{"@context":{"@vocab":"https://cir.nii.ac.jp/schema/1.0/","rdfs":"http://www.w3.org/2000/01/rdf-schema#","dc":"http://purl.org/dc/elements/1.1/","dcterms":"http://purl.org/dc/terms/","foaf":"http://xmlns.com/foaf/0.1/","prism":"http://prismstandard.org/namespaces/basic/2.0/","cinii":"http://ci.nii.ac.jp/ns/1.0/","datacite":"https://schema.datacite.org/meta/kernel-4/","ndl":"http://ndl.go.jp/dcndl/terms/","jpcoar":"https://github.com/JPCOAR/schema/blob/master/2.0/"},"@id":"https://cir.nii.ac.jp/crid/1050845763851992832.json","@type":"Article","productIdentifier":[{"identifier":{"@type":"HDL","@value":"http://hdl.handle.net/10091/14067"}},{"identifier":{"@type":"URI","@value":"https://soar-ir.repo.nii.ac.jp/records/11195"}},{"identifier":{"@type":"NDL_BIB_ID","@value":"5290502"}},{"identifier":{"@type":"URI","@value":"http://id.ndl.go.jp/bib/5290502"}},{"identifier":{"@type":"URI","@value":"https://ndlsearch.ndl.go.jp/books/R000000004-I5290502"}},{"identifier":{"@type":"NAID","@value":"110000237354"}}],"resourceType":"紀要論文(departmental bulletin paper)","dc:title":[{"@language":"ja","@value":"信州産カラマツ実大材の強度評価の寸法効果と機械等級区分"},{"@language":"en","@value":"Size Effects on Strength Evaluation and Mechanical Grading in Japanese Larch Lumber from Shinshu"},{"@language":"ja-Kana","@value":"シンシュウサン カラマツ ジツダイザイ ノ キョウド ヒョウカ ノ スンポウ コウカ ト キカイ トウキュウ クブン"}],"dc:language":"ja","description":[{"type":"Abstract","notation":[{"@value":"The report was reconstructed from a series of the individual investigations on mechanical properties of Japanese larch (Larix kaempferi, Carriere) lumber, and it consists of the following five sections. 1. Introduction Japanese larch is one of the most important species in Shinshu (Nagano prefecture) as stock of the planted forests, and it has been increasingly expected for practical use as structural wood products. Thus, it is necessary to evaluate more precisely strength properties of Japanese larch lumber now. The principles of reliability-based design have been introduced to alter the code for timber structures in the developed countries. In the case, reliability calculations depend on the lower tail of the strength distribution, and it means that there will be small potentiality of the lumber without knowing the lower tail in the future. It is important to implement the true structural behavior of timber, and size effect is one of the chief concern of many researchers after 1990's. Then I focussed on the dependency of strength distribution on Young's modulus in Japanese larch lumber. Experimental works were done, and some suggestions on strength evaluation were presented. 2. The Fifth Percentile Estimate of Bending, Longitudinal Compressive, and Tensile Strengths of Square Sawn Larch Timbers from Shinshu. To investigate the mechanical properties of Japanese Larch square sawn timbers, bending, longitudinal compressive, and tensile tests were conducted. Sawn timbers for specimens were processed from 72 trees from seven stands in Shinshu. Specimen dimensions of cross-sections were nominal 12 cm × 12 cm. First, normal distribution, log-normal distribution and 2P-Weibull fit to bending, compressive, and tensile strength data in order to estimate the fifth percentile values. In the case of the 2P-Weibull, it fits to all data and to the lower tail 15% data. The results indicated that the values obtained from each distribution were almost equal to non-parametric estimates (NPE) in compression, but the values from log-normal and 2P-Weibull fits to the lower 15% data were near the NPE in bending and tension. Then, the distributions of the strengths of specimens classified by modulus of elasticity (MOE) were different in bending, compression, and tension. In the case of tension, there were small differences between the distributions of strengths of the low-grade specimens and the medium-grade specimens. From the distributions of the averages of MOE classified by strengths, it was shown that we may be analyzing experimental data as one group of lower 15% data in bending and the lower 50% data in tension. [Takeda T, Tokumoto M, Nakano T, Hashizume T, Nagao H (1998) Mokuzai Gakkaishi 44 : 170-177] 3. Effect of Number of Laminae on Mechanical Properties of Glued Laminated Timber Composed of Homogeneous-Grade Lumbers of Japanese Larch 3.1 Effect of Number of Laminae on Dynamic MOE of Glued Laminated Timber Composed of Homogeneous-Grade MSR Lumbers of Japanese Larch The tapping method to measure the Young's modulus of wood is useful for nondestructive evaluation of sawn lumbers. The dynamic MOE values are calculated from the resonance frequency of the tap tone with a FFT spectrum analyzer. However, if a glulam is used for a bending member such as a beam, it is not certain that the static MOE value of the glulam is equal to the dynamic MOE value. In case of glulams composed of sawn lumbers from juvenile wood, some adjustment to the dynamic MOE values may be necessary for use. Then the relationship between static MOE (E_s) and dynamic MOE(E_d) was investigated, since it was expected that the variation of MOE in the cross section of homogeneous-grade glulams would be relatively small. Two types of specimens were used: glulams laminated horizontally (H-type) and vertically (V-type). Dynamic MOE was measured by longitudinal vibration(E_l) and flexural vibration, whose directions of which were horizontal(E_h) and vertical(E_v) in the direction of the adhesive face of the glulam. The results indicated that E_h/E_s in H-type and E_v/E_s in V-type were not influenced by the number of laminae. As it was supposed that E_l/E_h should be influenced by the number of laminae, the relationship between E_l and Eh was estimated by simple simulation for different numbers of laminae. The estimated ratios of E_l, E_h and E_v to E_s were almost identical with the experimental data. [Takeda T, Hashizume T (1997) J Soc Mater Sci 46 : 839-844] 3.2 Properties of Compressive Strength Parallel to the Grain of Structural Glued Laminated Timber Composed of Homogeneous-Grade Lumbers of Japanese Larch It is known that bending strengths of glued laminated beams (glulams) may be dominated by tensile strengths of outer layers of glulams. Since compressive strengths as well as tensile strengths of laminae should effect the stress distribution through the depth of the beam, the compressive strength may be important to estimate the bending strength of the  ..."}]},{"type":"Other","notation":[{"@value":"Article"}]},{"type":"Other","notation":[{"@value":"信州大学農学部演習林報告 36: 21-81(2000)"}]}],"creator":[{"@id":"https://cir.nii.ac.jp/crid/1070845763851992832","@type":"Researcher","foaf:name":[{"@value":"武田,  孝志"}]}],"publication":{"publicationIdentifier":[{"@type":"ISSN","@value":"05598613"},{"@type":"NDL_BIB_ID","@value":"000000012113"},{"@type":"LISSN","@value":"05598613"},{"@type":"NCID","@value":"AN00121330"}],"prism:publicationName":[{"@value":"信州大学農学部演習林報告"}],"dc:publisher":[{"@value":"信州大学農学部附属演習林"}],"prism:publicationDate":"2000-03-01","prism:volume":"36","prism:startingPage":"21","prism:endingPage":"81"},"url":[{"@id":"https://soar-ir.repo.nii.ac.jp/records/11195"},{"@id":"http://id.ndl.go.jp/bib/5290502"},{"@id":"https://ndlsearch.ndl.go.jp/books/R000000004-I5290502"},{"@id":"http://hdl.handle.net/10091/14067"}],"dataSourceIdentifier":[{"@type":"IRDB","@value":"oai:irdb.nii.ac.jp:00990:0001374592"},{"@type":"NDL_SEARCH","@value":"oai:ndlsearch.ndl.go.jp:R000000004-I5290502"},{"@type":"CIA","@value":"110000237354"}]}