Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)


Agricultural Engineering


This study was designed to investigate the effect of cyclic moisture changes on the strength of three member nailed wood joints. The construction material used consisted of Douglas fir construction grade 2-inch by 4-inch main members and splice plates of 3/8-inch and 5/8-inch exterior Douglas fir plywood. Nails were placed in single shear and double shear with the two sizes of splice plates. Nail sizes were 6d bright common, 8d bright common, and 8d bright ring shank. Specimens with various combinations of splice plate thickness and nail sizes were constructed with single shear and double shear being considered. The specimens were separated into two series: constant moisture series and cycling moisture series. A statistical analysis was performed on the observed data in two phases: (a) an estimating equation, standard deviation, standard error of estimate, unexplained variation, explained variation, and coefficient of correlation were determined for load versus time, (b) the results of the first analysis indicated “pooling” of data in groups was possible, therefore a t-test and an analysis of variance was performed on the means of the cycling and constant moisture series to indicated whether or not a significant difference existed between the two series.

Library of Congress Subject Headings

Nails and spikes


Includes bibliographical references



Number of Pages