Mechanical Engineering Commons^™

Reliability Indices For Bolted And Nailed Connections In Wood Structures, David Pollock, Donald A. Bender

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

Recently published test data for bolted and nailed connections was evaluated to assess the structural reliability inherent in current allowable stress design procedures for connections in wood structures. Reliability indices were determined for timber connections using standard firstorder, second moment (FOSM) procedures. For the connections considered in this study, reliability indices range from 2.6 to5.1, generally providing higher levels of safety than the structural members in timber structures.

Bolt Bearing Behavior Of Engineered Wood Composites, Stephen J. Carstens, David Pollock

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

The goal of this research was to gain a better understanding of the bolt bearing behavior of engineered wood composites made from yellow poplar lumber. Lumber specimens included in this study were laminated veneer lumber, strandbased lumber, yellow poplar lumber, and Douglas-fir larch lumber. Testing followed the half-hole and full-hole configuration as set forth in ASTM Standard D5764 (1998).

In a previous study by Wilkinson (1991), a strong correlation was shown between bearing strength perpendicular to grain and bolt diameter. This study supports Wilkinson's finding for bearing strength perpendicular-to-grain based on the half hole test configuration. Other findings in this …

Ultrasonic Detection Of A Plastic Hinge In Bolted Timber Connections, David Pollock, Donald A. Bender, Don E. Bray, James T P Yao

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

Connections between structural members are critical elements that typically govern the performance of structural systems; hence, techniques for monitoring the condition of connections are needed to provide early warning of structural damage. Plastic hinge formation in fasteners frequently occurs in timber connections when the yield capacity is exceeded. An innovative pulse echo testing technique was developed for detecting the formation of a plastic hinge in bolted timber connections and estimating the associated magnitude of connection displacement. A shift in overall signal centroid proved to be the best flTedictor of plastic hinge formation, with a coefficient of determination (R2) of 0.9. …