OasisLMS

Recycled concrete aggregates (RCAs) are obtained from concrete waste that is mostly collected from demolished concrete structures or reconstruction purposes. Due to the growing scarcity of natural aggregates, the use of recycled concrete aggregate (RCA) could be a worthwhile substitute, thus mitigating the need for landfill space and new aggregate quarries. Use of RCA started decades ago in non-structural applications. Research and development is now being conducted to determine how viable RCA is as replacement for conventional aggregate in concrete construction with the primary purpose of making construction more environmentally friendly. This course discusses how deficiencies of RCA concrete, with regards to lower compressive strength and durability properties, can be overcome in order to use RCA concrete in some applications, such as pavements. It also discusses how the use of RCA concrete improves internal curing and helps to reduce concrete autogenous shrinkage.

RCA is more porous, less dense, and has a greater water absorption capacity than conventional aggregate. However, in spite of lower strength qualities, laboratory testing has shown that RCA can be used in concrete construction. Because the qualities of RCA vary reasonably among diverse sources, there is also a concern about high chloride content in RCA obtained from the demolition of structures subjected to de-icing salts.

The contents of this course include five recorded presentations from the ACI 2015 Fall Convention:
• Long-Term Effects of Recycled Aggregate on Concrete Properties, by David Williams, CIM Student, NJIT 
• Flexural Behavior of Reinforced Concrete Beams Incorporating Construction and Demolition Waste, by Ardavan Yazdanbakhsh
• Internal Curing with Crushed Returned Concrete Aggregates for High-Performance Concrete, by Haejin Kim 
• A Review of the Applicability of Concrete Durability Test Methods for Use with Recycled Concrete Aggregates, by Matthew P. Adams

1. Demonstrate understanding of how concrete mixtures containing recycled concrete aggregate can achieve similar strength and durability properties as concrete with natural aggregates.
2. Recognize the different types of testing that could be performed on new concrete mixtures produced with recycled concrete aggregate.
3. Demonstrate knowledge of the various methods that suppliers of RCAs use to design and validate concrete produced by new recycled materials.
4. Describe emerging technologies in concrete produced with recycled concrete aggregate and its application in civil infrastructures in global markets.

Review and study the materials included in this module. Then, complete and pass the corresponding 10-question quiz with a score of 80% or higher to receive a certificate for 0.1 CEU (1.0 PDH).
Continuing Education Credit: 0.1 CEU (1.0 PDH)
Approved by AIA (LU/HSW) and ICC
Access Period: 30 days