单轴贯入试验试件高度对沥青混合料剪切强度的影响

将AC-13,AC-16和AC-20等3种沥青混合料制备成不同厚度的车辙板芯样试件,采用28.5 mm压头进行了单轴贯入试验,研究了不同试件高度对沥青混合料的抗剪强度性能的影响。结果表明:当3种沥青混合料试件高度分别等于或大于5 cm,6 cm和7 cm时,抗剪强度和剪切应变趋于常数,不再受试件高度变化的影响。结论是所研究的3种级配沥青混合料,将单轴贯入试验的试件厚度采用车辙试验确定出的与最大公称粒径相匹配的结构层厚度是合理的。

Influence of Specimen Thickness on Shear Performance of Asphalt Mixture in Uniaxial Penetration Test

Different thickness core samples drilled from the wheel tracking plate for AC-13,AC-16 and AC-20 asphalt mixtures were experimented by using Uniaxial Penetration Test Methods in which diameter 28.5mm head was used in order to study the effect of the different height core samples on shear strength properties of asphalt mixtures.The results showed that when the specimen height for AC-13,AC-16 and AC-20 were equal to or greater than 5cm,6cm and 7cm,the shear stress and shear strain were closed to a constant,and no longer subjected to the change of the specimens height.Therefore,the thickness of specimen,which matched the structure layer thickness with nominal maximum aggregate size obtained by wheel tracking test,was reasonable to be adopted in uniaxial penetration test.