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CFRP repairs precast damage caused by temperature differential
Structural Preservation Systems strengthens parking deck
Precast concrete double-tees and joists are a common feature on many parking decks. While the use of these materials is proven for parking deck construction, several owners have noticed that the prestressed framing members on the top level would begin to camber. While the temperature remains fairly constant for the lower portions of the structure, the joists on the top level are directly exposed to the sun and therefore experience large temperature swings. This process can create stress on the structure, causing cracking and spalling. In response to this scenario, two common repair strategies have emerged to combat this challenge: the use of carbon fiber reinforced polymers (CFRP) to strengthen the structure and/or the installation of supplemental joist hangers.