摘要
为研究混杂纤维(钢纤维/聚丙烯纤维)高性能混凝土深梁的斜截面抗裂度,采用正交试验法设计了18组混杂纤维高性能混凝土深梁试件和2组未掺纤维的普通高性能混凝土深梁对比试件.通过静载作用下的受剪试验,探讨了钢纤维的特征参数(类型、体积率、长径比)、聚丙烯纤维体积率、水平分布钢筋配筋率及竖向分布钢筋配筋率等6个因素对高性能混凝土深梁斜截面抗裂度的影响,通过正交试验的直观分析法比较了各个因素对斜截面抗裂度的影响顺序.试验结果表明:掺入适量的混杂纤维(钢纤维/聚丙烯纤维)后,无腹筋高性能混凝土深梁斜截面抗裂度提高幅度可达34.9%,有腹筋高性能混凝土深梁斜截面抗裂度提高幅度可达83.8%.基于现行规范提出了与钢纤维部分增强钢筋混凝土深梁相衔接的混杂纤维(钢纤维/聚丙烯纤维)高性能混凝土深梁斜截面抗裂度的计算公式,可为工程设计提供参考.
In order to study diagonal section crack resistance of hybrid fiber reinforced high performance concrete （HPC）deep beams,18 different groups of deep beams with steel fiber and polypropylene fiber and 2 groups HPC deep beams without fiber were made according to orthogonal test method. The effects of 6 factors on diagonal section crack resistance of HPC deep beams were explored through the shear tests under dead load. The contributory factors such as the characteristic parameters of steel fiber （types, volume fraction, aspect ratio）, the volume fraction of polypropylene fiber, the ratio of web horizontal reinforcement and the ratio of web vertical reinforcement were compared by direct-viewing analysis of the orthogonal experiment. The results show that hybrid fiber can be used to greatly increase the diagonal section crack resistance of HPC deep beams. The diagonal section crack resistance of HPC deep beams without web reinforcement is increased by 34. 9% while diagonal section crack resistance of HPC deep beams with web reinforcement is increased by 83.8%. Based on current code, a formula for calculating the diagonal section crack resistance of hybrid fiber reinforced HPC deep beams is proposed coordinating with steel fiber reinforced concrete deep beams, which can be taken as a reference in engineering design.
出处
《武汉工程大学学报》
CAS
2013年第3期8-12,共5页
Journal of Wuhan Institute of Technology
基金
湖北省教育厅青年科学基金(B200514003)
武汉工程大学科学研究基金(13105021)
关键词
混杂纤维
正交试验法
受剪试验
剪切初裂强度
计算公式
hybrid fiber
orthogonal test method
shear test
diagonal cracking strength
calculation formula
