Moisture Content and the Properties of Lodgepole Pine Logs in Bending and Compression Parallel to the Grain

摘要

This study evaluates the effect of moisture content on the properties of 127- to 152.4-mm (5- to 6-in.-) diameter lodgepole pine (Pinus contorta Engelm.) logs that were tested either in bending or in compression parallel to the grain. Lodgepole pine logs were obtained from a dense stand near Seeley Lake, Montana, and sorted into four piles of 30 logs each. Two groups were tested in bending, one green and one dry, and two in compression parallel to the grain. The results of the study provide conservative procedures for estimating compression strength for green logs based on the assigned bending strength and show that modulus of elasticity determined by transverse vibration (Ety) on green logs is a conservative estimate of Ety for dry logs. Experimental problems with conditioning the logs tested in bending produced inconsistencies in some property relationships. A more comprehensive study, already in progress, should help resolve the questions raised by these inconsistencies.