Abstract
Reuse of recycled concrete aggregates (RCA) in new concrete structures is limited due to their high water absorption and weak bonding to new matrix. These unfavorable properties are associated with the thin layer of old mortar attached to the surface of original aggregates. In this paper, a novel approach of RCA surface treatment by means of microbial carbonate precipitation (MCP) was studied. Factors influencing MCP on RCA were investigated. It was found that the amount of MCP peaks at pH = 9.5 and increases with higher temperature, bacteria concentration, or calcium concentration. Enhanced MCP on RCA can be achieved through proper control of culturing and precipitating conditions. Results show that surface modification of RCA through MCP is feasible evidenced by increasing weight and reducing water absorption of treated RCA.
| Original language | English |
|---|---|
| Pages (from-to) | 144-150 |
| Number of pages | 7 |
| Journal | Construction and Building Materials |
| Volume | 57 |
| DOIs | |
| Publication status | Published - Apr 30 2014 |
| Externally published | Yes |
ASJC Scopus Subject Areas
- Civil and Structural Engineering
- Building and Construction
- General Materials Science
Keywords
- MCP
- Microbial carbonate precipitation
- RCA
- Recycled concrete aggregates
- Surface treatment