I recently traveled to Northern California, and I had a very busy week. Between the sales calls and some project work, I took some time to visit and inspect Sacramento's Tower Bridge, a bridge I refer to quite often in my presentations. Here's why I'm so interested in Tower Bridge:
- In 2008, Tower Bridge became the first bridge with a Fiber Reinforced Polymer (FRP) cantilever sidewalk, and it was installed by one of the original FRP bridge deck suppliers.
- The vertical lift bridge first opened for traffic in 1935.
- Tower Bridge was added to the National Register of Historic Places in 1982.
Back to my inspection. As I walked across the bridge, I looked closely at the wear surface. It's a polymer concrete material with small size aggregate. To the average pedestrian it looks like any other concrete surface. I spotted some reflective cracking in the polymer concrete over the panel-to-panel joints. This is because most overlays do not have enough elongation to span the gap between panels during cold temperatures. However, this wear is no worse than what you would typically see on other concrete bridges.
The timing of my visit was perfect. As I continued across the sidewalk, the bridge’s lift span was raised to allow a large boat to pass. I got a good look at the FRP panels on the structure’s steel supports and was able to take some photos. The panels looked fine.
It’s always helpful to see projects like this in the field because bridge engineers and owners frequently ask me how bridges similar to their projects are doing.
One of the main reasons for my trip was to discuss our FiberSPAN cantilever sidewalk product with a number of Bay Area design firms. It’s important to continue educating engineers and design firms about FRP, its advantages, ease of use and extended life cycle. It was also helpful to be able to share “real time” observations with decision makers about a bridge and sidewalk system that is right in their own backyard.
If you have any questions about the Tower Bridge inspection or FRP cantilever sidewalks, get in touch.