Using Blends of Construction & Demolition Waste Materials and Recycled Clay Masonry Brick in Pavement

Abstract

In Egypt and many developing countries, the use of Construction & Demolition (C&D) waste and Recycled Clay Masonry (RCM) brick materials as Unbound Granular Materials (UGMs) in pavement construction is generally very limited. There has been reluctance to adopt recycled materials in pavement construction. Despite the fact that there are allocated land fill areas for dumping this kind of waste, in Egypt C&D waste is usually dumped on the sides of canals, minor roads and at the entrance of the cities and towns. This causes environmental problems and affects the daily lives of people. Therefore, blends of C&D waste materials with RCM were evaluated for use as UGMs. The C&D waste and RCM materials were obtained from some dumps on the sides of roads and canals around Mansoura City, Egypt. The collected materials were crushed and mixed in the laboratory. The proportions of the C&D/RCM blends were 100/0, 90/10, 80/20, 70/30, 55/45, 40/60, 20/80, and 0/100% of the total aggregate mass. The characterization of C&D/RCM blends as well as the response to cyclic loading by Repeated Load Triaxial Testing (RLTT) was covered in this research paper. Static triaxial shear tests and RLTT were conducted using a Universal Testing Machine. RLTT and static triaxial shear test specimens were prepared at the optimum moisture content and compacted according to modified Proctor. RLTT were performed in accordance with the AASHTO T307 on triplicate specimens. RCM materials (100%) as UGMs failed to meet the requirements of Los Angeles Abrasion (LAA) test of 50% maximum as specified by the Egyptian Code of Practice (ECP). RLTT data showed that all C&D/RCM blends yielded high resilient moduli however, no significant variation in resilient moduli values were observed between the different C&D/RCM blends.