Author: Ryan J. RohnePublisher:
ISBN:
Category : Aggregates (Building materials)
Languages : en
Pages : 31
Book Description
This report analyzed the mix designs and permeability of 230 concrete mixes from Minnesota paving projects paved between 2004 and 2008. Concrete permeability was measured on cores according to ASTM C 1202, Standard Test Method for Electrical Indication of Concrete's Ability to Resist Chloride Ion Penetration. Previous studies showed that aggregate gradations conforming to the 8-18 gradation specification do not always produce denser graded aggregates or concrete with better properties (higher strength, better finishability, greater freeze-thaw durability) than gradations that do not meet the 8-18 specification. Based on box plots and descriptive statistics, granite produced concrete with lower permeability than limestone and gravel. According to the Student's T-test with a 95% significance level, 7-18 graded aggregate produced concrete with significantly lower permeability than 8-18 graded and cement source and contractor both also affected permeability. According to the Student's T-test with a 90% significance level, 7-18 graded aggregate produced concrete with significantly lower permeability than gap graded mixes.