摘要
提出一种新型的采用预应力钢板箍(PSJ)和碳纤维布(CFRP)复合加固钢筋混凝土(RC)墩柱加固方法(简称PSJ-CFRP)。为验证该新型加固技术的可行性和有效性,进行了8个足尺圆形墩柱轴压性能试验,研究参数包括不同加固方法(PSJ、CFRP和PSJ-CFRP)、钢板箍预应力水平、PSJ与CFRP加固配箍特征值等,比较分析采用不同加固方式加固试件的加固效果、破坏形态和承载力等,研究了PSJ-CFRP复合加固RC墩柱的受压机理,钢板箍预应力度、PSJ与CFRP加固配箍特征值等关键参数对试件轴压性能的影响和规律。试验结果验证了PSJ-CFRP复合加固技术的有效性,CFRP与钢板箍协同工作、优势互补,既提高了试件的承载能力,又改善了试件的变形性能,加固试件呈现延性破坏特征。采用CFRP加固的试件,试件的承载能力得到提高,但变形能力降低,呈现脆性的破坏特征。在相同加固配箍特征值下,减小加固箍板净间距能取得更好的加固效果。在试验和理论分析的基础上,提出了PSJ-CFRP复合加固RC墩柱轴向受压承载力计算公式,能较好地预测加固墩柱的轴心受压承载力。
A novel strengthening method for RC pier columns using a prestressed steel jacket(PSJ) and carbon fiber reinforced plastic(CFRP) is proposed. To verify the feasibility and effectiveness of the new strengthening method, eight full-scale circle pier columns were used to investigate the axial compression performance. The main parameters included different strengthening methods(PSJ, CFRP, and PSJ-CFRP), and the prestress level of the steel jacket, strengthening the characteristic values for PSJ and CFRP. A comparative analysis was performed on the reinforcement effect, failure mode, and bearing capacity of the specimens strengthened using different strengthening methods. The compression mechanism of the PSJ-CFRP composite strengthened the RC pier column;furthermore, the influence and law of the prestress level of the steel jacket, as well as the strengthening characteristic values of the PSJ and CFRP on the axial compression performance, were investigated. The test results verify the effectiveness of the PSJ-CFRP composite strengthening technology, achieving the advantages of both CFRP and steel jackets, improving not only the load-bearing capacity of the specimen but also the deformation performance of the specimen. The strengthened specimens failed in ductile failure mode. The load-bearing capacity of the specimens strengthened with CFRP is improved, but the deformation capacity is reduced. The failure mode has the characteristic of brittle failure. Under the same strengthening characteristic value, reducing the net spacing of the reinforcement jacket can achieve a better reinforcement effect. Based on experimental and theoretical analyses, a formula for calculating the axial compressive bearing capacity of RC pier columns strengthened with PSJ-CFRP is proposed, which can accurately predict the axial compressive bearing capacity of the strengthened pier columns.
作者
黄群贤
郭子雄
陈志超
HUANG Qun-xian;GUO Zi-xiong;CHEN Zhi-chao(School of Civil Engineering,Huaqiao University,Xiamen 361201,Fujian,China;Key Laboratory of Structural Engineering and Disaster Prevention of Fujian Province,Huaqiao University,Xiamen 361201,Fujian,China)
出处
《中国公路学报》
EI
CAS
CSCD
北大核心
2022年第2期136-145,共10页
China Journal of Highway and Transport
基金
国家自然科学基金项目(51878304)。
关键词
桥梁工程
RC墩柱
轴压性能试验
预应力钢板箍
碳纤维布
复合加固
bridge engineering
RC piers
axial compression performance test
prestressed steel jacket(PSJ)
carbon fiber reinforcement plastic
composite strengthening
