内部相对湿度对含氧化镁混凝土收缩变形的影响

Influence of internal relative humidity on shrinkage and deformation of concrete containing magnesia

为了研究内部相对湿度、氧化镁和监测位置对混凝土材料收缩变形和内部相对湿度的影响,开展了不同条件下混凝土内部相对湿度和收缩变形的试验。结果表明:随着外界环境相对湿度的不断增大,在同一距离预留干燥面条件下,混凝土内部相对湿度的变化规律呈现出不断增大的趋势,混凝土干燥收缩率的变化规律呈现出不断减小的趋势。在同一监测位置处,掺加氧化镁混凝土的相对湿度要大于不掺加氧化镁混凝土的相对湿度,掺加氧化镁混凝土的干燥收缩率要小于不掺加氧化镁混凝土的干燥收缩率;掺加氧化镁的混凝土可以有效地降低混凝土的干燥收缩率,且有效降低了混凝土内部相对湿度。

In order to study the influence of internal relative humidity,magnesium oxide and monitoring location on the shrinkage deformation and internal relative humidity of concrete materials,experiments on the internal relative humidity and shrinkage deformation of concrete under different conditions were carried out.The results show that with the continuous increase of the relative humidity of the external environment,under the condition of the same distance reserved for drying surface,the change law of the relative humidity inside the concrete shows a continuous increase trend.The change law of concrete drying shrinkage has shown a decreasing trend.At the same monitoring location,the relative humidity of concrete mixed with magnesium oxide is greater than that of concrete without magnesium oxide.The shrinkage deformation of concrete with magnesium oxide is smaller than that of concrete without magnesium oxide.Concrete mixed with magnesium oxide can effectively reduce the drying shrinkage of concrete.And it effectively reduces the relative humidity inside the concrete.