重复荷载下混凝土中钢筋锚固长度的理论分析  

Theoretical analysis on anchorage length of bars in concrete under repeated loading

作　　者：蒋德稳[1] 邱洪兴[2] 

机构地区：[1]淮海工学院土木工程学院,江苏连云港222005 [2]东南大学土木工程学院,江苏南京210096

出　　处：《四川建筑科学研究》2013年第6期36-40,共5页Sichuan Building Science

基　　金：973项目(2007CB714200)

摘　　要：为了研究重复荷载下混凝土中钢筋的临界锚固长度,首先运用粘结滑移基本微分方程,基于Balazs静载下局部粘结滑移本构关系推导了临界锚固长度理论解,分析了混凝土强度、保护层厚度和钢筋直径对静载下锚固长度的影响;然后基于Byung Hwan重复荷载下局部粘结滑移本构关系,根据粘结疲劳寿命基本理论,即当重复荷载下钢筋滑移量增长到静载最大滑移量时发生粘结疲劳破坏,推导了重复荷载下粘结锚固长度公式,分析了应力水平、应力循环次数对重复荷载下锚固长度的影响。研究表明:重复荷载下,由于粘结性能的退化,钢筋的临界锚固长度应有所增加,在低应力水平下,重复荷载次数对锚固长度影响不大,在高应力水平下影响明显。研究结果可为深入研究混凝土结构疲劳性能提供依据和方便。In order to study the rebar＇s critical length under repeated loading, according to the basic differential equation of the relationship between bond stress and slip, the theoretical solution of the critical anchorage length was deduced based on Balazs＇s bond- slip basic constitutive relation models under monotonic loading. The effect of concrete strength, thickness of concrete cover and rebar diameter on anchorage len^h were analyzed. Based on Byung Hwan＇s bond-slip basic constitutive relation models under repeated loading, the critical length of repeated loading was inferred according to Balazs＇s bond fatigue life theory （ i. e. , the condition of bond fatigue damage is that slippage under repeated loading reach the maximum slippage under monotonic loading）. The effect of stress levels, repeated times on anchorage length were also analyzed. Research shows that the critical anchorage length under repeated loading should be increased because of bond performance deterioration. Under low stress level, the repeated times have little influence on the anchorage length, while the influence under high stress level is distinct. The results of the present study are expected to be useful for thorough analysis of concrete structure＇s fatigue performance.

关 键 词：锚固长度 粘结 滑移 钢筋混凝土 

分 类 号：TU375.4[建筑科学—结构工程]