Limited culverts nationwide are made of which material?

• A. Metal
• B. Concrete
• C. Plastic
• D. Wood

Answer: (A)

The material choice for limited culverts is driven by balancing strength, installability, and cost for small to mid-span crossings. Metal culverts, typically steel or aluminum, offer a strong enough structure for limited loads while remaining lightweight and easy to transport and install. They can be manufactured in standard corrugated shapes that fit many site conditions, and with galvanizing or coatings they resist corrosion well enough for many road drainage applications. For limited or temporary installations, the quicker fabrication and field installation of metal culverts often make them more cost-effective than pouring reinforced concrete on site. Concrete culverts, while extremely durable, require heavy equipment, formwork, and longer construction time; plastic culverts are light and corrosion-resistant but may not handle heavier loads or long-term durability in all situations; wood has a shorter service life. All this tends to make metal the most common choice for limited culverts nationwide.