摘要
为研究火灾后预制空心板采用钢筋网细石混凝土加固前后的力学性能和破坏形态,对不同受火时间条件下采用钢筋网细石混凝土加固预制空心板的8个试件进行静力试验,其中3个对比未受火未加固试件,1个未受火加固试件,4个分别受火15、30、45和60 min后的加固试件。研究结果表明,钢筋网细石混凝土加固受火预制空心板均发生弯曲破坏;加固能有效抑制试件的开裂,提高弯曲刚度。加固试件的开裂荷载和极限荷载均大幅提高,极限位移有所降低。相同荷载作用下,钢筋网中受压纵筋压应变和孔洞内埋设受拉纵筋拉应变均随受火时间增加而增大。在考虑材料火灾损伤基础上,采用等效截面法计算加固试件的极限承载力是可行的。
To study the mechanical properties of fire-damaged prestressed concrete hollow-core slabs before and after strengthened with steel-meshed fine aggregate concrete, 8 specimens were experimentally studied by static load tests, which included 3 reference unex- posed specimens without strengthening, 1 unexposed specimen with strengthening, 4 fire-damaged specimens strengthened with steel- meshed fine aggregate concrete and exposed 15,30,45 and 60 rain, respectively. The test results showed that all the fire-damaged slabs strengthened with steel-meshed fine aggregate concrete collapsed with a bending failure mode, and their bending stiffnesses were in- creased. The crack strength and the ultimate flexural strength of the strengthened slabs were all obviously increased, and the ultimate deformation was decreased slightly. The predictions of ulitmate flexural strength of strengthened slabs were in close agreement with the test results after taking the fire damage of material into consideration.
出处
《四川大学学报（工程科学版）》
EI
CAS
CSCD
北大核心
2012年第6期61-66,共6页
Journal of Sichuan University (Engineering Science Edition)
基金
上海市科委应用技术开发项目(2011-114)
上海市人才发展资金资助项目(2011058)
华南理工大学亚热带建筑科学国家重点实验室开放课题(2010KB12)
关键词
预应力混凝土空心板
受火
钢筋网细石混凝土
加固
力学性能
PC hollow-core slab
exposed to fire
steel-meshed fine aggregate concrete
strengthening
mechanical behavior
