The word platform hides a real design choice. A steel weighbridge deck is a fabricated assembly that arrives on site as a finished, tested component; a concrete deck is civil work that becomes a scale when it cures and is fitted with load cells. Neither is universally right. The decision turns on how the structure resists torsion, how its surface is protected, how quickly it can be installed and how the buyer intends to maintain it. This note compares them on figures we can document, and stays away from claims that belong in a brochure rather than a specification.
Two different ways to carry the load
Our steel decks use a U-section profile welded into a fully closed cavity. The closed box is the point: it gives the module high torsional stiffness, so a load applied near one edge, or by a vehicle stopping slightly off-centre, does not twist the deck and bias the cells. There are no open channels where water, grit or spillage can collect, which matters on quarry and bulk-material sites where wash-down is routine and debris is always present.
A cast-in-place concrete deck carries load through its mass and reinforcement. It is heavy and stiff once cured, and continuous with the foundation, so the boundary between scale and civil work is blurred. That continuity is a genuine advantage on sites that want the weighing surface to read as part of the slab. It also means the weighing performance depends on site workmanship, cure conditions and reinforcement placement, variables a factory does not control.
For a distributor importing equipment, the practical difference is where the quality is verified. A steel module is built and inspected before it ships; a concrete deck is built on the client's ground, to the client's schedule, with the client's materials.
Fatigue, joints and what testing actually proves
A weighbridge is a high-cycle asset. Every truck crossing flexes the structure a little, and the failure mode to design against is fatigue at welds and joints rather than a single dramatic overload. Our U-section deck has passed a 2,000,000-cycle third-party fatigue test. That figure is not a lifespan promise; it is evidence that the welded detail survives repeated loading in a controlled test, and it is the kind of number a buyer can ask any supplier to put in writing.
Joints are the other fatigue hotspot. In a multi-module ZDG-type assembly, the connection between platforms has to transfer load without becoming a hinge. Fully welded closed-cavity modules keep the joint count low and the joint geometry stiff, and the module boundaries can be set to fall between axle groups. Concrete decks are usually continuous, which removes the mechanical joint but introduces construction joints and the cracking that follows shrinkage and thermal movement.
Both structures need properly specified load cells under them. Our cells are rated for 150% overload, and the load cell and sensor data page describes the instrumentation that sits beneath either deck type. The deck and the cells should be specified as one system, not chosen separately, because stiffness, mount geometry and cable routing are shared decisions.
'Heavy duty' means nothing on a drawing; a documented fatigue cycle count, a stated section profile and a measurable coating thickness do. If a supplier cannot name them, the comparison is being made on marketing rather than engineering.
Surface preparation and corrosion protection
Steel corrodes, so a steel deck is only as good as its coating system. Ours is blasted to Sa2.5 before painting, then given a double-sided, double-layer coating with a dry film of at least 120 um. Blasting grade, number of layers and dry film thickness are three numbers that can be checked on delivery with a gauge, which is why we print them instead of saying anti-rust paint. The closed cavity also means the inside of the box is protected before the module leaves the line, where a brush cannot reach afterwards.
Concrete does not rust, but it is not maintenance-free. It can absorb water and salts, spall at joints and wear at the surface under steel tyres and chains, and repairs usually mean closing the lane for a cure period. Its protection is the quality of the mix, the cover over reinforcement and the cure, all of which are site-controlled and hard to verify once the pour is done.
On a coastal port or a mine with aggressive runoff, the comparison becomes a maintenance question: a factory-applied, measurable coating system on a stiff steel box, versus a porous slab whose condition depends on local workmanship. Our how it is built page documents the steel route line by line, including the weld sequence and the coating steps, so a buyer can see exactly what is being specified.
| Parameter | Fully welded U-steel deck | Cast-in-place concrete deck |
|---|---|---|
| Where quality is verified | Factory, before shipment | On site, during construction |
| Torsional behaviour | Closed U-section box, high stiffness | Continuous reinforced slab |
| Fatigue evidence | 2,000,000-cycle third-party test | Depends on reinforcement detail and cure |
| Surface protection | Sa2.5 blast, double-layer coating, dry film >= 120 um | Mix design, cover and cure |
| Joint count | Low; ZDG modules joined as one stiff deck | Few mechanical joints, construction joints present |
| Installation dependency | Set on prepared piers or into a pit | Formwork, pour and cure on site |
| Programme control | ~60 day fabrication window from confirmed drawing | Governed by site schedule and weather |
Installation footprint and programme
A steel module ships as a finished assembly. On a pitless site it can be set on prepared piers with shallow approaches; on a pit site it drops into a completed pit. Our own engineering, manufacturing, installation and maintenance teams stay on the project from drawing to commissioning, and lead time is around 60 days from a confirmed drawing with a minimum order of 1 unit. That programme is predictable because most of the work happens before the machine leaves Yantai, Shandong, China, not during a short possession window on a live site.
A concrete deck needs formwork, reinforcement, a pour and a cure period before load cells can be fitted and the scale calibrated. The schedule is therefore governed by weather, site access and local concrete supply. None of that is a defect, but it is a different kind of project risk.
Trade terms matter here too. Because we quote EXW, FCA, FOB, CNF, CIF, DAP or DDP, a distributor can decide how much of the civil and installation scope to take locally. The installation and service page outlines what our team covers when it is engaged, and the price guide lists the scope items that move a quotation.
Choosing by site, not by slogan
For a permanent, high-cycle site where a documented factory test and a measurable coating matter, the fully welded U-section steel deck is the straightforward choice, especially when the buyer wants a short, predictable installation window. For a site where the deck is being poured as part of a larger slab and the client has strong local civil capability, a concrete deck can be a reasonable civil solution with weighing instrumentation fitted to it. Neither answer survives being applied to every project.
Be wary of comparisons that declare a winner without naming the site. Soil condition, water table, traffic mix, available possession time and local maintenance skill all shift the answer. The honest specification states the capacity class, the deck dimensions and module count, the construction and coating figures, the load cell configuration and the foundation type, then lets the buyer weigh them against their own constraints.
If you are comparing offers, put the two decks side by side against the same specification table and the difference stops being a matter of opinion.
Send the site conditions, the traffic mix and the capacity you need to our engineering desk through the contact page. We will return a documented specification for the steel build, with the fatigue, coating and dimension figures stated, so the comparison is made on numbers.