Potential Of Strength Grading Of Timber With Combined Measurement Techniques A Study On The Combigrade Project-phase 2

The idea of this project is that some samples of timber are tested by some nondestructive methods one by one, which will supply a good start for the evaluation of timber strength.This study aims at the research on potential of strength grading of timber with combined measurement techniques.In this project, two species including Spruce and Pine from five areas in Finland and Russia , are made into 4.5 meters length of pecies with five different crosection , in all 2000 pieces, which are measurd by log-test, and some nondestructive tests ,visual test ,destructive test. "Grade determing properties"are gotten by all testing , based on which digital grading for timber is made according to three cretia including two Nordic rules and one Chinese standard.Finally in order to find better combined measurement methods, correlation between all test methods and destructive test should be analysied.Only for the analysis of these test methods on this paper, the result is: the correlation between combing BoardMOE.fibergen with all knot parameters and MOR is best , and the second is the correlation between combining BoardMOE.fibergen with LKAR in visual measurement and MOR. The difference of above two combination methods is not big, but both have apparent difference to others. In addition any combination with density can give a rise to the efficiency of any individual measurement.