The effect of hydrated lime on moisture susceptibility and aging of hot mix asphalt: mastic to mixture scale

Moisture damage is one of the most prominent distresses in asphalt mixtures, significantly limiting pavement performance and durability over its intended design life. To address this challenge, ongoing research focuses on improving the moisture resistance of asphalt mixtures by developing field-realistic testing protocols. This study is divided into two key components. The first part involves the development of a testing protocol for asphalt mastic using the Poker Chip test to evaluate its ductility and strength behavior. Mastic samples were prepared using two commonly available fillers in Illinois: hydrated lime and limestone mineral filler. Additionally, the influence of binder modification with hydrated lime was assessed. The results confirm that the Poker Chip test is feasible for mastic characterization, effectively capturing the ductility and strength properties influenced by filler type. Notably, hydrated lime increases mastic strength but reduced ductility across all aging levels, whereas mineral filler maintains ductility with decreased strength. Critical to this testing is the calibration of the mastic weight influencing the covered film thickness, both for Poker Chip and long-term lab aging. The second part of the study focuses on developing a field-realistic and anti-aging mixture-level test protocol. A modified Hamburg Wheel Tracking Device with layered specimens was used to evaluate the moisture susceptibility of asphalt mixtures containing hydrated lime. Results showed that hydrated lime substantially improved rutting resistance. However, in the IFIT cracking test, mixtures with hydrated lime exhibited lower Flexibility Index (FI) values, suggesting diminished cracking resistance. This reduction in FI may be attributed to the over-substitution of hydrated lime as a filler, which may offset its potential anti aging benefits.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Civil Engineering

Grantor

University of Illinois Urbana-Champaign

Year dc:date

2025

Author dc:creator

• Regmi, Bibek

Contributors dc:contributor

• Hajj, Ramez Muhammad

• Moisture Damage
• Asphalt Mastic
• Poker Chip
• Flexibility Index

Statement dc:rights

• Copyright 2025 Bibek Regmi

Language dc:language

en, eng

Handle dc:identifier

https://hdl.handle.net/2142/130211

OAI record oai:identifier

https://www.ideals.illinois.edu/oai-pmh?verb=GetRecord&metadataPrefix=etdms&identifier=oai%3Awww.ideals.illinois.edu%3A2142%2F130211