تطوير تقنيات مختلفة في التبليط باستخدام مخلفات الزجاج

MODIFICATION IN DIFFERENT PAVEMENT TECHNIQUES USING WASTE GLASS MATERIALS

      Nowadays everything expands rapidly, grows, and develops to meet the demand of communities, including roads networks. The increasing number of cars, with increasing axle loads for modern automobiles, led to accelerating pavement deterioration. The current technology for paving and maintaining roads with Hot Mix Asphalt (HMA) could be the uneconomic solution for future. However, such technology has several disadvantages which are disagreed with sustainable, economics, and eco-friendly to environmental aspects. On the other hand, Cold Mix Asphalt (CMA), or more specifically Cold Bituminous Emulsion Mixture (CBEM) has several environmental and economic advantages over traditional HMA. However, it still has inferior mechanical and volumetric properties at early life compared to HMA if left without treatment. Therefore, the main aim of this study is to offer a new sustainable approach in asphalt technology, by characterizing CBEM with waste material and low energy preparation technique (Microwave technique).

     In this study, a trail has been made to develop the mechanical and volumetric properties of CBEM by double enhancement process. The first stage of the development included the developing of CBEM mechanical properties by replacing the Conventional Mineral Filler (CMF) with Ordinary Portland Cement (OPC) with three percentages are, 0, 50, and 100% from filler total weight in the mix. Then utilizing municipal solid waste material (crushed glass was selected) as fine aggregate (FGA) which was incorporated in 5 percentages; namely 0, 25, 50 75, and 100% as a replacement of virgin fine aggregates.

      Different mechanical and durability testing methods were performed to identify the variations in CBEM characteristics due to such incorporations; such as Marshall stability (M-S) and flow (M-F), indirect tensile strength (IDT), creep compliance (CC), wheel track (WTT), dynamic stability (DS), and Retained Marshall Stability (RMS).

     In terms of mechanical and durability properties, addition of 7%OPC filler to CBEM led to improve overall mix properties significantly. Where CBEM-100%OPC improved by about 2.15, 2.1, 9.28, 13.13, 1.74, 4.88, and 2.1 times of CBEM-CMF in terms of M-S, M-F, rutting resistance, DS, CS, IDT, and RMS, respectively.

    While the process of incorporation crushed waste glass (FGA) showed that incorporation of 100% FGA in addition to 7% OPC from aggregates total weight has made a significant improvement in mixture mechanical and durability properties, but mixture still contains high air voids.

    Thus, the second treatment stage was suggested to optimize air voids content in CBEM mixture utilizing low energy post-heating. The new mix of Half Warm Bituminous Emulsion Mixture (HWBEM) showed a novel properties compared to HMA. The HWBEM mix was improved by about 2.2, 8, 9.7, 1.3, and 2.9 times of HMA in terms of M-S, rutting resistance, DS, IDT, and RMS, respectively.

     Further, HWBEM incorporated 75%FGA showed a novel mechanical, durable, and volumetric properties, superior (and sometimes comparable) to HMA, and within the requirements of the Iraqi GSRB specification for surface layer, and for heavily traffic conditions. The developed mix called Half Warm Bituminous Emulsion Mixture (HWBEM) since it has prepared at 91 °C temperature.

    Accordingly, the main aim was achieved, and the newly sustainable asphalt mixture could be comparative to the well-known HMA. Although, this research work is deal with mechanical and volumetric properties characterization, but it worth to say that the new developed mix is cost effective and environmental friendly as it bases on low cost and low energy treatment.