الفهرس 
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Abstract
UHPC is a relatively recent concrete type developed in the past 20 years. It has a high binder content, low water-to-cement ratio (w/b), and high compression and tension strength. UHPC uses component material with microscopic particles carefully chosen for high-density packing. The particle size and distribution of the component materials should be appropriately determined to provide optimal mechanical and durability qualities. Additionally, the production of Portland cement increases CO2 emissions every year. Researchers experimented with substituting more cementitious materials with less cement. According to Wu et al., when 20% and 40% of the binder (cement) were returned with FA and GGBS, the lure had an impact on the flexural states of UHPCs Yu et al. reported that a UHPC matrix was built using 650 kg/m3 of less cement, which resulted in a 30% decrease in carbon emissions. Additionally, Amin et al. stated that silica fume and metakaolin were replaced with a small amount of cement to increase the strength of UHPC manufactured from ceramic wastes. The sustainability of UHPC was examined using Tahwia et al. 2021 GGBS and FA, two byproducts with high replacement percentages. UHPC comprises superplasticizers, steel fibers, and extra-fine powders (cement, quartz, sand, and pozzolanic additives). It is found that the matrix is incredibly tight, and it is because of this tightness that UHPC has such high strength and lifespan. For UHPC to be sustainable, complementary cementitious materials (SCMs), or sustainable materials, are required. These eco-friendly products may be made from recycled natural materials, industrial leftovers, or rubbish. Additionally, industrial waste materials (IWM) such as ceramic waste powder (CWP), brick waste powder (BWP), and marble waste powder (MWP) were used in this experiment. An extensive and varied laboratory investigation was conducted to examine the effects of employing various IWMs on the Portland cement with CWP, BWP, and MWP to achieve sustainable UHPC. Ten different concrete mixes were made from locally accessible ingredients, each with a minimum SF content of 15% and a cement replacement percentage of 0, 5%, 10%, and 15%. The mixtures were tested for slump flow, properties of hardened concrete, and sample shape with the required dimensions. Utilizing by-product materials with high replacement percentages could improve the sustainability of ultra-high-performance concrete (UHPC). This Study investigates the impact of employing ceramic, brick, and marble waste powder in place of Portland cement in UHPC. Portland cement (PC) weight was replaced with ceramic, brick, and marble waste powder with percentages of 5%, 10%, and 15%. Compressive strength and elastic modulus tests were performed to assess the outcomes of UHPC specimens. Using SEM and EDS analysis, the evolution of UHPC microstructural characteristics was investigated. Results showed that concrete with a 10% BWP as partially replaced cement substitution performed better in terms of compressive strength and modulus of elasticity, which reached 160.9 MPa and 39.64 GPa, respectively, at 90 days. Even with a 15% BWP replacement, concrete can still attain an ultra-high performance of 140.4 MPa. The high-density microstructure and, therefore, reduced ITZ thickness for the increased UHPC structure are revealed by SEM images and EDS analysis, which strengthened the outcomes of the permeability and compressive strength tests. The scanning electron microscopy (SEM) images of the UHPC samples’ small structures were used to make micrographs. EDS analysis and semiquantitative analysis were also done. Scanning electron microscopy (SEM-EDS, TESCAN VEGA3 XM) evaluated the surface morphologies and elemental distributions of particles. The analysis results indicated the atomic percentages of each element in the mixtures. Only the significant details were presented with the calculated Na2O/Si and Si/Al ratios. SEM and EDS analyses were conducted for seven days on new specimens. The chemical composition of the crushed samples was detected by thermogravimetric analysis (TGA, Rigaku Thermo Plus) between 30 C and 1000 C at a heat-up speed of 10 C min1. A coat of gold was applied to the broken specimens beforehand. X-ray diffraction patterns (XRD) were characterized to analyze the mineral constituent using a Bruker D8 Advance X-ray Diffractometer with Cu K X-ray radiation over a 2theta range recorded from 5 to 55◦ with a step size of 0.02◦. The parameters of the characteristic peak of crystalline phases were identified by Jade 5.0. Fourier Transformed Infrared Spectroscopy (FTIR) was evaluated by a Nicolet iS50 FTIR-ATR spectrometer in absorbance mode from 4000 to 400 cm11 at a resolution of 2cm1 one and a scanning speed of 5 kHz with 32 scans to measure the bonding structure of the phase. DSC/TG analysis was performed on a NETZSCH STA 449F3 simultaneous thermal analyzer with a controlled heating rate of 1°C/min from 3°C ℃ to 100°C ℃ in an atmosphere of flowing dry air to assist in the analysis of the behavior of the UHPC samples. This study discusses the findings and the impacts of industrial waste on workability, properties of hardened concrete, and microstructure properties. This study primarily combines ecologically friendly components to produce sustainable UHPC mixes. This study aims to clarify if employing various by-product materials as a partial substitute for the used PC may increase the sustainability of UHPC. To maintain a high level of sustainability for UHPC, industrial waste materials (IWM) such as ceramic waste powder (CWP), brick waste powder (BWP), and marble waste powder (MWP) were utilized as a partial replacement for PC. At 5%, 10%, and up to 15% of the binder mass, CWP, BWP, and MWP were used to produce the affordable UHPC. To make UHPC with high strength and high workable diameter, silica fume was used at 15% as a cement replacement. The goal is to define and establish the maximum replacement rates for sustainable materials at which UHPC may still operate at an exceptionally high level. Fresh, mechanical, and microstructure of sustainable UHPC were investigated. The following conclusions were extracted from the accomplished experimental tests. The flowability values of UHPC incorporating BWP gradually decreased and reached 161 mm, 156 mm, and 142 mm for BWP5 (5% BWP), BWP10 (10% BWP), and BWP15 (15%BWP), respectively. As a result, when BWP replacement was increased as opposed to PC replacement, UHPC fluidity increased, which was lower than the CWP15 mixtures. Normal UHPC had a 102 MPa strength in compression without steel fiber. The strength in compression of UHPC was improved (to 106 MPa) by 1% steel fibers. The maximum compressive forces were 76.0, 86, 121, and 151.80 MPa at 3, 7, 28, and 90, respectively, when the steel fiber concentration was 2%. The strength in compression of UHPC with 5% CWP was 111 MPa at 28 days and 130.2 MPa at 56 days, respectively. This was a DROP of 14.1 and 13.4% from the control mixture. It can be shown that UHPC’s strength in compression increased with CWP below 5%. This might be explained by the fact that CWP with pozzolanic activity can interact with CH to encourage cement hydration and generate more CS-H gel. The optimum CWP content for strength in compression is 10%, and the optimum CWP percentage for Strength in Tension is the same. CWP shouldn’t exceed 15% when using the Strength in Tension of CM2 as the benchmark. Compared to the control mixture, the 3-day Strength in Tensions of BWP5, BWP10, and BWP15 are 19.07%, 4.24%, 27.3%, and 14.83% lower. This is mainly because BWP integration decreases the amount of new hydration products in the UHPC mixture, decreasing the microstructure’s compactness. The optimum MWP for strength in compression is 10%, and the optimum MWP for Strength in Tension is the same. The maximum allowed MWP content relative to the control mixture is 15%. Additionally, the increase in strength in compression is less significant than the increase in Strength in Tension compared to the control combination. One explanation for this could be because concrete’s Strength in Tension is more susceptible to changes in ITZ characteristics and pore structure brought on by varying MWP content. The average water absorption values of the control mixture were obtained at 2.29% and 2.69% at 28 and 90 days. The water absorption values increased with brick waste content, obtained at 3.89% and 4.77% at 28 and 90 days.