Test method of asphalt mixture specimen density: Generally, the surface drying method (the water absorption of the specimen is not more than 2%) is used to measure the gross volume density; When the water absorption of the sample is less than 0.5%, the apparent density of the sample (commonly known as apparent density) can be determined by gravimetric method in water. When the water absorption of the specimen is greater than 2%, the gross bulk density of the specimen is determined by wax sealing method. For permeable mixture and open graded mixture with large porosity, the gross bulk density of the specimen is determined by volume method.

The standard temperature for testing the apparent density or gross volume density of asphalt mixture specimens is 25℃ 0.5℃.

Extended data 1) Bored core samples

Core sample diameter should not be less than φ 100. When the core sample drilled at one time contains different layers of asphalt mixture, the core sample should be sawed along the joint surface of each layer with a cutting machine for determination according to the structural combination.

2) Measure the density of the specimen.

(1) Gently brush the drilled test piece into water to remove the adhered dust. If there are loose particles on the corners of the sample, they should be carefully removed.

(2) Dry the sample or blow dry it with an electric fan for not less than 24 h until the weight is constant.

(3) According to the current test procedure, the apparent density or total volume density of asphalt mixture specimens is determined.

Baidu Encyclopedia-Test Code for Asphalt and Asphalt Mixture in Highway Engineering

China Education Purchasing Network-How to accurately measure the gross bulk density of the specimen? Method comparison