How Climate Change Can Impact Bridges

Climate change has had unforeseen consequences on the safety and functioning of infrastructure. Some studies have shown that bridges have turned out to be especially vulnerable to the effects of climate change due to its link to the extreme heat and increased flooding involved. Every part of bridge engineering is being threatened by the shifts in our environment down to the very materials that are needed for construction. Bridges serve as vital links in our transportation system, and it is imperative that the engineering and maintenance of bridges receive immediate attention.

Weather Events and Their Effect on Bridges

When bridges are built, the engineers intend on them lasting for decades, if not centuries. However, climate change has caused conditions that were not anticipated at the time of construction. The lifespan of bridges is likely dramatically affected from the rapid shifting in our environment. Even existing design codes are being tested by the significant changes. Only now are we building bridges with the much-needed adjustments in engineering and construction.

Climate change has impacted the frequency and intensity of flooding events, and they are one of the most pressing concerns. Fast-moving water erodes the sediment around bridge foundations and threatens their structural integrity. Rising sea levels are only exacerbating the problem as well. Besides flooding, the effects of extreme heat on our bridges are also a huge issue that must be addressed. As with flooding, excessive heat accelerates the disintegration of bridges.  According to a study, extreme temperatures may cause 1 in 4 steel bridges in the United States to collapse by the year 2050. In the meantime, we can eventually expect more widespread bridge repairs needed along with frequent closures, for the sake of everyone’s safety.

Other events such as extreme wind, wildfires, and storms are affecting bridge safety and serviceability too. All these weather events influence the resilience of bridges facing on-road traffic accidents. The increase in the frequency of precipitation as weel as the projected increase in liquid water content of fog lead to lower driver visibility and more slippery pavement. This inevitably leads to more vehicle collisions on our bridges.

Furthermore, landslides are a growing threat in regions that are susceptible to them. For instance, Australia is expected to see increased rainfall and tropical storms in some areas. Landslides are usually triggered by either intense rainfall or human activity and climate change is altering both of these causes. There is an urgent need to forecast how and where landslides might affect Australians in the future. In response, research teams have been studying the true effects of these changes and have created a nationwide map showing the anticipated changes in landslide hazards caused by climate change. Engineers, councils, and residents can use these maps to make valuable assessments of the risks of landslides in their area and how the risk may escalate in the future.

Engineering Challenges

The worsening effects of climate change have called for a design that hones the focus on resilience. For existing bridges, there has been an increase in inspections for fractures on bridges and on the level of erosion due to weather. On top of that, inspectors will be looking for potential future failures and will make for more frequent repairs of bridge decks and replacement of bearings. For new bridges, designs will be concentrating even more on long-lasting quality and functionality.

This includes adjustments in construction planning and structural engineering with materials such as prestressed concrete and precast concrete. Weathering steel will also be typically used now to combat corrosion problems that are linked to class carbon-steel bridges. Changes in engineering and construction are necessary for everyone's safety, and the issues that need to be addressed are clear. This is just another of many ways we will have to adapt to the dramatic shifts in our climate.