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Prefabricated Bridge

Many decisions are made when it comes to new bridge construction, one of those is the choice of a prefabricated bridge or built on-site construction. How do you know which one works best for your project? Here’s a guide to help you understand prefabricated bridges and when to use them.

What are Prefabricated Bridges?

Prefabricated bridges are built in a separate location, then transported to the construction site for installation. They are a popular form of accelerated bridge construction with their own benefits and considerations.

With U.S. Bridge, our Bridge Kits are a solution for the time-constrained and budget-focused bridge construction projects. We engineer, design, manufacture, and galvanize every piece of the bridge. After each part is ready, we send it to the construction site along with a dedicated member of the U.S. Bridge team to oversee the construction.

Why Use a Prefabricated Bridge?

The first benefit of prefabricated bridges is their quick assembly rate. Unlike building on-site, prefabricated bridges are essentially already made just in separate pieces that are later connected on site. Another advantage is that they are less susceptible to weather delays due to their short assembly time, which decreases the disruption to traffic.

Moreover, prefabricated construction is more energy-efficient and environmentally sustainable in comparison to building on site. As construction takes place within a factory, extra materials are recycled in-house for the next project.

Despite popular belief, modular construction is more affordable and allows flexibility to construction teams. The financial savings not only stem from a shorter construction time but it is also due to the discounts prefabricated construction receives from bulk orders.

In addition, as each component of the bridge is built in a controlled environment, our team ensures the quality of the materials. Furthermore, in-door construction provides a safer setting by decreasing workers’ exposure to open traffic.

When to Use Prefabricated Bridges

The flexibility of prefabricated bridges allows them to be used in various situations. Accelerated construction requires fewer trucks of equipment and materials which is beneficial for remote locations or uneven topography. For instance, prefabricated bridges are often used in emergency situations due to the ease of assembling and disassembling them.

Additionally, prefabricated bridges will benefit your project if your team doesn’t have much experience in bridge construction, as U.S. Bridge sends a member of our team to oversee the construction.

Shorter Construction Time

Due to its accelerated assembly rate, prefabricated bridges are ideal for projects that require temporary construction or projects that are concerned with traffic delays. This is especially the case with U.S. Bridge, as our team can ensure the bridge is built correctly from the start.

If on-site construction time needs to be shorter, then a prefabricated bridge is the best choice. Because of assistance from U.S. Bridge, the bridge construction can be much more efficient and smooth.

Materials for Prefabricated Bridges

Steel and concrete are perhaps the most popular form of prefabricated bridges. The material and the environment of the bridge dictates the design of the bridge. Other components of your bridge project will determine if prefabricated bridges are right for you.

U.S. Bridge: Experts in Prefabricated Bridge Construction

With over 80 years in the bridge construction industry, we’ve engineered and built over 10,000 bridges worldwide. Prefabricated bridge constructions make up a good portion of those constructions. Here at U.S. Bridge, we are dedicated to our customers and the construction of their bridges.

All of our prefabricated Bridge Kits are custom-designed, come with our hands-on expertise in bridge construction, and are built to fit your bridge project needs and budget. Contact us today and let’s talk about how we can make your bridge project a long-lasting success.

Galvanizing Steel

Galvanizing steel is the process of submerging steel in a bath of molten zinc which creates a protective layer that prevents future corrosion. Rust is potentially dangerous and can cause metal parts to become stiff and weaken the integrity of the metal and thus the structure.

Repairing deteriorated steel bridges after decades of use is time-consuming, expensive, and difficult to keep up with.

Hot-dip galvanization for steel not only protects metals from corrosion but also improves maintenance-free longevity. Thus, in the long run, businesses are saving money by keeping their steel galvanized and protected. In addition, the galvanization process is environmentally-friendly and resistant to conditions.

Galvanizing Steel: Three Main Steps

Step 1: Surface Preparation

The first and most crucial step is preparing the surface of the material for the coating process. Zinc will not react to unclean metal, so a successful surface prep is a must. Preparing the steel begins by removing all the dirt, grease, and other contaminants from the metal surface. This method is completed by degreasing the metal in a hot alkali solution or other acidic baths.

Pickling

Then the steel material is pickled through a diluted acidic solution for the removal of mill scales and any rust buildup. Depending on the company, this process is either replaced with or accompanied by abrasive cleanings, such as air blasting sand or metallic shot.

Fluxing

The final process for surface prep is fluxing. This procedure eliminates oxides while simultaneously creating a protective coating for the prevention of the formation of any additional oxides.

Step 2: Galvanizing Steel

After the surface of the metal has been prepped, it’s submerged in a large bath of 98% pure molten zinc at 830° F. The zinc reacts to the clean metal and generates a protective layer.

When the steel has reached the same temperature as the zinc bath, it is then withdrawn, drained, and cooled off before moving to the final step. Depending on the size and thickness of the material, this process could take up to 10 minutes or less.

Post-Treatment

It’s possible that a post-treatment coating will be applied to the metal. This process is called quenching. The steel is dipped in mostly water and some chemicals to create a protective layer. Frequently, finishing steps will include grinding off zinc drips for a smooth finish.

Step 3: Inspection

During the inspection phase, the coating thickness, weight, and appearance is meticulously analyzed and compared against the ASTM Standards. There are two different procedures that can be performed to measure the coating’s level of thickness: magnetic gauges or optical microscopy. Magnetic thickness gauge is the most simple and non-destructive thus making it the most popular method.

Analyzing Coating Weight

The second element that is analyzed is the material’s coating weight. The coating weight refers to the volume of zinc coating on the metal surface. Like the coating thickness inspection process, coating weight has two different methods for measuring the weight. Both the weigh-galvanize-weigh and the weigh-strip-weigh procedure should only be applied to single specimen inspection. These methods have their pros and cons so it’s important to choose the procedure that works best for you.

Final Galvanizing Steel Step

The last component that is inspected is the steel’s appearance and coating finish. All sections of the material are inspected to ensure that it meets the proper standards. As mentioned before, zinc will not react to unclean metal. Thus, the steel’s appearance and finish provides useful information such as revealing any errors that occurred during the galvanization process.

U.S. Bridge is a Certified Steel Fabricator

U.S. Bridge has been serving communities for more than 80 years, building steel bridges that withstand time. We’re a steel fabricator by the AISC for Certified Bridge Fabrication — Advanced (Major) and continue to be a leader in the American steel industry.

Still unsure if galvanizing steel is the right step for your bridge construction? Check our other blogs on the galvanization process and construction services for more information. Contact us today and let’s talk about how we can make your bridge project a long-lasting success.

Benefits Of ABC

Bridge construction is essential to continue rapidly improving America’s infrastructure. With innovative building techniques and effective procedures, there are constantly new cost-effective ways to increase efficiency. That’s where the benefits of accelerated bridge construction (ABC) come into play.

Accelerated bridge construction is a complete shift in how bridges are planned by fully preparing materials to be installed at the bridge site. There are several benefits of accelerated bridge construction over traditional bridge construction — above all are safety, quality, social costs, and the environmental impact.

That’s why U.S. Bridge offers Bridge Kits as a solution for a quick construction time with the same high-quality durability our bridges are known for. Below, we explain the benefits of accelerated bridge construction and why it might be right for your next bridge project. Overall, these benefits reduce bridge construction costs by shortening project time.

Most Significant Benefits of Accelerated Bridge Construction

Here are some of the benefits of accelerated bridge construction:

  1. Shortened bridge project delivery time
  2. Reduce construction impact on traffic
  3. Increase work-zone safety
  4. Prefabricated components require less maintenance
  5. Lower environmental impact

#1: Shortened bridge project delivery time

This is why it’s called accelerated bridge construction — it’s faster than traditional methods. However, it’s equally if not more effective than traditional building.

With precise construction management, prefabricating the bridge parts, and shipping all the parts to the job site, bridge construction time is reduced significantly. With proper planning, bridge parts can be easily installed on-site. This saves time and money throughout the process by completing the project as quickly as possible.

#2: Reduce construction impact on traffic

Highway and other roadway work zones are hazardous for both motorists and for workers. However, as the condition of America’s infrastructure continues to decline, there continues to be long closures to critical roads across the nation. Moreover, this causes delays for everyday drivers, emergency vehicles, and local businesses can suffer from altered nearby traffic patterns.

Ultimately, traffic is unavoidable for Americans, but it can be made slightly better with ABC. With faster construction times thanks to prefabricated parts, construction can move from start to finish in a more timely manner.

#3: Increase work-zone safety

With extended road and lane closures comes increased risk for traffic accidents involving motorists and workers. Each year, there are 2,000 fatal accidents in work zones. With prefabricated parts and a plan to easily construct the bridge, there is less time spent with changes in traffic patterns. Additionally, it’s beneficial for workers on site.

“Now we’re also seeing safety benefits,” Bala Sivakumar, resident ABC expert at HNTB, said to ConstructionDive.com. “It’s a lot safer to do an ABC project because [workers] are not next to traffic or 50 to 100 feet above ground tying rebar or trying to pour concrete.”

#4: Prefabricated components require less maintenance

Prefabricated bridge components are engineered and manufactured specifically for Bridge Kits — our ABC solution. Thus, these parts go through a thorough quality control process to ensure they are ready for on-site construction. While on-site work is held to a high-standard, prefabrication is done in a controlled environment and removed from environmental elements.

With ABC and a thoroughly managed process, we can build bridges that last even longer than traditional building styles.

#5: Lower environmental impact

Another plus to shorter construction time is the significantly reduced impact on the environment. With less time with heavy equipment on-site, the impact to the surrounding environment is significantly reduced. As a result, building accelerated bridge construction lends itself to environmentally-sensitive areas.

Let’s Piece it Together

U.S. Bridge proudly delivers on long-lasting bridge construction projects around the world. We regard every detail of your bridge with a high level of attention and efficiency to ensure it’s high-quality.

With our Bridge Kits, we make bridge installation easy for teams who have the labor and equipment but need manufacturing and engineering. Now, we’re delivering everything needed for bridge construction right to job sites globally.

If you’d like to know more about our Bridge Kits and accelerated bridge construction, please contact us today for a free quote.