The pre-cut lumber industry is a critical node in the distribution of lumber for construction and plays a significant role in driving demand for wooden products. However, it is categorized under the miscellaneous wooden products sector in the existing national input-output table (ex-IO) at present. In this study, based on mail surveys, interviews, and statistical data, we developed an extended input-output table suitable for analyzing wood use by establishing a pre-cut lumber sector and a new miscellaneous wooden products sector (new-WP) within the ex-IO framework. As a result, most of the input in the pre-cut lumber sector was lumber, and the ratio of gross value added accounted for 34.4% of total input. On the other hand, the input of the new-WP was diverse and not limited to lumber, and the ratio of gross value added accounted for 59.1% of total input. It shows that mechanization or automation in the pre-cut lumber industry had advanced like other lumber industries.

In drift-pin joints with slotted-in steel plates, a staggered arrangement of drift pins can potentially reduce the joint size. Sufficient staggered widths and fastener spacings that prevent brittle behavior under shear loading must be clarified. In this study, a double-shear test was conducted under various staggered arrangements of drift pins, primarily focusing on the ductility. Ductile behavior was observed when the fastener spacing was six times the fastener diameter or greater. Furthermore, brittle behavior was observed at five times the diameter under conditions with small staggered widths. When the spacing was 3.5 times, all the configurations exhibited brittle behavior regardless of the staggered width. Additionally, an attempt was made to numerically express the arrangement conditions using ellipses in a planar coordinate system, and a simplified method was proposed to ensure the deformation performance. These findings are valuable for joint designs.

In wooden structures, when imparting load-carrying capacity and ductility to joints using bending-yielding fasteners, an appropriate arrangement of fasteners is required. While specifications for fastener arrangement have been proposed for joints using sawn lumber and glued-laminated timber or Cross-Laminated Timber, there is no knowledge regarding whether these specifications can be directly applied to Multi-layered Plywood (MLP) joints. Therefore, this study investigated the effects of fastener arrangement and spacing on the load-carrying capacity and ductility of MLP joints composed of two fasteners, with the face veneer grain direction aligned with the loading direction. The results indicated the necessity of ensuring a fastener spacing of at least five times the fastener diameter (5d, where d is the fastener diameter) when two fasteners are placed in a single row parallel to the loading direction when the end distance is equal to or greater than 5d. When two fasteners were arranged in a single row perpendicular to the loading direction, it was indicated that the fastener spacing should be at least 5d (with an end distance of 5d) or at least 3d (with an end distance of 7d). These findings indicate that MLP joints should have different fastener arrangement specifications compared to existing ones.

When multiple fasteners are arranged in a single row parallel to the grain in a connection using bending-yielding fasteners in wooden structures, the connection's load-carrying capacity is not simply equal to the sum of the individual fastener capacities, but is assumed to be multiplied by a reduction coefficient. Currently, reduction coefficients are proposed only for connections arranged in a single row parallel to the grain. Given that Multi-layered Plywood (MLP) has different material properties compared to sawn lumber and glued laminated timber or Cross-Laminated Timber, it is unclear whether the existing reduction coefficients can be directly applied to MLP connections. Furthermore, MLP connections may possess unique reduction coefficients that differ from existing standards. While existing standards define reduction coefficients based on linear fastener arrangements, it is anticipated that fasteners will also be arranged in matrices in MLP connections. Therefore, it is necessary to establish reduction coefficients for such configurations. Knowledge on reduction coefficients has been accumulated in this study by examining the results of experiments with 4 or 6 fasteners arranged in both linear and matrix configurations. Consequently, it has been confirmed that the reduction coefficients for the specific configurations tested in this research are 1.0.

The authors are involved in the standardization of the JAS method that will enable sawmillers and builders to determine the content of functional low-molecular components in dried solid cedar wood, in order to further evoke the demand for domestic cedar wood (Cryptomeria japonica). The solvent extraction-gas chromatography-mass spectrometry (GC-MS) method developed by the authors can clarify the content of sesquiterpenes, which are thought to contribute to the functional properties of cedar wood (such as improved sleep quality, relaxation, antibacterial and anti-mite effects). In this paper, the validity of the method was confirmed in a single laboratory according to international guidelines. The evaluation parameters were selectivity, lower limit of detection, lower limit of quantification, calibration curve, accuracy (recovery rate) and precision (concurrency, intermediate precision). Results for recovery rate and accuracy were obtained. Peak resolution, linearity of the calibration curve and lower limits of detection and quantification were also confirmed, and were judged to be valid analytical method.