砂率对自应力混凝土坍落度的影响

Influence of sand ratio on the slump of self-stressing concrete

自应力混凝土(SSC)因要获得工程所需的自应力水平,自应力水泥用量较大,拌合物的工作性能受较大影响,故其配合比设计与普通混凝土有较大差别。从砂率对新拌自应力混凝土坍落度的影响入手,利用直角坐标系和半对数坐标系下砂率-坍落度关系,分析得到自应力混凝土最佳砂率取值范围。同时根据试验数据对经典的Fuller砂石理想级配关系式进行修正,以适应自应力混凝土配合比设计需要。进而提出利用改进Fuller公式下的整体细度模数以及粗、细集料细度模数求得最佳砂率范围的方法,为自应力混凝土的工程应用提供设计参考。

As self-stressing concrete （ SSC ） is supposed to get self-stressing level need by the construction, a large quantity of expansive cements are hence demanded,which makes a great difference to the working performance of the mixture and the mix design of SSC from the common concrete.Based on the relationship between sand ratio and slump, the effect of sand ratio on slump of fresh self-stressing con- crete was investigated.Meanwhile, according to the result of slump tests, Fuller formula was rectified to satisfy the mix design of SSC. Then, a new approach to find the optimized sand ratio of SSC was proposed as a reference for construction design.