On April 17, 2025, the world's largest-span three-tower cable-stayed bridge — the Ma'anshan Yangtze River Highway-Railway Bridge on the Chaohu-Ma'anshan Railway — was officially closed, laying a solid foundation for the early opening of the Chaohu-Ma'anshan Railway. Liu Chengzhou, Executive Deputy General Manager of Liugong OVM, led his team to attend the closure ceremony and celebrate this historic moment together.

As a core participant in the Ma'anshan Yangtze River Highway-Railway Bridge project on the Chaohu-Ma'anshan Railway, Liuzhou OVM Machinery Co., Ltd., with its strong independent innovation capability, safeguarded this mega project and demonstrated the hard strength of China's infrastructure.

Breaking through bottleneck problems Creating the pinnacle of stay cable technology

    As the lead research unit for the "ultra-high-strength, high-fatigue-resistance, durable parallel wire cable system," OVM, under the guidance of the owner and design institutes, jointly developed with upstream and downstream industry partners a 2100 MPa-grade parallel wire cable system with fully independent intellectual property rights. This technology achieved three milestone breakthroughs:

  (1) Developed ultra-high-strength (2100 MPa, 7 mm diameter), high-fatigue-resistance (fatigue stress amplitude 510 MPa), and highly corrosion-resistant zinc-aluminum-magnesium alloy coated steel wire.

  (2) Developed layered multi-stage high-fatigue-resistance anchoring technology, proposed a new bending fatigue test method considering both axial and transverse directions, and for the first time in the industry successfully developed an ultra-high-strength (2100 MPa), high-stress-amplitude (280 MPa) parallel wire cable system, achieving the world's first application of a 2100 MPa ultra-high-strength, 280 MPa ultra-high-stress-amplitude parallel wire cable system.

  (3) Developed new technologies to enhance stay cable durability, including a dual flexible waterproof sealing structure with multi-element alloy co-infiltration corrosion protection for anchors and intelligent monitoring technology, greatly extending cable service life.

Intelligent manufacturing empowers, precision control sets new records

According to monitoring requirements, negative deviation in cable length was not permitted for the Ma'anshan Yangtze River Highway-Railway Bridge, effectively doubling the length precision requirement. To meet the precision requirements, OVM designed a high-precision cable length manufacturing process based on factors affecting cable length.

(1) Developed phased-array total-focus nondestructive testing technology for cable anchors, improving the efficiency of qualitative and quantitative defect detection, achieving high-precision 3D imaging of cable anchoring defects, and reducing misjudgment and missed detection of defects;

(2) Proposed a new wire protection scheme for the cable manufacturing process. By adding protective coatings to tooling during cable manufacturing, damage to steel wire and its coating can be effectively avoided;

(3) Developed a complete set of process control technology using standard wire for precise cable length control in ultra-long stay cables. Negative deviation in stay cable length is not permitted; for cables of 200 meters and below, the positive length deviation is controlled within 0.02 m; for cables above 200 meters, the positive length deviation is controlled within (L/20000+0.01) m, exceeding product standard requirements.

Smart construction sets a new industry benchmark

During the construction phase, multiple innovative OVM processes rewrote engineering records:

1. Dedicated large-scale equipment was deployed to provide strong technical support for the installation and construction of ultra-long, heavy-tonnage stay cables, such as newly designed large-tonnage intelligent jacks, large-tonnage cable unreeling reels, and large winches, ensuring construction safety.

2. PE quality protection during tower-end hanging and girder-end cable deployment. For long cable tower-end hanging, winches inside the tower and pulley blocks outside the tower were used for multi-point lifting to distribute lifting point loads, reducing PE stress at force points and ensuring the safety of the outer PE surface quality of the cables. For girder-end cable deployment, anchor head trolleys and four-wheel deployment trolley pads were used to keep the stay cables from dragging on the ground during deployment, protecting the outer PE quality of the stay cables from damage.

3. Combination of girder-end anchor pressing winch and steel strand soft traction technology. For girder-end anchor pressing construction of long and heavy cables, dedicated clamps were designed, and a construction technology combining large-tonnage winch pulley block traction with multi-strand steel strand soft traction was adopted to ensure construction safety, improve construction efficiency, and guarantee finished product quality.

4. Adoption of a multi-point synchronous intelligent tensioning system. Controlled by a host computer control system, by collecting data from pressure sensors and displacement sensors on jacks and displaying tension force and oil pump operating status in real time on a human-machine interface, intelligent synchronous tensioning of 12 cables was achieved. Programmed automatic control of cable force or elongation value improved cable force synchronization and accuracy and increased work efficiency.

5. Revolutionary breakthrough in incremental launching construction of the auxiliary Han River bridge. For the first time, OVM's "visualized intelligent monitoring system + multi-point self-balancing incremental launching process" was adopted to help successfully and precisely launch the 13,000-ton steel truss girder of the auxiliary branch bridge of the Ma'anshan Yangtze River Highway-Railway Bridge on the Chaohu-Ma'anshan Railway into place.

As a controlling project of the Chaohu-Ma'anshan Intercity Railway, the upper deck of the Ma'anshan Yangtze River Highway-Railway Bridge is a two-way six-lane urban expressway, and the lower deck carries four railway tracks. The main navigable bridge over the left branch of the Yangtze River is designed as a three-tower steel truss cable-stayed bridge with a main span of (2×1120) meters, and it is also the world's first three-tower cable-stayed bridge with a single span exceeding one kilometer. The Chaohu-Ma'anshan Intercity Railway is an important component of the riverside corridor of the national "Eight Vertical and Eight Horizontal" high-speed rail network. It connects to the Hefei-Hangzhou High-Speed Railway in the north and the Nanjing-Anqing High-Speed Railway in the east, and is a direct link between Ma'anshan and Hefei, the capital of Anhui Province. It is expected to open in September 2026, when travel time between Hefei and Ma'anshan will be shortened to 45 minutes.

Up to now, OVM has filed more than 10 national patents for this project, including 5 invention patents. OVM will continue to increase innovation efforts and accelerate its development into a world-class specialized leading enterprise that is "professionally outstanding, innovation-driven, lean in management, and distinctive in characteristics," using innovation to improve project quality, drive China's bridge construction to new heights, and contribute to building China into a transportation powerhouse.