矩形钢管混凝土结构粘结性能研究

钢管混凝土结构因承载力高、抗震性能好、施工进度快,已在国内外许多重大工程中得到广泛应用。钢管混凝土结构通过钢管与混凝土间的传力实现两者的共同工作,尽管依靠固有粘结力被认为是最为经济理想的传力方式,但由于对粘结机理的认识尚不充分,规范制定得都较为保守。结合参与修订美国钢结构设计规程的经历,分析了粘结性能的研究现状,重点阐述了粘结承载力设计公式中有效粘结范围和名义粘结强度,通过对比推出、推离试件与实际钢管混凝土构件的受力状态,提出以节点试验代替上述试验定量钢管混凝土构件的粘结强度,并以此形成粘结承载力设计公式。

STUDY ON BOND BEHAVIOR OF RECTANGULAR CONCRETE FILLED STEEL TUBES

Due to its higher strength,better seismic behavior and faster construction,the structural system of concrete filled steel tubes has been widely used in some significant buildings around the world.The composite action of the steel tube and concrete fill is ensured through the load transfer from steel girders to concrete fill.Even natural bond is often the most economical connection detail;bond capacity is substantially underestimated in countries＇ codes due to the poor understanding on the bond mechanism.This paper introduces the evolution of the provisions on bond capacity in the Specification for Structural Steel Buildings compiled by American Institute of Steel Construction（AISC）.The equation is then elaborated in terms of nominal bond strength and effective bond area involved in bond capacity.Comparing the loading mechanism in the bond interfaces between actual connections and push-out and push-off specimens,connection tests are then proposed to derive the bond strength for modification of the design equation of bond capacity.