Crack Control Measures for Tilt-Up Concrete Panels

Joe Steinbicker, P.E., S.E. (joes@ssa engineers.com), is a charter member and past chairman of ACI Committee 551, Tilt Up Concrete Construction. He is also a founding member of the Tilt Up Concrete Association and past member of their Board of Directors. By John Lawson P.E., S.E. and Joe Steinbicker P.E., S.E. Crack Control Measures for Tilt-Up Concrete Panels W hen it comes to enclosing large building volumes, it is hard to beat tilt-up concrete construction for economy and durability. Long considered the mainstay for warehouses and big-box retail, the tilt-up method is now frequently employed for commercial projects, churches, schools and Class A office buildings nationwide. With newer types of occupancies driving attention to aesthetics higher and higher, the importance of minimizing concrete cracking in the site-cast precast wall panels is greater than ever. Tilt-up concrete construction incorporates concrete wall panels that are formed, cast and cured on a ground supported slab at the building site and then tilted into place, one large panel at a time. The individual wall panels are erected around the building’s perimeter, separated by vertical joints. Single story occupancies are still most common; however, many buildings are now multiple stories. While many of the features of tilt-up panel construction tend to reduce the potential for developing cracks when compared to conventional concrete construction, the unique method of how the buildings are constructed still requires some special considerations for controlling cracking. The lifting and setting of wall panels, as well as the effects of restrained drying shrinkage, are important items to address to minimize potential wall cracking.