碳化腐蚀预应力空心板疲劳特性试验研究

Fatigue Characteristics of Prestressed Hollow Slab under Carbonation Corrosion

为了研究碳化侵蚀作用下耐久性损伤预应力空心板梁疲劳特性,基于相似性原理,依据实际桥梁结构中常用的20 m跨径预应力混凝土空心板梁结构参数,按照0.1的相似比设计并制作预应力混凝土空心板梁模型,在对其进行碳化侵蚀耐久性试验(轻、重两种侵蚀程度)的基础上,分别对其开展静载破坏试验、结构疲劳试验等.研究碳化腐蚀程度对结构动静力参数及疲劳寿命的影响,以及疲劳加载次数对试验构件动静应变、挠度、振动频率及阻尼的影响.建立碳化侵蚀程度与结构疲劳特性间的相关关系.试验结果表明,随着碳化腐蚀程度的增加,试验板疲劳寿命逐渐降低并发生疲劳脆性破坏,重度碳化试验板疲劳寿命急剧减少,同时结构动静力参数受疲劳加载次数的影响显著.

This aimed to examine study the fatigue properties of prestressed hollow slab beams under the action of carbonization,with the structural parameters of 20 m span prestressed concrete hollow slab beams which are commonly used in practical bridges engineering. The prestressed concrete hollow slab beam model（ ratio of similitude is 0. 1） was designed and manufactured based on the similarity principle. The carbonation erosion durability test（ two kind of erosion degree： light and heavy） was carried firstly,then the static load failure test and the structural fatigue test were performed to study the effect of carbonation corrosion on dynamic and static parameters and fatigue life,and the influence of fatigue loading on dynamic and static strain,deflection and fundamental frequency of the test members. Based the test results,the relationship between the degree of carbonation erosion and the structural fatigue properties were established. The results showed that with the increase of the degree of carbonization corrosion,the fatigue life of the test plate would be gradually reduced and the fatigue brittleness destroy world appear,especially for heavy carbonation test plate,the fatigue life would be drastically reduced. And with the increase of fatigue loading times,the dynamic and static parameters of the structure would gradually decrease.