【摘要】 新浇筑的早龄期混凝土结构受到地震作用后钢筋与混凝土间产生相对变形,尤其是预留钢筋随地震作用的甩动,会导致钢筋与混凝土间粘结特性改变。通过终凝初期(12h)混凝土与钢筋受地震作用(峰值加速度分别为0.45g,0.25g,0.15g,0.06g,0.00g)的模拟试验,探讨了钢筋甩动使混凝土表面产生空穴的机理和形态、受振动后钢筋沿锚固长度的应变分布与粘结应力变化关系、早龄期混凝土在受振后粘结应力损失的规律等。研究结果表明:空穴的大小与振动力大小相关,且会影响钢筋与混凝土的粘结应力分布形态,使有效锚固长度减小。更多还原

【Abstract】 The relative deformation between reinforced bars and concrete would be present in the early-age concrete under the earthquake action,especially with the reinforced bars swinging,the change of bond behavior between reinforced bars and concrete would happen.Simulative experiments of the early-age reinforced concrete(12h) under different degrees of seismic actions(0.45g,0.25g,0.15g,0.06g and 0.00g) were carried out.The mechanism and formation of the gaps in early-age concrete associated with swinging actions of reinforced bars,the stress-strain relationship along the anchorage length,and the loss of bond stress after vibration were investigated.The results show that the scale of gap relates to the seismic forces,changes the distribution of bond stresses,and reduces the effective anchorage length.更多还原