Ahead of the game
By Lindsay Gale15 September 2015
Safety, environmental and timeliness issues had to be all carefully accounted for when it came to the demolition of a highway overpass in southern California. Helping to ensure that the project was completed on time with a minimum of delays was a Rammer 4099 breaker which worked for 22 hours straight, “never skipping a beat”.
Removing a sizeable structure, such as a highway overpass, requires planning and preparation before the first piece of equipment rolls onto a worksite. This is particularly true when the demolition project occurs on one of the most heavily congested freeways in southern California. Safety and environmental issues including dust suppression, sound suppression, re-routing of automobile traffic and the recycling of scrap and other re-usable materials must also carefully be considered.
These variables all came in to play when Environmental Remediation Services, Inc. (ERSI), a customer of Tracey Road Equipment, which is an Allied Construction Products, LLC Distributor (Sandvik Construction’s authorized distributor for Rammer in North America), was contracted to help widen the Route 91 Corridor in Corona, California. A key part of the project was bridge demolition at the Interstate 15 and 91 Corona interchange. To help alleviate traffic congestion flowing through Corona, a majority of the work had to be done at night. Working over active railroad tracks and storm runoff channels added another “wrinkle” to the project.
“The close proximity of the railroad tracks had to be accounted for,” said on-site ERSI Superintendent Glenn Beam. “The trains were running close by the overpass so that gave us a limited work window.” Fortunately, issues like this and others were planned for in advance. “This project was bid as a Design-Build and was funded by the State of California along with some Federal assistance. In a Design-Build, teams work together to come up with a good plan and calculate accordingly,” said Glenn.
One of the plan’s primary considerations was much of the demolition work was being performed in elevated conditions over long periods of time. For that reason, ERSI chose the Rammer 4099 hydraulic hammer to demo the overpass. “We were working the Rammer 4099 in high elevation scenarios for a solid 22 hours. It got no break and performed extremely well. It’s the best power-to- weight hammer. For the Komatsu 360 Excavators we use, the 4099 has optimal balance and torque,” said Glenn. Enhancing its productivity and effectiveness the Rammer 4099 also provides an operator-friendly environment in the cab of the carrier for the operator.
So that the highway never had to be shut down completely, the work was done in phases further explained Glenn. “Our timetable had us doing the work in sections. This allowed us to build back what we took out, add the new lanes; all while keeping the lanes open that weren’t demolished.”
As work began, excavator crews started in the middle of the overpass and moved outward. “To balance the load, we sectioned the bridge in half. The excavators then worked in opposite directions. We had a slotted deck that allowed us to drop the concrete and rebar below,” explained Glenn.
The demolition team then focused on lightening the girders. “First, the Rammer 4099 hammer knocked the concrete off and it fell to the deck. Then, we pepper-screwed the rebar and it fell on top of the concrete. We did the same thing with abutments - we peppered-screwed the end-caps.”
Not only was the Route 91 Corridor project executed with precision and accuracy, it beat the anticipated completion date. “Because of the performance of the 4099 Rammer hammer, we were able to open up the Interstate 15 and 91 Corona interchange 11 hours ahead of schedule,” said Glenn. “The Corona site presented both intense and extreme conditions. The 4099 hammer was running for 22 straight hours and it never skipped a beat.”