Wrapping LVL as a wood-only timber frame joint inspired by the model of trees' stem-branch junction

将 LVL 包裹为纯木材的木框架接头，其灵感源自树木的茎-枝连接处模型

• 批准号: 22K20463
• 负责人: Firas HAWASLY
• 金额: $ 0.92万
• 依托单位: Akita Prefectural University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Research Activity Start-up
• 财政年份: 2022
• 资助国家: 日本
• 起止时间: 2022-08-31 至 2024-03-31
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-22K20463/
• 关键词: Wrapping LVL; Veneer reinforcement; Stem-branch junction; Timber frame joint; Wood-only joint; Bio-Inspired

The performed simplified experiments of adding 45 degrees cross-laminated veneer layers as outer reinforcements to three sides of the flat-wise loaded laminated-core material with a thickness of 8% of the total depth, showed the significant enhancement in moment capacity, doubling the performance of the unreinforced core material in flat-wise and edge-wise loading conditions and slightly surpassing the performance of solid wood.These initial findings promise to introduce enhanced bent-laminated elements capable of seamlessly transferring loads between two linear sections adequately and homogeneously and approaching the intended aim of a structurally sound, wood- only, moment-resistant constructional application at timber joints. However, the intended continuous wrapping approach of the addressed application proved to be technically challenging, specifically on curved surfaces; hence, much simpler applications of wrapped bent veneers with the same intended performance have been developed. Furthermore, regarding the parameters of adhesive type, thickness, wrapping angle, and material of the reinforcement layers, a specially developed shear/tension testing jig was manufactured to achieve the optimal combination. The fixture was adapted from the Arcan et al. shear fixture; ranging from pure shear to pure tension in 15 degrees increments and at variable thicknesses, and will facilitate the analytical parametric design of the desired performance.

将45度交叉层压单板层作为外部加强件添加到厚度为总深度的8%的平向加载层压芯材料的三个侧面的简化实验表明，弯矩承载力显著提高，使未增强芯材料在平面方向和边缘方向的性能加倍，明智的加载条件和略优于实木的性能。这些初步的研究结果有望引入增强弯曲，能够在两个线性部分之间充分且均匀地无缝地传递载荷的层压元件，在木材接缝处的抗弯矩建筑应用。然而，所述应用的预期连续包裹方法被证明在技术上具有挑战性，特别是在弯曲表面上;因此，已经开发了具有相同预期性能的包裹弯曲单板的更简单的应用。此外，关于粘合剂类型，厚度，包裹角度，和加强层的材料的参数，一个专门开发的剪切/拉伸测试夹具制造，以实现最佳组合。该夹具改编自Arcan等人的剪切夹具;范围从纯剪切到纯拉伸，增量为15度，厚度可变，将有助于所需性能的分析参数设计。

项目成果

The reinforcement effect of adding cross-laminations to the sides of laminated veneer material

层压单板材料侧面添加交叉层压板的加固效果

• 发表时间: 2023
• 作者: Firas HAWASLY;Koji ADACHI
• 通讯作者: Koji ADACHI