Concrete-filled composite plate shear walls (C-PSW/CFs, also known as SpeedCore) combine steel plates and concrete infills to accelerate construction schedules by eliminating formwork and reinforcement congestion. Bolted splices can be used for the splice connection between C-PSW/CF panels; because of the ease of installation, inspection, and approval of such connections, the use of bolted splices leads to faster construction schedules compared with traditional complete joint penetration field welds. That said, there are some design limitations for these connections when accounting for seismic load combinations, as they often use unconventional fasteners whose shear force is not well documented. New research from Shivam Sharma, Soheil Shafaei, Amit Varma, and Ron Klemencic offers novel methods to estimate the fundamental response, flexural capacity, and ultimate rotation of bolted splice connections for C-PSW/CFs.
Their study, “Behavior and Design of Bolted Splice Connections for C-PSW/CF Walls,” involved evaluating prior large-scale experimental testing using bolted splices, developing 3D models, formulating a component-based model for blind bolts, and extending the instantaneous center of rotation method. This research is vital to the structural engineering profession because bolted splices drastically speed up construction but their seismic and lateral load behaviors, the fastener shear force, and the complex contributions of concrete infill must be accurately quantified to ensure safe high-rise building design. Learn more about this research and how it can enhance both the initial shear stiffness and capacity of blind bolts in the Journal of Structural Engineering at https://ascelibrary.org/doi/10.1061/JSENDH.STENG-15359. The abstract is below.
Abstract
This paper briefly summarizes the results from experimental and numerical investigations conducted on full-scale planar concrete-filled composite plate shear walls (C-PSW/CF) with bolted splice connections. These experimental results and numerical models are used to develop and verify design methods for estimating the moment capacity (๐๐) and ultimate rotation (๐๐ข) of bolted splice connections using the instantaneous center of rotation method (ICM) and a less accurate but simpler method (SM). The shear force – deformation relationship for fasteners (blind bolts and threaded rods in sleeves) and the beneficial effect of concrete are incorporated into the design methods. These shear force – deformation relationships and component-based models for fasteners (blind bolts in particular) are developed and validated using corresponding fastener test results and numerical models. The experimental and numerical results from the planar C-PSW/CF walls are used to extract and validate the fundamental moment–rotation (๐-๐) relationships for bolted splice connections. These relationships are then used to develop and validate an empirical model for the ๐-๐ relationship of bolted splice connections. These models utilize the moment capacity (๐๐) and ultimate rotation (๐๐ข) calculated using the design methods (ICM or SM) or numerical models of the connections. The effects of connection flexibility (i.e., ๐-๐ relationship) on the lateral stiffness of the overall C-PSW/CF wall system are evaluated, and design recommendations for limiting the reduction in lateral stiffness of the system are proposed.
Learn more about the effectiveness of bolted splice connection fasteners and how to use them in your own SpeedCore installations in the ASCE Library: https://ascelibrary.org/doi/10.1061/JSENDH.STENG-15359.
