用更严密的方法确定沥青砼试件的体积指标

Setting the Volume Index of Asphalt Concrete Specimens with More Meticulous Method

详细讨论了影响沥青混凝土体积指标准确性的两大要素:准确测定试件的毛体积和沥青混凝土的理论最大密度。建议了合适的毛体积测定的两次蜡封法和钻件蜡封法。推荐用计算法确定理论最大密度,建议除<0 075mm的粉料可只用视密度外,其余矿料都应测定其毛体积密度和视密度,在计算集料的有效密度时,根据集料吸水率确定视密度和毛体积密度各自需用的比例。

This paper elaborates two key factors influencing the accuracy of the volume index of asphalt concrete, i.e. accurately measuring the bulk volume of specimens and the theoretical maximum density of asphalt concrete. It is suggested twice wax-coating method and method of drilling specimen coated with wax, which are available to the measurement of bulk volume. It is recommended that theoretical maximum density should be decided with calculation method and allmineral materials should be measured for their bulk volume density and apparent density, but powder materials <0.075mm as an exception, which need the measurement of apparent density only. When calculating the effective density of aggregates, the respective percentage of apparent density and bulk volume density should be decided according to specific absorption of aggregates.