Wind and Seismic Behavior of Noncontact Lap-Splice Connections for Concrete-Filled Composite-Plate Shear Walls

Concrete-filled composite-plate shear walls (C-PSW/CFs), or SpeedCore walls, have to be anchored to the reinforced concrete foundation or base. Different wall-to-base connection types have been considered, but noncontact lap-splice connections between dowel bars extending from the concrete base and embedded within the concrete infill of C-PSW/CFs are of significant interest due to their advantages of constructability, efficiency, and familiarity. This noncontact lap-splice connection governs the lateral load resistance of the composite wall system. It can be implemented for wind loading governed conditions, and depending on performance (ductility) may also be adequate for seismic loading conditions. This paper presents the results of experimental investigations conducted to evaluate the wind and seismic performance of these noncontact lap-splice connections. A cyclic loading protocol representative of wind and seismic loading was used to conduct the tests. Three large-scale specimens with different connection details were designed, fabricated, and tested to failure. The effect of wind loading cycles on the lateral stiffness of the connections was evaluated. The specimens had linear elastic response during the elastic wind cycles and minimal loss in the stiffness during the inelastic wind cycles. During the seismic cycles, the specimens developed plastic hinges and exhibited significant ductility before failure due to tensile rupture of dowel rebars. Numerical models were developed, validated, and analyzed to gain insights into the connection behavior. These models indicated extensive yielding of the dowel rebars and accurately captured nonlinear behavior, making them suitable for future parametric studies.