CFRP筋拉伸强度预测模型评价及应用
2017-10-17杨勇新岳清瑞
王 彬,杨勇新,岳清瑞,曾 滨
(中冶建筑研究总院有限公司,北京 100088)
CFRP筋拉伸强度预测模型评价及应用
王 彬,杨勇新,岳清瑞,曾 滨
(中冶建筑研究总院有限公司,北京 100088)
在初步建立CFRP筋拉伸强度预测模型基础上,对该模型典型因子影响材料强度权重进行研究评价,根据结果提出CFRP筋制备过程中强度补偿机制。结果表明:典型因子碳纤维拉伸强度(σf)和体积分数(Vf)对CFRP筋拉伸强度影响最为显著(影响率为39.1%~46.7%和43.5%~52.6%),是决定CFRP筋拉伸性能的最重要因素。公称直径(D)对CFRP筋拉伸强度存在一定程度影响(影响率7.1%~15.4%)。基体树脂强度(σm)对CFRP筋拉伸强度影响不明显(影响率0.3%~1.0%),相比其他三种因素,可近似忽略。依据预测模型典型因子强度补偿规律,可较方便推测CFRP筋组分碳纤维强度及体积分数参数。
CFRP筋;拉伸强度;预测;评价
Abstract: Based on the prediction formula of tensile strength for CFRP bars, weight of influence of the typical factors on material strength was evaluated, and the mechanism of intensity compensation in the process of preparing CFRP bar was proposed. The results show that the effect of typical factors of carbon fiber tensile strength and volume fraction effect on the tensile strength of CFRP bars is most significant (influence rate:39.1%-46.7% and 43.5-52.6%). They are the most important factors that determine the tensile properties of CFRP bars. Nominal diameter has a certain effect on the tensile strength of CFRP bars (influence rate: 7.1%-15.4%). Influence of resin matrix strength on the tensile strength of the CFRP bar is not obvious (influence rate: 0.3%-1.0%). Compared to the other three factors, the influence of the tensile strength of resin can be nearly neglected. According to the intensity compensation rule of the typical factors, the strength and volume fraction of carbon fiber in CFRP bars can be easily inferred.
Keywords:CFRP bars;tensile strength;prediction;evaluation
碳纤维增强复合材料筋(CFRP筋)具有优异的力学性能和耐腐蚀特性,在桥梁、岩土、隧道、岛礁等工程建设领域,作为新型结构材料,可部分代替钢筋,应用前景良好,受到国内外专家学者的普遍关注[1-3]。
目前我国CFRP筋产品规格型号繁多,质量悬殊较大,深入推进其在工程建设领域的规范、安全应用具有诸多困难[4-5]。
基于经典复合材料混合理论,结合实验研究提出的CFRP筋拉伸强度预测模型σ=0.95×[σfVf+σm(1-Vf)]-B×D[6],为工程设计应用提供了材料制备的有效指导。在此基础上,本工作借助大数据分析手段,结合归一化处理方法,对该模型的典型因子影响权重进行研究评价,提出典型因子影响的CFRP筋强度补偿机制及产品组分参数预测评估方法建议,以期为调控低成本高强度质量稳定的CFRP筋制备生产以及工程应用的高效检测评估提供理论基础。……
