钢-混凝土组合梁的收缩徐变效应分析

混凝土的自身收缩会在钢-混凝土组合梁中产生应力重分布,在收缩徐变的长期作用下混凝土梁可能会产生收缩裂缝。对于按无支撑法施工的钢-混凝土梁,采用弹性理论推导了混凝土梁的纵向拉应力和钢、混凝土之间的剪应力计算公式,并结合错位法分析了剪应力公式中的均剪弹性系数Ct,进而确定了剪应力值。算例分析结果表明,推导出的混凝土梁纵向拉应力和剪应力公式可以为混凝土梁的抗收缩和钢、混凝土之间的抗剪设计提供参考。

SHRINKAGE AND CREEP EFFECTS OF STEEL-CONCRETE COMPOSITE BEAMS

Shrinkage of concrete leads to stress redistribution in steel-concrete composite beams,and long-term shrinkage and creep effects of concrete may cause cracks on the concrete beams.For composite beams constructed by unsupported approach,formulas of vertical tensile stress on the cross section of concrete beams and shears on the contact surface between steel and concrete were derived by elastic theory,and shear elastic coefficient in the shear calculating formulas was also confirmed by lack of fit approach,so shears on the contact surface between steel and concrete can be calculated.Taking a composite beam for example, these formulas can provide references for shrinkage stress and shear resistance design of composite beams.