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用测定膨胀与强度、ｐＨ值及ＳＥＭ方法，研究了钾、钠对自应力硫铝酸盐水泥及其混凝土的影响。结果表明，碱对于Ｃ２Ｓ水化、钙矾石快速形成具有促进作用，使矾石结晶细小、水泥石结构致密、脱模强度增高，在不能承受水泥继续水化新形成钙矾石导入的大膨胀压时即造成结构破坏。水泥及其混凝土的膨胀值越大，这种破坏程度越重；碱含量越高，这种破坏发生的时间越早；本文将这种破坏称之为碱害。碱害造成的试体形变多发生在水养阶段的第３～７ｄ，可将其视为前期爆管的一种征兆。
The effects of potassium and sodium on the self-stressing sulphoaluminate cement and its concrete were investigated by measuring swelling and strength, pH value and SEM method. The results show that alkali can promote the formation of C2S hydration and ettringite formation, and the fineness of vermiculite crystals, the compactness of cement stone structure, and the strength of demolding are increased, and the large expansion of ettringite introduced by the unrelenting continuous hydration of cement can be tolerated. When it is pressed, it will cause structural damage. The greater the expansion value of cement and its concrete, the more severe this damage is; the higher the alkali content, the earlier this damage occurs; this damage is called alkali damage in this paper. The deformation caused by alkali damage occurred mostly in the 3rd to 7th of the water culture stage, which can be considered as a sign of early explosion.