流态混凝土梁板构件裂缝成因及控制

Causes of formation and controls of cracks in beams and slabs of fluid concrete

流态混凝土 ,特别是在高强度、大流动性条件下 ,具有水泥用量多 ,用水量大 ,砂率高 3个主要特点 ,所以产生裂缝的潜在危险大 ,在工程实践中梁板构件出现裂缝的情况比较多 ,对此必须引起足够的重视 总结了流态混凝土梁板构件非结构性裂缝产生的规律 ,将裂缝分成混凝土塑性收缩裂缝、干燥收缩裂缝、骨料塑性沉落裂缝、温度应力裂缝几类 ,系统地分析了以上几类裂缝的形成原因以及相关因素 提出从优化混凝土设计、提高混凝土生产质量、加强混凝土施工管理

The fluid concrete especially with high performance and high fluidity has the character of more cement and water consumption and high rate of sand. It is more common for cracks to appear in beams and slabs because of the characteristic of the fluid concrete. The rules for concrete cracks to occur have been summarized, with concrete cracks classified into plastic shrinkage cracks, dryness shrinkage ones, aggregate's plastic settlement ones and temperature stress ones. The causes and correlative factors of all these cracks have been analyzed. Effective measures to control the cracks have been put forward, such as improving concrete quality and strengthening construction management and the concrete design.