Seismic Performance of Full-Scale Moment Connections of One-Story Precast Industrial Facilities

One-story concrete moment frame buildings present critical joints because free horizontal faces reduce their confinement in the core, affecting the anchorage of the top beam reinforcement and producing joint distress. In addition, precast concrete processes that involve prestressed beams with different shapes, precast concrete columns, construction of joints on the jobsite, and special construction details such as a reinforced topping on top of the beam joints could affect the seismic performance of one-story precast moment frames for industrial buildings. Due to the lack of experimental testing, six full-scale critical connections were cyclically tested to allow understanding of their seismic performance. Test specimens include one precast reinforced column, three knee joints, and two interior joint sub-assemblages that were designed based on ACI 318. All connections sustained at least a 3.5% drift ratio with no beam longitudinal reinforcement bar rupture or buckling and very low or no observed damage of the column and minimal joint distress, which is consistent with the strong-column/weakbeam design philosophy. The performance acceptance criteria of ACI 374.1 was satisfied by all test specimens in terms of stiffness, strength, and energy dissipation. Nonetheless, the presence of the reinforced topping slab on the top of the joint plays a role in achieving slightly better strength, ductility, and hysteretic performance response.