الفهرس 
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Abstract
Due to the ever-increasing demand for Egyptian stones on both a domestic and global scale, the ornamental stone industry in Egypt is continually expanding, which has resulted in the accumulation of massive amounts of waste in a variety of forms that can account for between 55 and 85% of the entire quantity throughout all stages of production. These wastes have become of hazardous effect on the surrounding communities due to the lack of proper management in recycling or even getting rid of these wastes in a safe mode. The present study aims to characterize and evaluate marble and granite wastes and determine their suitability for use in the production of hot asphalt mixes and self-compacting concrete mixtures. characterization of wastes The XRF, XRD, BET, and BT techniques were utilized to examine the physical characteristics, mineral composition, and chemical affinities of marble and granite waste. The studies revealed that about 90% of the particles are of grain size 70.77 μm for marble sludge, and of the used wastes 50.03 μm for granite sludge. Granite sludge has an average surface area of approximately 0.4493 m2/g, whereas that of marble sludge is about 0.6695 m2/g. Granite waste had a specific gravity of 2.82 g/cm3, while marble waste had a specific gravity of 2.73 g/cm3. The chemical analysis revealed that all used marble wastes are composed mainly of CaO with 53.21% content beside a very low content of MgO, SiO2, and Al2O3. In contrast, the primary chemical components of granite sludge are SiO2 of 70.526%, Al2O3 of 12.471%, K2O of 4.116%, and Na2O of 4.215 %, with minor amounts of Fe2O3 and CaO. Preparation of self-compacting concrete The preparation of SCC utilized both MPW and GPW up to 40% in place of cement. Eight different types of SCC mixtures, together with a control mix, were produced utilizing four different proportions of marble wastes (MP 10, MP 20, MP 30, and MP 40) and four different proportions of granite wastes (GP 10, GP 20, GP 30, and GP 40. The L-Box, slump flow, T50 cm, and the V-Funnel, in addition to fresh unit weight, were used to evaluate the properties of fresh SCC, including its capacity to pass and fill. The physical and mechanical characteristics, as well as durability performances, were evaluated throughout different periods of curing times for all of the concrete mixtures cured in water. According to the findings of the fresh SCC properties, the slump flow of both control and the other self-compacting concrete mixes ranged from 650 to 680 mm for marble addition and from 650 to 685 mm for granite addition, while T50cm slump flow ranged from 2.75 to 2.82 sec for marble addition and from 3.35 to 4.6 sec for granite addition. Regarding the concrete passage ability, the L-Box test results for both both control and the other SCC mixes ranged from 0.91 to 0.93 for marble addition and from 0.84 to 0.92 for granite addition. Furthermore, the values of the V-Funnel test of both control and the other self-compacting concrete mixes ranged from 4.71 to 7.05 sec for marble addition, and from 4.98 to 6.35 sec for granite addition. Wet unit weight measurements for the control and other selfcompacting concrete mixtures varied from 2.348 to 2.392 g/cm3 for marble addition and from 2.052 to 2.367 g/cm3 for granite addition. The findings of hardened SCC properties the other hand revealed that the water absorption at 28 days curing ranged from (0.33 to 0.84%) for marble addition and from 0.31 to 0.44% for granite addition, while the apparent porosity ranged from 0.82 to 2.05% for marble and from 0.76 to 0.99 % for granite addition. Moreover, the dry bulk density at the same curing time ranged from 2.443 to 2.499 g/cm3 for marble addition, and from 2.273 to 2.483 g/cm3 for granite addition. After curing for 28 days, the values of compressive strength of both the control and other SCC mixes ranged from 20.3 to 42.3 MPa for marble addition and from 13.2 to 42.6 MPa for granite addition. The results of tensile splitting strength for marble addition ranged from 2.08 to 3.27 MPa, while for granite addition they ranged from 1.63 to 3.34 MPa. After 30 days of being submerged in a sodium sulfate solution, the results showed that the compressive strength of the SCC mixes varied from 36.64 to 48.11 MPa when marble was added and from 22.44 to 47.31 MPa when granite was added, while after 60 days, the compressive strength ranged from 40.62 to 50.34 MPa for marble addition, and from 23.22 to 51.63 MPa for granite addition. In regards to the resistance of SCC to saline water, the findings revealed that the compressive strength after immersion in sea water for 30 days mixes ranged from 29.59 to 46.65 MPa for marble addition and from 26.13 to 53.38 MPa for granite addition, while after immersion in sea water for 60 days, the compressive strength ranged from 32.14 to 53.41 MPa for marble addition and from 27.28 to 53.20 MPa for granite addition. Following is a summary of the above findings: - The fresh property of the prepared SCC incorporating marble and granite wastes are found similar to that of control mix using up to 10% marble or granite wastes, while the increase in substitution resulted in a tiny decrease in the workability of SCC. However, the properties of fresh SCC in the different mixes with MPW and GPW are within the limits set by EFNARC. - There is a marginally slight rise in apparent porosity and water absorption with higher additions of marble or granite waste in comparison to the control SCC mix. - There is a negligible decline in bulk density in comparison to the control SCC mix as additions are increased. - The results of the mechanical properties were approximately similar to that of control mix up to 10% waste addition, while a further increase in waste addition, a reduction in strength was observed. - It was discovered that adding MP and GP to SCC mixtures that were submerged in a solution of magnesium sulfate and seawater improved their resistance to sulfate and saline aggressions. Preparation of asphalt mix modified with marble waste: The marble waste was used up to 100% substituting for ordinary mineral filler (Bag-house filler) in the preparation of hot - mixes asphalt. As well as the control asphalt mix, four other asphalt mixes were made utilizing the following different proportions of marble wastes: MPW/25, MPW/50, MPW/75, and MPW/100. The volumetric properties of prepared mixes were measured and the main findings are given in the followings points: - The results of Marshall stability of the control and the other prepared asphalt mixes with waste marble powder ranged from 762 to 1226 KN, while that of flow ranged from 3.2 to 3.9 mm. - The results of bulk density ranged from 2.413 to 2.446 g/cm3. - The Air voids (Va) of control and the other asphalt mixes with waste marble powder ranged from 5.23 to 6.11%. - The Voids in mineral aggregates (VMA) of control and the other asphalt mixes with waste marble powder ranged from 15.44 to 16.51%. - The range of the Voids Filled with Asphalt (VFA) for the control mix and the other asphalt mixtures containing waste marble powder was 63.01 to 65.97%. - The Moisture Susceptibility of control and the other asphalt mixes with waste marble powder ranges from 11.13 to 24.66%. - The optimal proportion of waste marble powder for blending is 4% by weight of the mineral aggregates. The above mentioned results may lead to the following conclusions: 1) The previous findings have led to the conclusion that the optimal proportion of marble and granite powder wastes to be used as cement replacement in manufacturing of SCC with better workability, physical, mechanical and durability performance was 10% waste powders regardless of waste powder type. 2) The addition of marble waste to hot mixes asphalt has led to: - An improvement in Marshall stability and flow. - A rise in the values of Gmb and VFA. - A slight decrease in the values of Va and VMA values. - A remarkable improvement in the results of stability loss. Overall, the results showed that all modified asphalt mixes with various proportions of MPW achieved acceptable values for all volumetric and mechanical properties according the Egyptian code of practice (ECP) for asphalt binder course.