Form+Function NEWS & INFORMATION FROM HAMILTON FORM SUMMER 2016 Project Spotlight The Herbert C. Bonner Bridge CYLINDRICAL PILE FORM Coastal Precast Systems, Chesapeake, Virginia The North Carolina Department of Transportation awarded a design/build contract to replace the Bonner Bridge, connecting Hatteras Island with the mainland, to PCL Constructors with HDR Engineering as the lead design firm. The 2.8 mile bridge will have a maximum span length of 350 feet and a vertical clearance of 70 feet. The bridge is designed for a 100-year lifespan and will take advantage of accelerated bridge construction techniques, and that means precast concrete. Coastal Precast Systems in Chesapeake, Virginia is supplying the precast products for the project, including 36-inch square piles, FIB96 and FIB45 beams, columns, pier caps, segmental sections for the super structure and cylindrical piles. Hamilton Form delivered several forms for the project. One of the most intricate is the hydraulically actuated cylindrical pile form. The 54-inch outer form is made in two parts. The base is permanently installed in the bed. The top of the form bolts in place and is removed for stripping product. Vibrotrack is installed on the lower section of the exterior form to help consolidate the concrete. Both the base and top sections have threaded adjustable coil rods bolted through the exterior of the form that act as void hold ups and hold downs. An interior core forms the void. The core is hydraulically actuated to collapse the void in order to strip the product. Voids were built in various lengths to be assembled for different product lengths. The project calls for 138 cylindrical piles varying from 94 to 138 feet long. Coastal Precast Systems used the casting procedures recommended by Hamilton Form for setting up and stripping the product. The form is easy to set-up and the interior void collapses just as intended, comments Joe Rose, Vice President of Sales at Coastal. The surface finish of the product is beautiful and the form has met no, exceeded all expectations. The interior void hydraulically collapses. It is held in place with threaded coil rods in the top and the bottom of the exterior form.
Formwork Adjustable Column Form METROMONT CORPORATION In any precast plant, there are some hard-working forms. One of them is a column form. Hamilton Form recently designed and delivered an Adjustable Column Form to the Metromont prestress plant in Hiram, Georgia. The form package consisted of an eight-foot pallet and 33 side forms. There are two bolting locations on each side of the pallet to produce 48 wide and 72 wide products. Although there are only two bolting locations, the side forms can be adjusted to produce products from 72 down to 18 widths with the use of an adjustable outrigger system. The outrigger system eliminates multiple bolt holes on the pallet. The outriggers are unique in that they can be adapted for different bolting locations. Each has six bolting locations. The bolt holes are offset from left to right for even and odd spacing. The even side of the outrigger is used when the distance from the centerline of the product to the casting skin is even. When the centerline of the product to the casting skin is odd, the outrigger can be rotated 180 degrees to use the odd bolting locations to set the side forms. By positioning the outriggers on the left and the right and rotating for odd or even dimensions, the side forms can be adjusted in one inch increments. By adjusting the side forms at different widths and using headers in between sections, different size columns can be produced from the same pour. The 8 pallet has only two bolting locations on each side of the pallet. Although there are only two bolting locations, the side forms can be adjusted to produce products from 72 down to 18 widths with an adjustable outrigger system Outriggers have six bolting locations and can be flipped from right to left to adjust the side forms at one-inch increments Top ties are used with the form to resist the hydrostatic pressure on the side forms when the concrete is placed. The top ties are made with coil rods that adjust for different product widths. The top ties were provided with two coil rods; a short rod for products 24 or less, and a longer rod for wider products. The design of the form work with adjustable outriggers and top ties delivered on Metromont s request for a user friendly column form that can be easily adapted for different column widths. Mike Stiles, Metromont s plant manager agrees, The best thing about this form is the quick and easy way we re able to fasten it down. The outrigger system makes adjusting the width easy, and we like the design of the adjustable top ties. We added a PVC pipe that fits around the top ties coil rod. The PVC sleeve keeps concrete off the top ties, making it easier to disengage when it s time to strip. All in all, we re pretty happy with the form. Corbels placed in the form If you re ready to add a similar form in your plant, e-mail us at: sales@hamiltonform.com or call 817 590-2111 A PVC sleeve keeps concrete off the top tie coil rods
Equipment Spotlight Tarp cart rides on form with bow rack When More Means Less MULTI-FUNCTION MACHINES MULTIPLY PRODUCTIVITY IMPROVEMENTS Hamilton Form designs and builds tarp carts and utility machines that help mechanize many typical casting processes. The machines we build are intended to make working around the forms faster, easier, safer and less labor intensive. As the labor market has become tighter, we ve noted increased interest in our tarp carts and utility machines. Another trend worth noting: the equipment we build today is more multi-functional than in the past. Glenn Prewett, mechanical engineer at Hamilton Form, designs our machinery and often consults with our sales department and customers during the design process. Customers are asking for new machines that do more than the machines we have built in the past; or not so much more, but mixing and combining different functions in new ways, says Glenn. We build two types of machines to service forms: tarp carts and utility machines. Both can be customized to do more than one process. Both can be designed to operate by riding on the machine or by remote control. TARP CARTS Tarp carts are one of the most popular machines we build. The cart typically runs on the edge of the form, or it can run on tracks next to the form. The cart carries a roller that dispenses a curing cover over the form. Tarp carts are often built for double tee or other long-line forms and for especially wide or high forms that can be difficult to cover manually. Many of the carts we design are built with a bow rack used to carry tarp bows to support the tarp so that it doesn t touch the concrete. Tarp carts can also be built with strand pulling capacity or a deck for mesh. Tarp cart runs on tracks next to the form Tarp cart being installed on tracks next to a tall beam bed
Equipment Spotlight Utility machine with mesh deck and jib crane Utility machine with brush and strand puller Utility machine with an oiler and strand puller Utility machine with screed UTILITY MACHINES Utility machines can be designed with more than one function. We have designed machines that combine a deck brush to clean the form with strand pulling capabilities. We ve also added jib cranes to our utility machines. Another popular combination is an oiler and a vibrating and/or oscillating screed. While combining two and sometimes three functions in one machine improves productivity and return on investment, it s not practical to build a machine with several functions that require increasing the horsepower of the engine. The size of the engine has a big impact on the cost of the machine, and there are EPA regulations to consider when purchasing high horsepower engines. Tarp carts and utility machines can save time and labor by mechanizing some of the most difficult production tasks. And they are especially valuable for improving safety when working in tight or hard to reach places. When you re ready to invest in machinery to help mechanize some of your production practices, think about what process you might want to combine such as deck or stem brushes to clean the casting surface, a tarp roller, vibrating and/or oscillating screed, form oiler, strand puller or a jib crane then, contact us at 817 590-2111 or sales@hamiltonform.com
Technically Speaking Wait Before You Weld Some precasters have attempted welding, grinding and/or sanding seams on their steel forms in an effort to make the seams less noticeable. This process can have mixed results. While experienced finishers may be able to improve seams, more often than not, the process can make the surface worse. CAUTION Before you weld Beware. When heat of any kind is introduced to steel surfaces; the molecular structure of the metal changes. Welding pulls the surface of the metal together and can create a dip in the seam, making the seam you are trying to minimize more pronounced, defeating the original purpose. At Hamilton Form, we never weld on the surface of the form s skin when we fabricated forms. Seams are only welded from the underside of the form while supporting the fitted pieces together to make sure we do not cause a depression at the seam. EXPERIENCE COUNTS Welding is more of an art than a mechanical process. It can t be automated and is best done by an experienced welder. Our welders are highly trained and have years of experience. This experience can t be easily duplicated. Keep this in mind before you consider making changes to the casting surface of your forms. IMPROVED PROCESSES New equipment and fabrication techniques have greatly improved the quality of seams when fitting sheets of steel in the production of our steel forms. Today, Hamilton Form utilizes a high definition plasma cutter that creates clean edges for fitting sheets of steel. In fact, although you may see a seam on some of our forms, if you rub your hand over it, you may not feel the seam, resulting in a better quality form and a better quality precast product. A high definition plasma cutter creates clean edges, making it easier to fit sheet material together. No Grinding! Grinding and sanding of any kind can destroy the surface of the form s skin. Raw steel has a mill finish which forms a protective coating on the surface of the metal. Grinding and sanding removes that coating and exposes the metal. A light sanding with 60-grit or finer may be acceptable, but be careful not to damage the surface of the steel.
Hamilton Form Company, Ltd 7009 Midway Road Fort Worth, Texas 76118 Ph 817.590.2111 Fx 817.595.1110 www.hamiltonform.com PCI Foundation S tudents and Professor Brad Bell from the PCI Foundation sponsored studio at The University of Texas at Arlington recently visited Hamilton Form. The students met with the HF engineering staff and toured the plant. The group gained insights into the form making process and learned more about the precast/prestressed industry. The PCI Foundation partners with architectural, engineering and construction management programs around the US to help students learn and become exposed to the precast industry in a progressive and dynamic environment. If you want to learn more about the Foundation, go to: www.pci-foundation.org.