Concrete steps ahead for new bridge
At 7 p.m. Friday, crews will begin to pour 1,000 cubic yards of concrete for the new Grand Avenue bridge deck. For reference, 1,000 cubic yards is approximately 100,000 basketballs.
Crews will start to pour concrete from the abutment north to Seventh Street (near the connection of the steel girders). During this time, approximately 12 concrete trucks per hour will be traveling from facilities in Gypsum, Rifle and Carbondale. Pump trucks will be staged on the east and west sides of Seventh Street to pump the concrete onto the new bridge deck.
Our team anticipates that this concrete pour will span approximately 12 hours. Weather and temperature are extremely important to the schedule and completion of this section. If it is raining or too cold, crews will move the work to Saturday evening.
This concrete pour is part of our critical path schedule to open the Grand Avenue bridge to two lanes of traffic in November. By “critical path” I mean the sequence of activities that must be finished on time for the project to be completed on schedule. The reason we chose Oct. 6 as our concrete pour date is that the 12-hour pouring period spans two rush hours. By pouring Friday night into Saturday morning, concrete trucks will avoid one rush hour period, thus creating efficiencies in this scope of work. If both Friday and Saturday have bad weather or cold conditions, this concrete pour will be rescheduled for Friday, Oct. 13.
In addition to being part of critical path and a huge milestone for the community, we are asking our afternoon northbound commuters to help by reducing traffic Friday. The increase in trucks on the detour route could cause more significant delays than normal, and it is crucial that crews are able to complete this pour to open the new bridge on time. If you do not need to drive north on Colorado 82 during the peak commute time, please avoid the detour route on Friday.
Concrete pours are extremely technical, and Colorado Department of Transportation quality assurance testers will be on site monitoring the pour. Once the concrete is poured, there is a five-day cure time during which testers will be monitoring the concrete’s strength. During this time, the concrete will be covered with blankets to keep the deck at the appropriate temperature. If outdoor temperatures drop below 35 degrees, ground heaters will be installed to maintain temperature.
The remaining section of deck, the girder section, is scheduled to be poured on Friday, Oct. 13. Once the first concrete pour is complete, our team will update the schedule with the second pour date. This is a big day for the bridge team; here’s a toast to good weather.