الفهرس 
Literature ReviewOnly 14 pages are availabe for public view
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Abstract
The aim of this research is to investigate the properties of four new sustainable multipurpose materials which are recent in the global market. The materials are a blend of Portland cement and mineral based lightweight aggregate which lack verification data. First, the microstructure of these materials is investigated using the XRF, XRD, SEM and EDS analysis in order to examine their composition. Then, characterization focused on porosity, dry bulk density, thermal conductivity, water vapor permeability, rate of water absorption, adhesive strength and mechanical properties as compressive, flexural, and tensile strength using standardized methods. To study the effect of fire, concrete cubes plastered with these materials are burned at different temperatures and their compressive strength is assessed after cooling. The experimental characterization highlights the difference between the four studied materials. Their performance is then compared with other traditional materials to translate their behavior and properties.
6.2. Conclusions
In light of the aforementioned findings, the following conclusions may be drawn:
a) Microstructural Analysis
1. The microstructural analysis confirms that the base of the studied materials is Portland cement due to the appearance of hatrurite (alite) in the 4 materials from the XRD analysis despite its different ratio, which is the major and characteristic phase in Portland cement.
2. CP_1 and CPQ_4 showed approximately the same SiO2 percentage from the XRF analysis, this is confirmed by the appearance of expanded perlite in the SEM images which is known by its high silicon content and used as a lightweight aggregate.
3. High silicon quartz grains are recognized in the SEM images of CPQ_4 which is in line with the appearance of quartz (coesite) phase from the XRD analysis. This confirms the utilization of quartz powder as a partial replacement of cement in the composition of CPQ_4.
4. CPA_3 shows a much porous microstructure than the other 3 materials. Although it showed a low SiO2 percentage from the XRF analysis, however expanded perlite grains appear in the SEM images. This confirms that it is used with a less percentage than in CP_1 and CPQ_4.
5. CC_2 shows a different composition with a much denser microstructure. The EDS and XRF analysis show that it is rich in calcium along with the appearance of calcite phase from the XRD analysis. This is confirmed by the appearance of bulk grains which are rich in calcium from the SEM images and can be identified as calcite grains.
b) Material characterization
1. CC_2 exhibits the highest density value of 1.3 gm/cm3 and the lowest porosity percentage of 7.39% due to the incorporation of CaCO3. subsequently, CC_2 possesses superior mechanical properties compared to the other materials, the highest diffusion resistance factor of 22.65, because its tightly closed pores let very little vapor to pass through, the lowest rate of water absorption and highest adhesive strength of 0.32 MPa. However, due to its dense microstructure, it shows the highest coefficient of thermal conductivity of 0.252 W/m.K.
2. The incorporation of expanded perlite in CP_1, CPA_3 and CPQ_4 increases their porosity percentage with values ranging from 30% to 48%, due to its highly porous structure. As a result, CP_1, CPA_3 and CPQ_4 demonstrate a much lower density value than CC_2; the differences are 0.43, 0.39 and 0.49 gm/cm3, respectively. This is reflected on their low coefficient of thermal conductivity of 0.08 W/m.K. However, CP_1, CPA_3 and CPQ_4 possess low mechanical properties, a low diffusion resistance factor, ranging from 9 to 13, and low adhesive strength ranging from 0.07 to 0.17 MPa compared to CC_2.
3. Plastering the concrete specimens with the studied materials increase their residual compressive strength by a minimum percentage 56% and maximum percentage of 146% at 550 °C and a minimum value of 3 times and maximum value of 9 times at 850 °C.
4. Doubling the coating thickness is effective at 550°C, 850°C. However, it shows no effect at 1000 °C.
5. Specimens coated with CPQ_4 show approximately no loss in the compressive strength due to the incorporation of quartz powder and expanded perlite. Also, specimens coated with CPA_3 show slight decrease in the compressive strength due to its high porosity and utilization of expanded perlite.
c) Comparative Study
All the studied materials show multiple insulating properties when compared to the other common materials.
1. The studied materials in this research demonstrate lower thermal conductivity value than cement, EPS, and gypsum plasters by a maximum percentage of 90% and a minimum percentage of 10%. Yet, they show higher thermal conductivity than BIMS plaster by a maximum value of 3.5 times and minimum percentage of 17%.
2. The studied materials exhibit higher diffusion resistance factor than the other materials by a maximum percentage of 126.5% and a minimum percentage of 33.62%. CPA_3 shows approximately an equal value to cement plaster.
3. CC_2 offers the highest compressive strength up to eight folds higher than the BIMS plaster and three times higher than cement and EPS plasters. CP_1 and CPQ_4 show approximately the same compressive strength as BIMS plaster. CPA_3 exhibits the lowest compressive strength of 0.51 MPa.
4. CP_1, CPA_3, CPQ_4 and the BIMS plaster can be considered to have a semi-equal dry bulk density value ranging from 0.3 to 0.5 gm/cm3. Also, CC_2, EPS and gypsum plasters show comparable densities ranging from 1.1 to 1.3 gm/cm3. Cement plaster demonstrates the highest density of 1.6 gm/cm3.
5. All the studied materials show lower adhesive strength than cement plaster, BIMS mortar and gypsum plaster, except CP_1 and CPQ_4 which show higher strength than gypsum plaster.
6. A maximum of 22% in compressive strength is lost at 550°C and 81% at 850°C for coated specimens with the studied materials. This represents a 45% and 100% higher performance for specimens coated with gypsum, respectively.