AASHTO M180 is the American specification for corrugated sheet steel beam used in highway guardrail systems. SinoBarrier rolls and hot-dip galvanizes our W-beam and thrie-beam sections to M180, and issues a factory test report with every shipment so your tender documents, material submittals and site acceptance checks are backed by paper, not promises.
What AASHTO M180 actually covers
M180 governs the beam itself — the rolled, galvanized sheet-steel section — not the post, the bolt or the terminal. It sets three groups of requirements you will be asked to verify at tender:
- Base metal: the steel grade, thickness and mechanical properties the section is rolled from.
- Geometry: the corrugated profile, depth, width, hole pattern and bolt-slot layout that let one manufacturer’s beam mate with another’s posts and terminals.
- Zinc coating: the hot-dip galvanizing weight per square metre, the minimum coating thickness, and adhesion.
The parameters we control in-house
Because we roll, punch and galvanize on the same floor, we commit to the numbers below rather than quoting the spec from a catalogue.
| Parameter | SinoBarrier value | Reference |
|---|---|---|
| Coating weight (both faces) | 550 g/m² minimum | AASHTO M180, Type / Class per project |
| Base metal | Q235B or S355JR, per drawing | mill certificate issued |
| Section profile | W-beam (double-wave) & thrie-beam (three-wave) | rolled in-house |
| Standard length | 3810 mm / 4130 mm (custom on request) | cut to order |
| Hole & slot pattern | slotted bolt holes for thermal movement | punched to drawing |
How to get our test report
Every M180 order ships with a coating-weight report, a base-metal mill certificate and a packing list. For tenders that need them up front, send the item number, quantity and destination port and we return the certificate pack with your quotation — typically within one working day.
How to cite M180 in your tender document
When you write the specification, referencing the standard by number plus your coating class is enough to make the requirement enforceable. Example wording:
“Guardrail beam shall be hot-dip galvanized corrugated sheet steel conforming to AASHTO M180, with a minimum coating weight of 550 g/m², supplied with a mill test certificate and a coating-weight test report.”
If your project follows a state supplement — Caltrans guardrail details, FHWA acceptance guidance, or a local DOT addendum — send us the clause and we will confirm conformance against the same base metal and coating numbers, because M180 is the common denominator they all build on.
M180 is the beam. These are the tests that sit alongside it.
- MASH TL3 / TL4 — full-scale crash testing of the assembled barrier system, the standard that verifies the beam actually redirects a vehicle.
- EN 1317 / CE — the European equivalent for projects supplied into the EU, with CE documentation.
Together they cover what a procurement team checks before award: the material is right (M180), the system performs (MASH), and the paperwork is complete.
Questions buyers ask about M180
Is AASHTO M180 the same as a “galvanized guardrail”?
Not exactly. “Galvanized” describes the coating; M180 is the full specification that includes the coating, the base metal and the section geometry. A beam can be galvanized without being M180-compliant, so always reference the standard by number.
What coating weight should I specify?
550 g/m² is the common export default for highway exposure; coastal or high-humidity sites sometimes call for heavier classes. We produce to whatever class your tender names.
Can you supply the certificate before I place the order?
Yes. We issue a sample certificate pack with the quotation so your compliance review is not blocked waiting for a purchase order.