle of the crane to quickly restore stability to the steel box girder.
In terms of personnel training and safety management, the project team provided strict professional training to all personnel involved in lifting operations. The training content includes operating procedures for cranes, offshore lifting techniques, safety knowledge, and emergency plans. By combining theoretical learning with practical operation, operators have become proficient in the skills and processes of lifting operations, improving their ability to respond to unexpected situations. At the same time, a comprehensive safety management system has been established, clarifying the safety responsibilities of each position, and detailed safety operating procedures have been formulated to strictly prohibit unauthorized operations. At the lifting operation site, specialized safety management personnel are set up to supervise and inspect the implementation of safety measures, ensuring the safe progress of lifting operations.
（3） Summary of Implementation Effectiveness and Experience
By adopting the above series of solutions, the lifting operation of the steel box girder of the cross sea bridge has achieved complete success. All steel box girders are accurately positioned, with axis deviation controlled within 5 millimeters and elevation deviation controlled within 10 millimeters, far below the allowable deviation range required by the design. The efficiency of lifting operations has also been significantly improved. The original plan was to lift 1-2 steel box girders per day, but in reality, an average of 3-4 steel box girders were lifted per day, greatly shortening the construction period. Throughout the entire lifting process, no safety accidents occurred, ensuring the safety of construction personnel and the smooth progress of the project.
From this case, the following successful experiences and lessons can be summarized: in the construction of large-span component hoisting, advanced equipment selection and innovative hoisting technology are the key to solving construction difficulties. Based on the characteristics of the components and the construction environment, selecting suitable crane equipment and adopting reasonable lifting techniques can effectively improve the efficiency and safety of lifting operations. The application of high-precision measurement and monitoring systems is crucial for achieving precise positioning of components and ensuring construction safety. By monitoring the position and status of components in real-time and adjusting construction operations in a timely manner, construction quality and safety can be ensured. Personnel training and safety management are indispensable links in the construction process. Only by improving the professional quality and safety awareness of construction personnel, establishing a sound safety management system, can safety accidents be effectively prevented and the smooth progress of the project be guaranteed.
Looking ahead to the future, the lifting technology of large-span components in bridge construction will move towards intelligence and automation, demonstrating a broader development prospect.
In terms of intelligent lifting technology, artificial intelligence and machine learning algorithms will be deeply integrated into the control system of cranes. Cranes can automatically identify different construction scenarios and component characteristics by learning and analyzing a large amount of historical data, and then autonomously plan the best lifting path and operation plan. When encountering complex construction site environments, cranes can perceive obstacles and terrain changes in real-time, automatically adjust lifting strategies, and avoid collision accidents. At the same time, the intelligent monitoring system will more accurately monitor and analyze various parameters during the lifting process in real time, such as the stress and deformation of components, the status of key components of the crane, etc. Once an abnormal situation is detected, the system can immediately issue a warning and provide corresponding solutions to achieve comprehensive intelligent control of lifting operations.
Automated lifting technology will also make significant progress. Automated cranes will be able to complete the lifting of large-span components without human operation. Through preset programs and instructions, the crane can automatically complete a series of actions such as lifting, transporting, and positioning components, greatly reducing the impact of human factors on lifting operations and improving the accuracy and stability of construction. In some large-scale bridge construction projects, automated lifting production lines may be used to achieve full process automation from prefabrication, transportation to lifting and positioning of components, further improving construction efficiency and shortening the construction period.
Virtual reality (VR) and augmented reality (AR) technologies will also play an important role in the lifting of large-span components. Construction personnel can conduct lifting simulation training in a virtual environment through VR technology, familiarize themselves with the lifting process and operation points in advance, and improve their operational skills and ability to respond to emergencies. In actual lifting operations, AR technology can overlay virtual construction information onto the real scene, providing real-time guidance and assistance to construction personnel, such as displaying the lifting position, angle, and operating parameters of the crane, helping them to complete lifting operations more accurately.
In addition, with the continuous progress of materials science, new lightweight and high-strength materials will be applied in the manufacturing of large-span components. These materials can not only reduce the weight of the components and lower the requirements for the lifting capacity of the crane, but also improve the performance and durability of the components. For example, bridge components made of carbon fiber composite materials have the advantages of light weight, high strength, and corrosion resistance, which will bring new opportunities and challenges for the hoisting of large-span components.
In the future, the development of large-span component hoisting technology will also focus on integration and innovation with other related fields. The deep integration with Building Information Modeling (BIM) technology will achieve information sharing and collaborative management between the lifting process and the entire bridge construction project, further improving the management level and construction efficiency of the project. The combination with new energy technologies, such as using electric or hybrid cranes, will reduce energy consumption and carbon emissions during lifting operations, achieving green construction.
The importance of hoisting large-span components as a key link in bridge construction is self-evident. In the process of bridge construction, the hoisting of large-span components faces challenges from various aspects such as the characteristics of the components themselves, construction environment, crane performance, and precision control and stability. These difficulties not only test the intelligence and ability of engineering and technical personnel, but also pose potential threats to the safety, quality, and progress of the project.
However, by selecting advanced crane equipment, innovating lifting processes and technical means, optimizing construction site layout, using high-precision measurement and monitoring systems, and strengthening personnel training and safety management, we can effectively overcome these difficulties and ensure the smooth progress of large-span component lifting operations. The practical experience of successful cases also fully proves the effectiveness and feasibility of these solutions, providing valuable reference for future bridge construction projects.
Looking ahead to the future, with the continuous advancement and innovation of technology, the hoisting technology of large-span components in bridge construction will usher in a broader development space. Intelligent and automated lifting technologies will gradually become mainstream, driving the bridge construction industry to new heights with higher precision, efficiency, and safety. At the same time, the integration and innovation with other related fields will also bring new opportunities and breakthroughs for the lifting technology of large-span components, help the continuous development of bridge construction, and make greater contributions to building a more complete and efficient transportation network.
