Lignin fibers typically influence the mixture performance of stone matrix asphalt (SMA), such as strength, stability, durability, noise level, rutting resistance, fatigue life, and water sensitivity. However, limited studies were conducted to analyze the influence of fibers on the percent voids in mineral aggregate in bituminous mixture (VMA) during the mixture design. This study analyzed the e...

The influence of three material factors, namely asphalt-aggregate ratio, fiber-aggregate ratio and mineral filler–aggregate ratio (filler–aggregate ratio) on Marshall indexes of the lignin fiber SMA mixture are investigated in this study. To achieve this goal, orthogonal experiment design and implementation of Marshall stability test, residential stability test and rutting test were used to ana...

asphalt modification/reinforcement has received considerable attention as viable solutions to enhance flexible pavement performance. this is mainly prompted by the unsatisfactory performance of traditional road materials exposed to dramatic increases and changes in traffic patterns. this paper presents the evaluation of fatigue behaviour of nano reinforced stone mastic asphalt mixtures. fatigue...

The National Center f’or Asphalt Trchnolofiy (NCAT) has just complctd two Nation;ll Coopwrrive HicThw:tv Rr<e:lrch Pq!ram (NtHR6) Projects: NCHRP 9-X. “Designing Stone Matrix Asphalt (SMA) Mixtures.” and NCHRP 9-9. “Reilnement of Superpave Gyratory Compaction Procedure.” Dr. Ray Brown. NCAT director. was the p r i n c i p a l invcsti:etor on both pmjects. The fint project on SMA represented ;I ...

This report presents the comparative life cycle assessment (LCA) between warm stone mastic asphalt (SMA) and conventional SMA. Specifically, the study evaluated and compared the life cycle environmental and economic performances of two mixtures: a warm SMA binder course mixture with a chemical additive and a control hot SMA binder course mixture. Both of these mixtures were utilized as part of ...

The National Center for Asphalt Technology (NCAT) has undertaken a wide range of hot mix asphalt (HMA) related research projects. These projects have been funded by various agencies such as the National Cooperative Highway Research Program (NCHRP) of the Transportation Research Board, the Federal Highway Administration (FHWA), the Alabama Department of Transportation, the South Carolina Departm...

We report experimental studies on small angle light scattering (SALS), and rheodielectric and electrorheological properties of a binary mixture of octyloxy cyanobiphenyl and hexyloxy cyanobiphenyl liquid crystals. The mixture exhibits nematic (N) to smectic-A (SmA) phase transitions, and then again to a reentrant nematic (N(R)) phase transition. Rapid shear thinning in the quenched samples in t...

It is well known that the performance of hot mix asphalt (HMA) in service life is closely related to a proper aggregate gradation. A laboratory study was conducted to investigate the effects of nominal maximum aggregate size (NMAS) on the performance of stone matrix asphalt (SMA). The volumetric characteristics and performance properties obtained from wheel tracking tests, permeability test, be...

Methods of preparing test specimens in laboratories are particularly important. It also holds true in terms of compaction procedure in predicting pavement performance. The currently available laboratory compactor cannot adequately replicate field compaction conditions, especially the Stone Mastic Asphalt (SMA) mixture. The essential element of SMA mixture comprises of stones that are placed nex...