钢-混凝土组合箱梁剪力滞系数实用计算方法

Practical calculation method of shear lag coefficient of steel-concrete composite box beam

为了考察剪力滞后效应对钢-混凝土组合箱梁力学性能的影响,利用综合考虑剪力滞、剪切变形和界面滑移效应的钢-混凝土组合箱梁解析计算方法对混凝土顶板及钢梁底板剪力滞系数进行理论计算,主要考察宽跨比、剪力连接度和顶底板厚度3个主要影响因素对组合箱梁剪力滞系数的影响。计算结果表明:随着宽跨比的增大,顶板剪力滞系数及底板剪力滞系数均减小;在宽跨比较大时,顶板厚度对顶板剪力滞系数有较大影响,但对底板剪力滞系数的影响较小;顶板及底板剪力滞系数受剪力连接度的影响非常小,因此,在剪力滞系数计算中可以忽略剪力连接度的影响,采用完全剪力连接度进行计算。在大量计算数据基础上提出较为准确的混凝土顶板及钢梁底板剪力滞系数实用计算公式,计算形式简洁,便于工程应用。

Abstract： In order to study the influence of the shear lag on the steel-concrete composite box beam, a lot of shearlag coefficients of the concrete roof and steel baseboard were calculated using analytical calculating methodconsidering the shear lag effect, shear deformation, slip. The influence of width-span ratio, degree of shearconnection, roof thickness and bottom thickness which are main influence factors of shear lag coefficient wasmainly examined. The calculation shows that shear lag coefficient of the concrete roof and steel baseboarddecrease with the increase of the span ratio. When the width-span ratio is fairly great, the influence of roofthickness on shear lag coefficient of the concrete roof is great, but small on steel baseboard, which can be neglect.The influence of degree of shear connection on shear lag coefficient of the concrete roof and steel baseboard isfairly small. The influence of degree of shear connection on shear lag coefficient can be neglect and the full shearconnection can be used when calculating. In the end, the practical calculation shear lag coefficient experiencecomputational formulas were put forward based on a large number of calculation data, which was convenient tobe used in engineering.