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Extensive research has been conducted on the development of Slurry Infiltrated Fiber Concrete SIFCON and its characteristics. Fly ash was used as a binder in this study, and two different kinds of steel fibers—micro and hooked steel fibers—were used in the mortar in variable ratios (0, 6, 12, and 18) to examine the properties of SIFCON geopolymer concrete. The optimization of the geopolymer slurry texture, compression strength, hardness, ultrasonic pulse-velocity, elastic modulus (dynamic) (Ed), shear modulus (dynamic) (Gd), and the logical correlation among non destructive testing (NDT) (RN and UPV) and compression strength were all examined. The test outcomes demonstrated impoved characteristics, such as a 26.1% increase in compressive strength when 12% micro fiber of steel was used. The value of ultrasonic pulse velocity (UPV), which includes shear pulse velocity (Vs) and longitudinal pulse velocity (Vl) showed increases of 33.70% and 27.50% respectively, with the addition of 12% micro fiber of steel. Insertion of 12% hooked-end steel fiber, however, produced ideal rebound number readings. [ABSTRACT FROM AUTHOR]

The feasibility of coloring geopolymer concrete that uses slag as a binder was investigated in this work by employing inorganic pigments and examining the influence of the pigment on certain geopolymer concrete parameters. In geopolymer concrete, tests were carried out with the addition of two pigment types (cobalt blue and iron oxide red), at percent of 0, 2, 4, 6 and 0, 1, 2, 3 %, respectively, of the slag's weight. Values of slump, compressive strength, flexural strength, indirect tensile (splitting) test, permeability test and Fourier transform infrared spectroscopy (FTIR) test were obtained. It was found through the above tests that the optimum percentage of adding pigments is 1% for the red pigment and 2% for the blue pigment. It was concluded through the FTIR test that both pigments that were used in this research did not interact with the other components of the mixtures and did not affect the interaction of the components among themselves. [ABSTRACT FROM AUTHOR]

Space heating is one of air-conditioning sectors that consumes a huge amount of the electrical energy supplied to the house and has a major impact on emissions of greenhouse gases and corresponding global warming. Phase change materials (PCMs) are regarded as a possible solution for reducing the energy consumption of buildings by storing the heat and releasing it in certain times. The present study assists for the utilization of waxes as PCMs by attaching an enclosed space to the roof of the building where the wax is exposed to high solar intensity in order to melt, and then circulating the warm air to the room overnight for heating. Building considerations as well as thermo-physical properties of waxes have been taken and measured experimentally. Results have shown that these materials have a good potential for reducing energy demand and satisfy comfortable thermal conditions. The obtained results, from a rig model built for that purpose, showed that the indoor temperature with the using of waxes could increase by 3-6 oC at winter nights compared to that measured in a traditional one. Furthermore, a simulation program depended on degreedays method explained that the energy consumption could be saved up to 67%. In other words, waxes could submit encouraging suggestions to enhance the heating for energy efficient buildings and offer sustainable solutions. [ABSTRACT FROM AUTHOR]

Natural particles were mixed with polymer resin in this study. Walnut shells as a particles were used to create a composite material that was added to a binary polymer blend matrix, namely, epoxy/polyurethane (PU). Liquid PU was added to epoxy at a volume ratio of 15%. Furthermore, temperature (20 °C–50 °C) and the walnut shells particles (WSP) with volume fraction of (2.5%, 5%, 7.5% and 10%) were used to assess the mechanical and physical attributes of the material, hardness, impact strength and thermal conductivity. According to the findings, when temperatures were high, there was an increase in impact strength and a decrease in the hardness and thermal conductivity values. Meanwhile, an increase in the volume fraction of WSP caused an increase in hardness and impact strength and a decrease in thermal conductivity. [ABSTRACT FROM AUTHOR]

In this study, lightweight geopolymer concrete was produced based on slag as a binder and using two types of lightweight aggregates (the first type is pumice aggregate resulting from pumice stone crushing, and the second type is bentonite aggregate resulting from converting bentonite clay into aggregate through several stages). This concrete can be considered more environmentally friendly because of its use of slag as a binder and slag as it is known to all that slag is an industrial waste. After pouring the samples and completing the curing period, the compressive strength test was performed and two non-destructive tests (the ultrasonic pulse velocity test and the rebound number test), and then a relationship was found between the compressive strength on the one hand and the non-destructive tests on the other hand, and this relationship is considered very important to estimate the compressive strength of a structure or wall forming of the same type of concrete that has been subjected to certain conditions or dilapidated building through non-destructive tests. As for the best lightweight concrete mix, it is LBB, which contains fine aggregates of bentonite and coarse aggregates of bentonite with a grade (5-25), as it gave a compressive strength of 26.4 MPa. [ABSTRACT FROM AUTHOR]

Fly ash (FA) and cement kiln dust (CKD) are waste materials with a lot of promise in polyurethane (PUR) technology as modifiers of mechanical and thermal characteristics. The objective of this study was to investigate the effects of the addition of cement kiln dust and fly ash as fillings materials to the rigid polyurethane foam. Density, compressive strength, and thermal conductivity were studied. Foam density increases with increasing the two filling materials due to decreased cell size and foam volume. The compressive strength of the foams increased after adding low amounts of the two filling materials. A decrease in compressive strength was recorded at higher amounts of the filling materials due to the deterioration of the cell morphology. The thermal conductivity was decreased with increasing the percentages of the two filling materials. [ABSTRACT FROM AUTHOR]

The thermal properties of polyurethane foams are important to meet the government mandated energy efficiency goals. Polyurethane foams blown by traditional blowing agents such as water, n-Pentane, and Methyl formate may not have the thermal and mechanical properties to meet the target of the manufacturer. Over the last few years, Forane (FBA) was introduced as the fourth-generation of blowing agents that provide excellent insulation properties for the rigid polyurethane foams. One of the obstacles of using HFCF blowing agents was the high values of global warming and ozone depletion potentials. The current research provides a study of the effect of various blends of FBA 1233zd and traditional blowing agents on the mechanical and thermal properties of rigid polyurethane foam insulation. Foam samples were blown by 0, 25, 50, and 100% blowing agent blends were studied and the results show that for which extent foam properties were changed. [ABSTRACT FROM AUTHOR]