Abstract The well-established benefits of compressive residual stresses over the fatigue lifetime constantly motivate engineers to scrutinize these trapped stresses in mechanical/civil structures. This research deals with characterization of thermal residual stresses in fiber reinforced polymer (FRP) tubes. Three important thermo-mechanical parameters, namely “cooling temperature”, “CNT reinforcement” and “tube size” are taken into account with the aim of achieving optimum design in manufacturing of FRP tubes. The work includes experimental evaluation of residual stresses coupled with developing a MATLAB programming code and performing a thorough finite element (FE) analysis. After fabricating several hybrid FRP tubes with respect to the mentioned parameters, we measured residual stresses conducting “slitting” semi-destructive method. The impact of either of parameters is then examined and some key points are suggested regarding controlling residual stress in FRP structures. The outcomes of this work suggest that slitting method can practically provide access to the in-depth distribution and through thickness of trapped stresses in the FRP laminates with a good accuracy. It is also underscored that studied parameters could play a crucial role in creation of thermal residual stresses.

中文翻译：

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确定热机械因素对圆柱形复合管残余应力的影响：实验和计算分析

摘要 压缩残余应力在疲劳寿命期间的公认优势不断促使工程师仔细检查机械/土木结构中的这些被困应力。本研究涉及纤维增强聚合物 (FRP) 管中热残余应力的表征。三个重要的热机械参数，即“冷却温度”、“CNT 增强”和“管尺寸”被考虑在内，以实现 FRP 管制造的最佳设计。工作包括残余应力的实验评估，以及开发 MATLAB 编程代码和执行彻底的有限元 (FE) 分析。在根据上述参数制造了几个混合 FRP 管后，我们通过“切割”半破坏性方法测量了残余应力。然后检查任一参数的影响，并就控制 FRP 结构中的残余应力提出了一些关键点。这项工作的结果表明，切开方法实际上可以以良好的精度获得 FRP 层压板中被困应力的深度分布和整个厚度。还需要强调的是，所研究的参数在产生热残余应力方面可能起着至关重要的作用。