CFRP加固RC简支T梁桥受力性能试验研究

为深入研究粘贴碳纤维布加固钢筋混凝土T梁桥的加固效果,结合某桥梁大修工程,通过在简支T梁梁底粘贴4层碳纤维布以提高其正截面承载能力.为检验加固效果,分别在加固前后对试验孔进行荷载试验,加固前后均采用两辆重约330kN的同型号三轴载重汽车作为试验荷载,重点检测了加固前后主梁跨中挠度、梁底混凝土及碳纤维布应变以及裂缝扩展情况.荷载试验结果表明,在简支钢筋混凝土梁桥上粘贴碳纤维布可有效抑制混凝土开裂,增加破损主梁的抗弯刚度,提高上部结构整体受力的能力.

Research on behaviors of simply-supported reinforced concrete T-beam bridge strengthened with CFRP sheets

To research into the structural behavior of an aging reinforced concrete T-beam bridge strengthened with CFRP (carbon fiber reinforced polymer) sheets, combining with the project of bridge strengthening, four piles of CFRP sheets were bonded at the bottom of the beams to strengthen the T-beam bridge for improving the load-bearing ability of positive section. Load tests were conducted on the performance of this bridge before and after the installation of the CFRP system. Two three-axle trucks of the same type were used in the load tests. Average weight of each truck is approximately 330 kN. Strain data of concrete at the bottom of the beam and CFRP sheets, mid-span deflection of main beam and crack width were collected. Tests results indicate that strengthening simply-supported reinforced concrete bridge with externally bonded CFRP sheets can not only reduce the width of cracks and strains in concrete, but also increase the flexural stiffness of the cracked main beam, and improve the transverse load distribution in superstructure.