摘要
为研究钢筋-金属波纹管灌浆连接的锚固性能,设计并制作了23组灌浆连接试件.基于拉拔试验,分析了钢筋锚固长度la、孔径比D/d和螺旋箍筋约束等因素对灌浆连接锚固性能的影响.研究结果表明,试件的破坏形式包括钢筋拉断、钢筋拔出、金属波纹管拔出和混凝土开裂等4种,且以钢筋拉断为主.当孔径比D/d=1.90~2.23时,试件由于试验原因多未发生破坏,但钢筋均达到屈服强度.当孔径比D/d=2.52~3.50且锚固长度la≥10d时,试件破坏形式均表现为钢筋拉断.当孔径比D/d=1.90~3.50且锚固长度la=7d^24d时,钢筋的黏结刚度随锚固长度la和孔径比D/d的增大呈先增大后减小的趋势.在外径为89 mm的金属波纹管内加入螺旋箍筋后,钢筋黏结滑移量显著降低,锚固性能明显提升.在工程应用中,当钢筋直径不大于25 mm时,建议锚固长度la取10d^15d,孔径比D/d取2.50~3.50.
To study the anchorage performance of rebar-corrugated metal duct for grout splicing, 23 groups of grout splicing specimens were designed and produced. The effects of the factors such as the anchorage length la, the diameter ratio D/d and steel spiral confinement on the anchorage performance of rebar-corrugated metal duct for grout splicing were analyzed by pull-out tests. The results show that the failure modes of the specimens include rebar fracture, rebar pull-out, corrugated metal duct pull-out and concrete splitting, and the rebar fracture is the main failure mode. When D/d=1.90 to 2.30, most of the specimens don’t fail due to the test reasons, but the rebar can all reach yield strength. When D/d=2.52 to 3.50 and la≥10 d, the failure mode of specimens is all rebar fracture. When D/d=1.90 to 3.50 and la=7 to 24 d, with the increase of the anchorage length and the diameter ratio, the bond stiffness of the rebar increases first and then decreases. The slipment of the rebar can be effectively reduced by steel spiral inserted in corrugated metal duct with the outer diameter of 89 mm to improve the anchorage performance of the rebar. When the rebar diameter is no more than 25 mm, the anchorage length la is recommended to be 10d to 15d and the diameter ratio to be 2.50 to 3.50.
作者
王浩
柳家为
石棚
陶天友
祝青鑫
Wang Hao;Liu Jiawei;Shi Peng;Tao Tianyou;Zhu Qingxin(Key Laboratory of Concrete and Prestressed Concrete Structures of Ministry of Education,Southeast University,Nanjing 210096,China)
出处
《东南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2020年第2期215-221,共7页
Journal of Southeast University：Natural Science Edition
基金
国家自然科学基金资助项目(51578151)
国家“万人计划”青年拔尖人才资助项目(W03070080)
江苏省重点研发计划资助项目(BE2018120).
关键词
金属波纹管
灌浆连接
锚固性能
锚固长度
孔径比
螺旋箍筋约束
corrugated metal duct
grout splicing
anchorage performance
anchorage length
diameter ratio
steel spiral confinement
