Self-healing cementitious composites with a hollow vascular network created using 3D-printed sacrificial templates

Additively manufactured vascular networks have great potential for use in autonomous self-healing of cementitious composites as they potentially allow multiple healing events to take place. However, the existence of a vascular tube wall may impede with the healing efficiency if it does not rupture timely to release the healing agent. The...

Mechanical properties and healing efficiency of 3D-printed ABS vascular based self-healing cementitious composite: Experiments and modelling

Cracking is one of the main causes for deterioration of concrete structures. Self-healing concrete with 3D-printed vascular networks has excellent potential for autonomous self-healing. This approach is scarcely investigated: no studies have been devoted to the influence of printing parameters on the properties of vascular based self-healing...

Experimental study of flexural fatigue behaviour of cement paste at the microscale

This study presents an experimental investigation of fatigue properties of cement paste at the microscale. A strong size dependence is found for the flexural fatigue life of the cement paste specimen. Microscopic observations on the fractured surfaces suggest that there is a higher density of nano-scale cracks generated during the fatigue...

The role of rejuvenators in embedded damage healing for asphalt pavement

Rejuvenator encapsulation technique showed great potential for extrinsic asphalt pavement damage healing. Once the capsules are embedded within asphalt pavement, the healing is activated on-demand via progressing microcrack. When the microcrack encounters the capsule, the fracture energy at the tip opens the capsule and releases the...

Multi-scale characterization of lignin modified bitumen using experimental and molecular dynamics simulation methods

Lignin, as a major waste from biofuel and paper industries, could be utilized as a modifier to enhance the relevant performance of bitumen. However, the effects of lignin on the thermodynamics properties and molecular structure of bitumen are rarely studied. Meanwhile, the potential modification mechanism of lignin modified bitumen is still...

A study on the effect of ceramic polishing powder on the nucleation and growth of hydrates in cement paste

The production of cement leads to a large amount of CO₂ emission. Using industrial waste slag, such as ceramic polishing powder (PP), to replace part of Portland cement can reduce the pollution caused by the cement industry and solid waste disposal. In order to use PP as a replacement for cement, its effects on the properties of...

Lagged settlement in sandy cobble strata and earth pressure on shield tunnel

Lagged settlement is a typical accident induced by shield construction in sandy cobble strata. This paper analyzed the process and mechanism of lagged settlement, results show that all phases are in accord with the characteristics of ellipsoid theory of particle flows. Based on this theory, a method for calculating coefficient of lateral...