Strength and Stiffness Characteristics of Typical Exposed Base Plate Connections Using Parametric Finite Element Modeling

摘要

The cyclic behavior of baseplate connections has long been recognized to play an important role in the seismic behavior of buildings, non-building structures, and nonstructural components. However, the actual cyclic behavior of these connections is often grossly simplified in both static and dynamic analysis as either a fully pinned or fully fixed boundary condition. This approach may lead to over-conservative designs or under-prediction of drifts and other demands, depending on the actual behavior of the connection. A commonly cited reason for this simplistic approach is the sophistication and cost required to fully model these connections using finite-element techniques. This paper presents preliminary results from a semi-automated approach for performing parametric numerical analyses. The method provides estimates of the initial stiffness, secant yield stiffness, ultimate strength, and rotation capacity considering a variety of common baseplate and anchor configurations. These values are essential for designers performing hand calculations or as input to global structural models. The numerical model presented has undergone preliminary verification using results from recent full-scale testing, and utilizes material properties from commonly used anchor types and grades.