燃煤电厂FRP排烟筒筒体对接接头的结构优化

摘要

In order to optimize butt joints of hanging FRP chimney liner in coal-fired power plant, theoretical analysis and tensile tests on the joints were conducted to study the effect of thickness of overlap region, chamfer structure and pre-bonding on the tensile strength, failure loads and failure modes of the joints. The results show that, with the increaseof the thickness of overlap region, the tensile strength increases first and then decreases, and the failure load increases first and then tends to be stable. The chamfer structure and pre-bonding on the end of the joints in the overlap region can improve the tensile strength and failure load of the joints. The joints are damagedwith the increase of the thickness of overlap region, and the failure modes include fiber breaking, overlap region peeling and shear delamination of connections. It is suggested that chamfer structure and pre-bonding should be adopted in the design of FRP chimney joints so as to improve the mechanical be-haviors.%为了优化燃煤电厂悬挂式玻璃纤维增强塑料(FRP)排烟筒筒体之间对接接头连接结构,采用理论计算分析以及对FRP筒体双搭接结构试验件进行拉伸实验的方法,分别研究了搭接区域的厚度、倒角结构和筒体末端预胶接对FRP排烟筒对接接头的拉伸强度、破坏载荷以及破坏形式的影响.结果表明:接头连接试验件的拉伸强度随着搭接区域厚度的增加呈现先增加后减小的趋势,破坏载荷先增加后趋于稳定,当搭接区域厚长比达到8.5%时,拉伸强度和破坏载荷达到最大值;搭接区域倒角结构和接头末端预胶接能够提高接头连接件的拉伸强度和破坏载荷;随着搭接区域厚度的增加,接头连接试验件的破坏形式出现纤维断裂破坏、搭接区域剥离破坏和被连接件的剪切分层破坏.最后,建议FRP排烟筒接头采用倒角和预胶接结构形式,以提高排烟筒的整体受力性能.