Nondestructive assessment of the compressive strength of concrete with high volume slag

Abstract

Experimental research was performed to clarify the influence of slag content, type and particle size of coarse aggregate on the rebound value and compressive strength of concrete with high volume slag. Furthermore, a model of rebound strength curve for concrete with high volume slag was established. In addition, the porosity and pore structure of sample surface were analyzed by X-ray computed tomography (X-ray CT) and mercury intrusion porosimetry (MIP), respectively. The results demonstrate that the largest rebound value of the concrete is obtained when the content of slag is 40%. Furthermore, the particle size and type of coarse aggregate have an effect on the rebound value of concrete. When the coarse aggregate is basalt and the particle size is between 10–20 mm, the rebound value is the largest. In addition, when the carbonation depth is large, the rebound strength of concrete with high volume slag is larger than that of the national unified strength curve. The establishment of rebound strength curve of concrete with high volume slag is helpful to improve the accuracy of compressive strength test of slag concrete.