FEATURE COPANO BAY BRIDGE Initial castings revealed some small crazing
cracks in the top of the pile at intermittent locations. "The question was, what caused the crazing?" said Malaer, "Was it shrinkage, form movement, mix design or some combi- nation?" After looking at several scenarios, Valley tried covering the beds with insulated curing blankets, supplied by Hamilton Form, which solved the problem, explained Malaer. Once TxDOT approved the test piles, Valley was ready to go into full production. "When adding new equipment in a precast
plant," said Malaer, "it's smart to choose a supplier you can trust and is experienced. Over the years, we've worked with Hamilton Form on a number of projects. They're true partners—experienced, reliable and fair." The success of any formwork package is the ability to integrate form design with produc- tion practices; in this case, it was critical. The collaboration between Valley Prestress and Hamilton Form led to a broad and com- prehensive understanding of the production challenges that needed to be solved. That collaboration was the key to the success of this project, and now Valley Prestress is in the midst of producing 460, 54-in., cylindri- cal piles for the project, located about 160 miles from the precast plant.
Valley Prestress worked with Hamilton Form to design the formwork package for this project. With a 54-in. outside diameter and 42-in. collapsible voided center, the forms were made in multiple segments to allow them to be set up and broken down in stages. The void and roller assembly (pic- tured here), and the finished piles were moved into the yard using a Mi-Jack gantry crane.
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