Pub Date : 2024-02-10DOI: 10.1186/s10086-024-02125-5
Xiaoyue Gao, Qing Chun, Yidan Han
Traditional timber buildings are sensitive to wind action. Studying the wind pressure characteristics is the premise for the preventive conservation of traditional timber buildings. To investigate the computational fluid dynamics (CFD) numerical simulation method for wind pressure on traditional timber buildings, a typical traditional timber building, the main hall of Shisi Temple, is chosen as a case to carry out the study. A comparative analysis is conducted to examine the effects of curve simplification of the roof slope, as well as the Dougong (bracket sets) and roof tile components, on the numerical simulation results of wind pressure on the building surface. Additionally, simplification schemes of geometric modeling are provided for the efficient and accurate simulation. The results indicate that moderate simplification of the roof curve has a relatively minor impact on the overall calculation of wind pressure, and the difference between the drag coefficients of the simplified model and the accurate model is no more than 3%. However, excessive simplification can lead to distorted simulation results, and a three-segment curve simplification method is recommended for roof cornices. The influence of Dougong on the wind pressure calculation results is negligible (within 5%), whereas roof tiles significantly reduce the drag coefficient, with an impact of over 30% at various wind directions. The impact of roof tiles on wind pressure distribution in traditional timber buildings lies in their alteration of the building aerodynamic shape rather than an increase in roof thickness. The findings can provide a basis for assessing the wind resistance of traditional timber buildings and helpful insights for improving the efficiency of wind pressure analyses of traditional timber structures.
{"title":"Research on wind pressure characteristics of traditional timber buildings: a case study of the main hall of Shisi Temple","authors":"Xiaoyue Gao, Qing Chun, Yidan Han","doi":"10.1186/s10086-024-02125-5","DOIUrl":"https://doi.org/10.1186/s10086-024-02125-5","url":null,"abstract":"Traditional timber buildings are sensitive to wind action. Studying the wind pressure characteristics is the premise for the preventive conservation of traditional timber buildings. To investigate the computational fluid dynamics (CFD) numerical simulation method for wind pressure on traditional timber buildings, a typical traditional timber building, the main hall of Shisi Temple, is chosen as a case to carry out the study. A comparative analysis is conducted to examine the effects of curve simplification of the roof slope, as well as the Dougong (bracket sets) and roof tile components, on the numerical simulation results of wind pressure on the building surface. Additionally, simplification schemes of geometric modeling are provided for the efficient and accurate simulation. The results indicate that moderate simplification of the roof curve has a relatively minor impact on the overall calculation of wind pressure, and the difference between the drag coefficients of the simplified model and the accurate model is no more than 3%. However, excessive simplification can lead to distorted simulation results, and a three-segment curve simplification method is recommended for roof cornices. The influence of Dougong on the wind pressure calculation results is negligible (within 5%), whereas roof tiles significantly reduce the drag coefficient, with an impact of over 30% at various wind directions. The impact of roof tiles on wind pressure distribution in traditional timber buildings lies in their alteration of the building aerodynamic shape rather than an increase in roof thickness. The findings can provide a basis for assessing the wind resistance of traditional timber buildings and helpful insights for improving the efficiency of wind pressure analyses of traditional timber structures.","PeriodicalId":17664,"journal":{"name":"Journal of Wood Science","volume":"3 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139760379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
<p><b>Correction: J Wood Sci (2021) 67:23</b> <b>https://doi.org/10.1186/s10086-021-01954-y</b></p><br/><p>In the calculation of normal and shear stress in each layer using Eqs. 7a–8b, there was an error in inputting the modulus of elasticity for Hinoki and Sugi. Erroneously, values of 12.5 GPa and 8.6 GPa were used, respectively, instead of the correct elastic moduli listed in Table 1. It should be noted that these erroneously input values were actually the partial means, consisting of the correct values found in Table 1.</p><p>Originally, the correct values were used for stiffness calculation of imaginary beam A and B.</p><p>Therefore, the impact of aforementioned input errors was confined to the calculation of sectional stress. Following the correction of these values, the recalculated results showed a slight overall increase, but it did not affect the conclusions drawn in the paper [1].</p><p>As a result of this re-calculation, corrections have been made to Figs. 11, 12, 13 and 14, as well as Tables 5 and 6.</p><figure><figcaption><b data-test="figure-caption-text">Fig. 11</b></figcaption><picture><source srcset="//media.springernature.com/lw685/springer-static/image/art%3A10.1186%2Fs10086-024-02124-6/MediaObjects/10086_2024_2124_Fig11_HTML.png?as=webp" type="image/webp"/><img alt="figure 11" aria-describedby="Fig11" height="916" loading="lazy" src="//media.springernature.com/lw685/springer-static/image/art%3A10.1186%2Fs10086-024-02124-6/MediaObjects/10086_2024_2124_Fig11_HTML.png" width="685"/></picture><p>Horizontal distribution of shear stress in the cross layer and cross-sectional shear stress distributions at representative sections</p><span>Full size image</span><svg aria-hidden="true" focusable="false" height="16" role="img" width="16"><use xlink:href="#icon-eds-i-chevron-right-small" xmlns:xlink="http://www.w3.org/1999/xlink"></use></svg></figure><figure><figcaption><b data-test="figure-caption-text">Fig. 12</b></figcaption><picture><source srcset="//media.springernature.com/lw685/springer-static/image/art%3A10.1186%2Fs10086-024-02124-6/MediaObjects/10086_2024_2124_Fig12_HTML.png?as=webp" type="image/webp"/><img alt="figure 12" aria-describedby="Fig12" height="855" loading="lazy" src="//media.springernature.com/lw685/springer-static/image/art%3A10.1186%2Fs10086-024-02124-6/MediaObjects/10086_2024_2124_Fig12_HTML.png" width="685"/></picture><p>Sample shear stress–strain curve obtained from the experiment. Shear stress is estimated by multiplying <span>({alpha }_{{text{mid}}})</span> (see Fig. 11) with the nominal shear stress</p><span>Full size image</span><svg aria-hidden="true" focusable="false" height="16" role="img" width="16"><use xlink:href="#icon-eds-i-chevron-right-small" xmlns:xlink="http://www.w3.org/1999/xlink"></use></svg></figure><figure><figcaption><b data-test="figure-caption-text">Fig. 13</b></figcaption><picture><source srcset="//media.springernature.com/lw685/springer-static/image/art%3A10.1186%2Fs10086-024-02124-6/Me
转载与许可引用本文Ukyo, S., Miyatake, A., Shindo, K. et al. Correction：杂交（桧柏和日本雪松）交叉层压材的剪切强度特性。J Wood Sci 70, 11 (2024). https://doi.org/10.1186/s10086-024-02124-6Download citationPublished: 07 February 2024DOI: https://doi.org/10.1186/s10086-024-02124-6Share this articleAnyone you share the following link with will be able to read this content:Get shareable linkSorry, a shareable link is not currently available for this article.Copy to clipboard Provided by the Springer Nature SharedIt content-sharing initiative
{"title":"Correction: Shear strength properties of hybrid (hinoki cypress and Japanese cedar) cross-laminated timber","authors":"Seiichiro Ukyo, Atsushi Miyatake, Kenta Shindo, Yasushi Hiramatsu","doi":"10.1186/s10086-024-02124-6","DOIUrl":"https://doi.org/10.1186/s10086-024-02124-6","url":null,"abstract":"<p><b>Correction: J Wood Sci (2021) 67:23</b> <b>https://doi.org/10.1186/s10086-021-01954-y</b></p><br/><p>In the calculation of normal and shear stress in each layer using Eqs. 7a–8b, there was an error in inputting the modulus of elasticity for Hinoki and Sugi. Erroneously, values of 12.5 GPa and 8.6 GPa were used, respectively, instead of the correct elastic moduli listed in Table 1. It should be noted that these erroneously input values were actually the partial means, consisting of the correct values found in Table 1.</p><p>Originally, the correct values were used for stiffness calculation of imaginary beam A and B.</p><p>Therefore, the impact of aforementioned input errors was confined to the calculation of sectional stress. Following the correction of these values, the recalculated results showed a slight overall increase, but it did not affect the conclusions drawn in the paper [1].</p><p>As a result of this re-calculation, corrections have been made to Figs. 11, 12, 13 and 14, as well as Tables 5 and 6.</p><figure><figcaption><b data-test=\"figure-caption-text\">Fig. 11</b></figcaption><picture><source srcset=\"//media.springernature.com/lw685/springer-static/image/art%3A10.1186%2Fs10086-024-02124-6/MediaObjects/10086_2024_2124_Fig11_HTML.png?as=webp\" type=\"image/webp\"/><img alt=\"figure 11\" aria-describedby=\"Fig11\" height=\"916\" loading=\"lazy\" src=\"//media.springernature.com/lw685/springer-static/image/art%3A10.1186%2Fs10086-024-02124-6/MediaObjects/10086_2024_2124_Fig11_HTML.png\" width=\"685\"/></picture><p>Horizontal distribution of shear stress in the cross layer and cross-sectional shear stress distributions at representative sections</p><span>Full size image</span><svg aria-hidden=\"true\" focusable=\"false\" height=\"16\" role=\"img\" width=\"16\"><use xlink:href=\"#icon-eds-i-chevron-right-small\" xmlns:xlink=\"http://www.w3.org/1999/xlink\"></use></svg></figure><figure><figcaption><b data-test=\"figure-caption-text\">Fig. 12</b></figcaption><picture><source srcset=\"//media.springernature.com/lw685/springer-static/image/art%3A10.1186%2Fs10086-024-02124-6/MediaObjects/10086_2024_2124_Fig12_HTML.png?as=webp\" type=\"image/webp\"/><img alt=\"figure 12\" aria-describedby=\"Fig12\" height=\"855\" loading=\"lazy\" src=\"//media.springernature.com/lw685/springer-static/image/art%3A10.1186%2Fs10086-024-02124-6/MediaObjects/10086_2024_2124_Fig12_HTML.png\" width=\"685\"/></picture><p>Sample shear stress–strain curve obtained from the experiment. Shear stress is estimated by multiplying <span>({alpha }_{{text{mid}}})</span> (see Fig. 11) with the nominal shear stress</p><span>Full size image</span><svg aria-hidden=\"true\" focusable=\"false\" height=\"16\" role=\"img\" width=\"16\"><use xlink:href=\"#icon-eds-i-chevron-right-small\" xmlns:xlink=\"http://www.w3.org/1999/xlink\"></use></svg></figure><figure><figcaption><b data-test=\"figure-caption-text\">Fig. 13</b></figcaption><picture><source srcset=\"//media.springernature.com/lw685/springer-static/image/art%3A10.1186%2Fs10086-024-02124-6/Me","PeriodicalId":17664,"journal":{"name":"Journal of Wood Science","volume":"7 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139772690","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-29DOI: 10.1186/s10086-024-02123-7
Doppo Matsubara, Masaki Teranishi, Takuro Mori
Assessing the residual performance of timber joints affected by decay is important for seismic diagnosis and reinforcement of timber structures. This study introduces a method to evaluate the embedment stiffness of metal washers in bolted timber joints using a torque wrench. Formulas for the embedment stiffness of metal washers using the torque gradient (the gradient of the tightening torque against the tightening rotation angle of the nut) and the nut factor are presented and the calculated values are compared with experimental values obtained by conducting tightening tests with a torque wrench and embedment tests of metal washers in bolted joints made from Japanese cedar, Hiba, and Japanese cypress. The results show that the experimental values of the embedment stiffness of metal washers in Japanese cedar and Hiba are generally within the range of the values calculated from the minimum and maximum values of the nut factor. However, for Japanese cypress, the values calculated from the maximum value of the nut factor exceed the experimental values. This was presumably due to locally large frictional forces generated on the bearing surface or threaded part.
{"title":"Evaluation method for embedment stiffness of metal washers in bolted timber joints using torque gradient and nut factor","authors":"Doppo Matsubara, Masaki Teranishi, Takuro Mori","doi":"10.1186/s10086-024-02123-7","DOIUrl":"https://doi.org/10.1186/s10086-024-02123-7","url":null,"abstract":"Assessing the residual performance of timber joints affected by decay is important for seismic diagnosis and reinforcement of timber structures. This study introduces a method to evaluate the embedment stiffness of metal washers in bolted timber joints using a torque wrench. Formulas for the embedment stiffness of metal washers using the torque gradient (the gradient of the tightening torque against the tightening rotation angle of the nut) and the nut factor are presented and the calculated values are compared with experimental values obtained by conducting tightening tests with a torque wrench and embedment tests of metal washers in bolted joints made from Japanese cedar, Hiba, and Japanese cypress. The results show that the experimental values of the embedment stiffness of metal washers in Japanese cedar and Hiba are generally within the range of the values calculated from the minimum and maximum values of the nut factor. However, for Japanese cypress, the values calculated from the maximum value of the nut factor exceed the experimental values. This was presumably due to locally large frictional forces generated on the bearing surface or threaded part.","PeriodicalId":17664,"journal":{"name":"Journal of Wood Science","volume":"74 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139588873","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-26DOI: 10.1186/s10086-023-02120-2
Wenpeng Zeng, Takaaki Fujimoto, Tetsuya Inagaki, Satoru Tsuchikawa, Te Ma
In past studies, finite element analysis (FEA) methods have been used to simulate the thermal and moisture coupling of wood. However, challenges remain in achieving high-quality three-dimensional (3D) simulations, mainly because of the heterogeneous and complex structure of wood and its difficult-to-detect internal structure, which makes modeling challenging, in addition to the lack of robust experimental techniques to validate simulation results. In this study, the FEA simulation model was refined by combining X-ray computed tomography (CT) and near-infrared hyperspectral imaging (NIR-HSI). CT was used to probe the 3D density of wood, and a novel FEA tetrahedral mesh was constructed based on the results. The NIR-HSI method visualizes the moisture distribution during adsorption and desorption inside the wood. This result is then used to adjust the parameters of the FEA simulation model and as a reference value to evaluate the simulation results. The visualization and simulation results fit well with the theoretical properties. The simulation results can more accurately reflect the spatial distribution and transfer trend of wood moisture at different points in time. Therefore, the CT and NIR-HSI-based 3D heat and moisture-coupled FEA model of wood proposed in this study can be used as a basis for optimizing drying parameters to provide high-quality wood.
在过去的研究中，有限元分析（FEA）方法被用于模拟木材的热耦合和湿耦合。然而，要实现高质量的三维（3D）模拟仍面临挑战，这主要是因为木材的结构异质且复杂，其内部结构难以检测，这使得建模具有挑战性，此外还缺乏可靠的实验技术来验证模拟结果。本研究结合 X 射线计算机断层扫描（CT）和近红外高光谱成像（NIR-HSI）对有限元分析模型进行了改进。CT 用于探测木材的三维密度，并根据结果构建了新型有限元分析四面体网格。近红外高光谱成像方法可以直观地显示木材内部吸附和解吸过程中的水分分布。这一结果可用于调整有限元分析模拟模型的参数，并作为评估模拟结果的参考值。可视化和模拟结果与理论特性非常吻合。模拟结果能更准确地反映木材水分在不同时间点的空间分布和转移趋势。因此，本研究提出的基于 CT 和 NIR-HSI 的木材三维热湿耦合有限元分析模型可作为优化干燥参数的基础，以提供优质木材。
{"title":"Three-dimensional modeling of moisture transport in wood using near-infrared hyperspectral imaging and X-ray computed tomography in conjunction with finite element analysis","authors":"Wenpeng Zeng, Takaaki Fujimoto, Tetsuya Inagaki, Satoru Tsuchikawa, Te Ma","doi":"10.1186/s10086-023-02120-2","DOIUrl":"https://doi.org/10.1186/s10086-023-02120-2","url":null,"abstract":"In past studies, finite element analysis (FEA) methods have been used to simulate the thermal and moisture coupling of wood. However, challenges remain in achieving high-quality three-dimensional (3D) simulations, mainly because of the heterogeneous and complex structure of wood and its difficult-to-detect internal structure, which makes modeling challenging, in addition to the lack of robust experimental techniques to validate simulation results. In this study, the FEA simulation model was refined by combining X-ray computed tomography (CT) and near-infrared hyperspectral imaging (NIR-HSI). CT was used to probe the 3D density of wood, and a novel FEA tetrahedral mesh was constructed based on the results. The NIR-HSI method visualizes the moisture distribution during adsorption and desorption inside the wood. This result is then used to adjust the parameters of the FEA simulation model and as a reference value to evaluate the simulation results. The visualization and simulation results fit well with the theoretical properties. The simulation results can more accurately reflect the spatial distribution and transfer trend of wood moisture at different points in time. Therefore, the CT and NIR-HSI-based 3D heat and moisture-coupled FEA model of wood proposed in this study can be used as a basis for optimizing drying parameters to provide high-quality wood.","PeriodicalId":17664,"journal":{"name":"Journal of Wood Science","volume":"175 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-01-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139588870","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-24DOI: 10.1186/s10086-024-02121-9
Zirui Huang, Yuling Bian, Chun Ni
Most of the currently employed methods, such as Gamma method and shear analogy method, to estimate the bending stiffness and bending capacity of cross-laminated timber (CLT) beams, are computationally extensive. In our previous study, a rolling shear analysis (RSA)-based method, which simplifies the calculation, was developed to determine the shearing capacity of CLT beams. In the present study, the authors expand upon the RSA method to determine the apparent stiffness and bending capacity of 3- and 5-layer CLT beams. By considering the shear deformation of cross layers, simplified formulas to determine the apparent bending stiffness of CLT beam was derived. Two schemes to determine the CLT bending capacity were proposed. One is based on the shear stress analysis, and the other is based on the formula specified in Canadian standard, CSA O86, by replacing the effective stiffness with the apparent stiffness. Test results from the authors and the other researchers were adopted to validate the method. The findings showed that the RSA method, using the apparent stiffness obtained from the proposed method along with the bending capacity formula in CSA O86, can provide a simpler and more reliable estimation of the apparent bending stiffness and bending capacity of CLT beams as compared to the Gamma method and shear analogy method.
{"title":"A rolling shear analysis-based method for determining the apparent stiffness and bending capacity of CLT panel under out-of-plane load","authors":"Zirui Huang, Yuling Bian, Chun Ni","doi":"10.1186/s10086-024-02121-9","DOIUrl":"https://doi.org/10.1186/s10086-024-02121-9","url":null,"abstract":"Most of the currently employed methods, such as Gamma method and shear analogy method, to estimate the bending stiffness and bending capacity of cross-laminated timber (CLT) beams, are computationally extensive. In our previous study, a rolling shear analysis (RSA)-based method, which simplifies the calculation, was developed to determine the shearing capacity of CLT beams. In the present study, the authors expand upon the RSA method to determine the apparent stiffness and bending capacity of 3- and 5-layer CLT beams. By considering the shear deformation of cross layers, simplified formulas to determine the apparent bending stiffness of CLT beam was derived. Two schemes to determine the CLT bending capacity were proposed. One is based on the shear stress analysis, and the other is based on the formula specified in Canadian standard, CSA O86, by replacing the effective stiffness with the apparent stiffness. Test results from the authors and the other researchers were adopted to validate the method. The findings showed that the RSA method, using the apparent stiffness obtained from the proposed method along with the bending capacity formula in CSA O86, can provide a simpler and more reliable estimation of the apparent bending stiffness and bending capacity of CLT beams as compared to the Gamma method and shear analogy method.","PeriodicalId":17664,"journal":{"name":"Journal of Wood Science","volume":"29 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139561606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
It has recently been suggested that processes related to water uptake from the tree-stem surface, such as water vapor exchange and rainwater permeation, have implications for forest hydrology. However, few studies have investigated stem surface water uptake itself, and the water permeation pathway has not been elucidated in detail. Based on previous findings that trees with outer bark composed mainly of rhytidome have a high frequency of exfoliation and greater water uptake ability, we hypothesized that exfoliation of the outer bark is the main pathway for water uptake from the outer bark surface to the innermost periderm in these species. We tested this hypothesis in teak, a tropical deciduous hardwood with a high frequency of outer-bark exfoliation. We conducted laboratory experiments using dried bark pieces with different outer-bark shapes to evaluate the rate, amount, and pathway of liquid-phase water permeation of outer-bark surfaces. The rate and amount of water absorption differed markedly among samples. The permeation rate was correlated with the degree of outer-bark exfoliation, and water permeation was observed to begin at exfoliated surfaces. These results support our hypothesis. In addition, the increased water content of bark pieces immediately after the start of the experiment was strongly correlated with the surface roughness of the outer bark, implying that roughness may indicate the water-retention capacity of a given tree species.
{"title":"Liquid-phase water permeation pathways on outer-bark surfaces of teak (Tectona grandis): a tropical deciduous hardwood","authors":"Hiroyuki Matsunaga, Naoko Matsuo, Takahisa Nakai, Hisashi Abe","doi":"10.1186/s10086-023-02119-9","DOIUrl":"https://doi.org/10.1186/s10086-023-02119-9","url":null,"abstract":"It has recently been suggested that processes related to water uptake from the tree-stem surface, such as water vapor exchange and rainwater permeation, have implications for forest hydrology. However, few studies have investigated stem surface water uptake itself, and the water permeation pathway has not been elucidated in detail. Based on previous findings that trees with outer bark composed mainly of rhytidome have a high frequency of exfoliation and greater water uptake ability, we hypothesized that exfoliation of the outer bark is the main pathway for water uptake from the outer bark surface to the innermost periderm in these species. We tested this hypothesis in teak, a tropical deciduous hardwood with a high frequency of outer-bark exfoliation. We conducted laboratory experiments using dried bark pieces with different outer-bark shapes to evaluate the rate, amount, and pathway of liquid-phase water permeation of outer-bark surfaces. The rate and amount of water absorption differed markedly among samples. The permeation rate was correlated with the degree of outer-bark exfoliation, and water permeation was observed to begin at exfoliated surfaces. These results support our hypothesis. In addition, the increased water content of bark pieces immediately after the start of the experiment was strongly correlated with the surface roughness of the outer bark, implying that roughness may indicate the water-retention capacity of a given tree species.","PeriodicalId":17664,"journal":{"name":"Journal of Wood Science","volume":"261 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139476645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-11DOI: 10.1186/s10086-023-02117-x
Zhi Jin, Yuejin Fu, Qian Chen, Zhen Zeng
To determine the surface relaxivity of pores plays a vital role in the application of time-domain nuclear magnetic resonance (TD-NMR) technology to porous structure characterization for wood. Currently, the surface relaxivity of pores is calibrated using a standard sample with a pore size of the same order as the wood pore system. However, the uniformly distributed pore size of standard sample is unfit to accurately indicate the complexity of porous structure of wood, which significantly affects the accuracy of test results. By integrating the TD-NMR technology with mercury intrusion porosimetry (MIP), the surface relaxivity of macropores in the lumen of wood cells is calibrated in this study using the tested sample, so as to avoid the error in measurement as caused by existing method. Data processing is performed using several mathematical methods including interpolation arithmetic and least square principle. Notably, the node segmentation method is applied to identify the T2 boundary of pores in cell lumen and to classify the porous structure of cell lumen into different pore systems. The approach proposed in this study is demonstrated to be effective in improving the accuracy of TD-NMR technology for characterizing the porous structure of wood. Also, it contributes a potential solution to accounting for the porous structure of wood based on the phenomenon of pore relaxation, which can improve the understanding of wood pore conformation.
{"title":"Determination of nuclear magnetic resonance surface relaxivity for the macropore system from wood cell lumen","authors":"Zhi Jin, Yuejin Fu, Qian Chen, Zhen Zeng","doi":"10.1186/s10086-023-02117-x","DOIUrl":"https://doi.org/10.1186/s10086-023-02117-x","url":null,"abstract":"To determine the surface relaxivity of pores plays a vital role in the application of time-domain nuclear magnetic resonance (TD-NMR) technology to porous structure characterization for wood. Currently, the surface relaxivity of pores is calibrated using a standard sample with a pore size of the same order as the wood pore system. However, the uniformly distributed pore size of standard sample is unfit to accurately indicate the complexity of porous structure of wood, which significantly affects the accuracy of test results. By integrating the TD-NMR technology with mercury intrusion porosimetry (MIP), the surface relaxivity of macropores in the lumen of wood cells is calibrated in this study using the tested sample, so as to avoid the error in measurement as caused by existing method. Data processing is performed using several mathematical methods including interpolation arithmetic and least square principle. Notably, the node segmentation method is applied to identify the T2 boundary of pores in cell lumen and to classify the porous structure of cell lumen into different pore systems. The approach proposed in this study is demonstrated to be effective in improving the accuracy of TD-NMR technology for characterizing the porous structure of wood. Also, it contributes a potential solution to accounting for the porous structure of wood based on the phenomenon of pore relaxation, which can improve the understanding of wood pore conformation.","PeriodicalId":17664,"journal":{"name":"Journal of Wood Science","volume":"12 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139420726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-05DOI: 10.1186/s10086-023-02118-w
Katsuyuki Nakano, Masahiro Koide, Yuta Yamada, Takuya Ogawa, Nobuaki Hattori
Low-rise buildings in Japan are predominantly made of wood. Furthermore, the government promotes the use of wood in mid- and high-rise buildings to tackle climate change. Therefore, the environmental impact of structural lumber should be assessed. In this study, we evaluated greenhouse gas (GHG) emissions and resource consumption associated with structural lumber production using life cycle assessment. Herein, we focused on Japanese Agricultural Standard certified structural lumber (artificially dried lumber and machine-grade structural lumber) made from Japanese roundwood. To ensure representativeness, 15 companies and 15 sawmills covering more than 50% of Japan's structural lumber production were selected and data on their production were collected. The results show that the GHG emissions and resource consumption of Japanese structural lumber are 7.99 × 10 kg-CO2e/m3 and 1.77 × 10–3 kg-Sb eq./m3, respectively. The major sources of GHG emissions are electricity and roundwood production. Roundwood and metal tools significantly affect resource consumption. The recycling of rare metals in tools is essential for reducing resource consumption. A significant amount of heat energy is utilized for drying, and this heat energy is supplied from both biomass and fossil fuels. GHG emissions and resource consumption are 5.3 and 1.6 times higher, respectively, if biomass fuel is replaced by fossil fuel. Policies supporting the introduction of biomass boilers have been highly effective. It is recommended to further promote measures such as replacing fossil fuel-based boilers with biomass boilers and effectively utilizing biomass boilers in multiple regional sawmills. In addition, switching from grid electricity to electricity generated by renewable energy sources is effective for further reducing environmental impacts. The long-term use of structural lumber is valid for combating global warming because it fixes carbon for decades. In this study, the CO2 emissions from biomasaluated in terms of carbon neutrality. Appropriate forest management is a prerequisite for carbon neutrality, and the promotion of sustainable forest management, such as reforestation after logging, is crucial.
{"title":"Environmental impacts of structural lumber production in Japan","authors":"Katsuyuki Nakano, Masahiro Koide, Yuta Yamada, Takuya Ogawa, Nobuaki Hattori","doi":"10.1186/s10086-023-02118-w","DOIUrl":"https://doi.org/10.1186/s10086-023-02118-w","url":null,"abstract":"Low-rise buildings in Japan are predominantly made of wood. Furthermore, the government promotes the use of wood in mid- and high-rise buildings to tackle climate change. Therefore, the environmental impact of structural lumber should be assessed. In this study, we evaluated greenhouse gas (GHG) emissions and resource consumption associated with structural lumber production using life cycle assessment. Herein, we focused on Japanese Agricultural Standard certified structural lumber (artificially dried lumber and machine-grade structural lumber) made from Japanese roundwood. To ensure representativeness, 15 companies and 15 sawmills covering more than 50% of Japan's structural lumber production were selected and data on their production were collected. The results show that the GHG emissions and resource consumption of Japanese structural lumber are 7.99 × 10 kg-CO2e/m3 and 1.77 × 10–3 kg-Sb eq./m3, respectively. The major sources of GHG emissions are electricity and roundwood production. Roundwood and metal tools significantly affect resource consumption. The recycling of rare metals in tools is essential for reducing resource consumption. A significant amount of heat energy is utilized for drying, and this heat energy is supplied from both biomass and fossil fuels. GHG emissions and resource consumption are 5.3 and 1.6 times higher, respectively, if biomass fuel is replaced by fossil fuel. Policies supporting the introduction of biomass boilers have been highly effective. It is recommended to further promote measures such as replacing fossil fuel-based boilers with biomass boilers and effectively utilizing biomass boilers in multiple regional sawmills. In addition, switching from grid electricity to electricity generated by renewable energy sources is effective for further reducing environmental impacts. The long-term use of structural lumber is valid for combating global warming because it fixes carbon for decades. In this study, the CO2 emissions from biomasaluated in terms of carbon neutrality. Appropriate forest management is a prerequisite for carbon neutrality, and the promotion of sustainable forest management, such as reforestation after logging, is crucial.","PeriodicalId":17664,"journal":{"name":"Journal of Wood Science","volume":"54 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139375689","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-05DOI: 10.1186/s10086-023-02110-4
Zhe Wu, Lin Chen, Haibei Xiong
The construction of structures using cross-laminated timber (CLT) has grown in popularity as a result of its environmentally friendly and high-strength characteristics. The primary function of angle bracket connections is to resist the force of CLT structures under horizontal forces, which is essential to ensure the seismic resilience and ductility of CLT structures. A regression algorithms-driven method for predicting the mechanical performance of angle bracket connections is introduced in this study. As input parameters, the geometric dimensions of the angle bracket connector, the connection method of the connector with the wall and floor slabs, and the properties of the CLT panel are utilized to predict the yield load, the maximal load, the initial stiffness, and the ductility ratio of the angle bracket connection. Prediction models were developed using the collected data from 110 angle bracket experiments, and each prediction model's performance was discussed in depth. Lastly, the permutation importance and SHapley Additive exPlanations (SHAP) value analysis were used to interpret the prediction models. The results showed that the extreme gradient boosting (XGB) algorithm could accurately predict the maximum and yielding load of the angle bracket connection, with R2 reaching 0.968 and 0.939. Furthermore, in predicting the initial stiffness of the angle bracket, the XGB algorithm performed the best with an average ratio of predicted to actual values of 0.985. The results indicated that this study proposed an accurate and efficient method for angle bracket connection to predicting its mechanical properties and confirmed the trustworthiness and feasibility of the prediction models.
{"title":"Regression algorithms-driven mechanical properties prediction of angle bracket connection on cross-laminated timber structures","authors":"Zhe Wu, Lin Chen, Haibei Xiong","doi":"10.1186/s10086-023-02110-4","DOIUrl":"https://doi.org/10.1186/s10086-023-02110-4","url":null,"abstract":"The construction of structures using cross-laminated timber (CLT) has grown in popularity as a result of its environmentally friendly and high-strength characteristics. The primary function of angle bracket connections is to resist the force of CLT structures under horizontal forces, which is essential to ensure the seismic resilience and ductility of CLT structures. A regression algorithms-driven method for predicting the mechanical performance of angle bracket connections is introduced in this study. As input parameters, the geometric dimensions of the angle bracket connector, the connection method of the connector with the wall and floor slabs, and the properties of the CLT panel are utilized to predict the yield load, the maximal load, the initial stiffness, and the ductility ratio of the angle bracket connection. Prediction models were developed using the collected data from 110 angle bracket experiments, and each prediction model's performance was discussed in depth. Lastly, the permutation importance and SHapley Additive exPlanations (SHAP) value analysis were used to interpret the prediction models. The results showed that the extreme gradient boosting (XGB) algorithm could accurately predict the maximum and yielding load of the angle bracket connection, with R2 reaching 0.968 and 0.939. Furthermore, in predicting the initial stiffness of the angle bracket, the XGB algorithm performed the best with an average ratio of predicted to actual values of 0.985. The results indicated that this study proposed an accurate and efficient method for angle bracket connection to predicting its mechanical properties and confirmed the trustworthiness and feasibility of the prediction models.","PeriodicalId":17664,"journal":{"name":"Journal of Wood Science","volume":"208 4 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139105033","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The objectives of the present study are to clarify the effect of macro- and micro-environment on the radial growth patterns and radial variation patterns of basic density in hinoki cypress (Chamaecyparis obtusa (Sieb. et Zucc.) Endl.). We evaluated the radial variation patterns of cumulative annual ring width (as radial growth pattern) and basic density by modeling methods using hinoki cypress 36 families planted at two progeny test sites. In addition, narrow-sense heritability and correlation between sites for annual ring width and basic density were investigated. As the results of modeling for radial growth patterns, radial growth patterns slightly differed between sites. In addition, the stem diameter reaching the plateau might be varied among blocks in a site. On the other hand, radial variation of basic density was affected by genetic factors rather than blocks in the site. However, the radial growth rate may somewhat affect the radial variation of basic density. The heritability and correlation coefficients between sites in basic density were higher than those of annual ring width. Therefore, although radial growth in hinoki cypress varies by the effects of micro- and macro-environmental factors and has some influence on the radial variation of basic density, basic density is more strongly affected by genetic factors than by these influences, allowing for effective improvement for wood density by tree breeding program.
本研究旨在阐明宏观和微观环境对桧柏（Chamaecyparis obtusa (Sieb. et Zucc.) Endl.）径向生长模式和基本密度径向变化规律的影响。我们利用在两个后代试验场种植的 36 个桧柏科，通过建模方法评估了累积年轮宽度（作为径向生长模式）和基本密度的径向变异模式。此外，还研究了年轮宽度和基本密度的狭义遗传率和不同地点之间的相关性。径向生长模式的建模结果表明，不同地点之间的径向生长模式略有不同。此外，达到高原的茎径在同一地点的不同区块之间也可能存在差异。另一方面，基本密度的径向变化受遗传因素的影响，而不是受地块的影响。不过，径向生长速度可能会在一定程度上影响基本密度的径向变化。与年轮宽度相比，基本密度的遗传率和地块间相关系数都更高。因此，虽然桧柏的径向生长受微观和宏观环境因素的影响而变化，并对基本密度的径向变化有一定影响，但基本密度受遗传因素的影响比受这些因素的影响更大，因此可以通过树木育种计划有效提高木材密度。
{"title":"Modeling of radial growth curves and radial variation of basic density in Chamaecyparis obtusa planted in two progeny test sites","authors":"Yusuke Takahashi, Futoshi Ishiguri, Michinari Matsushita, Ikumi Nezu, Jyunichi Ohshima, Shinso Yokota, Akira Tamura, Miyoko Tsubomura, Makoto Takahashi","doi":"10.1186/s10086-023-02116-y","DOIUrl":"https://doi.org/10.1186/s10086-023-02116-y","url":null,"abstract":"The objectives of the present study are to clarify the effect of macro- and micro-environment on the radial growth patterns and radial variation patterns of basic density in hinoki cypress (Chamaecyparis obtusa (Sieb. et Zucc.) Endl.). We evaluated the radial variation patterns of cumulative annual ring width (as radial growth pattern) and basic density by modeling methods using hinoki cypress 36 families planted at two progeny test sites. In addition, narrow-sense heritability and correlation between sites for annual ring width and basic density were investigated. As the results of modeling for radial growth patterns, radial growth patterns slightly differed between sites. In addition, the stem diameter reaching the plateau might be varied among blocks in a site. On the other hand, radial variation of basic density was affected by genetic factors rather than blocks in the site. However, the radial growth rate may somewhat affect the radial variation of basic density. The heritability and correlation coefficients between sites in basic density were higher than those of annual ring width. Therefore, although radial growth in hinoki cypress varies by the effects of micro- and macro-environmental factors and has some influence on the radial variation of basic density, basic density is more strongly affected by genetic factors than by these influences, allowing for effective improvement for wood density by tree breeding program.","PeriodicalId":17664,"journal":{"name":"Journal of Wood Science","volume":"194 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139083943","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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