Much construction waste is produced during demolishing old buildings. We have considerable interest in recycling part of the construction waste because it is a cause of environmental pollution. So, research and development concerning recycling technology from waste aggregate and dust from waste concrete is constantly increasing. In this study, we manufactured a modified sulfur concrete (MSC) that has superior physical properties such as compressive strength above 78.4 MPa and degree of absorption below 0.5%. MSC is a mixture of modified sulfur, waste aggregate and dust from waste concrete. The modified sulfur is prepared by reacting for 4 hours in a chamber at 140 degrees C after mixing dicyclopentadiene (DCPD), oligomer and lowgrade sulfur. As a result of a chemical resistance test for 3 months of the synthetic MSC using recycled aggregate/dust and Portland concrete, a general concrete was seriously corroded and destroyed but the MSC was almost unchanged in weight and exterior appearance. The MSC will, therefore, be utilized as a concrete material for repair/reinforcement work because it has superior chemical resistance and a fast hardening ability.

Keywords: waste aggregate; modified sulfur; recycling technology; modified concrete