Abstract-Industrial and urban development has resulted in the spread of plastic waste and the increase in the emissions of carbon dioxide resulting from the cement manufacturing process. The current research aims to produce green (environmentally friendly) concrete by using plastic waste as coarse aggregates in different proportions (10% and 20%) and nano silica sand powder as an alternative to cement in different proportions (5% and 10% by weight). The results showed that compressive strength decreased by 12.10% and 19.23% for 10% and 20% plastic waste replacement and increased by 12.89% and 20.39% for 5% and 10% silica sand replacement respectively at 28 days. Flexural strength decreased by 12.95% and 19.64% for 10% and 20% plastic waste replacement and increased by 11.16% and 19.86% for 5% and 10% silica sand replacement. Splitting tensile strength decreased by 12.74% and 20.22% for 10% and 20% plastic waste replacement and increased by 10.86% and 19.66% for 5% and 10% silica sand replacement. Dry density decreased by 4.51% and 7.83% for 10% and 20% plastic waste replacement and increased by 2.78% and 4.10% for 5% and 10% silica sand replacement respectively at 28 days.
A novel mixed natural coagulant has been developed to remove sewage pollutants and heavy metals from Qanat- al- Jayesh by using low cost adsorbent natural materials. In these materials, significant interaction contains Arabic gum mixed with extracted silica from rice husk ash (natural coagulants) by the Batch device approach, using two variables, pH values ranging from 5-8 and contact times between 0.25-5 hrs. All wastewater samples were collected after treatment by adsorbents and examined for determination of residual heavy metal concentrations: Pb, Ni, Zn and Cu by atomic absorption spectroscopy (AAS), turbidity, pH, total dissolved salts (TDS), electrical conductivity (EC) and total salinity (TS). The results obtained indicate Th
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This paper focuses firstly on the production of monomers bis (2-hydroxyethyl) terephthalate (BHET) and oligomers by using two different form of MgO light active and Nano Magnesium oxide with different weight ratio (0.15, 0.25 and 0.5) by using chemical recycling glass condenser at 190 ˚C. The second purpose is to study the effect of catalyst ratio, time of reaction and yield of products of the product. Elemental analysis for Carbon –Hydrogen and Nitrogen (CHN), differential scanning calorimetry (DSC), infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) have been investigated. Results indicated the catalytic activity was found to correlate with surface area; however, LA MgO has shown an exceptional activity, still it is h
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Fiber Reinforced Polymer (FRP) bars are anisotropic in nature and have high tensile strength in the fiber direction. The use of High-Strength Concrete (HSC) allows for better use of the high-strength properties of FRP bars. The mechanical properties of FRP bars can yield to large crack widths and deflections. As a result, the design of concrete elements reinforced with FRP materials is often governed by the Serviceability Limit States (SLS). This study investigates the short-term serviceability behavior of FRP RC I-beams. Eight RC I-beams reinforced with carbon-FRP (CFRP) and four steel RC I-beams, for comparison purposes, were tested under two-point loading.
Deformations on the concrete and crack widths and spacing are measured and
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The varied thermal conductivity (insulation) of silica aerogel with heating for different pH has been investigated, it has been depended on ambient pressure drying method in the preparing silica aerogel samples, also six different pH of samples (1, 2, 3, 7, 8 and 9) were treated under five degree of heating with (50,100,150,200 and 250) ᴼC. This technique is important to test the carry-outs hydrophobic silica to temperature without high-quality material changes in the basic characteristics. The hot-wire technique is used in this work to examine the thermal conductivity, Fourier Transform Infrared Spectroscopy (FTIR) depended to characterize the bonds and their artificial by heating. Resu
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From the sustainability point of view a combination of using water absorption polymer balls in concrete mix produce from Portland limestone cement (IL) is worth to be perceived. Compressive strength and drying shrinkage behavior for the mixes of concrete prepared by Ordinary Portland Cement (O.P.C) and Portland limestone cement (IL) were investigated in this research. Water absorbent polymer balls (WAPB) are innovative module in producing building materials due to the internal curing which eliminates autogenous shrinkage, enhances the strength at early age, improve the durability, give higher compressive strength at early age, and reduce the effect of insufficient external curing. Polymer balls (WAPB) had been used in the mixes of thi
... Show MoreBackground. Implant insertion in regions with poor bone quantity, such as the posterior maxilla, is potentially associated with an increased rate of implant failure. Calcium sulfate can be used as the coating material for commercially pure titanium (CpTi) and as the bone graft material around implants when bound to eggshell powder to enhance the bone quality and quantity of bone defect regions. This study performed a torque removal test to evaluate the effectiveness of eggshell powder as a bone substitute for filling bone defects around CpTi-coated implants coated with nanocrystalline calcium sulfate. Materials and Methods. Eighty screw implant designs were used in the tibiae of 20 white New Zealand rabbits. A total of uncoated 20 s
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When the flange of a reinforced concrete spandrel beam is in tension, current design codes and specifications enable a portion of the bonded flexure tension reinforcement to be distributed over an effective flange width. The flexural behavior of the RC L-shaped spandrel beam when reinforcement is laterally displaced in the tension flange is investigated experimentally and numerically in this work. Numerical analysis utilizing the finite element method is performed on discretized flanged beam models validated using experimentally verified L-shaped beam specimens to achieve study objectives. A parametric study was carried out to evaluate the influence of various factors on the beam’s flexure behavior. Results showed that
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