【摘要】 本文研究了外加剂、砂率、掺合料对轻集料混凝土新拌混合料坍落度经时损失的影响。结果表明 ,外加剂影响最大 ,其次是砂率、掺合料。适当提高砂率 ,混凝土用水量基本不变 ,但能防止新拌混合料离析泌水 ;采用粉煤灰等量取代水泥 ,不但能降低新拌混合料坍落度经时损失 ,还能改善新拌混合料的和易性 ;通过掺加复合外加剂研制出大坍落度 ,1h坍落度经时损失小 ,不离析泌水 ,硬化后表观密度小 ,抗压强度高 ,抗冻性、抗碳化性良好的高性能轻集料混凝土。更多还原

【Abstract】 ? The contributory factors of the mixture slump loss with time were studied.The factors include concrete admixture,sand ratio and mineral admixture.The result indicated that the effecting order is concrete admixture,sand ratio and mineral admixture in turn.Adding properly sand ratio can prevent gravity segregation and weeping of concrete mixture and keep the water content constant.Fly ash replacing equally cement can reduce the slump loos and increase the mixture workability.By using compound admixture,high performance light aggregate concrete with high slump was made up.It has some merits,such as low slump loss,no gravity segregation,non weeping,lower dry density,higher compressive strength,good frost thaw resistance,and so on. 〔更多还原