Evaluation of Sugi Finger-jointed Laminae with a Knot and Starved Joints by Acoustic Emission
スポンサーリンク
概要
- 論文の詳細を見る
In the manufacture of glulam timbers, the laminae that have knots near the finger-joint and starved part in the finger-joint are often found, and it will greatly influence the decrease in strength of products. Therefore, the detection of knots and starved joints is important for preparation of laminae, and the method is hoped to be simple and non.destructive. In this study, sugi (Cryptomeria japonica D. Don) finger-jointed laminae with an intergrown knot near the finger-joint and starved joints in the finger-joint were prepared, and the evaluation of finger-joint performance was conducted by acoustic emission (AE) as the non-destructive method. That is, bending tests for these laminae were performed, and AE generated during bending test was measured along with load. Then, the correspondence between AE characteristics and the strength properties was examined. The main results are summarized as follows: for the laminae with a knot parallel to the finger-joint and starved joints in the finger-joints, AE signals were measured at the early stage of the bending test and the accumulated AE count was large as compared with the laminae without knots and starved joints/controls. Therefore, the AE technique is promising for the monitoring of knots and starved joints during bending test. In this experiment, for the laminae with a knot, the difference of the bending strength was not admitted. From this result, the bending strength was almost unaffected by the difference of the knot position near finger-joint. For the laminae with starved-joints, the MOE was almost unaffected by the presence of the starved joints, while the MOR decreased slightly as compared with the controls. It follows from the above results that the AE technique is promising for the detection of knot parallel to the finger-joint and starved joints in the finger-joint at the early stage of the bending test, even if the knot and starved joints do not cause much reduction in the bending strength.
- 九州大学の論文
著者
-
Morita Hideki
Miyazaki Prefectural Wood Utilization Research Center
-
OHUCHI Takeshi
Faculty of Agriculture, Kyushu University
-
MURASE Yasuhide
Faculty of Agriculture, Kyushu University
-
FUJIMOTO Yoshiyasu
Miyazaki Prefectural Wood Utilization Research Center
-
Ohuchi Takeshi
Faculty Of Agriculture Kyushu University
-
YANO Kiyoko
Faculty of Agriculture, Kyushu University
-
Yano Kiyoko
Faculty Of Agriculture Kyushu University
-
Murase Yasuhide
Faculty Of Agriculture Kyushu University
-
Ouchi Takeshi
Faculty of Agriculture, Kyushu University
関連論文
- Analysis of Combustion Emissions and Char from CCA- and ACQ-Treated Wood
- Application of Bamboo Vinegar with Process to Evaluate Fungi Resistance of Bamboo Materials
- Influences of Particle Size and Moisture Content on Ultrasonic Wave Transmission Characteristics in Thickness Direction of Particleboard
- Acoustic Emission Generation at Fracture Point During Tensile Tests in the Thickness Direction of Particleboard : Effects of the Board's Internal Structure
- Application of TGA and EDX Analysis to Evaluate the Process of Preservative-Treated Woods
- Studies on Axial Deviation of Hole in Deep Machine-Boring of Wood
- Manufacturing Flame-Retardant Panels from Japanese Cedar by the Pressure Process Combined with Hot Pressing Techniques
- Development of an Automatic Detection System for Knots Appearing on the Surface of Sugi Laminae with a Two-Dimensional Three-Charge Couple Device Color Camera
- Studies on Life Cycle Assessment of Sugi Lumber
- Milling of wood and wood-based materials with a computerized numerically controlled router V : development of adaptive control grooving system corresponding to progression of tool wear
- Evaluation of Sugi Finger-jointed Laminae with a Knot and Starved Joints by Acoustic Emission
- Cross-sectional cutting of bamboo with a pair of shearing blades for bamboo cube production
- Milling of wood and wood-based materials with a computerized numerically controlled router IV : development of automatic measurement system for cutting edge profile of throw-away type straight bit
- Corrosive-wear characteristics of diamond-coated cemented carbide tools
- Bending creep of glued laminated timber (glulam) using sugi (Cryptomeria japonica) laminae with extremely low Young's modulus for the inner layers