Investigation of the Procedure for Estimating Concomitance of Lumber Strength Properties
Keywords:Correlation coefficient, concomitance, bending strength, tensile strength, computer simulation
AbstractAn analytical method that utilizes information generated through proofloading to estimate the correlation between lumber strength properties is reviewed. A computer simulation was conducted to determine the effects of sample size and proofload level and also the degree of true correlation between lumber properties on the estimates of the correlation coefficient. Results indicate that reasonable estimates of the correlation coefficient can be obtained using sample sizes of 100 or more with a minimum proofload that would be expected to break 40% (proofload level = 0.40) of the specimens tested. Additional studies are suggested, however, before the technique is used.
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