对砼组成材料——骨料的视比重概念及其对砼配合比影响的探讨

Approach to the Concept of Specific Gravity of Aggregate—Concretemaking Material and Its Effect on Concrete Mix Proportion

用“绝对体积法”进行砼的配合比设计是国内外主要方法之一,而材料的视比重是计算的关键.由于重量取值及计算体积取值状态组合有三,所以视比重值有三个,这一点在我国规范及书籍中定义不清,影响砼配合比设计,而且取值不当,增加了水泥的用量.本文作者通过对骨料及砼拌和物的大量试验与分析,提出了对视比重概念的见解和砼配合比设计的合理状态,对明确计算及节省水泥有其意义.

Using the method of calculation by absolute volume to design co- ncrete mix proportion is a main metheod both at home and abroad,while the specific gravity of aggregate is the key to calculation.According to the three conditons of getting weight and volume,three types of specific gravity are defined.As the definitions of them are not clear in the Code and books in our country and the values of them are unc- orrectly calculated,the concrete mix proportion is affected and more cement is used in concrete.Basing on a large amount of experiment and analysis of aggregate and fresh concrete,the writers have pro- vided their suggestions to the concept of specific gravity and an ad- equate condition for concrete mix proportion design,which are sign- ificant to defining calculation and saving cement.