Mechanical performance and contact zone of timber joint with oblique faces

0446321 - ÚTAM 2016 RIV CZ eng J - Journal Article
Kunecký, Jiří - Sebera, V. - Tippner, J. - Hasníková, Hana - Kloiber, Michal - Arciszewska-Kędzior, Anna - Milch, J.
Mechanical performance and contact zone of timber joint with oblique faces.
Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis. Roč. 63, č. 4 (2015), s. 1153-1159. ISSN 1211-8516. E-ISSN 2464-8310
R&D Projects: GA MK(CZ) DF12P01OVV004
Keywords : bending * contact zone * digital image correlation * dowel * non-destructive testing * timber joint
Subject RIV: AL - Art, Architecture, Cultural Heritage
http://dx.doi.org/10.11118/actaun201563041153

The goal of the work was to evaluate mechanical performance of full-scale timber beams containing scarf joint with a dowel. Work focused on standard testing using modular system to obtain eff ective stiff ness and strength of the beams with and without the joint. The work further researched a contact zone between two timber parts of the joint – at the scarf face. This was carried out using non-destructive optical technique – digital image correlation (DIC) and newly developed algorithm. The joint was made of Norway spruce, dims. 6×0.2×0.24 m and was loaded by two modes: a) 3-point bending and b) 4-point bending. During the loading, a sequence of images was acquired for further investigation of contact zone using the proposed algorithm. The joint with scarf and dowel provided enough eff ective stiff ness, ie. 73–93% for 3-point bending test and 71% for 4-point bending with respect to MOE measured on reference solid beams. Eff ective strength of the joint was also relatively high and in a range of 55% and 60% with respect to reference solid beams in both 3-point and 4-point bending tests. Contact length diff ered for loading modes. Mean contact length in symmetrical 4-point bending was about 40%, for asymmetrical 3-point bending test, it was approx. 20% on face closer to support and 44% on a face closer to loads.
Permanent Link: http://hdl.handle.net/11104/0248310