Effects of the crack geometric features on the probability density of spherical healing agent particles in concrete

Abstract

Accurately assessing and predicting the probability distribution characteristics of the healing agent particle on the crack surface is the prerequisite for the design of self-healing concrete. To accurately evaluate the probability distribution features, probability density function models considering the geometric characteristics of cracks were established for different healing agent particles and verified by a large-scale sample size test. The results showed that the distribution of the healing agent particle in concrete was consistent with a Binomial distribution. Poisson approximate was applicable to small size and large added quantity of healing agent particles while Normal approximate was applicable to large-size and low-dosing quantity healing agent particles. Aggregates would have an impact on the geometric characteristics of cracks, increasing the amount of healing agent particles distributed on the crack surface and the variance. To guarantee the healing effect, a calculation method for the theoretical dosage of the healing agent particle with a 95% confidence level was established. The research work provides a basis for the quantitative design of self-healing concrete.