The stretch of Montrose Avenue just west of Cumberland Avenue in Chicago sees heavy traffic daily as thousands of vehicles stream past on their way to O’Hare Airport and Interstate 294. Lane closures cause acute pain for everyone involved. So when 60 feet of utility lines running under the roadway needed repair this spring, excavator RW Collins Co. knew time wasn’t on their side.

“We’re part of the team that handles emergency excavation throughout the city,” says Tom Cook, sales and estimating manager for Collins. “The challenge here was to remove wet, sandy fill surrounding the lines, backfill and reopen the street in the shortest time possible.”

Cook had heard about Redi-Fill from Prairie Material – the fast-setting, flowable fill used by cities and utilities across the region for quick road repairs. He contacted Dan Drake, territory manager for Prairie, who confirmed this would be the perfect opportunity for Collins to give Redi-Fill a try.

Self-leveling mix cuts safety risks

With more than 65 years in the excavation business, Collins makes crew safety a top priority. Backfilling with the usual sand-and-aggregate mix means “putting people down a hole with compacting equipment, which always opens the door for accidents,” says Cook. “Redi-Fill flows right into the void from the truck and self-levels, so we’re eliminating those risks.”

The Montrose Avenue job started with a 55-foot-by-60-foot cut in the road surface, followed by vacuum excavation to safely remove soil around several utility lines. Crews used Redi-Fill to support the utilities after getting the old fill out.

Working in 10-foot sections, the team handled line soil removal and pumped Redi-Fill into the 8-foot depths, running a static roller over the surface after placement to test stability.

‘Wow! Just like we saw in the video’

“We were amazed at how this mix performed – just the way we saw it in the online video,” Cook says. “It didn’t sink and the surface stayed tight. The next day we’d be excavating right up to the Redi-Fill placed the day before with total confidence.”

Prairie’s Des Plaines plant delivered more than 500 yards of Redi-Fill over the course of the project. The client realized real cost savings, Cook says – and motorists smiled when the road reopened in about half the time it would have taken using traditional backfill materials.

Great for more than just road repairs

Now that his team has tested it, Cook sees Redi-Fill as an ideal material for other jobs as well.

“We work at a good number of sites near buildings with shallow foundations or slab-on-grade, where you don’t want vibration so close to the foundation,” he explains. “Redi-Fill is perfect since you can fill the entire void and come back the next day, knowing you’re set to go for site restoration work.”​