ASTM A709 Steel Plate for Bridges: High-Strength, Low-Alloy Structural Steel

ASTM A709 Overview

ASTM A709 steel plate is a high-strength, low-alloy structural steel specifically developed for bridge construction and other load-bearing structures. It offers excellent toughness, weldability, and durability in demanding environments.
The ASTM A709 range covers multiple grades such as Grade 50, Grade 50W weathering steel, and HPS 70W high-performance steel, each designed to meet different bridge engineering requirements.

CJM supplies ASTM A709 bridge steel plates in multiple thicknesses and dimensions, available in hot-rolled, normalized, and TMCP delivery conditions.

Available Grades of ASTM A709 Steel

• ASTM A709 Grade 36
• ASTM A709 Grade 50
• ASTM A709 Grade 50W
• ASTM A709 Grade HPS 50W
• ASTM A709 Grade HPS 70W

A709 Grade HPS 70W offers the best balance of strength and fracture resistance, while A709-50W weathering steel forms a self-protective oxide layer, minimizing maintenance on exposed bridges.

CJM supplies both standard and A709 heavy steel plate up to 200 mm thick, suitable for large-span bridges and heavy-load structures.

ASTM A709 Steel Plate Dimensions and Delivery Conditions

Specification	Range
Thickness	6 mm – 200 mm
Width	1500 mm – 3200 mm
Length	6000 mm – 18000 mm
Delivery Condition	Hot Rolled, Normalized, TMCP
Standard	ASTM A709 / ASME SA709

Our A709 heavy steel plate is suitable for critical structural components such as bridge girders, gusset plates, and tower segments.

Mechanical Properties of ASTM A709

Grade	Yield Strength (MPa)	Tensile Strength (MPa)	Elongation (%)	Charpy Impact
A709 Gr. 36	≥ 250	400–550	≥ 20	Optional
A709 Gr. 50	≥ 345	485–620	≥ 21	Optional
A709 Gr. 50W	≥ 345	485–620	≥ 21	Improved CVN
HPS 50W	≥ 345	485–620	≥ 21	-23°C
HPS 70W	≥ 485	585–760	≥ 18	-23°C

Chemical Composition (% by weight)

Grade	C	Mn	Si	P (max)	S (max)	Cu	Cr	Ni
A709 Gr. 50	≤0.23	0.85–1.35	≤0.40	0.035	0.045	—	—	—
A709 Gr. 50W	≤0.19	0.85–1.35	0.15–0.50	0.035	0.045	0.25–0.40	0.40–0.65	≤0.40
HPS 50W	≤0.11	1.20–1.60	0.15–0.50	0.020	0.010	0.25–0.40	0.40–0.70	0.40–0.75
HPS 70W	≤0.14	1.35–1.65	0.15–0.50	0.020	0.010	0.25–0.40	0.40–0.70	0.40–0.75

Applications of ASTM A709 Bridge Steel Plate

ASTM A709 bridge steel plates are widely used in:

• Highway and railway bridges
• Pedestrian overpasses
• Heavy-load structural supports
• Marine and coastal bridge components (using A709 Grade 50W weathering steel)

Explore our full range of bridge steel plates for different load conditions and corrosion environments.

Processing and Supply Capabilities

• CJM provides cutting, beveling, drilling, and surface preparation for all bridge plate grades.
• For urgent bridge projects, we maintain stock of A709 heavy steel plates and offer fast delivery to global markets, including Southeast Asia, the Middle East, Europe, and the Americas.

Why Choose CJM as Your A709 Steel Plate Supplier

CJM is a trusted bridge steel plate supplier in China, offering:

• Complete grade coverage from Grade 36 to HPS 70W
• Large stock inventory up to 200 mm thick
• Customized cutting and logistics solutions
• Decades of export experience to Europe, Southeast Asia, Africa, and the Americas
• Technical support for project-specific bridge steel requirements

Packaging & Shipping for Bridge Steel Plate & Coil

• Plates: Wrapped with protective layers to avoid surface damage
• Coils: Strapped and covered with waterproof, corrosion-resistant film
• Features: Reinforced pallets · Moisture-proof wrapping · Custom packaging on request
• Logistics: Fast global delivery with reliable shipping partners
• Service: Shipping schedule and cost provided upon inquiry

Contact Us

Looking for reliable A709 Gr.50, HPS 50W, or HPS 70W steel plates for your next bridge project?

WhatsApp: +8618191906640
Email: info@cjmstainlesssteel.com

Frequently Asked Questions

• Q1: What’s the difference between A709 Gr.50 and HPS 50W?
  A709 Gr.50 is a standard carbon steel bridge plate, while HPS 50W adds weathering resistance and is optimized for long-term performance with fewer maintenance cycles.
• Q2: Can A709 steel plates be used in marine environments?
  Yes—especially HPS 50W and HPS 70W grades, which provide strong corrosion resistance in coastal or high-humidity areas.
• Q3: What is the meaning of “HPS” in A709 steel?
  HPS stands for High-Performance Steel—a class of steels that meet stringent requirements for weldability, toughness, and weathering properties.
• Q4: Is ASTM A709 the same as corten steel?
  Not exactly—only A709 Grade 50W and HPS 70W exhibit similar weathering behavior to corten steel.
• Q5: Is ASTM A709 equivalent to AASHTO M270?
  Yes, ASTM A709 and AASHTO M270 share the same chemical and mechanical requirements, differing mainly in certification format.

You may also be interested in our weathering steel plate category for broader corrosion-resistant applications.

Q: What is your company’s main products/services?

A: We are a professional manufacturer for Carbon Steel, Alloy Steel and Profile products. We have the experience of steel business for more than 10 years and our products are exported to Mid East,South America,Southeast Asia,Africa,South and East Asia etc.

Q: Can I go to your factory for a visit?

A: Of course, we welcome customers from all over the world to visit our factory.

Q: What are your terms of payment?

A: 30% T/T deposite and 70% balance before shipment.

Q: What is your delivery time?

A: For stocks,we could transport the goods to loading port within 7 days after we received the deposit; For production,it usually takes about 15-30 days after receiving the deposit.

Q: Do you provide samples? Are they free or paid?

A: Samples are available for free,but the courier freight will be covered by customer account.

Q: Do you accept the third party inspection?

A:Yes, we fully accept ‌third-party inspections.

Q: Why should I buy from you not from other suppliers?

A: Integrating the superior resources of China’s steel industry, we provide customers with high-quality steel products at preferential prices, and can ensure that the goods are delivered to customers in a timely manner.

Q:How can you guarantee quality?

A: Always a pre-production sample before mass production;Always 100% inspected before shipment