(1 重庆交通大学土木工程学院, 重庆 400074; 2 中国建筑科学研究院有限公司, 北京 100013;3 金科新能源有限公司, 北京 100102)

摘要: 为研究风电塔筒装配式基础采用的钢筋环形搭接后浇段连接节点的受弯性能,进行了 3 个采用后浇段连接的预制混凝土试件和 1 个现浇混凝土试件的受弯试验,分析了采用不同后浇段宽度及插销钢筋直径的预制试件的破环模式、承载力、变形能力及裂缝,并与现浇试件进行了对比。 结果表明:采用后浇段连接的预制试件的裂缝最先出现在结合面处,且开裂荷载显著小于现浇试件相应值,最大裂缝宽度发生于结合面处且显著大于现浇试件相应值;极限承载力达到现浇试件相应值的 86% ~ 96%,且试验值与规范计算值之比均大于 1. 2,后浇段连接能够有效传力且可采用规范公式计算其受弯承载力;搭接长度为 0. 35la( la 为锚固长度) 时,增大插销钢筋直径有助于搭接传力,能更充分地发挥连接节点的承载能力及变形能力;基于连接节点受力机理提出了最大裂缝宽度实用计算方法,计算结果与试验结果总体吻合良好且略偏于安全。

关键词: 钢筋环形搭接; 后浇段; 受弯性能; 裂缝宽度; 试验研究

中图分类号:TU375 文献标志码:A 文章编号:1002-848X(2022)13-0120-08

DOI:10. 19701 / j. jzjg. 20200967

Experimental study on flexural behavior of post-cast segment joint with loop lapped reinforcements

HU Chen1, ZHOU Jian2, TIAN Chunyu2, ZHANG Heming3

(1 College of Civil Engineering, Chongqing Jiaotong University, Chongqing 400074, China; 2 China Academy of Building Research Co. , Ltd. , Beijing 100013, China; 3 Jinke New Energy Co. , Ltd. , Beijing 100102, China)

Abstract:In order to study the flexural behavior of post-cast segment joint with loop lapped reinforcements used in wind turbine tower’ s precast foundation, the flexural tests of three precast concrete specimens with post-cast segment joint and one cast-in-situ concrete specimen were carried out. The failure mode, load-bearing capacity, deformation capacity and cracks of the precast specimen with different width of post-cast segment and diameter of bolt reinforcement were analyzed, and compared with the cast-in-situ specimen. The results show that the cracks of the precast specimen with post-cast segment appear at the joint interface firstly, and the cracking load is significantly less than the corresponding value of the cast-in-situ specimen. The maximum crack of the precast specimen occurs at the joint interface and is significantly greater than the corresponding value of the cast-in-situ specimen. The ultimate load-bearing capacity of the precast specimen can reach 86% ~ 96% of the cast-in-situ specimen’ s value, and the ratio of the experimental value to the code calculated value is greater than 1. 2. The post-cast segment joint can transfer force effectively and the flexural bearing capacity can be calculated by the code’ s formula. When the lap splice length is 0. 35 la ( la is the anchorage length) , increasing the diameter of bolt reinforcement is helpful to force transmission, which can give better play to the load-bearing capacity anddeformation capacity of the joint. Based on the joint mechanical mechanism, a practical calculation method of maximum crack width is proposed, the calculated results are in good agreement with the experimental results and are slightly safer.

Keywords:loop lap splice of reinforcement; post-cast segment; flexural behavior; crack width; experimental study

∗宁波市电力设计院有限公司科技项目(装配式 UHPC 高性能变电站技术体系研发) (KJCX003) 。

第一作者:胡晨,硕士,主要从事结构设计与研究,Email:825845722@ qq. com。

通信作者:周剑,硕士,工程师,主要从事新型建筑工业化结构技术研究,Email:zhoujian@ cabrtech. com。

[引用本文] 胡晨,周剑,田春雨,等. 钢筋环形搭接后浇段连接节点受弯性能试验研究[ J] . 建筑结构,2022,52(13) :120-127. HU Chen,ZHOU Jian,TIAN Chunyu,et al. Experimental study on flexural behavior of post-cast segmentjoint with loop lapped reinforcements[ J] . Building Structure,2022,52(13) :120-127.