Multi-component analysis, molecular model construction, and thermodynamics performance prediction on various rejuvenators of aged bitumen

The molecular dynamics (MD) simulation method is proved as an efficient tool to explore the intermolecular interaction between rejuvenators and aged bitumen, but the simple “singlemolecule” model of rejuvenator would bring the inaccuracy to simulation outputs due to a huge difference with its realistic multi-component chrematistic. This study...

Toward the long-term aging influence and novel reaction kinetics models of bitumen

This study aimed to explore the long-term aging influence on chemo rheological properties and develop novel consecutive models for the long-term aging reaction kinetics of bitumen. The results revealed that the aging index was significantly dependent on the types of selected parameters. The Zero-order model was suitable to describe the long-term...

Chemical characterizations and molecular dynamics simulations on different rejuvenators for aged bitumen recycling

Molecular dynamics (MD) simulation is an advanced tool to explore the interaction mechanism between aged bitumen and rejuvenators at the nanoscale. However, the general MD molecular structures of rejuvenators led to the lower quantify and inaccuracy of the simulation outputs. This study aims at developing more realistic molecular models to...

Investigation of Polyurethane Modified Cold Bitumen for Fast Cold In-Place Recycling

Cold in-place recycling is gaining more attention worldwide because of its lower energy consumption, while the normally used asphalt emulsion and foamed asphalt cannot meet this requirement of short traffic disturbance and road performance of the surface layer. In this research, a polyurethane-modified cold binder (PMCB) was designed and...

Studying the impact of phase behavior in the morphology of molecular dynamics models of bitumen

Conventional Molecular Dynamics (MD) models of bitumen are built by homogeneously mixing molecules in a volume without considering that the molecules in bitumen are known to exhibit phase behavior and form distinctive molecular arrangements. These are known to have a significant impact in the behavior of bitumen, and considering their...

Aging and rejuvenation effects on the rheological response and chemical parameters of bitumen

The rejuvenation efficiency of aged bitumen is the main concern when developing rejuvenating agents. It is necessary to develop a method to assess the efficiency of rejuvenators using rheological parameters in the whole frequency region. To this end, the 2S2P1D micromechanics model is adopted to fit the entire G∗ master curves of various...

Unraveling the critical indicators for evaluating the high-temperature performance of rejuvenator-aged bitumen blends

This study aims to systematically investigate the influence of rejuvenator type/dosage and the aging degree of bitumen on the rutting resistance, flow behavior, and elastic/creep potential of rejuvenated bitumen at high temperatures. The rutting parameter (G*/sinδ), rutting failure temperature (RFT) from Linear viscoelastic test (LVE), zero...

Effect of mineral fillers on epoxy-modified open-graded porous asphalt durability

Epoxy-asphalt (EA) attracted the attention of road authorities in many countries as a solution for open-graded porous surface layers with enhanced durability and longevity. This research presents an experimental programme to assess the durability of epoxy-modified open-graded porous asphalt (EMOGPA) mixes, emphasising the effects of the...

Investigating the rheological properties and compatibility behaviours of RET/PE and WR/CR/ SBS compound-modified bitumen

Two types of elastomer/plastic compound-modified bitumen were developed by means of incorporating the reactive elastomeric terpolymer (RET) into the plastic (high-density polyethylene HDPE or recycled polyethylene RPE) modified bitumen and adding the wax residue (WR) into the bitumen/elastomer (crumb rubber CR or styrene–butadiene–styrene SBS)...

Insight into the critical evaluation indicators for fatigue performance recovery of rejuvenated bitumen under different rejuvenation conditions

This study aims to propose critical fatigue indicators for evaluating the restoration effectiveness of various rejuvenators on the fatigue performance of aged bitumen. The influence factors of rejuvenator type/dosage and aging degree of bitumen are involved, and different fatigue parameters from linear viscoelastic (LVE), linear amplitude sweep ...

Molecular dynamics simulation and experimental validation on the interfacial diffusion behaviors of rejuvenators in aged bitumen

This study aims to multiscale investigate the effects of rejuvenator type, temperature, and aging degree of bitumen on the diffusion behaviors of rejuvenators (bio-oil BO, engine-oil EO, naphthenic-oil NO, and aromatic-oil AO) in aged binders. The molecular dynamics (MD) simulation method is performed to detect the molecular-level diffusion...

Towards critical low-temperature relaxation indicators for effective rejuvenation efficiency evaluation of rejuvenator-aged bitumen blends

The relaxation behavior affected by aging and rejuvenation plays a crucial role in its low-temperature cracking potential of bitumen. However, there are limited studies on the relaxation performance of rejuvenated bitumen under different rejuvenation conditions. This paper aims to propose critical indicators to assess the rejuvenation efficiency...

Do different chemical and rheological properties act as effective and critical indicators for efficiency evaluation of rejuvenated bitumen?

This study investigates the impacts of rejuvenator type/dosage and the aging degree of bitumen on the chemical and rheological properties of rejuvenated bitumen, and propose critical chemo-rheological indicators for evaluating rejuvenation efficiency. Moreover, the potential connections between essential chemical and rheological indices of...

Introducing a force-matched united atom force field to explore larger spatiotemporal domains in molecular dynamics simulations of bitumen

This paper presents a United Atom (UA) force field for simulating hydrocarbon molecules in bituminous materials, integrating explicit hydrogens into beads with their parent atom. This method simplifies all-atom molecular models, significantly accelerating Molecular Dynamics (MD) simulations of bitumen by 10 to 100 times. Key advantages...

Role of thermodynamic relaxation on effectiveness of recycling agents on properties of aged bitumen

The low-temperature relaxation and fatigue cracking performance are two essential aspects in estimating the rejuvenation efficiency of recycling agents (RAs). This study aims to fundamentally investigate the effects of recycling agent type/dosage and aging degree of bitumen on thermodynamic and rheological properties of rejuvenated bitumen at...