Arijit Sinha, K. Udele, Jed Cappellazzi, J. Morrell
Biological durability issues in cross-laminated timber (CLT) have been majorly ignored in North America because of the European origin of the material and careful construction practices in Europe. However, the risks of fungal and insect attacks are increased by the North American climatic conditions and lack of job-site measures to keep the material dry. The methods to evaluate durability in solid timber are inadequate for use in mass timber (MT) for a number of reasons, such as moisture variation and size being critical issues. This study therefore proposes a method, which is suitable to evaluate the strength of MT assemblies that are exposed to fungal degradation. The objective of the study was to explore a controlled method for assessing the effects of wetting and subsequent fungal attack on the behavior of CLT connections. Two different methods were used to create fungal attack on CLT assemblies. Although they were both successful, one was cumbersome, left room for many errors, and was not as efficient as the other. In addition, a standardized method to evaluate and characterize key performance metric for the connections is presented.
{"title":"A Method to Characterize Biological Degradation of Mass Timber Connections","authors":"Arijit Sinha, K. Udele, Jed Cappellazzi, J. Morrell","doi":"10.22382/wfs-2020-040","DOIUrl":"https://doi.org/10.22382/wfs-2020-040","url":null,"abstract":"Biological durability issues in cross-laminated timber (CLT) have been majorly ignored in North America because of the European origin of the material and careful construction practices in Europe. However, the risks of fungal and insect attacks are increased by the North American climatic conditions and lack of job-site measures to keep the material dry. The methods to evaluate durability in solid timber are inadequate for use in mass timber (MT) for a number of reasons, such as moisture variation and size being critical issues. This study therefore proposes a method, which is suitable to evaluate the strength of MT assemblies that are exposed to fungal degradation. The objective of the study was to explore a controlled method for assessing the effects of wetting and subsequent fungal attack on the behavior of CLT connections. Two different methods were used to create fungal attack on CLT assemblies. Although they were both successful, one was cumbersome, left room for many errors, and was not as efficient as the other. In addition, a standardized method to evaluate and characterize key performance metric for the connections is presented.","PeriodicalId":23620,"journal":{"name":"Wood and Fiber Science","volume":"52 1","pages":"419-430"},"PeriodicalIF":1.4,"publicationDate":"2020-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45384067","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. A. Senalik, F. França, R. D. Seale, R. Ross, R. Shmulsky
This research article summarizes results from Part 1 of a study designed to examine using advanced signal processing techniques with acoustic-based lumber assessment technologies to evaluate the MOE, ultimate tension stress (UTS), and MOR of structural lumber. In Part 1 of this research article, a mathematical model of acoustic wave behavior in an idealized specimen is derived using fundamental mechanics. Published information on the physical and mechanical properties of clear, defect-free wood is input into the model to examine acoustic wave behavior. Wave behavior is then examined experimentally in a series of wood specimens. Observed wave behavior in the clear wood specimens, in both time and frequency domains, closely resembles idealized wave behavior. In Part 2 of this research article, predictions from the model are used to improve estimation of the UTS of wood specimens.
{"title":"Estimating lumber properties with acoustic-based technologies—Part 1: Modeling acoustic (stress) wave behavior in clear wood and lumber","authors":"C. A. Senalik, F. França, R. D. Seale, R. Ross, R. Shmulsky","doi":"10.22382/wfs-2020-036","DOIUrl":"https://doi.org/10.22382/wfs-2020-036","url":null,"abstract":"This research article summarizes results from Part 1 of a study designed to examine using advanced signal processing techniques with acoustic-based lumber assessment technologies to evaluate the MOE, ultimate tension stress (UTS), and MOR of structural lumber. In Part 1 of this research article, a mathematical model of acoustic wave behavior in an idealized specimen is derived using fundamental mechanics. Published information on the physical and mechanical properties of clear, defect-free wood is input into the model to examine acoustic wave behavior. Wave behavior is then examined experimentally in a series of wood specimens. Observed wave behavior in the clear wood specimens, in both time and frequency domains, closely resembles idealized wave behavior. In Part 2 of this research article, predictions from the model are used to improve estimation of the UTS of wood specimens.","PeriodicalId":23620,"journal":{"name":"Wood and Fiber Science","volume":"52 1","pages":"380-389"},"PeriodicalIF":1.4,"publicationDate":"2020-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42036217","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Editorial: Letter from SWST President Kutnar","authors":"A. Kutnar","doi":"10.22382/wfs-2020-032","DOIUrl":"https://doi.org/10.22382/wfs-2020-032","url":null,"abstract":"","PeriodicalId":23620,"journal":{"name":"Wood and Fiber Science","volume":"52 1","pages":"345-345"},"PeriodicalIF":1.4,"publicationDate":"2020-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46502540","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. C. Lengowski, E. A. B. Júnior, B. Vatras, P. Neto, J. M. R. Barros, S. Nisgoski
The study of the technological characteristics of wood is of great importance as it provides information that may help to direct its best use. It is also useful in forest breeding programs and in the choice of which species to plant. Traditionally, the most planted tree in Brazil is the hybrid Eucalyptus grandis x Eucalyptus urophylla . The planting of Eucalyptus in Brazilian cold regions has intensified in recent years, and this and other species of the genus have also been used for this. Wood basic density, fiber dimensions, chemical composition, and higher heating value (HHV) of Eucalyptus benthamii , Eucalyptus dunnii , and Eucalyptus saligna , all species with a tolerance to frost, were analyzed. Basic densities, all greater than 460 kg/m 3 , were not significantly different among species. E. dunnii had the longest fiber ().98 mm), the highest holocellulose content, and the lowest lignin content, showing its potential for pulping. E. Benthamii and E. Saligna together have higher lignin content with greater HHV, and so are more indicated for energy. Total extractive and ash content were high, but there were no significant differences among the species.
{"title":"Technical Note: Properties of Wood from Frost-Tolerant Eucalyptus Planted in Brazil","authors":"E. C. Lengowski, E. A. B. Júnior, B. Vatras, P. Neto, J. M. R. Barros, S. Nisgoski","doi":"10.22382/wfs-2020-041","DOIUrl":"https://doi.org/10.22382/wfs-2020-041","url":null,"abstract":"The study of the technological characteristics of wood is of great importance as it provides information that may help to direct its best use. It is also useful in forest breeding programs and in the choice of which species to plant. Traditionally, the most planted tree in Brazil is the hybrid Eucalyptus grandis x Eucalyptus urophylla . The planting of Eucalyptus in Brazilian cold regions has intensified in recent years, and this and other species of the genus have also been used for this. Wood basic density, fiber dimensions, chemical composition, and higher heating value (HHV) of Eucalyptus benthamii , Eucalyptus dunnii , and Eucalyptus saligna , all species with a tolerance to frost, were analyzed. Basic densities, all greater than 460 kg/m 3 , were not significantly different among species. E. dunnii had the longest fiber ().98 mm), the highest holocellulose content, and the lowest lignin content, showing its potential for pulping. E. Benthamii and E. Saligna together have higher lignin content with greater HHV, and so are more indicated for energy. Total extractive and ash content were high, but there were no significant differences among the species.","PeriodicalId":23620,"journal":{"name":"Wood and Fiber Science","volume":"52 1","pages":"431-435"},"PeriodicalIF":1.4,"publicationDate":"2020-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49075701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The objective of this study was to investigate tensile properties of two grape cane fibers, namely, outer bark (OB) and inner bark (IB). The cane is a necessary annual by-product from vineyards and is produced at approximately 36 million tons yearly around the world, which currently has no substantial commercial utilization. Grape cane fibers were subjected to an alkali treatment, at different concentrations, to separate the fibers from the cane. Moreover, two displacement methods such as system compliance ( C s ) and digital image correlation (DIC) were performed to determine Young’s modulus of the samples, and the results were compared. The OB fibers had better overall properties than IB fibers. The effect of the treatment concentrations (1, 3, 5, and 7 wt% of sodium hydroxide) and gage lengths (10, 25, and 40 mm) on the tensile properties was not consistent for both fiber types. The DIC method consistently yielded greater tensile modulus of the samples than the C s method for OB fibers.
{"title":"Effect of Alkali Treatment on the Tensile Properties of Grape Cane Fibers by Integrating Digital Image Correlation Method","authors":"B. F. A. Bakar, F. Kamke","doi":"10.22382/wfs-2020-035","DOIUrl":"https://doi.org/10.22382/wfs-2020-035","url":null,"abstract":"The objective of this study was to investigate tensile properties of two grape cane fibers, namely, outer bark (OB) and inner bark (IB). The cane is a necessary annual by-product from vineyards and is produced at approximately 36 million tons yearly around the world, which currently has no substantial commercial utilization. Grape cane fibers were subjected to an alkali treatment, at different concentrations, to separate the fibers from the cane. Moreover, two displacement methods such as system compliance ( C s ) and digital image correlation (DIC) were performed to determine Young’s modulus of the samples, and the results were compared. The OB fibers had better overall properties than IB fibers. The effect of the treatment concentrations (1, 3, 5, and 7 wt% of sodium hydroxide) and gage lengths (10, 25, and 40 mm) on the tensile properties was not consistent for both fiber types. The DIC method consistently yielded greater tensile modulus of the samples than the C s method for OB fibers.","PeriodicalId":23620,"journal":{"name":"Wood and Fiber Science","volume":"52 1","pages":"365-379"},"PeriodicalIF":1.4,"publicationDate":"2020-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41396034","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The aim of this study was to examine the effect of tenon and mortise joints on Young's modulus of wooden members and propose a correcting method of Young's modulus. Young's moduli of the specimens with two additional concentrated masses (CMs) and those of the specimens with tenon and mortise joints were obtained using the longitudinal vibration test. The frequency equation for the longitudinal vibration of a specimen with two additional CMs was experimentally proved. The maximum deviation of 17% in Young's modulus was observed when the specimens with tenon and mortise joints were treated as rectangular bars. The mass ratio (mass of a tenon and a mortise/mass of the main body) and the volume ratio (volume of a tenon and a mortise/volume of the main body) could be used for the aforementioned frequency equation. Using this method, it is possible for one to accurately estimate Young's modulus of a wooden member with a tenon and a mortise on a construction site.
{"title":"Determining Young’s Modulus of Wooden Members with Tenon and Mortise Joint Using Longitudinal Vibration","authors":"Y. Kubojima, Satomi Sonoda, Hideo Kato","doi":"10.22382/wfs-2020-038","DOIUrl":"https://doi.org/10.22382/wfs-2020-038","url":null,"abstract":"The aim of this study was to examine the effect of tenon and mortise joints on Young's modulus of wooden members and propose a correcting method of Young's modulus. Young's moduli of the specimens with two additional concentrated masses (CMs) and those of the specimens with tenon and mortise joints were obtained using the longitudinal vibration test. The frequency equation for the longitudinal vibration of a specimen with two additional CMs was experimentally proved. The maximum deviation of 17% in Young's modulus was observed when the specimens with tenon and mortise joints were treated as rectangular bars. The mass ratio (mass of a tenon and a mortise/mass of the main body) and the volume ratio (volume of a tenon and a mortise/volume of the main body) could be used for the aforementioned frequency equation. Using this method, it is possible for one to accurately estimate Young's modulus of a wooden member with a tenon and a mortise on a construction site.","PeriodicalId":23620,"journal":{"name":"Wood and Fiber Science","volume":"52 1","pages":"400-409"},"PeriodicalIF":1.4,"publicationDate":"2020-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43994897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Bamboo hardness test standards are not available. The study aimed to develop a new method of testing bamboo indentation hardness. With the V-shaped prismatic head, bamboo rings with different lengths were tested. The V-shaped indentation coefficient (IC) was defined. The results showed that the IC had a good correlation with compression strength. The V-shaped IC increased with the increase in the longitudinal height of the bamboo pole, and the variance analysis showed significant differences in different axial directions of the same bamboo ring. In addition, the correlation between density and IC is good. The V-shaped IC can be applied in bamboo gra
{"title":"Indentation Coefficient and Indentation Behavior of Bamboo","authors":"Xiaomeng Yang, Huanrong Liu, Yuan Chai, Zhengjun Sun, B. Fei, Zehui Jiang","doi":"10.22382/wfs-2020-033","DOIUrl":"https://doi.org/10.22382/wfs-2020-033","url":null,"abstract":"Bamboo hardness test standards are not available. The study aimed to develop a new method of testing bamboo indentation hardness. With the V-shaped prismatic head, bamboo rings with different lengths were tested. The V-shaped indentation coefficient (IC) was defined. The results showed that the IC had a good correlation with compression strength. The V-shaped IC increased with the increase in the longitudinal height of the bamboo pole, and the variance analysis showed significant differences in different axial directions of the same bamboo ring. In addition, the correlation between density and IC is good. The V-shaped IC can be applied in bamboo gra","PeriodicalId":23620,"journal":{"name":"Wood and Fiber Science","volume":"52 1","pages":"346-355"},"PeriodicalIF":1.4,"publicationDate":"2020-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48245780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Many millions of bags of mulch are sold at retail in the United States each year. Most mulch products claim to be of a certain species, with cypress being perhaps the most widely marketed. Unfortunately, it is practically impossible for the average consumer to know with certainty whether a product is indeed the species listed on the packaging. Claims of misleading behavior by some producers raise the question of whether species mix should be more closely monitored. Regulators charged with ensuring fair competition and consumer welfare, however, do not have an accurate means to determine species content. It would be difficult, if not impossible, to determine the species mix for 100% of the wood particles in a package of mulch because of the inability to identify species of the smallest particles, and the impracticality of 100% sampling in the intended use. We propose and develop a new method to allow analysts to estimate the percentage of a given species in samples of mulch, with a focus on cypress. This case study illustrates our methods and highlights the challenges in accurately determining species mix in the type of wood product. We purchased and tested 10 bags of cypress mulch obtained from six different states. Results indicate that one producer was filling some bags with only 50% cypress and others with no cypress. Consumers may therefore suffer as they receive a lower valued species, whereas honest competitors are also harmed. The wood science community could help regulators and consumers by developing a method by which small particles of wood could be positively identified as to species. Improved methods for species identification are relevant for a wide variety of purposes ranging from identifying consumer products to upholding the U.S. Lacey Act.
{"title":"New Protocol for Species Mix Testing in Retail Mulch Sample","authors":"J. Michael, Chuck D. Ray","doi":"10.22382/wfs-2020-034","DOIUrl":"https://doi.org/10.22382/wfs-2020-034","url":null,"abstract":"Many millions of bags of mulch are sold at retail in the United States each year. Most mulch products claim to be of a certain species, with cypress being perhaps the most widely marketed. Unfortunately, it is practically impossible for the average consumer to know with certainty whether a product is indeed the species listed on the packaging. Claims of misleading behavior by some producers raise the question of whether species mix should be more closely monitored. Regulators charged with ensuring fair competition and consumer welfare, however, do not have an accurate means to determine species content. It would be difficult, if not impossible, to determine the species mix for 100% of the wood particles in a package of mulch because of the inability to identify species of the smallest particles, and the impracticality of 100% sampling in the intended use. We propose and develop a new method to allow analysts to estimate the percentage of a given species in samples of mulch, with a focus on cypress. This case study illustrates our methods and highlights the challenges in accurately determining species mix in the type of wood product. We purchased and tested 10 bags of cypress mulch obtained from six different states. Results indicate that one producer was filling some bags with only 50% cypress and others with no cypress. Consumers may therefore suffer as they receive a lower valued species, whereas honest competitors are also harmed. The wood science community could help regulators and consumers by developing a method by which small particles of wood could be positively identified as to species. Improved methods for species identification are relevant for a wide variety of purposes ranging from identifying consumer products to upholding the U.S. Lacey Act.","PeriodicalId":23620,"journal":{"name":"Wood and Fiber Science","volume":"52 1","pages":"356-364"},"PeriodicalIF":1.4,"publicationDate":"2020-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46093217","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Organic acids are present in many bio-based chemicals suggested as active ingredients for wood preservative formulations, but their effects in wood have not been studied. However, an understanding of their effect in wood is necessary. The aim of this study was to determine the antifungal and wood-preserving activities in vitro of acetic, formic, and propionic acids against the wood-decaying fungi Coniophora puteana, Rhodonia (Poria) placenta, Gloeophyullum trabeum , and Trametes versicolor . Mixes of these three acids were also tested for possible synergetic effects. All the acids and mixtures showed antifungal activity against the pure cultures of wood-decaying fungi. Propionic acid by itself had the best performance, inhibiting at 1 g/L concentration the growth of all the decay fungi by 99-100%. Despite the antifungal activity of the organic acids, the pine sapwood specimens treated with 3% and 6% acid solutions and exposed to decay by C. Puteana and G. trabeum did not differ significantly from the untreated pine. Leaching of the sapwood specimens caused an incremental mass loss of the sapwood specimens. In addition, the leached specimens had a lower mass than the specimens before the acid impregnation, indicating that they were damaged by the acidic chemicals. The presence and acidity of organic acids in wood-derived bio0-based chemicals need to be assessed before they are used as wood preservatives.
{"title":"Antifungal Activity of Organic Acies and Their Impact on Wood Decay Resistance","authors":"Aitor Barbero-López, Mokbul Hossain, A. Haapala","doi":"10.22382/wfs-2020-039","DOIUrl":"https://doi.org/10.22382/wfs-2020-039","url":null,"abstract":"Organic acids are present in many bio-based chemicals suggested as active ingredients for wood preservative formulations, but their effects in wood have not been studied. However, an understanding of their effect in wood is necessary. The aim of this study was to determine the antifungal and wood-preserving activities in vitro of acetic, formic, and propionic acids against the wood-decaying fungi Coniophora puteana, Rhodonia (Poria) placenta, Gloeophyullum trabeum , and Trametes versicolor . Mixes of these three acids were also tested for possible synergetic effects. All the acids and mixtures showed antifungal activity against the pure cultures of wood-decaying fungi. Propionic acid by itself had the best performance, inhibiting at 1 g/L concentration the growth of all the decay fungi by 99-100%. Despite the antifungal activity of the organic acids, the pine sapwood specimens treated with 3% and 6% acid solutions and exposed to decay by C. Puteana and G. trabeum did not differ significantly from the untreated pine. Leaching of the sapwood specimens caused an incremental mass loss of the sapwood specimens. In addition, the leached specimens had a lower mass than the specimens before the acid impregnation, indicating that they were damaged by the acidic chemicals. The presence and acidity of organic acids in wood-derived bio0-based chemicals need to be assessed before they are used as wood preservatives.","PeriodicalId":23620,"journal":{"name":"Wood and Fiber Science","volume":"52 1","pages":"410-418"},"PeriodicalIF":1.4,"publicationDate":"2020-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45488465","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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