机构地区: 广东工业大学土木与交通工程学院
出 处: 《公路交通科技》 2013年第8期70-74,共5页
摘 要: 针对国内体外预应力研究较落后的现状,进行了6根体外预应力筋和2根普通钢筋混凝土简支T梁正截面静力加载试验,对其受力过程、破坏形态、承载力、延性和变形情况进行了分析。试验结果表明,体外预应力筋可以大幅度提高混凝土梁的开裂荷载、屈服荷载和极限荷载,延迟裂缝开展,改善梁的正常使用状态;直线束双转向块力筋形式对试件抗裂最为有利,双折线力筋对屈服荷载提高幅度最大,转向块个数能显著提高试件的极限荷载;体外预应力能有效减小构件的变形,延缓钢筋屈服,构件的整体刚度显著提高;体外预应力筋不同布置形式对试件极限承载力和挠度变形影响较大,而预应力张拉方式影响相对较小。 To cope with the present domestic backward research situation of external prestressing, 6 external tendons and 2 ordinary reinforced concrete T -section simple beams are designed and applied for static loading test. The stressing process, failure mode, bearing capacity, ductility and deformation are studied. The test result shows that (1) external tendons can significantly enhance cracking load, yield load and ultimate loads of concrete beams and postpone crack propagation and improve the state of normal service performance of concrete beams. (2) Linear double deviation blocks external prestressing is most favorable for anti -crack of the beams, double broken line external prestressing is most effective to increase yield load, and the number of deviation block can significantly increase the ultimate loads of the beams. (3) external prestressing can reduce deformation of the structure and increase yield load, and can effectively increase the rigidity of beams; ( 4) different tendon configuration can significantly influence the ultimate bearing capacity and deformation, which are slightly influenced by stretching mode.