摘要
为解决低强度混凝土基材上化学植筋承载力不足的技术难题,提出了一种采用小直径钢筋植筋+灌浆料锚固的新型混合连接构造.为验证所提连接构造的可行性,设计了4种锚固连接构造的对比试验,包括植筋胶全粘结、植筋胶部分粘结、灌浆料连接和新型混合连接.单筋拉拔实验结果显示,新型混合连接构造可有效提高低强度混凝土基材上的化学植筋承载能力,相对于植筋胶全粘结的连接构造,承载力提高近2倍,且不会出现混凝土椎体破坏.结果表明:对于在低强度混凝土基材上进行钢筋后锚固连接,若空间尺寸满足要求,可采用新型混凝土连接构造,确保节点连接性能满足要求.
Due to inadequate bearing capacity of the chemically-planted steel bar in low-strength concrete, a new mixed post-installed connection is proposed using small diameter anchoring steel bars and grouting materials together to anchor the main steel bar. To investigate the feasibility of the proposed post-installed connections, a series of pull-out tests with different anchors were conducted for comparison,including fully adhesive anchors, partially adhesive anchors,grouting material anchoring connection and the new mixed post-installed connection. The experimental results of the single steel bar pull-out test show that the mixed post-installed connection can effectively enhance the bearing capacity of post-installed steel bars in low-strength concrete. The bearing capacity is increased by nearly two times with no cone-type concrete failure compared with the fully adhesive anchor. The results show that adopting the new mixed post-installed connection can ensure that joint performance meets the requirements if the space dimension is available.
基金
The National Natural Science Foundation of China(No.51409084)
the Natural Science Foundation of Jiangsu Province(No.BK20130836)
关键词
低强度混凝土
新型连接构造
化学植筋
承载力
破坏形态
low-strength concrete
post-installed connection
chemically-planted steel bars
bearing capacity
failure pattern