现浇混凝土板早期顺筋裂缝研究  

Research on Early Cracks Along Steel in Cast-in-place Concrete Slabs

作　　者：屈文俊[1] 秦怡惟 朱鹏[1] 侯克亮 

机构地区：[1]同济大学建筑工程系,上海200092

出　　处：《结构工程师》2015年第5期159-165,共7页Structural Engineers

基　　金：国家自然科学基金青年科学基金项目(51208373);中央高校基本科研业务费专项资金资助(2011KJ044)

摘　　要：在施工早期出现顺筋裂缝的工程实例并不少见。为分析早期混凝土板中产生顺筋裂缝的原因,利用早期混凝土抗拉强度、弹性模量等方面的研究,对早期弹性模量曲线进行类比,并计算温度应力。设计制作了26块抗折试件,分别养护11 h、16.5 h、20 h和24 h后进行抗折试验,试验验证了早期混凝土的抗拉强度与混凝土与钢筋之间的垂直抗拉强度的区别。混凝土与钢筋之间较低的垂直抗拉强度是顺筋裂缝产生的主要原因。It is not rare discovering cracks along steel during early construction. In order to find out the reasons of such cracks in cast-in-place concrete slabs,analysis of the properties including tensile strength and elastic modulus of concrete at early ages was did. The curves of elastic modulus in relevant academic articles were used to analyze the reason of cracks and calculate the temperature stress. Twenty six specimens were put in the test of bending strength when their ages arrive respectively at 11 h,16. 5,20 h,24h. The results showed the difference between tensile strength of concrete and vertical tensile strength of the interface between steel and concrete,which is the main reason for cracks along steel in the cast-in-situ concrete floor slab.

关 键 词：早期混凝土性能 顺筋裂缝 温度应力 钢筋和混凝土接触面早期强度 

分 类 号：TU755.7[建筑科学—建筑技术科学]