【摘要】 本文通过162块新老混凝土粘结Z形剪切试件的试验,研究了冻融循环对新老混凝土粘结面剪切性能的影响。试件在温度-18℃～8℃范围内经受了0、5、10、15、20和30次的冻融循环。分析了新老混凝土粘结面冻融损伤破坏的机理和冻融循环次数、界面处理方法、界面剂的类型以及新老混凝土的强度等对粘结面粘结剪切强度的影响。研究表明,在冻融循环作用下,新老混凝土粘结剪切强度随冻融循环次数的增加急剧下降,冻融30次时,所试验的试件几乎全部从粘结面冻融破坏。粘结剪切强度的下降是由于新老混凝土本身强度的下降和粘结剂强度的下降以及粘结面的损伤等共同作用的结果。更多还原

【Abstract】 The influence of cyclic freeze-thaw on shear strength of bonding interface between fresh and old concrete is studied experimentally. The specimens experience different freeze-thaw cycles with temperature variation from -18℃ to 8℃. It is found that the bonding shear strength decreases rapidly with the increase of freeze-thaw cycles. Failure takes place after 30 cycles. The bonding strength reduction is closely dependent on the strength of the concretes themselves and the characteristics of bonding interface including the adhesive agents adopted and procedure of surface cleaning.更多还原