Much of the country’s bridge inventory was built in the decades after World War II, and many structures are nearing the end of their intended service life. As owners with budget concerns debate repair strategies versus replacement plans, the components that let a bridge move, shed water and carry load are getting more attention. Expansion joints and bearings are among the hardest-working parts of any structure, and often among the first to need repaired or replaced.

Ben Jacobus has watched those components perform. As national sales manager for bridge products at the D.S. Brown Company, Jacobus has spent more than 27 years working with bridge owners, engineering consultants, contractors and transportation professionals across the country on construction, rehabilitation and maintenance projects. Based in Minnesota, he has experience with structural bearing assemblies, expansion joint systems and waterproofing solutions, and he takes a customer-focused approach to matching products to the specific demands of each job. He represents a company with 135 years in the business, whose products appear on 55 of the projects on ARTBA’s list of “250 Transportation Projects That Helped Build America,” including the Golden Gate Bridge.

In this exchange with Roads & Bridges, which was conducted over email, Jacobus discusses what it takes to keep components performing on a landmark structure more than 90 years old, and a lesson the industry learned from early strip seal expansion joints. He also explains why so many joint and bearing problems come down to installation and maintenance, and how owners can tell when continued maintenance stops making sense. Finally, he looks ahead to the technologies he expects to reshape bridge work over the next two decades, and the one he believes the industry is least prepared to adopt.

R&B: D.S. Brown products are part of 55 projects on ARTBA’s list of "250 Transportation Projects That Helped Build America," including the Golden Gate Bridge. What does it take to keep components working on a landmark structure like that decades after they’re installed, and what have those long-lived projects taught you about designing for durability?

BJ: The most important factor is selecting the right products for the right application, especially when working with a bridge that is over 90 years old. For example, when performing partial-depth concrete deck repairs, higher compressive strength does not necessarily translate to a longer service life. A product with lower compressive strength but greater resilience and impact resistance may provide better long-term performance. As manufacturers, it is essential to ask the right questions and understand all the relevant variables so companies like D.S. Brown can recommend products and components that provide the most effective, durable, long-term solutions for each application.

R&B: Over 135 years, what’s one lesson D.S. Brown learned the hard way, maybe a product, detail or assumption that didn’t hold up in the field, and how did it change the way the industry designs bridge components today?

BJ: Strip seal expansion joints were introduced in the late 1960’s.  They became the preferred expansion joint solution for short and medium span bridges by the early 1980’s due to its watertight design and ability to handle over 4” of total movement.  The original strip seal design wasn’t as robust as the steel rail shapes used today and in the early stages, paint was the only corrosion inhibitor.  By 1995, hot dip galvanizing became part of the state’s standard specifications, which significantly improved the performance of all carbon steel components used in infrastructure projects.  

R&B: Expansion joints and bearings are often among the first bridge components to need repair or replacement. What do you see going wrong most often on existing bridges, and how much of it comes down to design, installation or maintenance?

BJ: In my opinion, expansion joints and bearings have some of the most challenging responsibilities on a bridge: effectively and safely accommodating movement while maintaining structural performance, durability, and public safety.

I believe many problems with expansion joints and bearings stem from inadequate maintenance and improper installation. Debris and deicing salts can accumulate in expansion joints, restricting movement and accelerating deterioration. While many bridge owners recognize the importance of spring bridge washing and removing debris and deicing salts, this maintenance is not consistently performed every year.

Proper installation is equally important. Even a well-designed product can fail prematurely if it is not installed according to the manufacturer's specifications. My advice is to work closely with manufacturers and never hesitate to ask questions or seek technical guidance. Proper design, installation, and consistent maintenance are all essential to maximizing the service life of these components.
 
R&B: With so much of the country’s infrastructure built in the mid-20th century now reaching the end of its service life, what are owners getting right and wrong as they plan rehabilitation versus replacement?

BJ: This is a difficult question to answer because so many variables must be considered, including design life, budget constraints, traffic impacts, user costs, political pressures, environmental concerns, and safety. What I do know is that, even with newer structures, the key to maximizing service life is performing maintenance early and ahead of schedule. However, there is a point of diminishing returns when an asset approaches the end of its service life, and owners must recognize when continued maintenance is no longer the most practical or cost-effective solution compared to replacement. 
 
R&B: What changes do you expect over the next 10 to 20 years, whether in materials, longer design lives, monitoring technology, or the workforce, and which of them do you think the industry is least prepared for?

BJ: Advancements in AI and 3D modeling will improve design accuracy and reduce design lead times.  Real-time monitoring will help us move beyond annual inspections and make faster, better-informed decisions.  Drones and robots will also play a larger role in inspections and maintenance, especially in dangerous or hard-to-reach areas. While robotics offer clear advancements in safety and efficiency, the industry's slow adoption rate remains a critical vulnerability, particularly for hazardous operations. The infrastructure industry needs to be more proactive in embracing these technologies to protect workers and extend infrastructure service life.