Steel plate availability is often a critical factor in determining both the timeline and budget for bridge construction. When contractors are aware of current steel availability, they can more accurately estimate lead times and avoid delays.

Start your research with NSBA's plate availability page, where you'll find several tables showing maximum plate length availability for a variety of widths, thicknesses, and grades of steel from up to three domestic mills.

Find out more about using these tables--and get an overview of the plate sizes commonly produced by domestic mills--when you read "Steel Plate Availability for Highway Bridges," published in Modern Steel Construction.

Once you're aware of the availability of plate sizes, it's time to contact a mill. Using AISC's shape search tool, input the shape, weight, and grades you're looking for, and you'll find out which mills produce the shapes you're looking for.

Looking for a place to start? AASHTO G12.1-2020 Guidelines to Design for Constructability and Fabrication Section 1.4 discusses the most readily available plate lengths for various thicknesses and widths.

NSBA's Accelerated Steel: Achieving Speed in Steel Bridge Fabrication provides critical insights that directly benefit contractors by streamlining the steel fabrication process. It outlines how to coordinate with fabricators, owners, and engineers, ensuring that all aspects of fabrication are aligned with the project schedule and construction goals.

By following the practices outlined in this guide, contractors can ensure more efficient, coordinated, and timely steel fabrication processes, ultimately improving project outcomes and boosting profitability.

Reducing construction time is often a top priority for bridge contractors. The following methods have been proven effective in speeding up steel bridge projects:

• Design/build (progressive D/B) contracts encourage faster decision-making and flexibility.
• Bridge prefabrication reduces time spent onsite by assembling large sections off-site.
• Incremental launching allows for continuous bridge construction, reducing the need for extensive temporary support structures.
• Using steel/elastomer deck panels speeds up deck installation by eliminating the need for traditional cast-in-place decks.

Find out more about each of these strategies for speeding up steel bridge construction with NSBA's document, Reducing Time for Steel Bridge Construction.

Corrosion protection is essential to the longevity and durability of steel bridges. By choosing the right corrosion protection system during the pre-construction phase, bridge contractors can enhance project efficiency, reduce delays, and ensure optimal resource utilization throughout the construction process.

One cost-effective solution is uncoated weathering steel (UWS). UWS has inherent corrosion protection and doesn't require any coating applications, so the steel is ready for erection much faster than coated members. This shaves time off the construction schedule, and even long after construction, it minimizes traffic disruptions due to decreased maintenance needs. Download the Uncoated Weathering Steel Reference Guide to learn about site and location considerations, design recommendations, structural design, detailing, and maintenance for this system.

Another system to consider is single-coat inorganic zinc (SIOZ). Inorganic zinc coatings (such as paints) are frequently used as a primer layer in paint systems for steel structures. Used alone, SIOZ can provide appropriate and cost-effective corrosion protection in some situations. Learn more about this system in NSBA's report, Single Coat Inorganic Zinc Protection for Steel Bridges.

Introducing conceptual solutions during the early phases of bid preparation can help identify innovative approaches that reduce costs or construction time. Collaborating with designers and engineers to explore different construction methods or materials can lead to more competitive bids.

No need to reinvent the wheel! NSBA has a collection of 88 solutions for three-span bridge superstructures that can help you kick off your bid. The Continuous Span Standards can streamline the estimating process, allowing you to propose cost-effective, proven solutions that align with industry standards.

Skewed and curved bridges present unique challenges in terms of fitting steel girders. Keeping these complexities in consideration during the bid phase is critical to ensuring proper alignment and avoiding unforeseen cost increases during construction. Read the Skewed and Curved Steel I-Girder Fit Summary for more information and recommended fit conditions.

It's important to understand the relationship between material quantities and costs in order to prepare a competitive bid. NSBA's Span to Weight Charts provide critical data on the relationship between span lengths and the weight of steel required, which directly impacts material costs. Utilizing Span to Weight Charts ensures that you are accurately estimating quantities of material needed, leading to more precise cost projections.

Collaboration between bridge contractors, designers, and engineers during the design phase helps ensure that all parties are aligned on project specifications, budget, and timelines.

Getting contractors involved early in the design phase allows them to provide practical insights on constructibility and identify potential challenges before they arise on-site. Contractors can identify design elements that could lead to cost overruns or delays and provide alternatives that are more efficient or cost-effective.

Find our recommendations for designing straight bridges with little or no skew in the NSBA guide, Navigating Routine Steel Bridge Design. This streamlined design guide features a series of hyperlinked checklists that walk engineers and designers step-by-step through the process, focusing on the specific provisions of the AASHTO Specifications that apply to routine bridges.

Value engineering plays a key role in optimizing the design of a bridge project without compromising quality. This approach allows contractors to collaborate with designers on alternative construction methods, material selections, and streamlined processes to enhance the overall value--and maintain the structural integrity and performance--of the project.

Value engineering in bridge type/solutions

A main feature of the I-91 Interchange 29 exit ramp flyover bridge, the three-I girder steel bent cap reduced fabrication and shipping costs while providing load path redundancy. This solution shows how thoughtful design and engineering can lead to cost savings during construction as well as long-term savings in reduced fracture-critical inspections.

Press-brake-formed tub girders (PBFTGs) are another example of value engineering in bridge design. This system is a lightweight, cost-effective solution that minimizes fabrication time and reduces the overall project cost while offering a longer service life than other systems used for short- and medium-span bridges.

Link slabs can be used to eliminate expansion joints, leading to a more cost-effective and low-maintenance design. Learn more about link slabs and other common forms of prefabrication in the recorded webinar, Benefits of Steel in Accelerated Bridge Construction.

Bolting methods

The thoughtful use of technology like TNA bolts, DTI washers, and optimized splice configurations can reduce labor time while improving the integrity of connections.

Optimize your bolted connections with NSBA Splice. This tool takes the time-consuming task of designing and checking a bolted splice connection and rewrites the process with a simple input page and output form. NSBA Splice can be incorporated as a design tool on plate girder bridges allowing the designer to quickly analyze various bolted splice connections to determine the most efficient bolt quantity and configuration.

Lean-on bracing

Cross-frames are one of the costliest elements in a steel bridge on a per-pound basis. Reducing the number and complexity of cross-frames can have a significant impact on the speed of fabrication, speed of erection, and overall bridge cost. Lean-on bracing represents a way to potentially eliminate at least 50% of the full cross-frames required for a routine steel I-girder bridge without adding any cost to the girders.

Corrosion protection systems

Selecting the right corrosion protection system is essential for ensuring the longevity of steel bridges. The right strategy can extend the bridge’s lifespan while minimizing future maintenance costs.

By leveraging collaborative design practices, value engineering, and advanced corrosion protection strategies, contractors can ensure the bridge is designed for both constructibility and long-term durability.

An easy and attractive way to speed up steel bridge construction while reducing long-term costs and environmental impacts is uncoated weathering steel (UWS). UWS allows steel to naturally develop a protective oxide layer, minimizing long-term maintenance needs. NSBA's Uncoated Weathering Steel Reference Guide is your one-stop shop for everything you need to know about designing with this system. Need to find out more before you commit? View the latest research on UWS performance in the Federal Highway Administration's Weathering Steel Performance Data Collection.

Find out more about durability strategies for steel bridges by watching a recorded session from Modern Corrosion Protection Systems, a webinar hosted by the Short Span Steel Bridge Alliance (SSSBA), NSBA, and the University of Wyoming. 

Project mobilization is the first crucial step in the construction phase. It involves the organized deployment of resources, equipment, and personnel to the construction site to ensure a seamless transition from planning to execution.

• Make a plan for mobilizing resources and personnel: A detailed mobilization plan includes determining the optimal location for equipment, arranging workforce schedules, and ensuring that all materials are ordered and delivered on time to prevent delays.
• Optimize the setup of on-side facilities: On-site facilities must be strategically located to streamline operations, with areas dedicated to material storage, crew accommodations, and equipment staging.
• Consider material handling: The proper handling of construction materials is vital to maintain their integrity and prevent damage. For instance, proper bolt storage will help ensure the longevity of bolts long after construction is completed. For detailed guidance, check out this article on structural bolting issues.

The use of advanced construction methods can significantly reduce construction time, improve efficiency, and minimize risks associated with bridge projects.

• Accelerated Bridge Construction (ABC): ABC methods allow contractors to reduce onsite construction time, which minimizes the impact on traffic and improves overall safety. Techniques such as prefabricated bridge elements, self-propelled modular transporters (SPMTs), and longitudinal launching have revolutionized the way bridges are built. For a comprehensive guide, refer to the FHWA ABC Manual. Consider ABC methods like slide-in bridge construction.
• Prefabricated Bridge Elements and Systems (PBES): Prefabricated components assembled offsite save time and reduce onsite labor. These systems are key to minimizing the project duration and ensuring quality control.
• Structural Placement Methods: Depending on the site and project scope, contractors may use advanced techniques such as SPMTs, longitudinal launching, or even conventional heavy lifting equipment to place large bridge elements efficiently. Learn more with a case study on steel girder launching.

Ensuring that the project is designed for efficient construction is crucial for avoiding delays and keeping costs in check.

For example, proper planning for crane access and the erection sequence can greatly reduce onsite issues. Contractors must account for terrain, crane size, and other logistical challenges to ensure that large components can be safely erected without impacting the overall project timeline. Learn more from the bridge erection perspective.

Efficient scheduling is key to minimizing delays and ensuring that the project stays within its timeline and budget. Successful project schedule management involves anticipating potential obstacles and planning contingencies to maintain momentum.

• Techniques for Effective Project Scheduling: Utilize advanced scheduling tools and techniques to break the project into manageable milestones, ensuring that each phase is completed on time and aligns with the overall project goals.
• Strategies for Minimizing Delays: Identify potential risks early, including weather, material shortages, and labor availability, and incorporate buffer time where necessary to keep the project on track. For further guidance, refer to NSBA's Reducing Time for Steel Bridge Construction.