This thesis presents the results of testing to determine the significance of the group action factor at the 5% offset yield and capacity of single-shear bolted wood connections loaded parallel to grain. The single and multiple-bolt connections tested represent common connection geometries used in wood construction in the United States. The results of both monotonic and cyclic loading of connections are presented. Monotonic test data was used to determine an appropriately scaled CUREE Displacement Controlled Quasi-Static Cyclic Protocol. Overall, one hundred and eighty connections were tested using this cyclic protocol based on data obtained from thirty-three monotonic tests. Tested assemblies had geometric variables that include number of bolts per row, number of rows, bolt diameter, and side member material. In addition, the main and side member material and thickness were designed to produce three of the four major connection yield modes as defined by the 1997 National Design Specification for Wood Construction (AF&PA, 1997). Results from this research address the need for adequate spacing of bolts in a row to control the brittle connection behavior that directly affected the group action factor at capacity. / Master of Science

This thesis presents the results of testing to determine if spacing between bolts in a multiple-bolt, single-shear connection subjected to natural hazard loading affects seven strength and serviceability parameters: maximum load, failure load, E.E.P. yield load, 5% offset load, elastic stiffness, E.E.P. energy, and ductility ratio. This research also determines if a statistical difference exists between previously published research for 4D spacing as compared to results produced by this research for five alternate spacings: 8D, 7D, 6D, 5D, and 3D. Finally, this research determines which of the spacings examined: 8D, 7D, 6D, 5D, 3D; produced the most optimal results for each examined strength and serviceability parameter where optimization is based on economy and performance. Three connection configurations with five different spacings between bolts were subjected to reverse cyclic loading for a total of one hundred and fifty tests. The reverse cyclic protocol was based on recommendations by the Consortium of Universities for Research in Earthquake Engineering (CUREE) for testing woodframe structures. The same connection configurations were also subjected to monotonic loading for an additional forty-five tests. Results of this research can be used to evaluate the current design recommendation presented in the National Design Specification (NDS) for Wood Construction (AF&PA, 2001) of spacing bolts at four times the bolt diameter (4D) to determine if a different spacing should be recommended for natural hazard loading conditions. / Master of Science