In overseas road and bridge projects, form travelers and bridge steel formwork are large-scale temporary steel structures. Long-distance ocean shipping, port handling, inland transportation, marine salt-fog corrosion and on-site assembly at remote sites constitute major risk points of the project. This paper elaborates on the modular splitting principles for export, anti-corrosion packaging schemes for export, sea lashing and reinforcement measures, inspection procedures upon arrival at destination ports, on-site modular assembly techniques and acceptance requirements of form travelers and customized steel formwork. Combined with Boyoun Heavy Industry's practical experience in exporting equipment for overseas bridge projects, it sorts out frequent failures of overseas projects and corresponding prevention & control countermeasures, providing technical references for general contractors and construction teams on the export and on-site installation of form travelers and steel formwork.

Pier Formwork

1. Modular Splitting of Formwork

Restricted by container dimensions, lifting capacity at destination ports, and height & width limits of roads in host countries, form travelers, pier column formwork and segmental girder formwork cannot be shipped as integral units. Based on literature research, component splitting shall follow the principles below:

1. Splitting joints shall be preferentially arranged at bolted connections to minimize hot welding work on site;

2. The weight and overall dimensions of individual components shall match container loading limits, and accommodate the lifting capacity of cranes at destination ports;

3. All components shall be assigned unique serial numbers. Reference datum lines and positioning pin holes shall be marked during fabrication to guarantee component interchangeability;

4. Thin steel faceplates and deformable components shall be split separately and not stacked with heavy main trusses of form travelers to avoid extrusion deformation during transportation.

Formwork Export Packaging 

2. Export Packaging and Marine Salt-Fog Protection Technology

The marine transport environment features high salt fog and condensation inside containers caused by temperature fluctuations between day and night, which can easily lead to steel corrosion and coating damage. The following protection measures can be adopted:

1. Pre-treatment before delivery: Components shall be shot-blasted for rust removal and fully coated with primer and topcoat. Precision parts such as bolt threads, pin shafts and bevels of hydraulic pipelines shall receive separate anti-rust treatment;

2. Classification packaging strategy: Pin shafts, high-strength bolts, gaskets, seals and small accessories shall be packed independently in waterproof wooden cases. Form traveler trusses, steel formwork back ribs and faceplates shall be loaded into standard containers or flat rack containers;

3. Anti-collision isolation: Rubber buffer pads shall be installed at contact surfaces of components, and corner protectors fitted at sharp edges to prevent scratches on anti-corrosion coatings caused by jolting during ocean transportation;

4. Moisture control inside containers: Sufficient desiccants shall be placed inside containers. Components shall be fully wrapped with waterproof stretch film and container seams sealed to reduce internal condensation.

3. Key Points for Sea Loading, Lashing and Reinforcement

Vessels experience rolling and pitching during ocean navigation, and component sliding or overturning may cause severe damage.

1. Sleepers shall be laid at the bottom of containers. After components are positioned, steel wire ropes together with turnbuckles shall be applied for rigid lashing to prevent component displacement;

2. Reasonable center-of-gravity arrangement: Heavy components shall be placed in the lower part of containers to avoid offloading risks during lifting and transportation due to eccentric loading;

3. Over-sized heavy components such as main girders of form travelers shall be shipped in flat rack containers. Markings for center of gravity, lifting points and anti-overturn warning shall be sprayed on the outer side of components;

4. Lashing plans shall be checked for sliding and overturning stability under vessel rolling conditions to ensure reliable fixing throughout the ocean voyage.

4. Unloading at Destination Port, Inland Transportation and Re-inspection upon Arrival

Inspection after the equipment arrives at the destination port is a critical procedure prior to on-site assembly.

1. Check the outer packaging and containers for damage or seawater soaking traces before unpacking;

2. Count components item by item against the packing list; inspect components for deformation, coating dents and corrosion;

3. Priority inspection of load-bearing components including main trusses of form travelers and formwork girders: re-measure geometric dimensions and inspect weld appearance. Components with excessive deformation shall be corrected; components with base metal tearing or severe plastic deformation shall not be used for assembly;

4. Flexible cushions shall be kept under components and rain & dust protection implemented during inland transportation from port to construction site.

5. On-site Assembly and Acceptance Key Points

1. Preparation of assembly yard The assembly yard shall be hardened and leveled. Bearing capacity calculation of the yard shall be carried out and special assembly jigs erected to avoid assembly errors induced by uneven foundation settlement.

2. Assembly sequence control Assemble components sequentially from top to bottom in accordance with serial numbers. Assembly sequence for form travelers: bottom basket assembly → main truss installation → transverse bracing system → formwork system assembly. For steel formwork, assemble the frame first, then install faceplates.

3. Construction control of high-strength bolts High-strength bolts shall go through three working procedures: initial tightening, re-tightening and final tightening. Torque values shall strictly comply with design specifications, and complete torque construction records retained. Alignment gaps and misalignment shall be strictly controlled.

4. Acceptance after assembly Re-measure the overall geometric dimensions after full assembly. Form travelers must undergo on-site preloading tests to eliminate non-elastic structural deformation and verify overall stiffness and deflection indicators. Form travelers can only be used for bridge cantilever casting after passing preloading acceptance.

6. Common Risks and Prevention & Control Countermeasures

Overseas projects often face challenges including language barriers, unfamiliarity of local workers with Chinese temporary steel structures and missing spare parts. Boyoun provides supporting guarantee solutions:

1. Bilingual assembly drawings (Chinese & English) and component lists are supplied, with serial numbers engraved on components for easy on-site identification;

2. Spare and wear parts are packed separately, including pin shafts, high-strength bolts, seals, repair coating and other consumables;

3. Boyoun technical personnel conduct on-site technical disclosure and deliver installation & safety training for local construction teams;

4. Random cutting or modification of steel structural components is prohibited on site. Any dimensional deviation must be assessed and handled by professional technicians.

Conclusion

Bumps and salt-fog corrosion during ocean transportation are the main causes of damage to overseas form travelers and bridge steel formwork. Adopting rational modular splitting, professional anti-corrosion packaging, rigid container lashing & reinforcement, together with re-inspection at destination ports, standardized assembly procedures and preloading acceptance can greatly reduce equipment damage rate, minimize rework in overseas projects and mitigate schedule delay risks. Boyoun Heavy Industry can provide modular splitting design, export packaging schemes and container stowage design for form travelers and various bridge steel formwork, together with bilingual drawings and on-site overseas technical support, catering to export demands of temporary steel structural equipment for road and bridge projects worldwide.