Ingenuity at its best. Rather than sending it to the scrap-pile, Streb Construction decided to upgrade their 1999 slipform concrete paver with the latest technology - including a 3D machine guidance system for accurate paving without stringlines.
Published: March 2013
Author: Jack Lucic
When tough times hit we see our share of bad things happen, but we see plenty of what we refer to as good old-fashioned ingenuity. That power of creative imagination helps us solve problems, meet challenges, and create new things out of next to nothing.
Now more than ever, ingenuity is flourishing. It is helping businesses in the construction market that have been hard hit by what some refer to as the Great Recession. These companies are using ingenuity to survive and even thrive in the face of one of the most dramatic business downturns the world has experienced.
One such creative innovator is Streb Construction Co., Inc., located in Iowa City, Iowa, USA. Streb understands concrete paving. The family-owned business has been at it since 1965. The company serves primarily Johnson County and surrounding area.
Streb Construction is the kind of company that takes care of its customers, employees, and the equipment it owns. That's why when it came to evaluating the remaining useful life of its 1999 CMI SF3302 slipform concrete paver it was tough. The company could hang on to it or purchase a new paver with its technological advances.
"We were happy with the performance of the CMI paver," states Steve Streb, vice president of Streb Construction Co. "We have had the machine for 12 years, logged a lot of hours on it, so it made a lot of sense to look at a new paver, but..."
The "but" creating the hesitation was the desire to somehow upgrade his trusted old paver so that it could run smoother and stringless. Streb understands the accuracy advantage of GPS machine control and wanted to somehow add it to his CMI SF3302 paver.
"The beauty of stringless is you don't have to work around it," Streb says. "String can be hit by the workers during construction or a truck can hit it or a truck gets too close and moves it and that's what you end up paving to."
Streb adds, "Technology is superior since it eliminates the human error when setting stringline - which has meant eyeballing it to get the profile right. The human eye is only so good."
Streb Construction sought help through Power Pavers, Cedar Falls, Iowa - which was previously owned by CMI. Power Pavers manufactures a full line of two-track concrete paving equipment used in street, highway, and airport construction. Streb Construction pulled in its local Topcon Positioning Systems dealer, Star Equipment, Des Moines, Iowa, which it has worked with in the past. Additionally, Sun Source Hydraulics, headquartered in Addison, Ill., was tapped for upgrading the hydraulics. Sun Source is considered a leader in industrial and mobile fluid power distribution for the past 70 years.
Additionally, Streb Construction added a GSI, Gomaco Smoothness Indicator, to the retrofitted machine. The GSI is a non-contact surface smoothness instrument that uses three different sensors, two sonic and one slope, to read the smoothness data and display it on a real-time, touch-screen graphic display.
All of the companies, with their areas of expertise, contributed to the upgrade of the 1999 CMI SF3302 slipform concrete paver. Ingenuity at its best. A paver which had been innovated, designed, and manufactured in the 20th century was now retrofitted and upgraded to be the peer in capability, performance, and results of a new 21st century concrete paver. The cooperative efforts of the many had paid off.
Power Pavers spent less than two weeks completely retrofitting the CMI SF3302 paver and upgrading it to a "plug and play" capability like its new machines.
"Power Pavers was able to successfully retrofit Streb's machine in that we were the original manufacturer of the SF3302 for CMI, giving us in-depth knowledge its systems," states Fred Hite, general manager, Power Pavers, Inc. "Because the SF3302 has a similar hydraulic circuit as our Power Paver SF1700, and that all of our newer Power Paver machines are virtually "plug and play" with most third party 3-D stringless systems, we were able to successfully install the SF1700 control system and hydraulic components in parallel to the existing system on the SF3302."
With the upgrade made on the machine, it was then capable of running the Topcon's Millimeter GPS Paver System, which uses GPS and Topcon's patented Lazer Zone designed to provide millimeter accurate control for concrete pavers.
Bill Painter, Topcon senior manager for paving systems states, "This was a unique situation in which we installed the very latest technology on an older paver that had been retrofitted to this extent. We are very pleased with the results."
Minute adjustments to the thickness of the paving can be made by the machine operator while paving. Streb sees this capability as a benefit to the county engineers who conduct depth checks.
"If the county engineer says he really wants to bump up the thickness of the pavement - even minimal amounts, say five hundreths or even a hundredth - the machine operator can literally tap a couple times on the Topcon GX50 operator control box and change it," states Streb.
Prior to GPS machine control on pavers, the operator or another worker would need to physically run a measure to the hub and adjust the string to measure the adjustment.
"With the newly installed CANN-based control module and a valve bank on our CMI paver, the machine runs like a new Power Paver SF1700 machine," Streb says. "We now have the first retrofit of a mainline concrete paver in the world running a Topcon Millimeter GPS Paver System. This has eliminated stringlines and other linear references and has increased production."
The machine control technology provides grade reference over the entire project and provides vertical measurement. It is designed to pave transitions, even through horizontal and vertical curves.
If Streb Construction has a smaller job that does not require the GPS Paver System, there is a switch that can be flipped to turn it off and rely on stringlines and wands.
To make certain the retrofitted paver with the 3D-guidance system was operating as expected, the "new" machine did some test paving on a bed of sand to verify performance.
"Before we began using our retrofitted CMI paver on an eight-mile stretch of Iowa County Highway Y14, we literally paved a test bed of sand," Streb says. "All of us were happy to see it function as expected."
The following day Streb Construction had its "brand new" 1999 CMI SF3302 slipform concrete paver on the road project earning its keep.
Based in Chicago, Jack Lucic is a freelance writer covering construction, management, and insurance topics. He can be reached at jacklucic@yahoo.com.