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Performance of Capsules in Self-Healing Cementitious Material
Mouna A Reda1, Samir E Chidiac1
1Department of Civil Engineering, McMaster University, 1280 Main Street West, Hamilton, ON L8S 4L7, Canada.
Materials (Basel, Switzerland)
|October 27, 2022
Summary
Encapsulation enhances self-healing cementitious materials, but capsule survival during mixing is key. Finite element modeling shows capsule properties must match cement matrix behavior for effective healing.
Area of Science:
- Materials Science
- Civil Engineering
- Nanotechnology
Background:
- Encapsulation is explored for autonomous self-healing in cementitious materials.
- Capsule survival during mixing and controlled release upon cracking are critical challenges.
- Literature shows inconsistencies in self-healing capsule design and performance evaluation.
Purpose of the Study:
- To investigate compatibility requirements between capsules and cementitious materials.
- To understand the influence of cement volume changes on capsule integrity.
- To provide insights into observed inconsistencies in self-healing material performance.
Main Methods:
- A comprehensive literature review was conducted.
- A finite element model (FEM) was developed to simulate capsule-cement interactions.
- The model analyzed capsule behavior under cement hydration and drying volume changes.
Main Results:
- Finite element analysis revealed critical mechanical and geometrical compatibility requirements.
- Results highlight the importance of matching capsule properties with the cementitious matrix.
- The study provides explanations for inconsistencies reported in previous research.
Conclusions:
- Capsule properties must be compatible with the cementitious matrix for successful self-healing.
- Finite element modeling is a valuable tool for optimizing self-healing capsule design.
- Addressing these compatibility issues is essential for advancing self-healing concrete technology.
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