img-stru-chmnysDelta Structural Technology Inc. was brought in to restore and preserve three historical chimneys in San Antonio, Texas. These chimneys were approximately 204 ft high, and 18 ft diameter at the base and, 15 ft diameter at the top. These structures had previously been retrofitted with steel bands every 20 ft. from top to bottom. The steel bands had either severely corroded and fallen off or had relaxed to the point that they were providing little, if any, structural confinement. Delta Structural Technology LLC. completely retrofitted all three stacks using high strength Composite Fiber System developed by groups like Fyfe Co. and Sika Corp. The installation took less than two months. The Glass Fiber Composite System was designed to provide confinement in concrete and water proofing the surface. The project received the American Concrete Institute Texas Project of the Year. A real estate development company purchased the old Alamo Cement Manufacturing facility in San Antonio, Texas for redevelopment into a unique shopping center. Paramount to the property is the existing four chimneys that were part of the fire kilns used to produce cement. Three of the stacks were built shortly after the turn of the 20th century and over the years had corroded and deteriorated to the point that pieces of the structure were falling off. . Delta Structural Technology was contracted to assist in the design of the concrete repair and the application of the composite wrap as a waterproofing member and an external structural strengthening member.

The general contractor installed an elevator lift system that covered all three stacks and allowed the work to progress from the structural concrete repair at the top, infilling of the cracks in the concrete, and application of the wrap. A polyurethane coating was applied over the wrap for protection against ultra violet sunlight damage. The project was the American Concrete Institute San Antonio project of the year for 1997.