NONDESTRUCTIVE EVALUATION OF MECHANICAL STRENGTH OF SARAWAK TIMBERS

摘要

An acceptable method of estimating timber strength has to be established to develop confidence in using timber as construction material. In this study, six methods of measuring modulus of elasticity viz., E_(fr), E_(usw), E_(dwf), E_(dwe), E_(app) and E_(tru) were compared and used to predict the bending strength of structural size timber. A total of five-timber species viz., Parashorea macrophlla, Gonystylus bancanus, Shorea albida, Dipterocarpus rigidus and Cotylelobium burckii were used in this study. The coefficient of correlation between E_(fr), E_(usw), E_(dwf), E_(dwe), E_(app) and E_(tru), and MOR were obtained. It was found that the six moduli of elasticity could be used as a parameter to predict the bending strength of 50 mm by 100 mm structural size timber tested at air-dried condition. Amongst the methods used, E_(fr) was found to be more reliable, easy and convenient to use.