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要想混凝土得到良好的固化,一定要防止新浇筑的混凝土表面水份过多蒸发。该问题处理不好,会导致水泥的水合作用程度降低,使混凝土迭不到令人满意的质量。有许多养护方法可以采用,以确保水泥在水合作用发生过程中保持足够的水份。然而对混凝土的养护总难达到满意的效果。本文所要探讨的就是如何使混凝土得到最适度的养护而不必运用外部保养的方法。此文讨论了混凝土拌合时加入水溶性化学物,使凝结的混凝土减少水份蒸发达到“自身养护”的可行性。这些化学物对减少溶液的蒸发和加强普通硅酸盐水泥的水保持所产生的效能可通过检测失重来进行测定。X射线药粉衍射和温差重量测定法的检测手段被用来评估水保持的增加是否与水泥水合作用程度的提高达到一致。早期表面吸收实验和抗压强度检测可分别测定混凝土表面渗透性和固化。化学掺合物对水泥浆微结构产生的影响则通过电子显微镜扫描来测试。在所研究过的化学物中有两种被发现具有明显的“自身养护”效能。其中一种对水合作用的提高还远远超过了水保持的增强。下面是对这种性能所给予的说明。
To get a good solidification of the concrete, it is necessary to prevent excessive evaporation of water on the surface of the newly cast concrete. The poor handling of this problem will lead to a decrease in the degree of hydration of the cement and a lack of satisfactory quality of the concrete. There are many conservation methods that can be used to ensure that cement maintains sufficient moisture during hydration. However, the maintenance of concrete is always difficult to achieve satisfactory results. What this article wants to discuss is how to get the concrete to the optimum degree without using external maintenance. This article discusses the feasibility of adding water-soluble chemicals during concrete mixing to reduce the evaporation of condensed concrete to “self-conservation”. The effectiveness of these chemicals to reduce the evaporation of the solution and to enhance the water retention of ordinary portland cement can be measured by detecting the weight loss. X-ray powder diffraction and thermogravimetric measurements were used to assess whether the increase in water retention was consistent with the increase in cement hydration. Early surface absorption experiments and compressive strength tests can measure concrete surface permeability and cure, respectively. The effect of chemical blends on the microstructure of the cement slurry was tested by scanning electron microscopy. Two of the studied chemicals were found to have significant “self-conservation” efficacy. One of these improvements in hydration far exceeds the enhancement of water conservation. The following is a description of this performance.