Some recent research on the hydraulic conductivity of road materials

Towards a mix design model for the prediction of permeability of hot-mix asphalt

“…The method of Vardanega et al [16] shares similar traits with those proposed by Khosla and Sadasivam [10] and Denneman et al [4] in that all methods have identified a particle or sieve size which best relates to permeability and the field performances of HMA, typically located within the meso range. These methods follow the principles of the Bailey and DASR methods which indicate that fine-graded mixtures tend to perform better than coarse-graded mixtures, as the coarser aggregates typically do not contribute to structural stability and increase the potential for the wall effect to dominate the permeability of the mixture.…”

“…AV(%) = percentage air voids D75 = the sieve aperture through which 75% of the granular material in the mix would pass Subsequent research [16] expanded the database with data from an additional ten publications and modified Equation 2 to consider mixtures of both NMAS ≤ 12.5 mm (Equation 3) and NMAS > 12.5 mm (Equation 4).…”

“…The model was trained with 90%, validated with 5%, and tested with 5% of the data respectively. The sixth phase aimed to independently verify the binary aggregate ratio methodology using the principles proposed by Vardanega et al [16],…”

“…A separate analysis, using the formula proposed by Vardanega et al [16], was conducted to evaluate and verify the permeability of USA and USB. A Probability Density Function (PDF) analysis was conducted, and the results are shown in Figure 3 below.…”

Comparison of Prediction Models for the Permeability of Granular Materials Using a Database

“…Lőrincz et al (2005) and Singh (2014) provide more extensive commentary on the origins and details of the 'grading entropy' approach. Using a similar database to that presented in Vardanega et al (2017), Feng et al (2018b) performed multiple linear regression analysis to a large database of hydraulic conductivity measurements on asphalt concrete using the grading entropy co-ordinates as predictors. Feng et al (2018a) performed similar analysis for a set of laboratory data on a single gravel and found Equation 8 8Like the 'Hazen' and 'Shepherd' approaches no measurement of void ratio is included in this approach.…”