Tight Timetable, 6:1 Slope, Multiple Elevation Pads Ideal for Trimble GCS900 Grade Control System with GradeMax
Mid-Century modern is a label used to describe architectural, furniture, and product design that was created in the mid-20th century. The style descriptor fits the expansive window walls and arcades of poured concrete columns found in the school and nearby rectory of Omaha, Nebraska's St. Richard's Catholic School. Both were built in the 1960's.
Closed and vacant since 2009, the buildings are now a part of a renewed-use project for the nine-acre site-a new $22 million intergenerational campus that will serve senior citizens and others who are at or below 50 percent of the Area Median Income (AMI).
Work has commenced on renovating the school and rectory buildings and developing the site for 44 energy-efficient, handicapped-accessible cottages requiring multiple-elevation building pads to comply with ADA requirements.
Heimes Corp., Omaha, Nebraska, is the subcontractor for the site grading and all the sanitary pipe and paving work. This is a $5 million project for them. Holy Name Housing is the owner and will be administering the various planned social service programs with Heartland Family Service once the facility is completed and up and running.
The St. Richard's Housing site has challenges.
"There's about a 40-foot elevation drop from one end to the other," states Chad Henry, grading superintendent at Heimes Corp. "We're performing all the site prep and following the contour of this hill which follows a six-to-one slope."
What Henry initially found on the site was an open field area, with a road running through the middle of it. The soil conditions were high-moisture clay.
"We removed the existing road, did the clearing and grubbing work," Henry says. "I believe we removed about 6,400 square yards of paving there before we started the site grading and pad work."
Heimes' responsibility included creating the digital site plan, using Business Center - HCE. The software was reported to be essential to the data preparation for the Trimble machine control and site positioning systems used on the project.
With its 3D digital plan in place, Heimes Corp. tasks include performing 25,000 cubic yards of cut-to-fill, 8,000 cubic yards of export, installing approximately 13,000 linear feet of sanitary sewer, 15,000 linear feet of storm sewer, 2,000 linear feet of water main, and the excavation for two storm water detention cells. A concrete subcontractor working for Heimes placed about 8,500 square yards of concrete for roadwork, which included parking lots and parking trays.
The timetable of six months for Heimes Corp. was tight because the owner wanted to see physical evidence by mid-summer of house structures being built on the pads the company was creating. The entire St. Richard's Housing site project was completed before the December 30, 2012 deadline.
"On every aspect of the grading operation we used Trimble technology to help us complete our end of the project," states Henry. ""We were already using Trimble® GCS900 Grade Control Systems with GPS on our dozers and soil compactor, and we upgraded our John Deere 764 HSD High Speed Dozer to the latest version of GCS900 with the new GradeMax™ technology for dozers."
The company has been using construction technology since 2005. So, they felt comfortable trying the Trimble GCS900 Grade Control System with GradeMax on their John Deere 764 HSD and were able to offer functional comparison between the Trimble GCS900 Grade Control System and GradeMax.
"GradeMax technology makes the Trimble system faster," Henry says. "The processor seems to run quite a bit faster for changing offsets and changing designs. And the other great benefit is you can adjust your valve speed as you're moving. The on-the-fly valve adjustment is probably the most impressive thing that I've seen."
Henry continues, "We're able to save the time it takes to get to accurate grade. Instead of making three test passes, you make one. By the time you're done making your test pass, it'll be adjusted to how you want it to be."
The advantages of the Trimble GradeMax were noticed immediately on the St. Richard's Housing site.
"In addition to the faster speed, we found the Trimble GCS 900 system especially helpful in the later stages of completing the project where we needed to jump from one task to another," Henry states. "We could place topsoil with it and use it to backfill curbs and re-grade and clean up building pads where necessary. It's really priceless knowing it has that versatility."
With respect to the challenges of the St. Richard's Housing site, Henry says: "Considering the challenges of the multiple step building pads, I can not imagine working on this project without GPS 3D machine control. The Trimble GCS900 system helps the machine operator jump from one task to another, while maintaining grade throughout."
Surveyors were used to stake all the finished grades on the building pads when they were completed. They also staked the road after the Heimes crew had completed the sub grade prep and work for the concrete placement.
"The staking was pretty minimal compared to what would have been required if we if we didn't have the Trimble systems," Henry states.
Throughout the project, Henry maintained a four- to five-worker crew. He admits that if they were not using Trimble technology, the work would have required more workers on site.
"It would have cost us easily 25 percent more to complete the project without Trimble technology. There definitely would have been more people involved and it wouldn't have been completed nearly as fast," states Henry. "The project would have required more machine operators, more grade checkers, and there would have been a lot more survey work for the surveyors and ourselves."
Henry says: "We used dual mast Trimble 3D GPS technology for nearly everything. We use the GPS equipment to build all the pads, to do all the road grading. We use our GPS on our excavator to do all the wall excavations, and then we load out our excess dirt with our GPS excavator, and that eliminates the dozer or anything else being with the machine. If you look at it, each portion of our job that runs, there's Trimble technology guiding that area of the job." Henry states that their Trimble dealer "has been key to our success with the technology. We receive training and support every step of the way. Just fantastic."
The Heimes Corp. portion of the St. Richard's Housing project has been completed while the homes are still being built. When the first residents begin moving in, Henry says that he and his crew will have a lot to recall.
"I'm sure we'll remember the way it looked prior to starting, before we did any work there. And we won't forget building and grading those 44 multi-level building pads on this site with its 40 foot of grade change. I'm sure someday after it's up and running I'll drive in there and be thankful we had the 3D GPS technology available."