Mechanistic-Empirical Prediction of Rutting and Fatigue Cracking Life for Porous Asphalt Modified with Nano-Silica (Nano-SiO₂)

Department of Civil and Planning, Universitas Diponegoro, Semarang, Indonesia

^* Corresponding author: andimuflih@lecturer.undip.ac.id

Abstract

Porous asphalt is widely known for its excellent surface water drainage capabilities, but it has structural durability weaknesses that make it susceptible to damage such as rutting and fatigue cracking. One effort to overcome this problem is by adding nano materials such as Nano-Silica (Nano-SiO₂), but quantitative evaluation of its impact on the overall service life of pavement is still limited. Therefore, this study aims to predict the increase in service life against rutting and fatigue cracking damage in porous asphalt pavement modified with Nano-Silica. The method used is a mechanistic-empirical approach, where the dynamic modulus (|E*|) of the mixture is predicted from the rheological data of the binder, which is then used in the KENLAYER program with a hybrid model (linear/non-linear elastic) to calculate the critical strain. The main results show that Nano-SiO₂ modification successfully increased the |E*| value by 33.3%, which directly reduced the critical strain and increased the predicted service life of the pavement from 13.38 years (original mixture) to 14.25 years (modified mixture). However, it was also found that rutting in the weak subgrade layer remained the main failure mode that determined the performance of both types of pavements.