الفهرس 
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Abstract
In this study, eight blends of Construction and Demolition (C&D) waste materials with Recycled Clay Masonry (RCM) were investigated for use as Unbound Granular Materials (UGMs) for road construction in Egypt. The proportions of the RCA/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. These blends were characterized through a comprehensive experimental program. The experimental program consisted of routine and advanced tests. The routine tests included the Scanning Electron Microscopy (SEM)/Energy Dispersive Spectrometry (EDS) in combination with X-ray diffraction (XRD), Atterberg limits, AASHTO classification, modified Proctor, Los Angles Abrasion, California Bearing Ratio (CBR), specific gravity, water absorption, pH, hydraulic conductivity, and initial matric suction. Advanced tests i.e., static and Repeated Load Triaxial Testing (RLTT) tests were conducted on the investigated materials to characterize their behavior under traffic loading. Results showed that The RCM content had significant impact on both of the initial matric suction and the strength of the blend. Generally, a decrease in the initial matric suction, resilient modulus and CBR at OMC occurred with an increase in the RCM content. RLTT data of the investigated RCA/RCM materials were applied to the K-θ and universal models. The universal model was modified to incorporate the RCM effect, and hence a revised model for all blends was proposed. The proposed model yields accurate predictions with R2 of 0.82. Finally, performance in terms of rutting and fatigue cracking of seven pavement sections with the investigated blends as base/subbase layers, was predicted using the strains computed by the Multilayer Elastic Analysis (MLEA) software “Kenpave” along with the Mechanistic-Empirical Pavement Design Guide (MEPDG) models. Three different climatic conditions (Cairo, Alexandria, and Aswan) and two speeds of 10 and 50 mph were used in this analysis. The seven pavement sections were first designed by the AASHTO 1993 method for flexible pavements using different subbase materials (90/10, 80/20, 70/30, 55/45, 40/60, 20/80, and 0/100%). The 100/0 RCA/RCM was employed as base material in the seven sections over the subbase layer. A control section was designed based on a virgin aggregate as a base material. The hot mix asphalt (HMA) layer stiffness in terms of dynamic modulus, E* was predicted by using the NCHRP 1-40D modified Witczak model. The pavement performance of the sections with RCA materials as subbase/base layers was significantly better than the section with virgin aggregate.