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Advantages, Designs, and Uses of Precast Box Culverts

By November 21, 2016 No Comments
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Legos look like blocks for creating linear towers and buildings. Who knew you could design aircraft carriers, the Taj Mahal, or even a car with these hollow plastic pieces?  The versatility of legos may not seem immediately apparent, but the possibilities they present are limited only by the builder’s imagination. Precast box culverts are similar. The hollow, rectangular four-sided concrete structures appear to have a few straightforward uses, such as creating a drainage tunnel or a bridge. They are a versatile and ideal addition to any project.

What Is a Culvert?

Precast concrete box culverts are an alternative to circular concrete pipes. Box culverts drain high volumes of water and can generally handle a higher flow rate than pipes. Precast box culverts offer superior strength and easier installation when compared to systems such as long-span metal arches and multi-barrel circular drains. While commonly used for drainage, a box culvert can be used as a tunnel, for storage or in material handling.

Some culverts double as bridges that can accommodate vehicular and pedestrian traffic. Other culverts are relatively small. Box culverts are shaped as you’d imagine: like a box. However, Columbia Precast Products can make culverts in various shapes and sizes. We’ll manufacture a custom box culvert to suit your project.

Precast Box Culvert Designs

Precast box culverts are available in several sizes and configurations. Standard box sizes can be from three feet wide and two feet tall all the way up to a 12-by-12 foot square. Typically, precast box culverts are sold in six and eight-foot lengths. At Columbia Precast Products, our precast box culvert sizes range from a six-foot span by three foot rise to 12 foot rise. Columbia Precast Products can create custom sizes to meet precise project specifications.

Other customizable features include:

  • Joints: Your precast box sections have tongue and groove points to allow for mastic joint compound packing, as well as packing with pre-formed mastic or butyl gaskets or even mortar.

  • Linings & Coatings: Depending on your project, a wide variety of linings and coatings exist for your use.

  • Three-sided bridge: Three-sided bridge units offer structural integrity while allowing for a natural stream bed. Environmentally-friendly, these bridges can be installed with zero impact on the waterway and ecosystem.

  • Headwalls: Used at the inlet and outlet of a pipe system, headwalls are mainly intended for use with box culverts, but may also provide an outlet for a larger stormwater system.

  • Precast footings: Stored and installed in sunny or rainy weather and with minimal work, these footings can be simply dropped into a hole and built upon from there.

Code requirements will also affect precast box culvert designs. In Washington state, for example, precast box culvert designs used for bridges must meet specifications for concrete strength, connections or footings, and reinforcement. Just as multiple Legos are used for plastic structures, multiple cells of precast box culverts can be used for more complex designs such as stream crossings or highway underpasses.

What Are the Advantages of Precast Box Culverts?

Some culverts are made by pouring concrete at the site, but precast concrete products offer several advantages. Here are a few of the benefits of precast box culverts:

Strength: We design culverts to meet or exceed required load capacity. Precast concrete can be manufactured to safely support pedestrians, livestock, automobiles, rail transportation and more.

Uniformity: Precast concrete allows for strict control during manufacturing. The quality of poured-in-place concrete can suffer with variations in weather. Problems with temperature, curing and craftsmanship are more common when workers must contend with the wet, cool temperatures in Washington and Oregon.

Fewer delays: Precast concrete culverts can be manufactured well in advance. When it’s time to install, the culvert requires a crane and a small work crew. Backfill around the structure as soon as it’s installed. Once in place, other construction can begin. This ease of installation reduces budget-busting delays.

Let it rain: The rainy weather typical in Vancouver and Portland often delays construction. When manufacturing precast products, precipitation and temperature are never a factor. Precast concrete can be installed during wet conditions and cold temperatures.

Budget and eco-friendly: Installation of precast box culverts require fewer workers and hours which can ultimately save money. Our products are safe for the environment. We use recycled materials when possible and efficient processes that conserve water. Concrete is a natural material. As a company, we strive to improve our methods to ensure minimal environmental impact.

Variety of Uses for Box Culverts

We know precast box culverts make strong bridges, supporting the weight of cars, trucks, or trains. And you’ve likely seen precast box culverts used for short-span tunnels and drainage systems. Other applications you may not have considered include the following:

  • Creating waterway passages. A precast box culvert can remove obstructions below the water, restoring habitats for fish and other water-dwelling species.
  • Carving out urban trails. A multi-cell design can provide safe passage under highways and greenways for pedestrians and cyclists.
  • Providing underground access. Law enforcement agencies in high-density urban settings have used precast box culverts to create an underground path from station to jail, avoiding the use of public streets. Box culverts have also supported construction expansion projects, by providing a way to move materials under a street instead of over. Precast box culverts are also appearing in rural areas, helping cattle farmers shift stock from field to farm without disrupting traffic.
  • Managing rainwater runoff. Multi-cell precast box culvert storage areas can collect rainwater runoff overload and hold it until local water treatment facilities can manage the excess and flow it back into the system.
  • Simulating military environments. Precast box culverts have been used to replicate Afghanistan’s cave environment for military training exercises.
  • Building industrial passages. The exceptional strength of precast box culverts makes them especially useful as ducts for electrical cables, hot water, oil, steam, or air.

Box culverts provide a solution when you face depth or height restrictions or when you need wide, shallow passageways. Their versatility makes them a go-to choice for challenging installations. The lower cost of labor and simpler installation process involved with box culverts delivers better value than metal. Precast box culverts are shipped to location – no pouring in the field – for faster, high-quality builds.

Industry Leaders in Precast Concrete

If you’re ready to use precast concrete box culverts in your next projects, have questions about box culverts, or are curious about what else precast concrete can be used for, contact Columbia Precast Products today.