增强塑料复合管损伤失效机理及寿命预测方法研究

Reinforced thermoplastic pipe (RTP) is a new plastic-matrix steel composite pipe developed in China recently. RTP consists of thermoplastic material matrix and a reticular skeleton sandwiched in the middle, in which the skeleton is formed by cross-wound high-strength steel wires or fibers tightly integrated with the matrix. RTP possesses good material properties, such as strong load-carrying capacity, good corrosion resistance, and wear-resistance, which makes them develop quickly at home and abroad. Because the researches and developments on RTP started in the late 1990s, many basic researches need to be carried out. The applicant found that the viscoelastic properties and intermediate enhancement skeleton structure have a significant influence on the mechanical response characteristics of RTP in his postdoctoral research. Considering the above factors and conducting the basis of theoretical analysis, numerical simulation and experimental studies, the damage failure mechanism, life prediction and optimum design methods of the RTPs will be investigated. This project will further improve the basic theory and the design capacity of the RTPs, reduce production costs and energy consumption, and provide technical support for large-scale application of the RTPs.

增强塑料复合管（RTP）是适应低碳经济发展需求的新型节能环保复合管。它有效地将金属（纤维）的高强度和塑料的耐腐蚀性能融为一体，具有性价比高、承载能力强、使用年限长，耐腐蚀、耐磨损、重量轻、水阻小等优点，目前正在国内外得到了快速地发展和广泛地应用。但是由于RTP研发90年代末期才开始起步，许多基础性研究尚待开展。本项目申请者在博士、博士后的研究中，发现基体材料的粘弹性性能和中间增强骨架的结构形式对RTP的力学响应特性有显著影响。此项研究在考虑上述因素的基础上，通过理论分析、数值模拟和实验研究，进行RTP损伤失效机理、寿命预测和优化设计方法的研究，将进一步完善RTP基础理论，提高我国复合管道的设计能力，降低生产成本，实现节能降耗，为RTP的大规模推广应用提供技术支撑。

本项目将增强塑料复合管（RTP）看作是由不同性质单层壳叠合而成的复合结构，提出了不同温度RTP爆破压力预测模型，通过不同温度下的短时爆破试验，验证了提出模型的有效性。考虑钢丝/HDPE复合材料层的四种失效模式，应用Hashin失效准则，结合材料细观损伤力学，提出了RTP损伤演化预测模型，通过试验验证了损伤演化预测模型的正确性。基于RTP的失效形式和损伤失效机理，结合聚合物材料的时温等效原理，提出了RTP寿命预测方法，并深入揭示RTP影响寿命的主要因素，通过RTP80 ℃热水浴中的长期静液压试验，验证了提出寿命预测方法的有效性。以强度、材料成本为优化目标，提出了RTP优化设计方法，通过试验研究，验证了优化设计方法的准确性。