A variational free-discontinuity formulation of brittle fracture was given by Francfortand Marigo [1], where the total energy is minimized with respect to the crackgeometry and the displacement field simultaneously. The entire evolution of cracksincluding their initiation and branching is determined by this minimization principlerequiring no further criterion. However, a direct numerical discretization of themodel faces considerable difficulties as the displacement field is discontinuous inthe presence of cracks.

A Continuum Phase Field Model for Fracture

Morphology, rheology, and physical properties of polymer-modified asphalt binders

Molecular dynamics study of oxidative aging effect on asphalt binder properties

Using waste plastic bottles as additive for stone mastic asphalt

This study presents the development of fly ash-based geopolymer mixtures for 3D concrete printing. The influence of up to 10% ground granulated blast-furnace slag (GGBS) and silica fume (SF) inclusion within geopolymer blends cured under ambient conditions was investigated in terms of fresh and hardened properties. Evolution of yield stress and thixotropy of the mixtures at different resting times were evaluated. Mechanical performance of the 3D printed components was assessed via compressive strength measurements and compared with casted samples. SF demonstrated a significant influence on fresh properties (e.g. recovery of viscosity), whereas the use of GGBS led to higher early strength development within geopolymer systems. The feasibility of the 3D printing process, during which rheology was controlled, was evaluated by considering extrusion and shape retention parameters. The outcomes of this study led to the printing of a freeform 3D component, shedding light on the 3D printing of sustainable binder systems for various building components.

Investigation of the rheology and strength of geopolymer mixtures for extrusion-based 3D printing

Using surface free energy method to study the cohesion and adhesion of asphalt mastic

Internal structure evolution of asphalt mixtures during freeze–thaw cycles

Molecular dynamics provides a powerful tool to understand the elusive structure–performance relationship of asphalts. The combined molecular models were selected to investigate the interactions of the saturate, aromatic, resin, and asphaltene (SARA) four fractions and the correlation between fractions and the “bee-like structures” by atomic force microscopy in asphalts. The results showed that van der Waals was the main force to control intermolecular interactions. The arrangement of SARA fractions largely conformed to the modern colloid theory. However, some alkanes, sulfides, and condensed aromatics had different behaviors. Long-chain alkanes inserted into layers of asphaltenes, and small sulfides without long alkyl chains adhered to large sulfides or asphaltenes; nevertheless, counterpart condensed aromatics became much closer to those molecules. Strong interactions between the dispersed phase and continuous phase generated a larger size and greater number of “bee structures”. Asphaltenes played as a c...

Yiqiu Tan

Papers

Using surface free energy method to study the cohesion and adhesion of asphalt mastic

Internal structure evolution of asphalt mixtures during freeze–thaw cycles

Investigating the Interactions of the Saturate, Aromatic, Resin, and Asphaltene Four Fractions in Asphalt Binders by Molecular Simulations

Laboratory performance of warm mix asphalt containing recycled asphalt mixtures

Effect of WMA-RAP technology on pavement performance of asphalt mixture: A state-of-the-art review