（1 同济大学土木工程学院， 上海 200092； 2 上海杉达学院， 上海 201209）

［摘要］部分包覆钢-混凝土组合构件因两种组成材料的相互约束，能大幅增强H型钢翼缘的局部稳定性，因而设计时可以采用较大宽厚比的板件。增大冀缘宽厚比能提高钢材利用效率，但也存在降低构件承载能力和塑性变形能力的风险。对这类构件中钢翼缘板受压条件下的局部稳定性能进行了研究，推导了弹性与弹塑性失稳条件下的临界应力与冀缘宽厚比；根据试验研究结果，分析了翼缘宽厚比和连杆间距对构件延性的影响；讨论了现行规范有关规定的合理性。结果表明：混凝土单侧约束能大幅提高钢板的局部稳定临界应力，并可由此推导出PEC构件中主钢件翼缘板的宽厚比限值；当设置连杆约束时，在一定范围内采用较密的连杆间距，可以满足较大宽厚比截面的塑性承载的要求。

［关键词］部分包覆钢-混凝土组合构件；翼缘宽厚比；临界应力；连杆间距；局部稳定性；延性

中图分类号：TU398+.9文献标识码：A文章编号：1002-848X(2021)07-0001-06

Research on local stability performance of main steel flange in partially-encased composite steel and concrete members

CHEN Yiyi1,2, LIN Junxing1, LI Jie1

(1 College of Civil Engineering, Tongji University, Shanghai 200092, China; 2 Sanda University, Shanghai 201209, China)

Abstract:The local stability of H-shaped steel flange in partially-encased composite steel and concrete (PEC) members  may be enhanced because of their mutual restraint of steel and concrete materials, therefore, the plate with relative large width-thickness ratio can be adopted in design. Increasing the flange width-thickness ratio can improve the efficiency of steel utilization, but there is also the risk of reducing the load-bearing capacity and plastic deformability of members. The local stability performance of mian steel flange under compression in PEC members was studied, and the critical stress and width-thickness ratio under elastic and elastoplastic instability conditions were derived; referring to test results, the effects of steel flange width-thickness ratio and the interval of links on the ductility of members were analyzed; the rationality of the current specification about the local stability was discussed. The results show that concrete unilateral restraint can greatly increase the local stability critical stress of steel plate, and the flange width-thickness ratio limit of the main steel flange plate in the PEC member can be derived, when setting the link constraint, a small interval is used within a certain range, which can meet the requirements of plastic load-bearing of the section with a larger width-to-thickness ratio.

Keywords:partially-encased composite steel and concrete member;flange width-thickness ratio;critical stress;interval of link;local stability;ductility

作者简介：陈以一，博士，教授，博士生导师，Email:yiyichen@tongji.edu.cn;通信作者：林俊星，硕士研究生，Email:1659320139@qq.com。