Built for salt air: a 100-ton hot-dip galvanized weighbridge on the coast

Steel and sea air are a bad combination. Salt settles on every surface, humidity keeps it damp, and rust starts wherever paint is thin or chipped: along edges, around welds, inside hollow sections nobody can reach with a brush. For a truck scale on the coast, the platform steelwork takes this punishment every day, on top of the weight of the trucks. This case study looks at how we built a 100-ton weighbridge for a seaside customer around one decision: protecting the whole structure with hot-dip galvanizing instead of relying on paint.

Project at a glance

Client: [China Construction Engineering]

Location: [China]

Equipment: 100-ton hot-dip galvanized truck scale

Platform size: 3 m x 18 m

Foundation:pit-type

Weighing system: 10 load cells-30 t

Commissioned: [05, 2026]

Why the sea changes the specification

Inland, a well-painted weighbridge can last for years with modest upkeep. On the coast, salt-laden air speeds up corrosion, and the pit and platform stay damp for much of the year. A paint system is a thin barrier on the surface. Once it is scratched, chipped, or worn at an edge, moisture reaches bare steel and rust spreads sideways underneath the coating. On a long platform with many welds, corners, and enclosed sections, there are simply too many places for that to begin.

What hot-dip galvanizing actually is

In hot-dip galvanizing, the fabricated steel is cleaned and then immersed in molten zinc. The zinc reacts with the steel and forms a series of zinc-iron alloy layers, topped by a layer of pure zinc. The result is a coating that is bonded to the steel itself, not just sitting on top of it. Coating thickness is governed by standards such as ISO 1461 and depends on the thickness of the steel, and for this project it was [coating thickness / standard applied].

What it does for a coastal weighbridge

Full coverage. Because the whole fabricated structure goes into the zinc bath, the coating reaches inside hollow sections, into corners, and over weld seams. These are exactly the places a brush or spray gun struggles to reach, and exactly where coastal corrosion starts.

Protection that continues after damage. Zinc protects steel in two ways. It acts as a physical barrier, and where the coating is scratched, the surrounding zinc corrodes in preference to the steel, protecting small exposed areas. A truck chain dragged across the deck or a dropped tool is much less of a threat than it would be to a painted surface.

A tough surface. The alloy layers are hard and resist abrasion better than most applied coatings, which matters on a platform that sees steel tires, chains, and dirt every day.

Consistent quality. Galvanizing is done in a controlled workshop process, not in the open on site, so quality does not depend on weather, humidity, or the skill of a painter on the day.

Lower upkeep. A painted structure on the coast needs repainting on a regular cycle, each time with downtime, access work, and surface preparation. A galvanized structure needs inspection and the occasional touch-up, not repeated repainting.

How the scale was built

The platform is 3 m wide and 18 m long, rated for 100 tons. It sits in a shallow pit, which keeps the deck close to road level and simplifies the approaches. Ten load cells of 30 t each support the structure. Their combined rated capacity is far above the 100-ton scale rating, which leaves generous reserve for off-center loading and occasional overload, both of which are common at ports and coastal yards. Spreading the cells along the 18-meter length also helps keep the load distribution stable as long vehicles roll on and off.

As is standard for galvanized fabrications, the steelwork is welded and finished before galvanizing, and the design includes the vent and drain openings the zinc bath requires. Fasteners are galvanized as well, so the bolted connections are protected like the rest of the structure. The load cells are sealed units and are protected as a separate matter, with sealed cable entries and a junction box placed where it stays dry.

A shallow pit near the sea: what to watch

A shallow pit is easier to build and drain than a deep one, but near the coast the ground is often wet and the water table high. Drainage was designed into the foundation, so water leaves the pit instead of sitting around the load cells and the underside of the platform. Galvanizing protects the steel, but good drainage is what protects everything else.

Looking after it

Galvanizing reduces maintenance. It does not remove it. We recommend rinsing the platform with fresh water to remove salt deposits, but without pointing high-pressure jets at the load cells or cable entries. Check the coating periodically, especially along edges and wherever vehicles contact the structure, and repair any damaged spots with a zinc-rich touch-up coating. Keep drains clear, and verify accuracy on a regular schedule, more often than you would inland.

About the supplier

We're Fujian Fangda Weighbridge, a truck scale and load cell manufacturer based in Fujian, China. We build weighbridges and the load cells inside them, including hot-dip galvanized platforms for coastal and humid sites. If you're planning a scale near the sea, tell us your vehicles, site conditions, and layout, and we'll talk through the options.

100-ton Weighbridge & Truck Scale