Accurately determining the frequency response of asphalt pavement under vehicle live loading and thereby selecting an appropriate mixture modulus is crucial for improving the accuracy of calculating the pavement's mechanical response. This paper obtained the period of the vehicle load applied on the RIOHTRACK full-scale ring road by fitting the ring road's measured stress versus loading time data through a sinusoidal function, then presented the ring road's frequency response according to the conversion relationship between frequency and period and finally investigated the statistical relationship between frequency and depth as well as temperature, meanwhile presenting a model to predict the pavement's frequency under various depths and temperatures. The findings of this paper provide significant support for selecting an appropriate modulus parameter for asphalt pavement mechanical response calculation and will enhance the analytical level of pavement response calculation.
Hot-mix asphalt releases volatile organic compounds (VOCs) during production and paving, posing risks to occupational health and urban air quality. Existing studies commonly use qualitative or semi-quantitative analyses, limiting accurate emission assessment. This study developed a gas chromatography-mass spectrometry method using compound-specific internal-standard calibration to quantify organic gaseous emissions from asphalt. The method showed strong analytical performance, with calibration coefficients of determination ranging from 0.979 to 0.999, a mean recovery of 97.44%, a relative standard deviation of 0.65%, limits of detection of 0.008-0.273 mg/m & sup3;, and limits of quantification of 0.027-0.909 mg/m & sup3;. It enabled trace-level quantification of benzothiazole, a characteristic emission from crumb rubber-modified asphalt that is often overlooked. The method reduces matrix interference and improves reproducibility, providing a reliable tool for emission characterisation, exposure-oriented assessment, and low-emission asphalt development.
