使用自动化系统对orthotropic材料进行全面的爬行符合性表征
1ETH Zurich, Institute for Building Materials, HIF E 27, Laura-Hezner-Weg 7, CH-8093 Zurich, Switzerland.
概括
这项研究开发了一个自动化系统来测量木材.
科学领域:
- 材料科学 材料科学 材料科学
- 木制机械 木制机械
- 粘性弹性 粘性弹性
背景情况:
- 对于像挪威松树这样的适应湿气的材料,Creep合规数据在各种气候和解剖学方向上是有限的.
- 现有的木材模拟模型往往通过忽略气候影响或比例缩放缺失数据来过度简化爬行行为.
研究的目的:
- 开发一种自动化,计算机控制的气候化爬行架,用于全面的依赖湿度的粘弹性和机械吸收评估.
- 实验性地确定挪威松树在所有解剖学方向上的完整的正向爬行合规张量,考虑到负载不对称.
主要方法:
- 使用了一种全新的自动爬行架,同时测试张力,压缩和剪切样品.
- 采用数字图像相关性 (DIC) 来测量爬行菌株.
- 在65%的相对湿度下确定了所有九个独立的爬行合规组件.
主要成果:
- 发现负载不对称效应是显著的,高达18%.
- 确定的爬行合规张量与弹性合规张量不成比例.
- 确定了四个基本组成部分,以表示合规张量的完整正向性,至少可以通过两个实验实现.
结论:
- 开发的系统可以在不同的条件下详细描述木材的粘弹性行为.
- 这些发现强调了在木材爬行模型中考虑载荷方向和水分含量的重要性.
- 简化的一组实验可以捕捉到木材的爬行顺服的基本正向性质.
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