高强钢绞线网/ECC抗弯加固无损RC梁数值模拟及理论分析  

Numerical simulation and theoretical analysis of flexural strengthening of RC beams with high-strength steel strand mesh/ECC

作　　者：李可[1] 王少华 郑书宁 范家俊[1] 朱俊涛[1] LI Ke;WANG Shaohua;ZHENG Shuning;FAN Jiajun;ZHU Juntao(School of Civil Engineering,Zhengzhou University,Zhengzhou 450001,China;Yangquan Market Supervision Management Bureau,Yangquan 045000,China)

机构地区：[1]郑州大学土木工程学院,郑州450001 [2]阳泉市市场监督管理局,阳泉045000

出　　处：《复合材料学报》2024年第11期6077-6091,共15页Acta Materiae Compositae Sinica

基　　金：国家自然科学基金面上项目(52378319);国家自然科学基金委河南联合基金(U1804137);国家自然科学基金青年项目(52108183);河南省科技攻关项目(222102320129)。

摘　　要：采用有限元模拟与试验相结合的方法,研究了加固层材料用量、加固材料材性、加固钢筋混凝土(RC)梁特征参数等因素对高强钢绞线网/纤维增强水泥基复合材料(ECC)抗弯加固RC梁受弯性能的影响规律。首先,建立了高强钢绞线网/ECC加固既有无损RC梁有限元分析模型,并与试验结果比较,验证了其准确性和有效性,并采用该模型对关键参数对加固梁受弯性能的影响规律进行系统性分析。结果表明:该加固方法可显著提升RC梁的受弯承载力、刚度、延性,提升幅度分别为7.81%~61.84%、6.35%~40.90%、5.92%~50.16%;随着纵向钢绞线配筋率、加固层厚度和开裂应力的增大,承载力的提升幅度增大,而RC梁纵筋配筋率和截面高度增大会降低承载力的提升幅度;加固层厚度与纵向钢绞线配筋率的增大会增加刚度的提升幅度,而RC梁纵筋配筋率、混凝土强度和截面高度的增大会降低对刚度的提升幅度;延性的提升幅度随着混凝土强度的增大而增加。在此基础上结合相关力学理论,提出抗弯加固界限钢绞线用量计算公式及高强钢绞线网/ECC加固RC梁正截面承载力简化计算公式,与试验及数值模拟结果吻合良好。Using a combination of finite element simulation and experimentation,the impact of reinforcement layer material quantity,properties of reinforcement materials,and characteristic parameters of reinforced concrete(RC)beams on the flexural performance of RC beams strengthened with high-strength steel wire mesh/engineered cementitious composites(ECC)was investigated.Firstly,the finite element(FE)analysis model of existing nondestructive RC beams strengthened with high-strength steel wire mesh/ECC was established,and its effectiveness and accuracy were verified by comparing with the experimental results.The validated FE model was adopted to analyze the influencing factors of flexural performance of strengthened beams systematically.The results indicate that the strengthening method can significantly enhance the flexural bearing capacity,stiffness,and ductility of RC beams,with improvement ranges of 7.81%to 61.84%,6.35%to 40.90%,and 5.92%to 50.16%,respectively.With the increase of longitudinal steel strand reinforcement ratio,thickness and cracking stress of ECC,the promotion range of bearing capacity increases,while the increase of longitudinal steel reinforcement ratio and sec-tion height of RC beams decrease the increment of bearing capacity.The increase of the thickness of ECC and the reinforcement ratio of longitudinal steel strand increase the promotion range of stiffness,but the promotion range decreases with the increment of longitudinal reinforcement ratio,concrete strength and section height of RC beams.The increment of ductility only increases with the increase of concrete strength.On this basis,combined with relevant mechanical theories,the calculation formula for the limit amount of steel strands for flexural strengthening and simplified calculation formulas for the normal-section bearing capacity of RC beams reinforced by high-strength steel wire strand mesh-reinforced ECC are proposed,calculation results are in good agreement with experimental and numerical simulation results.

关 键 词：结构加固 高强钢绞线网/ECC 试验与数值模拟 受弯性能 承载力 刚度 延性 

分 类 号：TU311[建筑科学—结构工程] TB332[一般工业技术—材料科学与工程]