Guntert & Zimmerman
Construction Profiles
Fall 2009
Cold Spring Construction
Hawkins Construction
Thiess
pg. 1
pg. 6
pg. 11
First Dowel Bar Insert in NY
Flynn
Iowa Goes Stringless pg. 9
New Telescopic End Sections
Paving Train in Australia
An Eye For Quality
Cold Spring Construction Paves with First Successful DBI in New York State Change comes slowly. The concrete paving industry is constantly working for more market share in states that have typically been more asphalt friendly. The benefits of using concrete over asphalt have been proven time and time again. Concrete pavements are stronger, longer lasting, more durable, and environmentally friendly. The advantages of concrete pavements are even more dramatic in areas that experience freeze thaw cycles and repeated deicing salt applications. One of those areas of this country is upstate New York, where winter weather coming off the Great Lakes causes extreme snow levels and ice accumulation. The State of New York has not been an active concrete paving market for some time. Part of the reason for lack of concrete activity has to do with previous installations that were poorly constructed. Over time however, concrete pavement design, construction practices, and equipment have evolved. Because of these changes, contractors are able to construct extremely smooth concrete pavements that will last over fifty years with minimal maintenance. With a market positioned to offer the 1
best engineered solution for America’s crumbling infrastructure, there has never been a better time to consider the use of concrete pavements. The New York State Thruway, which owns and operates the I-90 corridor through upstate New York, recognized the inherent problems and short life of the asphalt overlays it was constructing. For this reason it chose to reconstruct a 15 mile (24.14 km) stretch of interstate around Weedsport, NY with a concrete section. Once the design decision was made to use concrete, it was incredibly important to award the project to a contractor that not only was quality minded but also understood the importance of this project and the influence it has on the future of concrete in the State of New York. It was a benefit to the concrete market that Cold Spring Construction was awarded the project. Cold Spring Construction has been a staple of quality and precision in the Buffalo area since 1911. Started by Eugene Forrestel, the
Steve Forrestel Ryan Forrestel
President
Assistant Superintendent
company has been passed down through three generations with the next generation coming up through the ranks. Cold Spring’s success over the years can be attributed to always having an eye for quality. As the concrete market begins to thaw in New York, we can all breathe a large sigh of relief that Cold Spring has represented the concrete market well. When awarded the I-90 job, Cold Spring’s President, Steve Forrestel, went searching for the proper equipment solution. With that keen eye for quality, Forrestel decided to go with a G&Z S850 Slipform Paver. “Our goal is to be as competitive as possible, and we believe the G&Z gives us that capability,” says Steve Forrestel. As the project plans began to become finalized, it was clear that the project would be much better suited using a mechanical dowel bar inserter rather than welded dowel assemblies for the placement of load transfer dowels in the transverse joint. Prior to this project, mechanical dowel bar inserters had never been successfully used in the state, but Cold Spring recognized the quality of the end product, productivity increases, and potential cost savings with its use. Through several meetings and communication between the Thruway, Cold Spring, and G&Z, the Thruway allowed the use of G&Z’s Compact Dowel Bar Inserter (CDBI). A tolerance specification and QA program was developed to ensure the accurate placement of the
Dick Forrestel Chairman
dowel bars in the pavement. The end goal of these collaborative efforts was to ensure 1) load transfer capability of the joint wasn’t compromised due to dowel bar position and 2) the dowel bar could be inserted to meet specification with the equipment being used. There are many criteria for the specification to be met, with the strictest being a vertical and horizontal tolerance of +/- 15 mm along the length of the bar. “During the course of my career in concrete pavement construction, I have never seen 4 different parties (New York Thruway Authority, Cold Spring Construction, Guntert & Zimmerman, and Craig Greene, Hanson) work together in an effort to produce the best quality concrete pavement ever slipformed in upstate New York . This effort started months before the first yard of concrete was ever poured. It was because of this pooling of knowledge, experience, and attention to detail that the optimal concrete mix was designed, batched, and placed which resulted in a quality, durable, and smooth pavement,” said Bill Stewart, Paving Superintendent . The I-90 project near Weedsport, NY is the single largest concrete paving contract ever awarded in the state of New York. The 3 year project consists of 15 miles (24.14 km) of dual lane concrete pavement. The New York Thruway Authority’s I-90 is a major thoroughfare between New York City and the rest of the country. The first of two 5 mile (8 km) eastbound sections were completed 2
in 2009 with three 5 mile (8 km) eastbound / westbound sections scheduled for 2010 and one remaining west bound sections scheduled for 2011. Historically, this particular portion of the NY Thruway has always required intensive maintenance because of the combination of poor soils, freeze/thaw cycles, and exposure to deicing salts. Over the years there have been numerous asphalt overlays on this stretch of roadway sometimes as frequent as every couple of years.
3
Demolition work began in May 2009 with the first concrete paving starting around the Fourth of July holiday. The demolition work consisted of milling off the top layer of asphalt, excavating the old 9 in concrete section, and crushing the concrete to be recycled as sub-base. Even with several undercut sections that needed remediation, the 2nd 5 mile (8 km) section of concrete was completed October 8th on schedule for a traffic move onto the new pavement in mid-November. “The G&Z is well built to handle large piles of concrete in front of the paver which helps us keep up with the plant production and meet our needed production rates,” praises Steve Forrestel.
For this particular reconstruction project, the Thruway wanted to design a pavement that would last 40-50 years with little maintenance other than occasional CPR (Concrete Preservation Restoration) procedures every 10 years or more. CPR is a total system that includes undersealing, partial depth replacement, and spall repairs, grooving and grinding of pavement surface, cleaning and resealing of joints, and shoulder restoration.
Transverse joints are spaced every 14 ft 9 in (4.5 m) with a longitudinal joint positioned in the center of the two lanes spanning the length of the pavement. The transverse joints are reinforced with 1-5/8 in x 18 in load transfer dowels bars, while the longitudinal joint is tied with 5/8 in x 36 in deformed tie bars.
The existing slab was 25 ft (7.62 m) wide with 9 in (22.86 cm) of concrete overlaid several times with asphalt and reinforced with wire mesh. The reconstructed 2-lane concrete pavement section is 26 ft (7.9 m) wide and 13 in (33 cm) thick with a 10 ft (3 m) asphalt shoulder on the right and a 12 ft (3.65 m) asphalt shoulder on the left. The concrete pavement section is supported by a 4 in (10 cm) layer of permeable concrete base over a 12 in (30 cm) sub-base layer of recycled concrete.
Cold Spring purchased a G&Z S850 and CDBI specifically for this project because they knew to meet the tight production schedule and stringent smoothness and dowel bar tolerance specifications they needed the best that technology could offer. Ryan Forrestel, Assistant Superintendent commented, “The S850 with CDBI is an extremely complicated machine but is so well engineered that it performs flawlessly. It is exciting to work around a machine that gives us the capability of putting out the best possible product.”
The S850 with CDBI has performed excellently on the job. Steve Curtis, Paver Operator states, “The S850 worked well from the start. Right out of the box. Everyone at Cold Spring has been really pleased.” Speaking of the dowel bar inserter, Dick Forrestel, Chairman of Cold Spring, states, “It’s now a brand new ball game. This solves the problems and headaches of paving over baskets.” As part of the quality assurance program that Cold Spring submitted to the Thruway, they purchased an MIT scanner and trained one of their young promising engineers to measure the position of the dowels in every joint after each pour was complete. The location of dowels in the pavement has been excellent at the end of phase one 95,186 bars had been inserted with less than 0.5% of the bars misaligned. The majority of the misaligned bars occurred during the first few pours when typical start-up issues with an operation of this magnitude were being addressed. This percentage is well below typical industry standards for projects using either welded dowel assemblies or mechanical dowel bar inserters. Because of the proactive stance that Cold Spring has undertaken by measuring each dowel for its correct positioning, the Thruway has gained significant confidence in the work that Cold Spring performs as well as the performance of the G&Z equipment they use. “Solving the dowel bar issue with a DBI really solves the problem and that’s good for the concrete industry,” says Dick Forrestel.
Extremely sharp edges produced by G&Z’s edger sideforms.
G&Z CDBI poised to insert dowels.
The G&Z requires little to no extra finishing behind the paver.
4
Half Width Slipform Paver
COMING SOON SAME G&Z QUALITY, SAME G&Z SMOOTHNESS.
Guntert & Zimmerman
5
Time Is
Money To the contractor, the well-known phrase “time is money” could not be closer to the truth. Schedules and backlogs pile up, and the need for quality equipment to fulfill needed production rates and schedules is an ever increasing commodity. One of the largest constraints to a concrete paving operation is time consuming paving kit width changes on the slipform paver. With the bidding table becoming more competitive, a contractor that can offer a shorter paving schedule, which offers the pavement ready for use to the highway or airport authority in a faster time frame, often has a competitive advantage. It is no surprise that technology is being designed and developed to achieve quicker width changes to meet the need of contractors who are willing to bid using aggressive production rates. Guntert & Zimmerman (G&Z) has produced such a technology. G&Z’s New Telescopic Paving Kit Terminal End Sections (patent pending) allow the contractor to perform width changes in an extremely shortened amount of time and with fewer personnel. The New Telescopic End Sections give the contractor 6 feet (1.8 m) of quick width change capability 3 feet (.9 m) on each side. In the past, the challenges with similar technologies has been that contractors using quick width change solutions were faced with
Hawkins Construction Paves With New G&Z Telescopic End Sections sacrificing smoothness; this resulted in an inability to use the technology on projects that had a tight smoothness specification. The G&Z Telescopic End Sections address not only the need for quick width changes but also the need for quick width changes without adversely affecting pavement smoothness. It has always been a source of pride for G&Z that its customers are confident in the smoothness produced by the rigid and highly productive S850 and S1500 slipform paving machines. The sacrifice of smoothness was never an option to G&Z design engineers when developing these new end sections. Hawkins Construction Company based in Omaha, NE was the first contractor to take delivery of G&Z’s New Telescopic End Sections. Hawkins bid a project at Eppley Airfield with an extremely aggressive paving schedule. In the past, the options that would have given them any hope of meeting the schedule were to have two to three paving kits on-site sectionalized for each pour or to work the job with two pavers. Using multiple paving kits still requires a lot of break-down and set-up time which requires the use of a mechanic’s crane. The cost of multiple paving kits can be expensive and often times deters contractors from going this route. Using two pavers is definitely a high cost option and
6
slabs consisted of a 17 in (43.18 cm) sand layer, a 6 in (15.24 cm) crushed limestone layer, and a 6 in (15.24 cm) layer of cement treated base (CTB). The runway (14R-32L) section that is being reconstructed is 6,000 ft (1,828.8 m) long by 150 ft (45.72 m) wide. This stage of the project included alternating pour widths of 20 ft (6.09 m), 16.5 ft (5.02 m), and 18.5 ft (5.63 m) for the 150 ft (45.72 m) wide section. The pour widths were laid out by the designer in order to accommodate a specific joint pattern. The Taxiway/ Runway 1836 section that is being reconstructed is 3,000 ft (914.4 m) long and 150 ft (45.72 m) wide. The 150 ft (45.72 m) width was made up of 8 pours at 18 ft 9 in (5.71 m) each.
a logistical nightmare for a contractor who has other projects where the paver could be used. Logistically it is too difficult to move a paver back and forth between jobsites. A contractor must consider the lost productivity when a paver is sitting idle. Hiring a second paving crew to work simultaneously usually is not a solution because the concrete batch plant often can’t supply enough concrete to two pavers. Hawkins and G&Z decided to team up to solve this issue and develop a viable option to gain telescopic capability within the end sections of the paving kit. Over a six month period, the engineers at G&Z, along with input from Terry Kirsch – Equipment Manager at Hawkins, designed the New Telescopic End Sections. While the manufacturing process of the entire S850 Slipform Paver with the Telescopic End Sections was proceeding through the G&Z plant, Hawkins was present at critical design junctions to offer suggestions which led to many design improvements and changes through the process. Terry Kirsch, Ron Mockelman (Lead Paving Mechanic) and Abraham Adame (Paver Operator) from Hawkins observed and participated in the final assembly and testing of the S850 Paver with the Telescopic End Sections.
With regards to the project schedule, the critical path on this project was the 120 day window that the airport gave Hawkins to tear out the intersection of the runways plus 1,000 ft (304.8 m) on either side of the intersection. This is the part of the project that required the greatest number and most frequent width changes with the paver. The Runway 14R-32L section had three different paving widths with almost daily width changes required. Hawkins finished this critical stage of the project in less than half the time given in the allotted 120 day window which allowed the airport authority to open the runway back up ahead of schedule.
Pour Schedule for Week of the July 6th Date
Day of Week
No. of Slips Pavement Dimensions
7/6/09
Monday
2
16.5 X 400’
7/7/09
Tuesday
1
20’ X 400’
7/9/09
Thursday
2
20’ X 400’
7/10/09
Friday
2
16.5 X 900’
Hawkins took delivery of the G&Z S850 on April 20, 2009. The paver has performed above and beyond their expectations. The aggressive schedule they aligned for the paver is no match for the capabilities of the machine. This phase of the Eppley Airfield project consisted of the reconstruction of Runway 14R-32L and intersecting Taxiway/ Runway 1836. All concrete sections were replaced with 17 inches (43.18 cm) of jointed plain concrete pavement with 21 in (53.34 cm) thickened edges in specific locations. The material beneath these
7
2 days of work becomes a matter of hours.
With G&Z’s patented 90 degree steering, Hawkins was able to maneuver the paver very easily from one pour to the next saving valuable time. If one pour happened to be intersecting with another pavement, Hawkins was able to put the machine into its 90 degree steering mode at the end of the pour often leaving just a small amount of hand pour to fill-in. On pavers without 90 degree steering, for purposes of maneuvering the machine out and away from the slab, a much larger section of concrete is often left to hand pour. To protect the machine frame from undesirable torsional forces when walking the S850 over uneven ground, the S850’s cross slope / anti-torsion control system was used. The Telescopic End Sections have given Hawkins an incredible edge. “We can change the width of one side of the machine with two guys in 1 ½ to 2 hours. It takes about 3 ½ to 4 hours to make a width change on both sides. It would normally take us 1 to 2 days to perform this operation,” says Ron Mockelman the lead mechanic on the Hawkins team. The Telescopic End Sections can give the contractor the ability to pave a day sooner compared to a standard width change operation. The smoothness obtained with Hawkin’s new S850 with Telescopic End Sections was exceptional from the start of the first pour through completion of the project. Though the project was only specified with a 2/10’s blanking band specification, Hawkins was curious to know how smooth they could pave with these new end sections so they analyzed the profilograph traces under the 1/10th and zero blanking bands as well. The average of the results under a 2/10th’s blanking band was in the LOW single digits as measured in inches per mile, while the 1/10th and zero band results were 10-15 inches per mile and 18-22 inches per mile respectively. Both Hawkins and the Airport Authority were very pleased with the smoothness obtained on this project.
As a side note, Hawkins poured several slabs using a previously poured companion lane slab to establish grade and alignment while also using G&Z’s patented cross slope control feature. This allowed them to pave without setting a single stringline for these passes. Terry Kirsch reported that the smoothness results under this scenario were well within the 2/10th’s blanking band specification. With thousands of yards through Hawkins’ G&Z S850 paver already, it is evident the S850 with the New Telescopic End Sections has met the standard G&Z sets for itself and has exceeded the needs of the contractor. Terry Kirsch said of the partnership, “The venture between Hawkins and Guntert & Zimmerman was great. The quality of the work was always the highest standard.” The S850 itself was a huge timesaver since it allowed Hawkins to pave different Patent slab widths everyday without any down time. In the Pending past this same production with varying widths was performed with two pavers owned by Hawkins. Ron Mockelman and his maintenance crew have had nearly no problems with the S850. The only regular maintenance has been to grease the plow and jacking columns. One of the greatest time savers for the maintenance crew is the ability to wash down the S850 in a minimal amount of time. The open engineered design allows for ease of clean up and leaves few small spaces for concrete to stick and dry. The word coming out of Eppley Airfield from all those at Hawkins is, “We could not have met the current schedule with any other piece of equipment than the S850 with the Telescopic End Sections.” In fact the concrete pavement produced by the S850 is so superb that Hawkins is eager to finish their work at Eppley Airfield to move the machine to other projects they have in the area.
8
Iowa Shows Its Stuff And Goes Stringless
The construction industry has been using stringless technology for elevation and steering control of equipment for a number of years. To date however, the use of this technology in the concrete paving market has been limited to the grading operation and is not typically used for the actual paving where stringline is still the preferred method of guiding the steering and elevation controls on these machines. This is due to stringline having been traditionally more reliable for paving operations than a stringless system when it comes to meeting the strict smoothness specifications often found on highway projects. In a business where smoothness reigns supreme, contractors can’t simply throw caution to the wind and pave with a system in which the reliability has not been proven. Even with this in mind, the stringless benefits are undeniable: less survey costs, fewer man hours setting stakes and string, and no more office types tripping over “hard to see” stringline on jobsites. For a paving contractor, the savings associated with stringless technology simply doesn’t outweigh the cost of grinding out of specification pavements. As the technology has progressed, the
9
paving market has become more and more interested. Is it finally time to see the broad use of stringless technology in the paving market? Once again, the constantly innovative Iowa DOT has set out to be a leader in the application and use of new technology. On September 2, a national open house for concrete overlays was held in Worth County, IA. Over 100 state DOT employees (9 states), county engineers, engineering consultants, contractors, and suppliers attended the one day event. The agenda for the day featured concrete overlay projects by both Cedar Valley Corp. and Flynn Co. Inc., who both use G&Z S850 slipform pavers. Presentations by James Cable of Cable Concrete Consultation LLC, Tom Cackler, Director of National Concrete Pavement Technology Center, Matt Morrison, Paving and Key Accounts Manager for Leica, Ron Guntert, President & CEO of G&Z, and Jeff Flynn, President of Flynn Co. Inc., were followed by a bus tour of both jobs. Cedar Valley recently completed three Worth County projects. The 24 mile (38.6 km) long, 4 in (10.16 cm) thick, 22 ft (6.7 m) wide
concrete overlay which was paved with traditional stringline, was selected through an alternate bidding process over a 3 in (7.62 cm) asphalt overlay with 3 in (7.62 cm) cold-in-place recycling. Because of concrete’s longer life expectancy and lower maintenance costs, Worth County officials selected concrete as the material of choice for their overlays rather than asphalt. For the quality of work achieved on this project and the hundreds of concrete paving projects previously done by Cedar Valley using a G&Z S850, G&Z is very proud to call them its partners. Flynn’s 10.5 mile (16.9 km) Iowa Department of Transportation project on Hwy 65 near Mason City, IA was a 32 ft (9.75 m) wide, 5 in (12.7 cm) thick unbonded concrete overlay using a stringless system. The original 24 ft (7.3 m) pavement was widened 4 ft (1.2 m) in each lane, and Flynn elected to pour at half width to facilitate local traffic. Iowa DOT specified the use of stringless technology on this portion of Hwy 65. Flynn’s G&Z S850 was equipped with Leica Total Station machine controls. As the name implies, stringless technology replaces the traditional stringline with an electronic tracking process that controls the horizontal and vertical operation of the paver. At times, Flynn paved up to 18 fpm (5.48 mpm) achieving smoothness on zero blanking band as low as 6 in per mile and averaging in low teens for the project which earned them full bonus incentive.
the first time was Ames Engineering’s prototype, a real time on board smoothness measuring device. Jeff Flynn and his team should be congratulated for paving the way to a brighter future with stringless paving technology. Based on the extremely positive reaction of county officials and attendees at this event, the future of concrete overlays and stringless technology looks very promising. Iowa alone is building over 200 miles of concrete overlays in 2009. The Flynn Company’s constant attention to detail from the project planning phase through installation is one of the reasons that they are considered a quality paving contractor. G&Z would like to say a special thanks to the Flynn Concrete Paving Team: Mark Gorton, Project Manager, Gary Hoffmann, Superintendent, and Tim Duffy, Paving Foreman for helping bring this new technology to the market.
With the savings in materials and labor, concrete overlays will be equal to or lesser than asphalt’s initial costs but will always perform better over the long run. This could result in more jobs bid for concrete rather than asphalt. With the elimination of stringline, the use of stringless technology holds special potential for increasing the application of concrete overlays. Also seen for 10
What More Could A Contractor Ask For? Thiess Paves With Complete G&Z Concrete Paving System The construction of concrete roads can be likened to a ballet, if the contractor, owner, and designer are in step it can be pulled off flawlessly. If not, it can be a contentious battle. The true fact is that it benefits both parties to produce long lasting, smooth, and durable product. As with constructing any large scale project, it takes many different pieces to come together for a paving project to run smoothly both in operation and end product. The mind set the contractor and authority take when going into the project can drastically affect the outcome. If the contractor and authority purpose to focus on quality, plan correctly, and work together the end result can be an unbelievably successful project. G&Z has been honored to be a part of such a project in Australia. In late 2006, Thiess Pty Ltd. started initial investigation into new concrete paving and mixing equipment for a large design build highway project in eastern Australia along the Pacific Highway. Thiess Pty Ltd is a wholly owned division of Leighton Holding Group one of the largest contractors in the world. Thiess was a part of a team called The C2HC Alliance, comprising of Thiess and Parsons Brinckerhoff, who were eventually awarded the project in the spring of 2007 as the New South Wales Road & 11
Traffic Authority (RTA’s) alliance partner to upgrade a 32.7 km (20.3 mi) section of the Pacific Highway on the New South Wales mid-north coast. Located between the regional centers of Taree and Port Macquarie, the project involves upgrading the existing highway between Coopernook and Herons Creek with a focus on providing a high standard four-lane dual highway. The upgrade of this section of the Pacific Highway will significantly alleviate its poor safety record, reducing serious accidents and fatalities along this stretch of road. The Thiess / Parsons Brinckerhoff team was selected because it was recognized as having the right vision, necessary experience, capabilities, understanding, innovative approach and commitment to work with the RTA. The RTA and Alliance’s key objectives related to program, safety, quality, environment, and community requirements. Key factors in the selection process included: the Alliance’s high level of teamwork; the reputation and integrity of the organizations and team members; and its proven ability to perform.
This AUD$470 million (US$430 million) project is the longest stretch of the Pacific Highway to ever be constructed as one project. The 10.5 km (6.5 mi) section between Coopernook and Moorland is comprised of 3.5 km (2.17 mi) of new two lane highway and a 7 km (4.3 mi) duplication of the existing highway, and a single bridge over Two Mile Creek. The 22.2 km (13.8 mi) Moorland to Herons Creek section comprises 5.2 km (3.2 mi) of new two lane highway and 17 km (10.5 mi) duplication of the existing highway. This section includes 16 new bridges and 52 culverts. The project is a missing link in the Pacific Highway and joins dual highway sections at each end. There are 3 interchanges along the length of the project. The unique approach where the specifying authority was a part of the team helped to quickly eliminate any impairment to production or quality during the design stage and through construction. For example, bridge approaches were redesigned to accommodate the movement of the paving equipment over the bridges and to minimize hand paving. The team’s commitment to quality was also emphasized and evident in the final specification and contract. Because of the potential monetary incentives in place for the contractor if they met or exceeded certain measures of pavement quality, there was a large push for the contractor to produce a durable, smooth and quiet concrete pavement. These
potential quality incentives were a big consideration in the team’s selection of concrete materials and equipment. For example, natural river sand was trucked in from over 200 km (124 mi) away to ensure good slipform concrete mixes and four different quarries were used to supply aggregate and sands. Concrete mix designs were done using Shilstone software to optimize the aggregate gradations. During the tender phase of the project, the Thiess Plant Department undertook a review of the required paving resources for the project and identified that a complete new paving train and two new batch plants would be required to complete the project in the allotted time. Prior to the equipment selection team’s tour of the United States, a desktop review of the available options with respect to multilane paver manufacturers around the world was completed. After a thorough selection process, the selection team recommended to the Thiess Pty Ltd management team to purchase the new paving fleet from Guntert & Zimmerman. The recommendation was accepted and the new fleet was delivered to site and commissioned in late 2008. The new fleet consisted of an S1500 Paver, PS1200 Placer Spreader, and two TC1500 Texture Cure Machines. 12
Thiess also commissioned G&Z to design a portable and modular batch plant based on their existing MCP12 design to suit conditions in Australia. The Thiess / G&Z team have successfully built and commissioned two of these plants in Australia. These plants are now setting a new benchmark in concrete production and quality in this country. G&Z looks forward to bringing further information regarding the implementation and operation of Thiess’ batching process in a future issue of G&Z Construction Profiles. Thiess is now approximately 50% complete with the Portland Cement Pavement (PCP) installation and targeted to complete the project by April 2010. Monthly production has peaked at nearly 30,000m3 (39,270 cy) during August 2009.
Some of the benefits identified when deciding on the G&Z paving machines were: • 90 degree steering capability – very useful on a tight site and because the project includes some 27 traffic switches, the multiple paving spreads including concrete plants are constantly moving along the project to allow the complex staging to be completed. This was further complicated by prolonged rainfall during 2008 and first half of 2009 which meant over 40% of available days were lost due to wet weather. • Double telescoping tractor frame – ability to telescope to extend rather than to add in / bolt in frame sections to extend • Paving kit section – reduced bolts per joint and machined connections mean less time in kit changes • Spreader plow – very effective in moving concrete and easier to change widths • Fine width kit adjustment – ability to fine tune width of kit • Hydraulic side forms – split forms make it easier and faster to back over end of runs According to Todd Myers, who headed the Thiess equipment selection team, “The G&Z machines were delivered on time and the site commissioning process went without incident. The machines were ready to go to work without any modifications. G&Z’s service team provides great support, and they really know the machines.” Myers went on to add that “The back up service provided by G&Z is second to none. Any issues raised are acted upon immediately. They are able to provide not only operational support for the machine, but also advice on mix designs and the benefits of on-ground experience. The performance of the machine to date has been excellent with the quality of the pavement produced to date exceeding expectations. While the G&Z S1500 machine may not be the cheapest on the market, we believe that it is the best value for the money. It’s a big capital investment, but one that has provided good returns in the quality of the pavement and reliability of the machine.” 13
With regards to the smoothness results achieved to date, in Australia they go by a NAASRA smoothness reading which is total counts per km as measured by an laser profiler. They take the mean of all the readings of the lots + standard deviation of all the lot readings. Less than 35 earns 100% of full bonus. To date Thiess is running at 30.6 which is considered by many as the best in Australian concrete paving industry. Their first day of paving was a 36. A 42 earns no bonus but no corrective work is required. A 49 requires grinding into specification but you cannot grind into smoothness bonus. The best Thiess had previously done was a 33 but most other projects in the past had been in the low 40s. The subject of noise is closely related to pavement smoothness as well as texture. The PCP pavement placed by Thiess is one of the quietest of all Australian PCP pavements placed in the past. Of the two sections measured one was 80.4 dBa and other was 82.5 dBa. Noise measured by a drive by test where a microphone is placed 7.5 m (24 ft) from the CL of the vehicle traveling at a speed of 100km/hr (60 mph).
The pavement surface was dragged with a Hessian fabric followed by transverse tining. Tine depth is 1 mm (.03 in) and width 3 mm (.11 in). Tine pattern is random with widest 19 mm (.75 in) and average spacing 12 mm (.47 in) and the pattern repeats every 250 mm (9.8 in). A trial of longitudinal diamond grinding to evaluate reduced noise was also carried out with results surprisingly high. These high results were put down to a low number (200) of blades per 4 ft. Drum vs. recommend 220 to 240 per drum to reduce fin size left. Large fins have been found to contribute to noise. An exposed aggregate trial completed by another contractor for the RTA some 10 years ago showed very similar noise levels (81dBA) as achieved by Thiess with the transverse tining on this project. The combination of consistent concrete from the new G&Z batch plants and the quality of the tining from the new TC1500 machines is credited with producing the low noise values.
Job Facts Pavements Design PCC 150mm lean Mix Subbase (5Mpa) 260mm Base (35mpa) Base concrete is Unreinforced Plain Concrete with sawn skewed transverse joints at 4.2m spacing. Single sawn blade longitudinal joint. Subbase paved at 10.1m wide. Base paved at 8.0m wide. The placer spreader was used for all base to pre-spread. Shoulder paved in a subsequent operation with shoulder paver at 2.0m wide or 3.0m wide if a gutter is required. Pavement Design Low Noise 220mm thick Lean Mix Subbase (5Mpa) 175mm thick Dense Grade Asphalt 30mm thick Open Grade Asphalt Total project length is 32.7km of dual carriageway. Pavement types Existing Highway reuse 4.5km Plain Concrete Pavement 46.5km Low Noise 10.5km Structures 1.8km Concrete Quantities Total Subbase 122,000m3 Total Base 152,000m3 Structural Concrete 46,000m3 (Bridges box Culverts Etc)
14
G&Z TEAMS UP WITH
TO BRING YOU THE
PORTABLE MODULAR CONVEYOR
The conveyor is conveniently controlled from the loader controls inside the cab of the loader. The speed of the belt is controlled by the engine RPM and the flow of oil through the control values. The folding and travel features are controlled from auxiliary controls on the conveyor base at ground level.
For more information, please contact John Eisenhour at (405) 371-5180 or Ron Meskis at (209) 568-7406.
Guntert & Zimmerman Const. Div., Inc.
222 E. Fourth St. Ripon, CA 95366 U.S.A. Phone 209-599-0066 Fax 209-599-2021 Toll Free 800-733-2912 Email gz@guntert.com Web www.guntert.com
Construction Profiles is published by Guntert & Zimmerman to inform readers of applied construction technology utilizing Guntert & Zimmerman equipment. All rights reserved. The contents of this publication may not be reproduced either in whole or in part without the consent of Guntert & Zimmerman. Printed in U.S.A.
Manufactured under one or more of the following U.S. or Foreign Patents: 4,433,936; 4,483,584; 0051885; 6,390,727; 6,390,726; 6,176,643B1; 5,135.333 and 117323 and Patents Pending. Some items shown may be optional. G&Z reserves the right to make improvements in design, material, and/or changes in specifications at any time without notice and without incurring any obligation related to such changes. Brochure No. 400P101