轴压钢管混凝土格构柱剪力计算

Calculation of Shear Force in Concrete Filled Steel Tubular Columns Under Axial Compression

钢管混凝土格构柱中的缀件主要用于承担剪力,剪力的计算是设计格构柱缀件的关键.现行钢管混凝土结构设计与施工规程(CECS 28:90)对于格构柱剪力的计算基本上是参照钢结构设计规范的相应规定,未能很好地反映钢管混凝土格构柱中剪力的变化规律.而本文在考虑钢管混凝土紧箍效应及格构柱剪切变形基础上,推导了钢管混凝土格构柱的剪力计算公式.该公式形式简洁,考虑了长细比、钢管屈服强度和核心混凝土强度对剪力的影响,适用于轴压四肢钢管混凝土格构柱剪力计算.公式计算结果与有限元计算结果吻合良好,验证了公式的正确性.

Laing and batten elements play a vital role in contributing towards the shear force in concrete filled steel tubular（CFST） laced columns.So it is very important to calculate the force in these members for designing.The formula used for its calculation in Specification for Design and Construction of Concrete-Filled Steel Tubular Structures（CECS 28：90） is based mostly on the same lines as in Code for Design of Steel Structures,but it doesn’t differentiate between them.Based on the confinement effect and the shear deformation of the laced columns,a new formula is derived to calculate the shear force.The influence of slenderness ratio,yield strength of tubes,and strength of concrete are considered in the formula.The formula is concise and it can be used to calculate the shear force in CFST laced columns with four legs.At the same time,the formula is found to have good agreement with results of test.So the rationality of the formula has been attested.