文献类型：期刊文献

英文题名：Evolution of interlaminar shear failure in CLT: Insights from theoretical calculation, acoustic emission, and microstructural analysis

作者：Qu, Jialei[1] Gong, Yingchun[1,2] Li, Mingyue[1,2] Ren, Haiqing[1,2]

第一作者：Qu, Jialei

通信作者：Gong, YC[1]

机构：[1]Chinese Acad Forestry, Res Inst Wood Ind, Beijing 100091, Peoples R China;[2]Collaborat Innovat Ctr Efficient Proc & Utilizat F, Nanjing 210037, Jiangsu, Peoples R China

年份：2025

卷号：470

外文期刊名：CONSTRUCTION AND BUILDING MATERIALS

收录：;EI(收录号：20250917957356);Scopus(收录号：2-s2.0-85218636351);WOS:【SCI-EXPANDED(收录号:WOS:001435389800001)】；

基金：This study was supported by the National Natural Science Foundation of China Youth Project "Correlation Mechanism Between the Mechanical Response and Microstructure Damage of Cross-laminated Timber Under Compression Perpendicular to the Grain" (32401509) ; the National Key Research and Development Program of China "Key Technology for the Manufacture and Evaluation of Structural Large-size Laminated Wood" (2021YFD2200605) ; and the Shandong Province Science and Technology Small- and Medium-sized Enterprise Innovation Capability Improvement Project (2023TSGC0821) .

语种：英文

外文关键词：Cross-laminated timber; Interlayer shear strength; Acoustic emission technology; Microstructure; Failure damage

摘要：Cross-laminated timber (CLT) has been recognized as an alternative to traditional construction materials. In this study, CLT was prepared using plantation-grown Chinese fir and a one-component polyurethane adhesive. The theoretical calculation of shear stress in CLT was conducted to establish a basis for testing its interlaminar shear strength. The mechanisms by which layup grade and gap width affect interlayer shear strength in CLT were explored. Scanning electron microscopy was used to examine the microstructural failure characteristics of interlayer shear in CLT were investigated. Acoustic emission (AE) technology evaluated damage evolution and failure modes during interlayer shear loading. The results showed that interlaminar shear stress in CLT was related to the number of CLT layers and the ratio of the elastic modulus of the parallel and vertical layers E1/E2. Interlayer shear stress in three- and five-layer CLT was 0.92 and 0.81 times that in glulam, respectively. Significant effects of the gaps on interlayer shear strength in CLT were observed. When the gap in the parallel layer was increased from 0 to 4 mm, the interlayer shear strength was reduced by 8.10%. Interlayer shear failure modes in CLT were primarily identified as rolling shear failure in the vertical layer and tensile fracture in the bottom layer. Rolling shear failure in the vertical layer mainly occurred at the earlywood-latewood interface and exhibited discontinuous failure in the wood ray direction. Variations in AE energy accurately reflect the evolution of CLT interlayer shear damage. During the deformation stage, AE energy signals were low, as wood fiber bundles buckled and tensile microcracks began to form. During the crack propagation stage, cumulative AE energy increased linearly, and shear crack signals with high RA and low AF values increased. During the failure stage, AE energy signals peaked locally; shear crack signals with high RA and low AF values comprised 25.99 % of the total. The fracture mode of CLT changed from tension-type failure to tension-shear composite failure.