It is the purpose of this paper to develop the new type mixed cement with fluidity and adhesive property. PC (ordinary Portland cement) or MC was used as main raw materials. MC stands for the mixed cement which consists of a 3 : 2 mixture of PC and JC (special super high early strength cement). As admixtures, sodium caseinate and calcined alunite were added to them before mixing water in order to let have new properties. The results were summarized as follows.
1) Sodium caseinate retards the set of PC, JC or MC.
2) PC (or MC) containing sodium caseinate is more fluid than without it.
3) Mortar surfaces can be thoroughly bonded together with PC (or MC) paste containing sodium caseinate.
4) Calcined alunite has an accelerating action on the set of PC.
5) There is no effect of the sole calcined alunite on setting of JC. But the effect of sodium caseinate as a retarder of JC becomes even stronger when calcined alunite coexists with them.
6) The shrinkage percentage of PC is decreased by mixing of JC.
7) JC acts an accelerator of set for PC.
8) Sodium caseinate decreases the compressive strength of PC (or MC) but the addition of calcined alunite reduces the strength at early ages.
9) It is possible to control some properties such as the fluidity, the adhesive strength, the setting time and the compressive strength by combining PC, JC, sodium caseinate and calcined alunite.
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