在局部分布的负载下对直角截面混凝土的间接拉伸强度进行理论研究
Ziran Wang1, Jialin Xu1, Linhao Sun2
1School of Water Conservancy and Transportation, Zhengzhou University, Zhengzhou 450001, China.
Materials (Basel, Switzerland)
|December 23, 2023
概括
本研究开发了间接拉伸试验的机械模型,并通过模拟和实验验证. 该研究优化了测试参数,如装载宽度和样品尺寸,以准确测量脆性材料的强度.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 固体力学 固体力学是什么
背景情况:
- 间接拉伸试验对于评估脆性材料特性至关重要.
- 精确确定拉伸强度对于材料设计和安全至关重要.
- 现有的模型可能无法完全捕捉间接拉伸性试验中的应力分布的复杂性.
研究的目的:
- 为矩形块的间接拉伸试验建立机械分析模型.
- 在局部分布的负载下获得应力分布的理论解决方案.
- 为了研究装载宽度和长度与高度比对测量拉伸强度的影响.
主要方法:
- 基于弹性力学理论的分析模型的开发.
- 在矩形块中推导应力分布的理论解决方案.
- 理论结果与有限元模拟和实验分离试验的比较.
主要成果:
- 通过有限元和实验数据验证了理论解决方案.
- 增加的装载宽度提高了测量的抗拉强度,稳定了增长速度.
- 最佳的长度与高度比 (约为0.85) 确保中央裂启动,以准确测量强度.
结论:
- 拟议的分析解决方案准确地预测了间接拉力测试中的拉力强度.
- 负载宽度和长度对高度比率显著影响测量的拉伸强度和裂位置.
- 对于可靠的测试,建议使用特定的参数范围,特别是长度与高度的比率.
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