Development of the Measuring Techniques for Estimating the Air Void System Parameters in Concrete Using 2D Analysis...

Area of Science:

• Materials Science
• Civil Engineering
• Concrete Technology

Background:

• Air-entrained concrete utilizes air voids to enhance durability and freeze-thaw resistance.
• Accurate determination of air void system parameters is crucial for quality control and performance prediction.
• Existing methods for air void analysis have limitations, necessitating exploration of advanced techniques.

Purpose of the Study:

• To evaluate the influence of image quality on the determination of air void system parameters in concrete.
• To assess the efficacy of 2D surface analysis for characterizing air voids.
• To compare 2D analysis results with established 1D linear traverse methods.

Main Methods:

• Preparation and scanning of concrete surfaces for 2D image analysis.
• Image processing techniques to isolate and analyze individual air voids.
• Application of the Schwartz-Saltykov method for 3D void reconstruction from 2D data.
• Comparison of 2D analysis results with the linear traverse (1D) method (EN 480-11).

Main Results:

• Image correction is essential for accurate void separation and defect removal.
• The specific surface of voids can be reliably calculated using equivalent diameter or perimeter.
• Reconstructed 3D air void distribution and micro-air content (A300) showed good agreement with 1D method results.
• The 2D surface analysis method demonstrated good correlation with the EN 480-11 chord length counting method.

Conclusions:

• Optimized image quality and processing are critical for reliable 2D air void analysis.
• 2D surface analysis provides a viable and accurate alternative to traditional 1D methods for determining air void system parameters.
• This study validates the use of 2D image analysis for assessing the air void characteristics of concrete.