Durability of Concrete Made with Different Types of Aggregate Available in Bangladesh - Chloride Ingress

Abstract

In recent years, a good number of attempts are made in order to measure and test durability of concrete in various aspects. If such study and tests are properly performed, suitable materials along with their mix combination can be identified in order to make a durable concrete structure. Therefore, in this study, different types of binder materials and aggregates that are available in Bangladesh are tested in order to find proper aggregates for better durability. To perform this investigation, four different types of coarse aggregate (Brick Aggregate, Recycled Brick Aggregate, Black Stone and Shingles) and eight types of cement [Ordinary Portland Cement (OPC), CEM Type II B-M, CEM Type II B-MSL, 40% OPC – 60% SlagCEM IIIA, 80% OPC – 20% Slag(CEM II/A-S), 70% OPC – 30% Slag(CEM II/B-S), 30% OPC –70% Slag(CEM-IIIB), 15% OPC –85% Slag(CEM-IIIC)] have been used. Aggregates were collected and prepared according to grading requirements of ASTM C33-03. Several tests as specific gravity, absorption capacity, unit weight and abrasion resistance were performed for coarse aggregate. Cylindrical concrete specimens of diameter 100 mm and length 200 mm were made with different W/C ratio (0.45 and 0.5) and cement content (340 kg/m3 and 400 kg/m3). A total of 42 different cases were considered and a total of 546 concrete specimens were made for testing. The specimens were tested for compressive strength, stress-strain curve and Young's modulus at the age of 28 days and 60 days. Non-destructive test as Ultrasonic Pulse Velocity (UPV) were also performed. To conduct UPV test Portable Ultrasonic Non-destructive Digital Indicating Tester (PUNDIT) were used. The major objective of this study was to investigate the influence of different types of aggregate and different types of binding materials on Chloride Penetration through concrete. Due to time constraint, the mechanical properties of concrete for different types of aggregate and binding materials could only be measured. The significance of those results is discussed here. The research will be continued and data will be collected by RCPT and Chloride Ingress Test for measuring Chloride penetration through concrete.