{"title":"树木含水量对动态荷载下树木结构完整性的影响","authors":"Lukas Emmerich, Christian Brischke","doi":"10.5552/drvind.2023.0067","DOIUrl":null,"url":null,"abstract":"The majority of mechanical wood properties are negatively affected by wood moisture within the hygroscopic range, disregarding the stress relaxation of wood at very low moisture contents (MC). In contrast, the structural integrity and thus the brittleness of wood appears to be positively affected by moisture. This study aimed at examining the effect of wood MC on the structural integrity of wood between the oven-dry state and MC well above cell wall saturation (CWS), i.e., at approx. 100 %. For both softwood (Picea abies) and hardwoods (Fagus sylvatica and Quercus robur), the structural integrity was assessed on the basis of the Resistance to Impact Milling (RIM) originating from High-Energy Multiple Impact (HEMI) tests. RIM increased with increasing MC in the hygroscopic range, which might be explained by stress relaxation and ‘gluing effects’ inside the cell wall polymer structure, resulting from a growing network of hydrogen bonds on cell wall level. Increasing MC above CWS caused a slight decrease of RIM in the selected hardwood species, whereas no significant change in RIM was observed when MC varied in the range from CWS to approx. 100 % for the softwood species Norway spruce.","PeriodicalId":11427,"journal":{"name":"Drvna Industrija","volume":null,"pages":null},"PeriodicalIF":0.7000,"publicationDate":"2023-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Utjecaj sadržaja vode u drvu na strukturnu cjelovitost drva pri dinamičkim opterećenjima\",\"authors\":\"Lukas Emmerich, Christian Brischke\",\"doi\":\"10.5552/drvind.2023.0067\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"The majority of mechanical wood properties are negatively affected by wood moisture within the hygroscopic range, disregarding the stress relaxation of wood at very low moisture contents (MC). In contrast, the structural integrity and thus the brittleness of wood appears to be positively affected by moisture. This study aimed at examining the effect of wood MC on the structural integrity of wood between the oven-dry state and MC well above cell wall saturation (CWS), i.e., at approx. 100 %. For both softwood (Picea abies) and hardwoods (Fagus sylvatica and Quercus robur), the structural integrity was assessed on the basis of the Resistance to Impact Milling (RIM) originating from High-Energy Multiple Impact (HEMI) tests. RIM increased with increasing MC in the hygroscopic range, which might be explained by stress relaxation and ‘gluing effects’ inside the cell wall polymer structure, resulting from a growing network of hydrogen bonds on cell wall level. Increasing MC above CWS caused a slight decrease of RIM in the selected hardwood species, whereas no significant change in RIM was observed when MC varied in the range from CWS to approx. 100 % for the softwood species Norway spruce.\",\"PeriodicalId\":11427,\"journal\":{\"name\":\"Drvna Industrija\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.7000,\"publicationDate\":\"2023-06-20\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Drvna Industrija\",\"FirstCategoryId\":\"88\",\"ListUrlMain\":\"https://doi.org/10.5552/drvind.2023.0067\",\"RegionNum\":4,\"RegionCategory\":\"农林科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q4\",\"JCRName\":\"MATERIALS SCIENCE, PAPER & WOOD\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Drvna Industrija","FirstCategoryId":"88","ListUrlMain":"https://doi.org/10.5552/drvind.2023.0067","RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"MATERIALS SCIENCE, PAPER & WOOD","Score":null,"Total":0}
Utjecaj sadržaja vode u drvu na strukturnu cjelovitost drva pri dinamičkim opterećenjima
The majority of mechanical wood properties are negatively affected by wood moisture within the hygroscopic range, disregarding the stress relaxation of wood at very low moisture contents (MC). In contrast, the structural integrity and thus the brittleness of wood appears to be positively affected by moisture. This study aimed at examining the effect of wood MC on the structural integrity of wood between the oven-dry state and MC well above cell wall saturation (CWS), i.e., at approx. 100 %. For both softwood (Picea abies) and hardwoods (Fagus sylvatica and Quercus robur), the structural integrity was assessed on the basis of the Resistance to Impact Milling (RIM) originating from High-Energy Multiple Impact (HEMI) tests. RIM increased with increasing MC in the hygroscopic range, which might be explained by stress relaxation and ‘gluing effects’ inside the cell wall polymer structure, resulting from a growing network of hydrogen bonds on cell wall level. Increasing MC above CWS caused a slight decrease of RIM in the selected hardwood species, whereas no significant change in RIM was observed when MC varied in the range from CWS to approx. 100 % for the softwood species Norway spruce.
期刊介绍:
"Drvna industrija" ("Wood Industry") journal publishes original scientific and review papers, short notes, professional papers, conference papers, reports, professional information, bibliographical and survey articles and general notes relating to the forestry exploitation, biology, chemistry, physics and technology of wood, pulp and paper and wood components, including production, management and marketing aspects in the woodworking industry.