Research on Standardized Method of Stress Release Method for Measuring the Stress of Concrete
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摘要: 预应力值检测是预应力混凝土结构检测的重要内容,但是,至今尚无标准化检测方法;超长混凝土结构温度收缩应力常引起大量混凝土结构裂缝超过相关规范要求,但是,对混凝土结构温度收缩应力的现场检测始终没有有效的方法。对不同截面形式、不同受力状态的4种情况进行了混凝土保护层开双槽应力释放的有限元模拟,在分析了应变释放率-槽深关系的基础上,提出了保护层25 mm开槽法和最大释放率法。发现,保护层25 mm开槽法的开槽速度快,可以消除温度的影响;最大释放率法数据稳定,推测值更为准确。最后通过某工程的现场测试验证了所提方法的可操作性和准确性。Abstract: Prestress detection is an important content of prestressed concrete structure detection, but there is no standardized method. The temperature shrinkage stress of super-long concrete structures after causes a large number of cracks which exceed the requirements of relevant specifications, but there is no effective method to detect the temperature shrinkage stress of concrete structures in situ. The finite element simulation of double groove stress release of concrete cover was carried out under four conditions of different sections and different stress states. Based on the analysis of the relations between strain release rate and groove depth, the 25 mm grooving method and the maximum release rate method of concrete cover were proposed. For concrete cover 25mm grooving method, the influence of temperature could be eliminated because of the grooving speed was fast. The data of maximum release rate method was stable and the predicted value was more accurate. The maneuverability and accuracy of the method were verified by field test of a certain project.
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Key words:
- stress release method /
- prestress /
- temperature shrinkage stress /
- stress detection
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