Effect of shape of test specimen on the shear strength of bamboo from eastern region of sumatera utara

Abstract

Wood is the most common forest-based product used in the construction industry, but due to reducing area of forest in the world, substitution materials for wood are needed. Bamboo has a huge prospect for the future as a wood substitute, and extensive and continuous research of bamboo, especially in mechanical properties of bamboo must be carried out to support bamboo as a material substitution for woods. This research focused on the shear strength of bamboo by comparing two types of standard tests used to determine the shear strength of bamboo. The standards are ISO 22517 and ASTM D 143. The compression test to determine the compressive strength is also conducted in this research. The bamboo species that used in this research are the species that grow in various district in the eastern region of Sumatera Utara. The result of the test shows that the highest shear strength for the specimens tested by ISO 22157 standard is Bambusa vulgaris with 6.32 MPa from Asahan and Tanjung Balai, and for the specimens tested by ASTM D 143 standard is Bambusa vulgaris with 12.31 MPa from Batubara. From the result it can be seen that all samples tested with ASTM D 143 standard have higher shear strength than those who tested with ISO 22157, with conversion ratio of 0,63. For compression test, the highest compressive strength is Gigantochloa robusta with 65.41 MPa from Asahan and Tanjung Balai.