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Concrete Shrinkage Behavior Under Varying Degrees of Restraints Using DIC
Haolin Guo1, Yajie Zhang1, Runze Du1
1College of Aerospace and Civil Engineering, Harbin Engineering University, Harbin 150001, China.
Materials (Basel, Switzerland)
|August 13, 2026
Summary
Concrete restraint significantly increases tensile strain and cracking risk. Higher restraint levels inhibit shrinkage, leading to critical early-age cracking, essential for structural safety.
Area of Science:
- Materials Science
- Civil Engineering
- Structural Engineering
Background:
- Concrete shrinkage and cracking are critical issues affecting structural performance and durability.
- Understanding restraint effects is vital for early-age durability and structural safety.
Purpose of the Study:
- To investigate the influence of varying restraint levels on concrete shrinkage behavior.
- To quantify the relationship between restraint degree and shrinkage-induced tensile strains.
- To identify critical periods for shrinkage cracking.
Main Methods:
- Four distinct restraint levels (0%, 35%, 55%, 75%) were created using varying inner steel ring thicknesses.
- Digital Image Correlation (DIC) and internal strain gauges were used to measure strain evolution.
- Tensile strains at the outer surface and interior were monitored to assess cracking risk.
Main Results:
- Increased restraint levels significantly inhibited concrete radial shrinkage, inducing higher tensile strains.
- Surface strains exceeded interior strains due to drying gradients, with rapid strain evolution in the first 60 hours.
- A clear correlation was established between the degree of restraint and shrinkage strain development.
Conclusions:
- The study clarifies the relationship between restraint and concrete shrinkage, advancing quantitative design for crack resistance.
- Findings support the customized optimization of concrete materials for practical engineering conditions.
- Accurate prediction of shrinkage evolution under restraint is facilitated, enhancing structural safety.
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