负弯矩区钢-混凝土组合梁腹板开洞处钢筋受力性能研究  

Study on stress properties of steel-concrete composite beams withweb openings in negative bending moment zone

作　　者：陈静 廖文远 刘德稳 蒋伟 谢鑫 CHEN Jing;LIAO Wenyuan;LIU Dewen;JIANG Wei;XIE Xin(School of Civil Engineering,Southwest Forestry University,Kunming 655024,China)

机构地区：[1]西南林业大学土木工程学院,云南昆明655024

出　　处：《西安建筑科技大学学报（自然科学版）》2024年第1期14-22,共9页Journal of Xi'an University of Architecture & Technology(Natural Science Edition)

基　　金：国家自然科学基金青年基金项目(51808467);云南省教育厅科学研究基金项目(2022Y609)。

摘　　要：为了解负弯矩区腹板开洞钢-混凝土组合梁的内部受力钢筋的力学性能,对多个腹板开洞组合梁试件进行了试验研究和有限元分析,研究重点是洞口区域混凝土板内的钢筋受力特点和规律.试验及分析结果表明:负弯矩作用下,腹板开洞组合梁的破坏发生在洞口区,而不是弯矩最大处,洞口区混凝土板裂缝开展迅速并最终断裂,洞口处发生了明显的空腹破坏,洞口四角出现了次弯矩;在次弯矩作用下,洞口区混凝土板内的受力钢筋一部分受压,一部分受拉,钢筋的抗拉作用并没有充分发挥,其中洞口左端的上层钢筋受拉最为明显,抗拉作用较好;在合适的位置添加附加钢筋可以限制洞口上方混凝土板的裂缝开展,能够有效的提高试件的承载力和变形能力,其中在距离中心轴65 mm处添加直径为8 mm的附加钢筋时,试件的承载力和变形能力的提高效果最好.In order to understand the mechanical properties of the internal stressed reinforcement of the steel-concrete composite beam with openings in the web in the negative bending moment area,experimental research and finite element analysis were carried out on a number of composite beam specimens with openings in the web.The research focused on the stress characteristics and laws of the steel bars in the concrete slab in the opening area.The test and analysis results show that,under the action of negative bending moment,the failure of composite beams with web openings occurs in the opening area,not at the place with the maximum bending moment.The cracks in the concrete slab in the opening area develop rapidly and eventually break,with obvious hollow damage occurring at the opening and secondary bending moments appearing at the four corners of the opening.Under the action of the secondary bending moment,part of the stressed reinforcement in the concrete slab in the opening area are compressed and part are strained,and the tensile effect of the reinforcement is not fully exerted,among which the upper reinforcement at the left end of the opening is most obviously strained and the tensile effect is better.Adding additional steel bars in appropriate positions can limit the development of cracks in the concrete slab above the opening,and effectively improve the bearing capacity and deformation capacity of the specimen.Among them,the addition of additional steel bars with a diameter of 8 mm at 65 mm from the central axis has the best improvement effect on the bearing capacity and deformation capacity of the specimen.

关 键 词：组合梁 腹板开洞 负弯矩区 板内钢筋 附加钢筋 

分 类 号：TU3[建筑科学—结构工程]