预应力碳纤维板加固梁桥长期徐变性能的试验研究

Experimental Study on Long-term Creep Behavior of Beam Bridge Strengthened with Prestressed CFRP Plate

采用自主研发的一套预应力碳纤维板张拉和锚固机械装置,在室内12 m长的H型钢梁上对碳纤维板进行了预应力张拉和锚固试验,并运用光纤光栅传感器(FBG)对预应力碳纤维板应变进行了长达一年的观测;在室内试验研究的基础上,将该套加固技术应用到实体梁桥加固工程中(湘潭解放桥和洙津渡大桥),并对两座被加固梁桥预应力碳纤维板的长期应变进行了观测和分析。室内试验及实体加固工程应用结果表明:用该套预应力碳纤维板加固技术在长期预应力和外界荷载作用下,锚具具有良好的机械锚固性能,碳板几乎不产生滑移,其预应力损失也非常小,对桥梁长期加固效果没有影响。

The prestressed tensioning and anchorage experiment of CFRP plate on a 12 m long steel H-beam is done by using a set of independent developed prestressed CFRP plate tensioning and anchoring device, and the strain of the prestressed CFRP plate is observed for up to one year by using FBG sensor. On the basis of indoor experiment, the reinforcement technology is applied to the real beam bridge reinforcement projects （Xiangtan Jiefang bridge and zhujindu bridge）, and the long-term creeps of the prestressed CFRP plates on the reinforced bridges are observed and analysed. The results of laboratory tests and the reinforcement project application show that （ 1 ） after using the technology of prestressed CFRP plate reinforcement, under long- term prestress and external loads, the mechanical property of the anchorage is very good, the CFRP plates produce almost no slip, and the loss of prestress is also very small, which has little adverse influence on the strengthened structure.