Given the ongoing efforts of the Bend Velodrome Project (BVP) to build a velodrome track in Bend, the project’s feasibility has our attention. Cost will be a huge consideration for some critical decisions BVP faces. One of the many factors they’ll have to consider is the material for the track structure as well as whether or not to house it in or outdoors.
Bike Around Bend tracked down Larry Williams, the civil engineer who was in charge of construction for the 1984 Olympic velodrome, and asked his perspective. That outdoor velodrome, on the campus of California State University at Dominguez Hills, was used for two decades before it was demolished in 2003, and replaced by the indoor Home Depot Center Velodrome.
— from CSU Dominguez Hills website.
Prior to construction, Williams said his chief concern was materials selection. He toured several tracks before formulating his final recommendation. His critique of other facilities where wood was used for the track was that not only would it have to be kept wet, because the arid southern California climate risked shrinking it, but it would also have to be elevated to prevent common problems such as rot.
Working on the construction drawings, Williams soon learned the difference between a training track and a track for international competitions: the pitch of the banked turns. He hired an expert in concrete to supervise consistency of the cement. If the “slump” were not stiff enough, the cemented banks wouldn’t hold.
His cement consultant also had a special pouring track built to help screed the cement, as Williams wanted the job done in one pour. One pour would mean no radial joints for a smoother ride. Even with the special measures to get the best pour with just the right mix of concrete, another contractor was hired to grind the concrete surface down to its final race-grade surface.
Williams’ experience in Dominguez Hills may or may not be transferable to Bend, given our freeze-thaw cycles and temperature swings. Concrete, as many Central Oregonians know all too well, is susceptible to spalling which can, if not managed, make a track unsafe.
Even with the weather caveats, Williams still felt that concrete was a superior material to wood given his guesstimates on long term maintenance costs. He emphasized though that a concrete Bend velodrome would likely need to be indoors if not at least covered to stand the best chance of minimizing costly upkeep. And there lies a key trade-off BVP’s Board of Directors will likely weigh: the upfront costs of construction balanced against the ongoing costs of maintenance.