Hakim Abdel Aziz Ouattara, F. Niamké, Jean Claude N'guessan Yao, Nadine Amusant, B. Garnier
Pyrolysis of lignocellulosic biomass is widely used for the production of charcoal, pyroligneous liquid, and noncondensable gases. All three are value-added products that are exploited in several fields. However, this review focuses on three main areas: wood vinegar production methods, its physicochemical properties, and the use of wood vinegar or pyroligneous acid in agriculture and the environment. Wood vinegar is a liquid derived from wood by the condensation of gases and vapors released during the carbonization process, which is the transformation of wood into charcoal. It is mainly composed of aliphatic, aromatic, and naphthenic hydrocarbons and other oxygenated compounds such as alcohols, aldehydes, ketones, furans, acids, phenols, and ethers. Wood vinegar has antioxidant and free-radical-scavenging properties and is used in agriculture as an antimicrobial, antifungal, insecticide, and plant germination and growth agent. It is also used in food preservation, in medicine, and in the ecological preservation of wood. This review also examines the state of the art in pyroligneous liquid production techniques and factors that could potentially affect its quality.
{"title":"Wood Vinegars: Production Processes, Properties, and Valorization","authors":"Hakim Abdel Aziz Ouattara, F. Niamké, Jean Claude N'guessan Yao, Nadine Amusant, B. Garnier","doi":"10.13073/fpj-d-23-00021","DOIUrl":"https://doi.org/10.13073/fpj-d-23-00021","url":null,"abstract":"\u0000 Pyrolysis of lignocellulosic biomass is widely used for the production of charcoal, pyroligneous liquid, and noncondensable gases. All three are value-added products that are exploited in several fields. However, this review focuses on three main areas: wood vinegar production methods, its physicochemical properties, and the use of wood vinegar or pyroligneous acid in agriculture and the environment. Wood vinegar is a liquid derived from wood by the condensation of gases and vapors released during the carbonization process, which is the transformation of wood into charcoal. It is mainly composed of aliphatic, aromatic, and naphthenic hydrocarbons and other oxygenated compounds such as alcohols, aldehydes, ketones, furans, acids, phenols, and ethers. Wood vinegar has antioxidant and free-radical-scavenging properties and is used in agriculture as an antimicrobial, antifungal, insecticide, and plant germination and growth agent. It is also used in food preservation, in medicine, and in the ecological preservation of wood. This review also examines the state of the art in pyroligneous liquid production techniques and factors that could potentially affect its quality.","PeriodicalId":12387,"journal":{"name":"Forest Products Journal","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46699673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Heat tensioning was proposed and proved to be effective for improving the dynamic stability of circular saw blades with ideal disk structure by a previous scholar. With the diversification of circular saw blade structure, circular saw blades with external scrapers are widely favored by the market because of their excellent resistance to sawing thermal stress. For circular saw blades with external scrapers, the effect of heat tensioning on the dynamic stability of the blades needs to be further studied. Therefore, the heat tensioning process of circular saw blades with external scrapers was built by the finite element method. The stress field and critical rotational speed of circular saw blades with a different structure after the heat tensioning process were calculated and analyzed. The relationships between circular saw blade structure, the dynamic stability of circular saw blades, and the heat tensioning process are clarified in this article. The results show that heat tensioning is not valid for all types of circular saw blades. For circular saw blades with external scrapers, the effect of heat tensioning on improving the critical rotation speed of the blades is gradually decreased with the number of external scrapers. When circular saw blades are heat tensioned, the average tangential stress of the outer edge of the blades and the critical rotation speed of the blades are higher.
{"title":"Research on the Effect of Heat Tensioning on the Dynamic Stability of Circular Saw Blades with External Scrapers","authors":"Bo Li, Mingyang Yu, Qingdong Zhang","doi":"10.13073/fpj-d-23-00014","DOIUrl":"https://doi.org/10.13073/fpj-d-23-00014","url":null,"abstract":"\u0000 Heat tensioning was proposed and proved to be effective for improving the dynamic stability of circular saw blades with ideal disk structure by a previous scholar. With the diversification of circular saw blade structure, circular saw blades with external scrapers are widely favored by the market because of their excellent resistance to sawing thermal stress. For circular saw blades with external scrapers, the effect of heat tensioning on the dynamic stability of the blades needs to be further studied. Therefore, the heat tensioning process of circular saw blades with external scrapers was built by the finite element method. The stress field and critical rotational speed of circular saw blades with a different structure after the heat tensioning process were calculated and analyzed. The relationships between circular saw blade structure, the dynamic stability of circular saw blades, and the heat tensioning process are clarified in this article. The results show that heat tensioning is not valid for all types of circular saw blades. For circular saw blades with external scrapers, the effect of heat tensioning on improving the critical rotation speed of the blades is gradually decreased with the number of external scrapers. When circular saw blades are heat tensioned, the average tangential stress of the outer edge of the blades and the critical rotation speed of the blades are higher.","PeriodicalId":12387,"journal":{"name":"Forest Products Journal","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48077138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. G. C. Uzcategui, F. França, R. D. Seale, C. A. Senalik, R. Ross
Efficient use of the available wood resources is necessary to sustainably meet the long-term demand for wood products. This paper presents research about the potential of using transverse and longitudinal vibration techniques to evaluate the bending modulus of elasticity MOE (Eb) and tensile properties (Et and UTS) of 2 by 10 No. 2 grade southern pine (Pinus spp.) lumber. A total of 285 lumber pieces were first nondestructively tested using longitudinal vibration (Director HM 200), transverse vibration (Metriguard E-computer), and proof-loading bending tests (Universal Instron Machine). Each specimen was then destructively tested in tension parallel to the grain to determine tension modulus of elasticity (Et) and ultimate tensile stress (UTS). Correlations between growth characteristics, physical, and mechanical properties were analyzed. Excellent correlative relationships between longitudinal and transverse dMOE with the elastic properties Eb, and Et were found. A strong correlation was also found between the elastic properties Eb and Et. The prediction of Eb was improved after adding density to the model. The estimation of UTS was also improved with the addition of density and a secondary nondestructive measurement. Nondestructive techniques are recommended to assess the mechanical properties of southern pine 2 by 10 lumber.
{"title":"Nondestructive Evaluation of 2 by 10 Southern Pine Lumber","authors":"M. G. C. Uzcategui, F. França, R. D. Seale, C. A. Senalik, R. Ross","doi":"10.13073/fpj-d-22-00054","DOIUrl":"https://doi.org/10.13073/fpj-d-22-00054","url":null,"abstract":"\u0000 Efficient use of the available wood resources is necessary to sustainably meet the long-term demand for wood products. This paper presents research about the potential of using transverse and longitudinal vibration techniques to evaluate the bending modulus of elasticity MOE (Eb) and tensile properties (Et and UTS) of 2 by 10 No. 2 grade southern pine (Pinus spp.) lumber. A total of 285 lumber pieces were first nondestructively tested using longitudinal vibration (Director HM 200), transverse vibration (Metriguard E-computer), and proof-loading bending tests (Universal Instron Machine). Each specimen was then destructively tested in tension parallel to the grain to determine tension modulus of elasticity (Et) and ultimate tensile stress (UTS). Correlations between growth characteristics, physical, and mechanical properties were analyzed. Excellent correlative relationships between longitudinal and transverse dMOE with the elastic properties Eb, and Et were found. A strong correlation was also found between the elastic properties Eb and Et. The prediction of Eb was improved after adding density to the model. The estimation of UTS was also improved with the addition of density and a secondary nondestructive measurement. Nondestructive techniques are recommended to assess the mechanical properties of southern pine 2 by 10 lumber.","PeriodicalId":12387,"journal":{"name":"Forest Products Journal","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45586990","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The prospect of using mass timber products, such as cross-laminated timber (CLT), for building material has increased in recent years because of the advantage of these products over their substitutes in terms of structural rigidity, cost efficiency, and climate benefits. However, the American National Standard developed for CLT currently applies to softwood only. With the expected increase in the market for CLT, the supply chain needs to address the projected rise in demand for hardwood as well. Promoting the production of hardwood mass timber like CLT requires studying the feasibility of quality hardwood lumber supply and identifying the optimal locations for investing capital in CLT manufacturing plants. By presenting a case from Tennessee, this study provides a spatially explicit framework to use a variety of factors such as transportation networks, proximity to sawmills, sawmill capacity, and roundwood supply to identify optimal CLT plant locations. Specifically, fuzzy multicriteria analysis was used to identify potential locations, which provided inputs for a location-allocation model to identify optimal locations for CLT plants. Among the several potential locations, three optimal locations suitable for CLT plants were identified with 12,504 thousand cubic feet (MCF) annual production potential of CLT panels in Tennessee. Although increasing transportation distance for lumber procurement would increase CLT production capacity, it would also result in increased lumber supply costs. Potential investors and regional planners interested in using hardwood forest products can benefit from these findings to locate suitable sites for new investment.
{"title":"Identifying Optimal Locations for Hardwood CLT Plants in Tennessee: Application of a Spatially Explicit Framework","authors":"R. Adhikari, N. Poudyal, C. Brandeis, P. Nepal","doi":"10.13073/fpj-d-23-00010","DOIUrl":"https://doi.org/10.13073/fpj-d-23-00010","url":null,"abstract":"\u0000 The prospect of using mass timber products, such as cross-laminated timber (CLT), for building material has increased in recent years because of the advantage of these products over their substitutes in terms of structural rigidity, cost efficiency, and climate benefits. However, the American National Standard developed for CLT currently applies to softwood only. With the expected increase in the market for CLT, the supply chain needs to address the projected rise in demand for hardwood as well. Promoting the production of hardwood mass timber like CLT requires studying the feasibility of quality hardwood lumber supply and identifying the optimal locations for investing capital in CLT manufacturing plants. By presenting a case from Tennessee, this study provides a spatially explicit framework to use a variety of factors such as transportation networks, proximity to sawmills, sawmill capacity, and roundwood supply to identify optimal CLT plant locations. Specifically, fuzzy multicriteria analysis was used to identify potential locations, which provided inputs for a location-allocation model to identify optimal locations for CLT plants. Among the several potential locations, three optimal locations suitable for CLT plants were identified with 12,504 thousand cubic feet (MCF) annual production potential of CLT panels in Tennessee. Although increasing transportation distance for lumber procurement would increase CLT production capacity, it would also result in increased lumber supply costs. Potential investors and regional planners interested in using hardwood forest products can benefit from these findings to locate suitable sites for new investment.","PeriodicalId":12387,"journal":{"name":"Forest Products Journal","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47861531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Slash pine plantation economic returns from both timber and pine straw producing perspectives were compared. Bare land values (BLVs) were calculated for site index 65 (base age 25) across three discount rates (4%, 5%, and 6%), three planting densities [545 (8 by 10 ft), 623 (7 by 10 ft), and 726 (6 by 10 ft) trees per acre], and two sets of timber prices (30-year and 10-year averages). Timber yields were obtained from the Cutover Slash Growth and Yield Simulator. Straw yields were estimated stochastically using a two-parameter Weibull distribution based on findings from a summary of pine straw yields and economic benefits in loblolly, longleaf, and slash pine stands. Straw production at an estimated average of 198 bales per acre (13 by 13 by 26 inches) improved net economic returns across all discount rates and planting densities. Increasing discount rates expectedly lowered BLVs. The BLVs varied much less across spacings, with planting at 7 by 10 ft being the preferred option. From 159 to 164 bales per acre were needed for pine straw operations to break even when planting 623 trees per acre depending on the discount rate. The distance from the average BLV to the 90th percentile was greater than the distance from the average BLV to the 10th percentile across strategies. This implied a greater potential existed for pine straw harvesting to improve BLV, but risk associated with a pine straw enterprise could reduce net income levels below simply choosing to forgo this activity.
{"title":"Assessing Income and Risk of Incorporating Pine Straw Production into Slash Pine Plantations","authors":"T. McConnell","doi":"10.13073/fpj-d-23-00003","DOIUrl":"https://doi.org/10.13073/fpj-d-23-00003","url":null,"abstract":"\u0000 Slash pine plantation economic returns from both timber and pine straw producing perspectives were compared. Bare land values (BLVs) were calculated for site index 65 (base age 25) across three discount rates (4%, 5%, and 6%), three planting densities [545 (8 by 10 ft), 623 (7 by 10 ft), and 726 (6 by 10 ft) trees per acre], and two sets of timber prices (30-year and 10-year averages). Timber yields were obtained from the Cutover Slash Growth and Yield Simulator. Straw yields were estimated stochastically using a two-parameter Weibull distribution based on findings from a summary of pine straw yields and economic benefits in loblolly, longleaf, and slash pine stands. Straw production at an estimated average of 198 bales per acre (13 by 13 by 26 inches) improved net economic returns across all discount rates and planting densities. Increasing discount rates expectedly lowered BLVs. The BLVs varied much less across spacings, with planting at 7 by 10 ft being the preferred option. From 159 to 164 bales per acre were needed for pine straw operations to break even when planting 623 trees per acre depending on the discount rate. The distance from the average BLV to the 90th percentile was greater than the distance from the average BLV to the 10th percentile across strategies. This implied a greater potential existed for pine straw harvesting to improve BLV, but risk associated with a pine straw enterprise could reduce net income levels below simply choosing to forgo this activity.","PeriodicalId":12387,"journal":{"name":"Forest Products Journal","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41554197","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The balance among forest industry development, forest operators' well-being, and environmental conservation has been noted as an emerging concern in forest sustainability strategy. In this study, we innovatively adopted a multidimensional assessment method that integrates economic, environmental, and social dimensions to compare the comprehensive sustainability of roundwood, bamboo, tea products, and fruit industries, which are representative subtypes of the timber industry and the nontimber forest products (NTFP) industry. Additionally, our study examined whether a relationship exists between the forest industry's comprehensive sustainability and operators' proactiveness. We collected data on selected types of forest operators involved in productive loans from 115 villages in southern China between 2008 and 2020. Empirical results indicate that an increase in the comprehensive sustainability rank of the subtype forest industry led to growth in forest operators' financing amount. Specifically, the NTFP industry motivated operators' proactiveness more than did the timber industry, the effect of which was considerably greater in company group than in household group. Our findings reveal the necessity of policy interventions in developing countries to encourage the transition to optimizing forest industrial structure and sustainable forestry operations, which could initiate the socio-economic goal of sustained forest resource use and growth in forest sector output through the natural promotion effect posed by the sustainability advantages.
{"title":"A Comparative Analysis Between Timber Industry and Nontimber Forest Products Industry in Relation to Sustainability and Operators' Proactiveness","authors":"Yixuan Luo, Xiao Feng","doi":"10.13073/fpj-d-22-00065","DOIUrl":"https://doi.org/10.13073/fpj-d-22-00065","url":null,"abstract":"\u0000 The balance among forest industry development, forest operators' well-being, and environmental conservation has been noted as an emerging concern in forest sustainability strategy. In this study, we innovatively adopted a multidimensional assessment method that integrates economic, environmental, and social dimensions to compare the comprehensive sustainability of roundwood, bamboo, tea products, and fruit industries, which are representative subtypes of the timber industry and the nontimber forest products (NTFP) industry. Additionally, our study examined whether a relationship exists between the forest industry's comprehensive sustainability and operators' proactiveness. We collected data on selected types of forest operators involved in productive loans from 115 villages in southern China between 2008 and 2020. Empirical results indicate that an increase in the comprehensive sustainability rank of the subtype forest industry led to growth in forest operators' financing amount. Specifically, the NTFP industry motivated operators' proactiveness more than did the timber industry, the effect of which was considerably greater in company group than in household group. Our findings reveal the necessity of policy interventions in developing countries to encourage the transition to optimizing forest industrial structure and sustainable forestry operations, which could initiate the socio-economic goal of sustained forest resource use and growth in forest sector output through the natural promotion effect posed by the sustainability advantages.","PeriodicalId":12387,"journal":{"name":"Forest Products Journal","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44438570","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fourteen 1,220 by 2,440 by 11.1-mm commercial Oriented Strandboard (OSB) panels were X-ray scanned to obtain horizontal density matrices. Localized densities around the concentrated static load (CSL) testing points of the panels were calculated prior to the CSL test. A linear regression analysis was conducted to assess the impact of the localized density on CSL performance. The results indicated that both deflection and ultimate load were highly correlated with the local density. Deflection and ultimate load were somewhat correlated (R2 = 0.52). The CSL deflection decreased and ultimate load increased significantly with increasing local density. The impact of local density on ultimate load was greater than on deflection. Horizontal density variation is inherent in OSB manufacturing processes, especially in the mat forming process. A number of factors, including evenness of strands in the metering bin, condition of picker rolls and dissolving rolls, and strand and fines surging, can affect horizontal density distribution. OSB panels with a high degree of variation in horizontal panel density may cause low density spots that increase the chance of failure in CSL test. It is therefore crucial to minimize the occurrence of very low density areas in order to reduce the odds of ultimate load failure. Reducing density variability allows OSB companies to increase the CSL properties of their products, which would otherwise need to be done by making the panel denser. Improving horizontal density uniformity allows for lowering of the average panel density, which reduces the manufacturing cost and helps improve the company's bottom line.
{"title":"Influence of Local Density on Concentrated Static Load Performance of Oriented Strandboard","authors":"Siguo Chen, R. Knudson","doi":"10.13073/fpj-d-23-00001","DOIUrl":"https://doi.org/10.13073/fpj-d-23-00001","url":null,"abstract":"\u0000 Fourteen 1,220 by 2,440 by 11.1-mm commercial Oriented Strandboard (OSB) panels were X-ray scanned to obtain horizontal density matrices. Localized densities around the concentrated static load (CSL) testing points of the panels were calculated prior to the CSL test. A linear regression analysis was conducted to assess the impact of the localized density on CSL performance. The results indicated that both deflection and ultimate load were highly correlated with the local density. Deflection and ultimate load were somewhat correlated (R2 = 0.52). The CSL deflection decreased and ultimate load increased significantly with increasing local density. The impact of local density on ultimate load was greater than on deflection. Horizontal density variation is inherent in OSB manufacturing processes, especially in the mat forming process. A number of factors, including evenness of strands in the metering bin, condition of picker rolls and dissolving rolls, and strand and fines surging, can affect horizontal density distribution. OSB panels with a high degree of variation in horizontal panel density may cause low density spots that increase the chance of failure in CSL test. It is therefore crucial to minimize the occurrence of very low density areas in order to reduce the odds of ultimate load failure. Reducing density variability allows OSB companies to increase the CSL properties of their products, which would otherwise need to be done by making the panel denser. Improving horizontal density uniformity allows for lowering of the average panel density, which reduces the manufacturing cost and helps improve the company's bottom line.","PeriodicalId":12387,"journal":{"name":"Forest Products Journal","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46572008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Considering the high demand for housing and the ongoing environmental issues our society faces, it's crucial to opt for more ecofriendly materials for building purposes. In that scenario, engineered wood products play an important role as they are not only based on a sustainable material but also can reduce the carbon footprint from construction. Cross-laminated timber (CLT) is one of the products that could expand wood products use while keeping up with low and mid-rise building needs. Although CLT use has been expanding in the United States for the last few years, there is still a high necessity for understanding this composite behavior. One of those needs is assessing the effect of notching on the panels and measuring strength reduction as well as possible reinforcement methods. The goal of this project was to evaluate the performance of CLT panels focusing on strength and stiffness properties. Mechanical bending testing of three-ply southern pine CLT samples was performed to evaluate the influence of notches and stitching reinforcement on panels. The strength reduction caused by notching was successfully measured. Control samples supported significantly higher loads than notched samples. However, it was found that the deeper the notch, the more effective the stitching can be regarding strength. Control samples presented cross-grain tension and splintering tension failure modes, whereas notched samples presented simple tension failure mode. The findings of this work are of great value toward updating manufacturing, design, and use criteria for notched CLT panels and can be potentially used in future building codes.
{"title":"Effect of Notching on Three-Ply Southern Pine Cross-Laminated Timber Panel Stiffness and Strength","authors":"L. M. Spinelli Correa, R. Shmulsky, R. Ross","doi":"10.13073/fpj-d-22-00071","DOIUrl":"https://doi.org/10.13073/fpj-d-22-00071","url":null,"abstract":"\u0000 Considering the high demand for housing and the ongoing environmental issues our society faces, it's crucial to opt for more ecofriendly materials for building purposes. In that scenario, engineered wood products play an important role as they are not only based on a sustainable material but also can reduce the carbon footprint from construction. Cross-laminated timber (CLT) is one of the products that could expand wood products use while keeping up with low and mid-rise building needs. Although CLT use has been expanding in the United States for the last few years, there is still a high necessity for understanding this composite behavior. One of those needs is assessing the effect of notching on the panels and measuring strength reduction as well as possible reinforcement methods. The goal of this project was to evaluate the performance of CLT panels focusing on strength and stiffness properties. Mechanical bending testing of three-ply southern pine CLT samples was performed to evaluate the influence of notches and stitching reinforcement on panels. The strength reduction caused by notching was successfully measured. Control samples supported significantly higher loads than notched samples. However, it was found that the deeper the notch, the more effective the stitching can be regarding strength. Control samples presented cross-grain tension and splintering tension failure modes, whereas notched samples presented simple tension failure mode. The findings of this work are of great value toward updating manufacturing, design, and use criteria for notched CLT panels and can be potentially used in future building codes.","PeriodicalId":12387,"journal":{"name":"Forest Products Journal","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43133902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yan Yang, Bin Li, Yuqing Liu, Wenqiang Zhang, Chuanbo Wang
The identification of the tree species and the extent of material deterioration in the wooden components of the walkway of the first courtyard of the ancient Yangjia Courtyard were analyzed in this study using bright-field microscopy, polarized light, fluorescence, and Fourier-transform infrared (FTIR) spectroscopy methods. The results are as follows: (1) samples No. 1 and No. 2, and No. 4, No. 3, and No. 5 taken from the roots of the wooden pillars were identified as lace-bark pine wood (Pinus bungeana), poplar woods (Populus spp.), large-fruited elm wood (Ulmus macrocarpa), and spruce wood (Picea sp.), respectively on the basis of observation of anatomical structural characteristics and analysis of selection principle of “local selection” in ancient buildings. (2) The observation of polarization and fluorescence and the analysis of FTIR spectra showed that the brightness of crystalline cellulose birefringence reduced severely, and analysis of FTIR spectra showed that the absorption peaks representing cellulose and hemicellulose in the lace-bark pine and spruce wooden components disappeared or decreased. However, the polarization and fluorescence and the FTIR spectra of the poplar and elm wooden components showed that the brightness of the crystalline cellulose birefringence and the absorption peaks remained constant, as the controls did. (3) According to the results of the effects of the polarization and fluorescence effects and the FTIR spectra, we concluded that the lace-bark pine and spruce wooden components were severely attacked by brown rot fungi; in contrast, the wooden components of poplar and elm were not attacked by wood decay fungus, but were attacked by insects. These results provide scientific guidance for subsequent preventive conservation such as preservative treatment and insect prevention.
{"title":"Identification of Tree Species and Extent of Material Deterioration of Wood Components in the Yangjia Courtyard Ancient Building","authors":"Yan Yang, Bin Li, Yuqing Liu, Wenqiang Zhang, Chuanbo Wang","doi":"10.13073/fpj-d-22-00068","DOIUrl":"https://doi.org/10.13073/fpj-d-22-00068","url":null,"abstract":"\u0000 The identification of the tree species and the extent of material deterioration in the wooden components of the walkway of the first courtyard of the ancient Yangjia Courtyard were analyzed in this study using bright-field microscopy, polarized light, fluorescence, and Fourier-transform infrared (FTIR) spectroscopy methods. The results are as follows: (1) samples No. 1 and No. 2, and No. 4, No. 3, and No. 5 taken from the roots of the wooden pillars were identified as lace-bark pine wood (Pinus bungeana), poplar woods (Populus spp.), large-fruited elm wood (Ulmus macrocarpa), and spruce wood (Picea sp.), respectively on the basis of observation of anatomical structural characteristics and analysis of selection principle of “local selection” in ancient buildings. (2) The observation of polarization and fluorescence and the analysis of FTIR spectra showed that the brightness of crystalline cellulose birefringence reduced severely, and analysis of FTIR spectra showed that the absorption peaks representing cellulose and hemicellulose in the lace-bark pine and spruce wooden components disappeared or decreased. However, the polarization and fluorescence and the FTIR spectra of the poplar and elm wooden components showed that the brightness of the crystalline cellulose birefringence and the absorption peaks remained constant, as the controls did. (3) According to the results of the effects of the polarization and fluorescence effects and the FTIR spectra, we concluded that the lace-bark pine and spruce wooden components were severely attacked by brown rot fungi; in contrast, the wooden components of poplar and elm were not attacked by wood decay fungus, but were attacked by insects. These results provide scientific guidance for subsequent preventive conservation such as preservative treatment and insect prevention.","PeriodicalId":12387,"journal":{"name":"Forest Products Journal","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46390905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Musah, A. Alawode, Javier Hernandez Diaz, O. Asafu-Adjaye, T. Gallagher, M. Peresin, Yucheng Peng, D. Mitchell, M. Smidt, B. Via
Near-infrared reflectance (NIR) spectroscopy was used to determine correlations between acoustic velocity and stiffness properties of downed pine trees in the southern coastal plains of the United States. Three acoustic measurement methods (longitudinal, transverse, and offset) were used. From the measurement of the acoustics, the time of flight (TOF) was determined from the downed trees. Increment core samples were obtained from each thirty downed pine trees in the study. NIR spectra were obtained using a fiber probe on the radial surface of each core to rapidly correlate the speed of sound, estimate the strength properties of the downed trees, and the TOF acoustic assessments. The NIR prediction was very good for the transverse and offset methods. The predictability diagnostic was above an R2 of 0.70 for both offset measurements for the transverse methods for the acoustic velocity and dynamic modulus of elasticity (MOE). The longitudinal measurement exhibited the weakest model (R2 < 0.65) for both the acoustic velocity and the MOE with the highest standard error of prediction between 3.0 (ELVLSWV) and 0.31 (VLSWV) for the three measurement types. All the standard errors of calibration were below 1% except in ELVOSWV, which was ∼2%. The dry density measured from the increment cores had a moderate correlation (R2 ∼ 60%), compared with the lower correlation (R2 ∼ 50%) by the green density in the multiple linear regression output. The results of the acoustic model indicated that NIR spectroscopy has the potential to predict the acoustic velocity and corresponding stiffness of downed trees.
{"title":"Prediction of Acoustic Velocity Properties of Downed Pine Trees Using Near-Infrared Spectroscopy","authors":"M. Musah, A. Alawode, Javier Hernandez Diaz, O. Asafu-Adjaye, T. Gallagher, M. Peresin, Yucheng Peng, D. Mitchell, M. Smidt, B. Via","doi":"10.13073/fpj-d-22-00067","DOIUrl":"https://doi.org/10.13073/fpj-d-22-00067","url":null,"abstract":"\u0000 Near-infrared reflectance (NIR) spectroscopy was used to determine correlations between acoustic velocity and stiffness properties of downed pine trees in the southern coastal plains of the United States. Three acoustic measurement methods (longitudinal, transverse, and offset) were used. From the measurement of the acoustics, the time of flight (TOF) was determined from the downed trees. Increment core samples were obtained from each thirty downed pine trees in the study. NIR spectra were obtained using a fiber probe on the radial surface of each core to rapidly correlate the speed of sound, estimate the strength properties of the downed trees, and the TOF acoustic assessments. The NIR prediction was very good for the transverse and offset methods. The predictability diagnostic was above an R2 of 0.70 for both offset measurements for the transverse methods for the acoustic velocity and dynamic modulus of elasticity (MOE). The longitudinal measurement exhibited the weakest model (R2 < 0.65) for both the acoustic velocity and the MOE with the highest standard error of prediction between 3.0 (ELVLSWV) and 0.31 (VLSWV) for the three measurement types. All the standard errors of calibration were below 1% except in ELVOSWV, which was ∼2%. The dry density measured from the increment cores had a moderate correlation (R2 ∼ 60%), compared with the lower correlation (R2 ∼ 50%) by the green density in the multiple linear regression output. The results of the acoustic model indicated that NIR spectroscopy has the potential to predict the acoustic velocity and corresponding stiffness of downed trees.","PeriodicalId":12387,"journal":{"name":"Forest Products Journal","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48361616","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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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