（1 上海市建筑科学研究院有限公司 上海市工程结构安全重点实验室， 上海 200032；2 南京工业大学土木工程学院， 南京 211816）

［摘要］为研究内嵌CFRP筋加固木梁在长期荷载作用下的受力性能，设计并制作了3个木梁试件，开展了6年的持荷试验，持续测试了木梁的跨中挠度变化和纯弯段木材的蠕变发展，并记录了环境温湿度变化对木材中和轴位置应变增量的影响。结果表明，对比木梁和加固木梁的初始缺陷均对其长期性能有重要影响，跨中不存在初始缺陷的加固木梁的挠度小于未加固对比木梁；而跨中存在明显初始缺陷的加固木梁的挠度高于未加固对比木梁，并在跨中木节周围出现了明显裂缝。根据试验结果对经典蠕变模型中的材料参数进行了拟合，拟合后的模型预测的木梁跨中挠度与试验结果比较吻合。

［关键词］木梁； 内嵌CFRP筋； 长期性能； 持荷试验； 蠕变模型

中图分类号：TU366-2，TU317-1文献标识码：A文章编号：1002-848X(2020)05-0015-05

Experimental study on mechanical behavior of timber beams reinforced by near-surface mounted  CFRP reinforcement under 6-year sustained loading

Wang Zhuolin1, Liu Weiqing2, Xu Qingfeng1, Wang Mingqian1, Zhang Fuwen1, Chen Xi1

(1 Shanghai Key Laboratory of Engineering Structure Safety, SRIBS, Shanghai 200032, China; 2 College of Civil Engineering, Nanjing Tech University, Nanjing 211816, China)

Abstract:To investigate the long-term behavior of timber beams reinforced by near-surface mounted (NSM) CFRP reinforcement, 3 timber beam specimens were designed and tested under 6-year sustained loading. Mid-span deflection and creep development of the pure bending section were continuously monitored, and the effect of ambient temperature and humidity on strain increment was recorded. Test results indicate that the initial defects  play an important role in the long-term behavior of timber beams including the control and reinforced timber beam. Deflection of reinforced beam without initial defects at mid-span was less than that of the unreinforced control beam, and deflection of reinforced beam with initial defects at mid-span was much larger than that of the unreinforced control beam. Cracks occurred around the knot at mid-span of the reinforced beam. The material parameters of some classical creep models were fitted according to the test results, and the mid-span deflection predicted by the fitted model is in good agreement with the test results.

Keywords:timber beam; near-surface mounted CFRP bar; long-term behavior; sustained loading; creep model

*国家重点研发计划项目（2017YFC0702900），上海市优秀技术带头人计划项目（18XD1422800）。

作者简介：王卓琳，博士，正高级工程师，Email：wzllzw@163.com。