884aa四虎影成人精品,99久久国产综合精品女图图等你,97在线观看永久免费视频,久久精品国产精品亚洲38,ⅵdeodesetv性欧美

（北京工業(yè)大學(xué)城市與工程安全減災(zāi)教育部重點(diǎn)實(shí)驗(yàn)室， 北京 100124）

［摘要］為研究半預(yù)制HRB600級(jí)鋼筋鋼纖維高強(qiáng)混凝土梁（簡(jiǎn)稱半預(yù)制梁）的受彎性能，設(shè)計(jì)了5根半預(yù)制梁進(jìn)行了三分點(diǎn)單調(diào)加載試驗(yàn)，分析了預(yù)制外殼混凝土強(qiáng)度、鋼纖維摻量以及鍵槽間距等因素對(duì)半預(yù)制梁承載力、撓度、裂縫發(fā)展變化規(guī)律的影響，并與現(xiàn)澆HRB600級(jí)鋼筋高強(qiáng)混凝土梁（簡(jiǎn)稱現(xiàn)澆梁）進(jìn)行了比較。結(jié)果表明，半預(yù)制梁與現(xiàn)澆梁表現(xiàn)出相同的受力特點(diǎn)和變形特征；預(yù)制外殼加入鋼纖維可提高試驗(yàn)梁的開裂荷載，改善延性，減小裂縫寬度；提高預(yù)制外殼混凝土強(qiáng)度可提高試驗(yàn)梁的極限承載力；設(shè)置鍵槽，可提高梁的極限承載力，延緩剛度退化，改善延性；設(shè)置鍵槽的半預(yù)制梁在受彎荷載下的承載力、裂縫寬度、撓度可按《纖維混凝土結(jié)構(gòu)技術(shù)規(guī)程》（CECS 38∶2004） 計(jì)算。

［關(guān)鍵詞］半預(yù)制；鋼纖維； 高強(qiáng)混凝土；受彎性能；鍵槽

中圖分類號(hào)：TU375-1文獻(xiàn)標(biāo)識(shí)碼：A文章編號(hào)：1002-848X(2021)05-0048-06

Experimental study on flexural behavior of semi-precast steel fiber reinforced high-strength concrete beams with HRB600 steel bars

ZHANG Jianwei, LIU Jiao, CAI Ruxing, ZHANG Deli

（Key Laboratory of Urban and Engineering Security Disaster of China Ministry of Education, Beijing University of Technology, Beijing 100124, China）

Abstract:In order to study the flexural behavior of semi-precast steel fiber reinforced high-strength concrete beams with HRB600 steel bars(semi-precast beams), five semi-precast beams were designed and the three-point monotonic load test were carried out. The effects of precast shell concrete strength, steel fiber content and keyway spacing on the bearing capacity, deflection and crack development of semi-precast beams were analyzed, and the test results were compared with cast-in-place high-strength concrete beams with HRB600 steel bars (cast-in-place beams). The results show that the semi-precast beams exhibite the same mechanical performance and deformation characteristics as the cast-in-place beams; the addition of steel fiber  to the prefabricated shell can  increase the cracking load of test beams, improve ductility and reduce cracks width; the increasing of strength of precast shell concrete can improv the ultimate bearing capacity of test beams; the setting of keyway can improve the ultimate bearing capacity, slow the stiffness degradation, and imprve the ductility of the beam; the bearing capacity, crack width and deflection of semi-precast beams with keyways under bending load can be calculated according to Technical specification for fiber reinforced concrete(CECS 38∶2004).

Keywords:simi-precast;steel fiber; high-strength concrete;flexural performance;monotonic load test; keyway

*國(guó)家自然科學(xué)基金項(xiàng)目資助（51678009），北京市教委科技重點(diǎn)項(xiàng)目資助（KZ201710005003）。

作者簡(jiǎn)介：張建偉，博士，教授，博士生導(dǎo)師，Email: zhangjw@bjut.edu.cn。