一种基于电学特性的沥青混凝土吸水状况推测方法

沥青路面在使用过程中不可避免会受到自然降水和地下水的影响,水分交替作用最终将导致沥青路面的水损害,而以往室内测定沥青混凝土含水率的方法无法对沥青路面的干湿状态进行快速评定。为了快速评定沥青路面的干湿状态,采用电学方法推测沥青混凝土的含水率。以密实型沥青混凝土电阻特性为依据,测量浸水前后沥青混凝土电阻率的变化,进而建立沥青混凝土吸水率与其电阻率的数学关系,以电阻率来推测沥青混凝土内部的含水率。结果表明,沥青混凝土含水率与电阻率对数值具有良好的线性相关性,沥青混凝土吸水率越大,电阻越小。所提方法可为不同沥青混凝土面层的干湿状况评定提供一定的借鉴。

An estimation method for the absorbed moisture of asphalt concrete based on electrical resistance

Asphalt pavement is inevitably affected by the natural precipitation and groundwater in the service stage. Hydrologic cycle will eventually lead to the moisture damage of asphalt pavement. However, the existing indoor method for moisture measurement of asphalt concrete cannot quickly assess the pavement wetting state. Therefore, in order to evaluate the wet and dry state of asphalt pavement quickly, an electrical method is proposed to estimate the moisture content in the asphalt concrete in this paper. And, the electrical resistance of dense asphalt concrete is measured before and after soaking. Then, the mathematical relationship between absorbed moisture and electrical resistance of asphalt concrete is established. The absorbed moisture can be estimated using the electrical resistance of asphalt concrete. Results show that a linear relationship exists between the content of absorbed moisture and the logarithm of electrical resistance. The more the absorbed moisture is, the smaller the electrical resistance is. This method can be used to evaluate the dry/wet condition of asphalt pavement.