The objective of this paper is to present the effect of floor-to-wall connection details on ledger framing performance for light-framed cold-formed steel construction. The possibility of alternative lateral load paths to current seismic design, which assumes load flows to and through only shear walls was observed in recent full-scale shake table tests on a two-story cold-formed steel building where ledger framing was a key feature. The building exceeded predictions based on sub-system level design. One hypothesis is that joist-to-ledger connections contributed to the lateral load resisting system. The tests conducted here aim to quantify the strength and stiffness of the joist-to-ledger connection so that this hypothesis may be explored further. Current design for these connections is based on screw shear. However, test results indicate that newly observed limit states such as ledger flange buckling and stud web crippling drive joist-to-ledger connection moment-rotation response. The experimental program was designed to evaluate the clip angle location (inside or outside of the joist section) and presence of top and bottom screws connecting joist and ledger flanges depending on joist location relative to studs (mid studs, close, and on stud). These tests are a part of a broader experimental study on ledger framing construction to support future 3D seismic building analysis and design for cold-formed steel construction.
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