As an integrated industrial and trade foreign trade company specializing in steel structure bridge export, EVERCROSS BRIDGE TECHNOLOGY (SHANGHAI) CO., LTD. boasts strong OEM production capabilities, committed to manufacturing high-quality steel box girder bridges that fully meet customer requirements and various international bridge design standards. With advanced production equipment, a professional technical team and strict quality control system, we have successfully delivered numerous steel box girder bridge projects to overseas markets, winning wide recognition from customers around the world. Let’s elaborate on what a steel box girder bridge is, its advantages, application scope, how our OEM production ensures compliance with international standards, and take the Taizhou Yuhuan Xuanmen Bay Steel Box Girder Bridge as an example to demonstrate our strength, concluding with common customer questions and answers.

1. What is a Steel Box Girder Bridge?

A steel box girder bridge, also known as a steel box beam bridge, is a type of bridge where the main beam is composed of steel plates welded or bolted into a hollow box-shaped cross-section. This closed box structure integrates the top plate, bottom plate, web plates, and internal stiffeners, forming a complete load-bearing system that can effectively bear and transmit various loads such as vehicle loads, pedestrian loads, wind loads, and seismic loads. Compared with traditional beam bridges, the steel box girder bridge has unique structural advantages, making it widely used in various large-span and complex bridge projects around the world. Its structural design can be flexibly adjusted according to the actual needs of the project, which is highly compatible with OEM production and can fully meet the personalized needs of overseas customers.

2. Advantages and Application Scope of Steel Box Girder Bridges

2.1 Core Advantages

Steel box girder bridges have significant advantages in structural performance, construction efficiency and economic benefits, which are the key reasons for their wide application in export projects. Firstly, they have excellent mechanical properties: the closed box cross-section provides high bending stiffness and torsional stiffness, which can effectively reduce structural deformation and ensure the stability and safety of the bridge even under large-span conditions. Secondly, they are lightweight and high-strength: compared with concrete box girder bridges, steel box girders have lighter self-weight under the same load-bearing capacity, which can reduce the design load of bridge piers and foundations, thereby reducing the overall project cost. Thirdly, the construction efficiency is high: steel box girders can be prefabricated in the factory through standardized production, and then transported to the construction site for assembly, which greatly shortens the on-site construction period and reduces the impact on the surrounding environment and traffic. In addition, steel box girder bridges have good durability and maintainability; through scientific anti-corrosion treatment, their service life can reach more than 100 years, and later maintenance is convenient and low-cost.

2.2 Application Scope

Due to their outstanding performance, steel box girder bridges are widely used in various scenarios, especially suitable for export projects with diverse geographical and environmental conditions. They are mainly used in the following fields: large-span highway and railway bridges, including cross-river, cross-sea and cross-valley bridges; urban viaducts and interchange bridges, which can effectively save urban space and improve traffic efficiency; industrial zone bridges and port wharf bridges, which can adapt to the harsh working environment of industrial areas and ports; and landscape bridges in tourist areas, where the flexible structural design can be combined with the surrounding environment to achieve both functionality and aesthetics. For example, the Taizhou Yuhuan Xuanmen Bay Steel Box Girder Bridge, which we participated in, is a typical application of steel box girder bridges in cross-bay scenarios, fully demonstrating its adaptability to complex marine environments.

3. International Bridge Design Standards for Steel Box Girder Bridges

As an export-oriented enterprise, EVERCROSS strictly abides by various international bridge design standards to ensure that our steel box girder bridges meet the technical requirements of different countries and regions. The following table lists the main international bridge design standards we follow, including their scope of application and core requirements:

4. OEM Production of Steel Box Girder Bridges by EVERCROSS: Taking Taizhou Yuhuan Xuanmen Bay Project as an Example

EVERCROSS has rich experience in OEM production of steel box girder bridges. We can customize production according to customers' specific requirements, including bridge span, load level, structural size and anti-corrosion standards, while ensuring full compliance with the corresponding international design standards. The Taizhou Yuhuan Xuanmen Bay Steel Box Girder Bridge is a typical case of our OEM production capability combined with international standard compliance.

The Taizhou Yuhuan Xuanmen Bay Steel Box Girder Bridge is a single-pylon semi-floating cable-stayed bridge with a main span of (120+75)m, and its main beam adopts a steel-concrete composite steel box girder structure with a total width of 39m. The project requires the steel box girder to have high torsional stiffness and corrosion resistance to adapt to the high-salinity marine environment of Xuanmen Bay, and needs to meet the Chinese national standard GB 50017-2017 and relevant international standards. As an OEM manufacturer, we undertook the production task of the steel box girder for this project, and achieved the following key points in the production process to ensure compliance with standards and customer requirements:

Firstly, in the design stage, our technical team conducted in-depth communication with the customer and the design unit, thoroughly understood the design intent and technical requirements, and combined the relevant provisions of GB 50017-2017 and international standards to optimize the structural design of the steel box girder. We used BIM technology to build a 3D model for simulation analysis, ensuring that the structural strength, stiffness and stability of the steel box girder fully meet the design requirements and can adapt to the marine environment and seismic conditions of the project site.

Secondly, in the material selection stage, we strictly selected high-quality steel materials that meet the standard requirements, and conducted strict inspection on the incoming materials, including chemical composition analysis, mechanical performance testing and other items, to ensure that the material performance meets the design standards and customer requirements. For the anti-corrosion treatment of the steel box girder, we adopted a multi-layer anti-corrosion coating system suitable for marine environments, including epoxy zinc-rich primer, high-build epoxy intermediate coat and fluorocarbon topcoat, which effectively improves the corrosion resistance of the steel box girder and ensures its 100-year service life.

Thirdly, in the production process, we adopted advanced numerical control cutting, welding and assembly equipment, and implemented standardized OEM production processes. The steel plates were pretreated by shot blasting to reach Sa2.5 level, and then cut and formed by numerical control equipment to ensure the accuracy of component size. The welding process adopted automatic submerged arc welding and CO₂ gas shielded welding, and the welding quality was strictly controlled in accordance with international standards, with 100% non-destructive testing (ultrasonic testing and magnetic particle testing) carried out on the welds, ensuring that the weld qualification rate reached 100%. At the same time, we set up 12 key quality control points throughout the production process to ensure that each link meets the standard requirements.

Finally, in the inspection and delivery stage, we conducted a comprehensive inspection of the finished steel box girder, including dimensional accuracy, welding quality, anti-corrosion performance and other items, and issued a quality inspection report in accordance with international standards, ensuring that the product fully meets the customer's requirements and the relevant international design standards before delivery. The successful completion of the Taizhou Yuhuan Xuanmen Bay Steel Box Girder Bridge project fully demonstrates EVERCROSS's strong OEM production capability and strict compliance with international standards, laying a solid foundation for our steel box girder bridge export business.

5. Common Customer Questions and Answers

In the process of exporting steel box girder bridges, we often receive various questions from customers. The following are the most common questions and our professional answers, helping customers better understand our OEM production capabilities and product quality:

Q1: Can EVERCROSS customize steel box girder bridges according to our specific project requirements, and how to ensure that the products meet the design standards of our country?

A1: Yes, we have professional OEM customization capabilities. We can customize the span, load level, structural size, anti-corrosion standard and other parameters of the steel box girder bridge according to your specific project requirements. Before production, our technical team will conduct in-depth communication with you to confirm the relevant design standards of your country (such as AASHTO LRFD, Eurocode 3, etc.), and integrate these standards into the product design and production process. We will also provide you with detailed design drawings and technical documents for confirmation, and conduct strict quality inspection in accordance with the corresponding standards during the production process to ensure that the final product fully meets your requirements and the design standards of your country.

Q2: What anti-corrosion measures does EVERCROSS take for steel box girder bridges exported to marine environments, and how long is the anti-corrosion service life?

A2: For steel box girder bridges exported to marine environments, we adopt a multi-layer professional anti-corrosion system, including shot blasting derusting (reaching Sa2.5 level), epoxy zinc-rich primer, high-build epoxy intermediate coat and fluorocarbon topcoat, which can effectively resist the corrosion of seawater, salt fog and other harmful substances. For extreme marine environments, we can also provide thermal sprayed aluminum (TSA) or zinc-aluminum coating according to customer requirements. Under normal maintenance conditions, the anti-corrosion service life of our steel box girder bridges can reach more than 50 years, and the overall service life of the bridge can reach more than 100 years, which fully meets the durability requirements of marine environment projects.

Q3: How long is the production cycle of OEM steel box girder bridges, and what logistics solutions do you provide for export?

A3: The production cycle of OEM steel box girder bridges depends on the size, quantity and complexity of the project, generally ranging from 3 to 6 months. We will formulate a reasonable production plan according to your project schedule to ensure on-time delivery. For export logistics, we have established long-term cooperative relations with professional international logistics companies, which can provide sea, land and air logistics solutions according to your needs. We will also handle the relevant export procedures (such as export license, commodity inspection, customs declaration, etc.) for you in accordance with the 2026 steel product export policy, ensuring that the products are safely and smoothly delivered to your designated destination.

Q4: Does EVERCROSS provide technical support and after-sales service for exported steel box girder bridges?

A4: Yes, we provide full-process technical support and perfect after-sales service for exported steel box girder bridges. During the design and production stage, our technical team will communicate with you in a timely manner to solve any technical problems encountered. After the product is delivered, we will send professional technical personnel to the site to guide the installation and commissioning of the steel box girder if you need it. In addition, we provide a long-term after-sales service guarantee. If there are any quality problems during the use of the product, we will respond in a timely manner and send personnel to handle it, ensuring the normal operation of the bridge.

With strong OEM production capabilities, strict quality control system and rich international project experience, EVERCROSS BRIDGE TECHNOLOGY (SHANGHAI) CO., LTD. is committed to providing high-quality, standard-compliant steel box girder bridges for global customers. We will continue to adhere to the concept of "quality first, customer foremost", continuously optimize production processes, improve product quality, and become your trusted partner in steel structure bridge export business.