Untitled Document

An ITD Under-Bridge Inspection Truck scopes out Slate Creek Bridge last July on ID-75.

Sandblaster innovation aids
under-bridge inspections

With ITD responsible for 1,830 bridges statewide, it’s safe to say a fair amount of time and a great deal of importance is placed on maintaining these structures. One tool that is often used in bridge repairs is a simple sandblaster.

Sandblasting is the process of using a machine that forces abrasive material against a surface in order to smooth, roughen, shape, or remove contaminants. In essence, sandblasters are a multiuse tool.

“In a lot of work we do, sandblasting helps with surface prep to ensure patches adhere well,” explains ITD State Bridge Inspector Toby Griffin. “The state has multiple large blasters, but those are not always conducive for more intricate prep that is done underneath bridges.”

In those situations, crews often utilize an under bridge inspection truck (UBIT). UBITs, however, have weight and size restrictions which do not allow for the use of a large sandblaster.

District 4 TTO DJ Price works on the bridge crew during the summer. He was discussing the limitation of using large sandblasters and the cost involved in renting a small one, when Griffin mentioned he had made his own machine many years ago. Pictured right is the homemade sandblaster that is more portable and user-friendly for bridge work under structures.

“I had previously made my own sandblaster in the early '90s for personal use,” Griffin explained. “It cost me around $50 to purchase all the necessary materials, and after all these years, the machine is still holding up and working well.”

Not long after that discussion, D.J. borrowed the smaller, more portable, sandblaster for use on some bridge work.

“One of the best things associated with using the device Toby built, is the cost and time saving benefits,” stated Price. “The smaller machines that are available for rent, have very small nozzles that often plug up and prevent us from completing jobs in a timely manner. With the homemade sandblaster, that was not an issue, so the cost/savings benefit is quite high.”

This idea is just one in a list of many great innovations for the department.

“I really love the innovation program because it helps highlight some of the great ideas our colleagues have been proposing and producing throughout the history of ITD,” Griffin said. “I think historically there are a lot of valuable innovations out there that can improve efficiency and solve problems many of us face in our day-to-day activities.”