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（1 上海市建筑科學(xué)研究院有限公司 上海市工程結(jié)構(gòu)安全重點(diǎn)實(shí)驗(yàn)室， 上海 200032；2 南京工業(yè)大學(xué)土木工程學(xué)院， 南京 211816）

［摘要］為研究?jī)?nèi)嵌CFRP筋加固木梁在長(zhǎng)期荷載作用下的受力性能，設(shè)計(jì)并制作了3個(gè)木梁試件，開展了6年的持荷試驗(yàn)，持續(xù)測(cè)試了木梁的跨中撓度變化和純彎段木材的蠕變發(fā)展，并記錄了環(huán)境溫濕度變化對(duì)木材中和軸位置應(yīng)變?cè)隽康挠绊憽＝Y(jié)果表明，對(duì)比木梁和加固木梁的初始缺陷均對(duì)其長(zhǎng)期性能有重要影響，跨中不存在初始缺陷的加固木梁的撓度小于未加固對(duì)比木梁；而跨中存在明顯初始缺陷的加固木梁的撓度高于未加固對(duì)比木梁，并在跨中木節(jié)周圍出現(xiàn)了明顯裂縫。根據(jù)試驗(yàn)結(jié)果對(duì)經(jīng)典蠕變模型中的材料參數(shù)進(jìn)行了擬合，擬合后的模型預(yù)測(cè)的木梁跨中撓度與試驗(yàn)結(jié)果比較吻合。

［關(guān)鍵詞］木梁； 內(nèi)嵌CFRP筋； 長(zhǎng)期性能； 持荷試驗(yàn)； 蠕變模型

中圖分類號(hào)：TU366-2，TU317-1文獻(xiàn)標(biāo)識(shí)碼：A文章編號(hào)：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

*國(guó)家重點(diǎn)研發(fā)計(jì)劃項(xiàng)目（2017YFC0702900），上海市優(yōu)秀技術(shù)帶頭人計(jì)劃項(xiàng)目（18XD1422800）。

作者簡(jiǎn)介：王卓琳，博士，正高級(jí)工程師，Email：wzllzw@163.com。