If ever a bridge needed to be replaced, it s the Sylvan Avenue

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1 Form+Function NEWS & INFORMATION FROM HAMILTON FORM SUMMER 2013 Project Spotlight Sylvan Avenue Bridge Dallas, TX Bexar Concrete Works I, Ltd. If ever a bridge needed to be replaced, it s the Sylvan Avenue Bridge that crosses over the Trinity River just east of downtown Dallas. The bridge has been plagued with frequent flooding and frequent closures for years. Finally, a new precast bridge, elevated above the flood plain is being built to replace the old bridge. Frequent flooding, bridge closings and subsequent traffic jams made the replacement bridge a high priority. Formwork The new six lane; 23 span bridge is being built with a combination of pre- and post-tensioned I-girders produce by Bexar Concrete Works in San Antonio, TX. While most of the spans are made up of typical 82-inch TxDOT prestressed girders; nine of the spans will be built with modified I- girders that are spliced and post-tensioned to cross over the 250-foot mid-span of the river. The modified 82-inch girders are cast on two 50-foot long soffits that slope up to four feet at each end to create the centerline haunch. The girders use significantly more steel reinforcement and are two inches wider than typical TxDot82s. To accommodate the added width, Hamilton Form designed the soffit with one-inch spacers on each side that can be cut down and used to cast typical 82s when this project is complete. (continued)) The soffit slopes up four feet.

2 Project Spotlight Sylvan Avenue Bridge Continued from page 1 TxDOT82s were cast with special 7 and 10 foot end blocks. Each embed plate has 40 6 x 7/8 steel studs. The formwork also included two 8½ foot end blocks which are used back-to-back at the center of the beam to create a blister, or thickened section forming the interior diaphragm that bears on the pier. The typical TxDOT82s were cast with seven and ten foot long girder end blocks. Embed and Bearing Plates In addition to formwork, Hamilton Form fabricated the bearing and embed plates for the project. Most of the beams use 35x60-inch embed plates that are 1-inch thick. Each of these plates has forty, 6 7 /8 -inch steel studs. Each plate weighs 620 pounds. The larger beams use 55x44-inch beveled, galvanized steel bearing plates that are two inches thick. These larger plates weigh in at 1,850 pounds each! The 55 x 44 beveled bearing plates weigh 1,850 pounds each. Nation s Bridges Earn a C + According to the American Society of Civil Engineers, the nation s bridges get a score of C+ on its 2013 Report Card on U.S. Infrastructure. The report cites 66,749 bridges that are structurally deficient and 84,748 functionally obsolete bridges across the USA. In total, one in nine of the nation s bridges are rated as structurally deficient. Although the number of structurally deficient bridges has declined from a high of 77,863 in 2005; today s 66,749 structurally deficient bridges make up one-third of the total bridge decking area in the country, illustrating that those bridges that remain classified as structurally deficient are significant in size and length. The Federal Highway Administration (FHWA) estimates that to eliminate the nation s deficient bridge backlog by 2028, we would need to invest $20.5 billion annually. Currently, only $12.8 billion is being spent. In the past several years a number of innovative concepts have helped make up for the short fall in goverment funding. ABC (Accelerated Bridge Construction) and Design-Build contracts have reduced costs and delivered projects faster. P3 (Public/ Private Partnerships) have provided new funding streams. And, precast concrete is being even more widely accepted for its speed of construction, durability and efficiency. The following states have the highest percentage of structurally deficient bridges as reported by the ASCE 2013 Report Card on U.S. Infrastructure. Is your state on the list? STATE NUMBER OF STRUCTURALLY % OF STATE S TOTAL DEFICIENT BRIDGES NUMBER OF BRIDGES 10. Mississippi % 9. North Dakota % 8. West Virginia % 7. Missouri % 6. Nebraska % 5. South Dakota % 4. Rhode Island % 3. Iowa % 2. Oklahoma % 1. Pennsylvania %

3 Equipment Spotlight Is It Time to Mechanize? Want to optimize productivity, save time and improve quality and safety? Consider a custom built utility/casting machine to mechanize some of your most cumbersome and laborintensive production practices. U tility/casting machines can shorten set-up time, improve safety, deliver more consistent product quality and reduce costs. Many producers have found their investment in machinery delivered a return on investment within a short time frame. Mechanization also frees workers to attend to more complex tasks. Hamilton Form builds machinery to meet individual customer needs. Machines can be designed to do one, two, or several different operations. Some producers use a machine dedicated to a single bed, especially in long-line production, while others use a machine to service multiple beds. A roller with a curing cover can also carry tarp/blanket bows. Some of the most common machines we build are blanket rollers to pay out and re-roll curing covers, but there are many cumbersome and time consuming processes that also benefit from mechanization such as: Strand pulling: A machine that rides on the form with an attachment for pulling strand can pull several strands at the same time greatly reducing set-up time. Bed prep: A machine designed with a stem or deck cleaner brush attachment to clean the casting surface makes prep quicker and helps keep forms in good condition. Form release application: A machine with a spray and mop to apply form release eliminates having to carry and handle sprayers and liquids while walking on a slippery surface. Vibration: A machine with vibrating and oscillating screeds speeds up the finishing operation. An on board air compressor to operate pneumatic vibrators can be added or built with hydraulic vibrators to eliminate the need for air. A utility machine can be built with brushes to clean the deck or stem brushes and a strand puller. Header placement: A product header cart makes handling headers easier and safer using a cart built with a deck to store and deliver headers down the bed. Lifting: A jib crane can be added to lift and position product headers or depressor beams. Mesh distribution: A deck to store and deliver mesh can be added. Machines are typically handled by one worker that rides on the machine or it can be operated with a remote control. Consider mechanizing some of your most difficult and labor intensive production processes to save time and money. Our engineering staff can work with you to design a machine to match your requirements. Give us a call at or send your request to sales@hamiltonform.com A vibrating and oscillating screed aids finishing operations.

4 Technically Speaking Designing Self-Stressing and Non-Self Stressing Forms H amilton Form builds both self-stressing and non-self-stressing, or free-standing, forms. A non-self-stressing form is designed to maintain product tolerances while resisting the hydrostatic pressure caused by the weight of the concrete in the form. Nonself-stressing forms include median barriers, copings, some box forms and wall panels that are reinforced but not pre-tensioned. We also make non-self-stressing forms for products such as bridge girders, u-beams and other heavily prestressed products. These forms are installed in stressing beds with abutments that carry the prestress load. Structural products such as double tees, beams, piling and stadia components are typically made in self-stressing forms. Self-stressing forms are designed to resist the hydrostatic force of the concrete and compressive forces introduced through prestressing. Designing a self-stressing form requires more detailed information and more time than a non-self-stressing form. To design a self-stressing form, both the maximum load and where the load is applied are used That s why both the strand pattern and maximum kips are required to design and accurately price a self-stressing form. To design a self-stressing form, both the maximum load and where the load is applied are used to determine the thickness of the skin, spacing of the gussets and the size and quantity of the longitudinal stiffeners. Forms designed to resist 900 kips have a different design and cost than a form designed for1500 kips. A form that carries the load symmetrically is designed different from a form that carries most of its load high or low. That s why we always ask for the strand pattern as well as the maximum kips in order to design and accurately price a self-stressing form. We recently quoted a casting table for a customer that provided: maximum load worse case and most common spandrel loading requirements typical height of strand placement from the casting surface of the bed the maximum strand height they may need in the future. This information allowed for a design that met their current as well as anticipated needs. You should also think about vibration and if we need to make provisions for any special curing systems. To cast a custom or specific product, we need the product drawing and how many pieces you want to cast at one time. Knowing how many pieces you want to cast at one time will provide information to determine bed length and how many headers, or bulkheads, you will need. If you intend to use this form for a single project, let us know. Hamilton Form builds forms to last. Many of our forms have been in service for twenty years or more, but if you intend to use the form for a single project, let us know and we ll look for economies in design and fabrication to better serve your needs. For DOT projects, many states require the form to withstand 10% over the designed load, while some have even more stringent requirements. In designing self-stressing forms for DOT projects, it s important that self-stressing forms comply with state requirements. Some states require the form to withstand 10% over the designed load, while some have even more stringent requirements. These requirements must be factored when designing forms for DOT projects. If you re doing DOT work, make sure we are aware of any special state requirements. Without detailed information, we can make some assumptions based on experience, but the best scenario, especially when trying to be competitive, is for us to have as much detail as possible before we design and price a form. The more details you provide; the better equipped we are to meet your needs. Calling all Cooks! The next edition of Hamilton Form s Handy Epicurean Cookbook is underway. Recipes are needed. If you or someone you know LOVES to cook please send us one or two of your favorite recipes to be included in this year s book. If you d like a cookbook, us your request, along with your recipe. Send recipes and cookbook requests to: recipes@hamiltonform.com

5 Maintenence Tips Peak Performance Q uality product is dependent on the quality of the formwork as well as the installation of the form. In addition to proper installation, don t overlook the importance of form maintenance. Periodically inspect and service your forms to make sure the forms are functioning properly. Proper installation and maintenance will help assure that product strips easily and forms last. Make form inspection part of your plant s routine maintenance program. Here are just a few inspection and maintenance recommendations from Hamilton Form: Check that the form is properly installed. Forms must be installed level and straight. Has the form been shimmed as required? Are the shims still in place? Make adjustments as needed. Long-line forms should be anchored and fixed at the center of the bed to allow for expansion and contraction in both directions, then clipped to resist uplift forces every 5 feet on centers. The clips must allow the form to move longitudinally, but at the same time, must hold the form in line. These connections should be kept clean and free of any debris and concrete build-up. Inspect vibrator mounts for any cracked welds and repair as needed. Never vibrate an empty form. Make sure jacking plates bear evenly on the end of the form skin and stiffeners. Never add new holes or enlarge existing holes in a jacking plate that will increase the stressing capacity without first checking with the engineering department at Hamilton Form. Check under the form for excessive corrosion of the under structure. Before any corrosion becomes severe, the form should be taken up, the affected areas sand blasted, and repainted. Casting surfaces should be kept clean and free of any concrete build-up. Remove debris with a wire brush or by wiping. Never sand blast or use a hard disk grinder on the skin surface. A properly level and installed form will help the product strip and produce a higher quality product. It can remove the mill scale that is the natural protective coating on the steel plate. If you are using fillers in double tee stems, they should be removed at least every 30 days. The entire leg of the double tee should be cleaned and protected from corrosion before re-installing stem fillers. Check that side rails are plumb and properly connected. Follow these and any special maintenance practices your plant may have to assure your forms are delivering peak performance. Quick Clean The fastest and easiest method of cleaning double tee stems and piling forms is with a Cleaner tm Machine from Hamilton Form. These self-propelled machines run easily on the form and keeps the cavities of tees and pilings clean to make stripping easier and keep your forms in good condition. The brush assembly can be removed and replaced with different sized brushes for use on multiple forms. For more information visit or call us at

6 Hamilton Form Company, Ltd 7009 Midway Road Fort Worth, Texas Ph Fx Employee Profile Andy Nanethasene Supervisor A ndy and his family emigrated to the U.S. from Laos in 1980 when Andy was 19 years old. For those not familiar with the geography of South Asia, Laos is wedged between Vietnam and Thailand, with Cambodia to the south and China and Burma on its northern border. Most Americans are aware of the political and economic history of that region in the 1960s and 70s. In 1975 Lao were granted refugee status and were allowed to emigrate to the U.S. When they arrived in the U.S., the Nanethasene family originally went to Arkansas. The family began learning English and quickly began acquiring job skills. Andy graduated as a certified welder and began working for Hamilton Form when the family moved to Fort Worth in Andy is still a skilled welder, although today, his role is more of a trainer and mentor to new employees. Andy has been a lead man, shift supervisor and today is a department supervisor. His positive attitude, loyalty and strong work ethic are appreciated by everyone at Hamilton Form. Andy is married and has a 14 year old son. His son is an excellent student who plays both football and soccer. Like many Asian families, maintaining strong family ties are important to the Nanethasene family. They enjoy spending time with family and especially like to camp. On many weekends, you will find them at Lake Texoma, camping, fishing and enjoying the outdoors. Andy is also an avid tennis player. You may guess that Andy is not his birth name. Thong Thanh Nanethasene proudly became an American citizen in That s when he chose his new American name Andy.