Comparative laboratory measurement of pervious concrete permeability using constant-head and falling-head permeameter methods

The permeability characteristics is one of the most important properties of pervious concrete (PC), which represents the ability of water on the surface to drain through the pervious pavement structure. Its measuring is a sensitive key on the pervious concrete. Thus, this paper presents the experimental results of two commonly used laboratory test methods to measure the permeability of pervious concrete; namely falling-head (FH) method and constant-head (CH) method, to investigate the relationship between the examined methods and select the reliable method. Moreover, study the effect of aggregate gradation and ratio of cement to aggregate on the permeability of PC. Therefore, thirty-six groups of pervious concrete specimens with twelve different types of gradation and three kinds of ratios of cement to aggregates were prepared in this study. The comparison between the two methods to evaluate which method is more suitable includes: the precision, the cost of the experimental equipment, the convenience of the test operation process and the time required for the test. The results showed that the permeability values measured by the falling-head method were significantly higher than those measured by the constanthead method and it is more convenient compared to the constant-head method. Effect of aggregate gradation on porosity and permeability was examined in this study. Correlation between porosity and permeability was investigated, and a new model between FH and CH methods was established. (C) 2020 Elsevier Ltd. All rights reserved.