Advanced Materials Research Vol. 740

Abstract: Alumina-zirconia composite is an engineering material with a great potential to be develop for application as high temperature resistance structural material. In this research, zirconia toughness alumina (ZTA) was produced by physical interaction between Al₂O₃ powder and Y₂O₃-ZrO₂ powder. Two composition of powder with different Al₂O₃: Y₂O₃-ZrO₂ ratio was used, 70:30 and 80:20 by weight. Two different compaction methods, i.e. uniaxial pressing and cold isostatic pressing (CIP) with a maximum load of 150 MPa were used in this research to investigate the differences in properties of composites. Sintering process was done at four different temperatures with the heating rate is 5 o C/ min with a soaking time of five hours. Mechanical testing, i.e. compressive strength and hardness was performed to all samples. The microstructure analysis using a Scanning Electron Microscope SEM was also studied. From the result, the composite with the ratio of 70:30 showed better mechanical properties as compared to 80:20 composite. Addition of zirconia in the composite gave an increased in toughness due to transformation toughening mechanism of tetragonal to monoclinic phase. As a conclusion the composites produced high compaction green density will improved the sintering process, resulting in improved mechanical properties.

Abstract: The main focus of this research is to study the strength of concrete with ceramic waste as coarse aggregate. The sources of ceramic waste are obtained from the industrial in Malaysia. Presently, in ceramics industries the production goes as waste, which is not under going the recycle process yet. The potential of recycled ceramic waste as a substitute for coarse aggregates in concrete has been investigated. The recycle ceramic waste as aggregate was used. Concrete mixes with a 28 days characteristic strength of 20 MPa were prepared using water/cement ratio of 0.4, 0.5 and 0.7. The strength development of the concrete mixes containing recycled ceramic waste aggregates was compared to that of conventional concrete. The result show that the concrete mixes containing recycled ceramic waste aggregates achieve strength levels between 80 to 95 % compared to the conventional concrete. This indicates that the recycled ceramic waste has a potentially to be used as coarse aggregates for concrete.

Abstract: Natural fibers reinforced polymer composites have gained more interest because of their biodegradable, light weight, less expensive sources, easy processing, high specific modulus and also environmentally friendly appeal. This paper presents an overview of a study aimed at showing on how the bio-composites which is bagasse fibers combined with resins as an alternative of bagasse-fiber-based composites panel. Transforming bagasse fibers into panel products provides a prospective solution. Bagasse-fiber-based composites offer potential as the core material replacing high density and expensive wood-based fiberboard. Biodegradable composites reinforced with bagasse fibres after being modified or treated by alkali treatment were prepared and also the mechanical properties were investigated. The bio-composites panel samples were processed by hot press machine. All panels were made with aspect ratios between bagasse fibers and polystyrene thermoplastics resins and also the sieve size of bagasse fibers which has short fibers and combination of short fiber and granules fibers. The polystyrene was added as a modified from natural fibers to determine the effect it had on physical and mechanical properties of the panel. Resin content level and panel density were very important in controlling the strength properties of the panels. Surface hardness value, compressive strength, bending strength and bending modulus values all increases in resin content level and panel density. Bagasse-based-panel products can be commercialize successfully if have good development of a cost manufacturing process on an establishment of a market base for the products.

Abstract: Hot compression tests of 7075 extruded bar were carried out on the Gleeble-1500 thermal simulation machine at strain rates of 0.1 s-1 and 1s-1 and at temperatures of 320°C. The compression direction are aligned at 0°, 45°and 90°to the axis direction of the extruded bar. Microstructure and texture was characterized using Optical Microscopy and x ray diffraction analysis. The results show that the true stress of all specimen increases with decreasing temperature and increasing strain rates. Both the yield strength and the stable flow stress of the 0° specimens is the highest among all three specimens, while that of 45° specimen is the lowest. This could be attributed to the lamellar grain structures and the texture of the extruded bar. The microstructure of 0°specimen are of equiaxed grain due to dynamic recrystallization after compression, while the grain shape of 45°and 90°specimens are still of lamellar grain structure.

Abstract: In order to study the applicability of pipe piles in Tang-Cao expressway, shaking table model test was carried out. The results shows that, the internal force distribution of the pile under the action of seismic wave is basically the same with the behavior that is under the action of sine wave ; in the position of the 4 times pile diameter (distance the top of the pipe model about 200mm) appears the maximum axial force and bending moment; the change of the additional axial force in the upper portion of the pile is more complex, and tends to increase downward; the change of the moment tends to stable blow the distance of 20times the pile diameter from the pile top (distance the top of pipe model about 1000mm)

Abstract: The material properties of FGM beams are assumed to vary continuously through the thickness according to power law distribution. Based on the assumption that plane section remains plane and normal to the beam axis, the differential equations of motion were established for free vibration of FGM elastic beams under thermal loads and mechanical loads on the premise of the middle plane strain caused by heterogeneity of the materials. Natural frequency and dominant mode shape of FGM beams with four kinds of boundary conditions were obtained.

Abstract: In many areas, there are still a development road construction materials, traditionally, often use reinforced concrete, asphalt and other adhesive method to strengthen the low strength of rock and soil anti-freeze expansion coefficient; And now all countries in the world are studying how to use industrial production waste development of new composite materials. One of the most development potential, the production of industrial waste - slime. This paper USES the Russian kazan national construction university experimental methods, in the experiment to improve frost heaving soil physical and mechanical properties of the method for the synthesis of adhesive, based on the feasibility and applicability, environmental assessment of research and analysis, for the use of adhesive put forward a lot of reference value.

Abstract: Albania is relatively rich with low up to the middle enthalpy, with waters coming out as natural springs (12 springs) and wells (10 wells). The water temperature blowing out of the wells varies from 34°C up to 65.5°C to Kozani-8, the most important among the Albanian geothermal wells. It had been drilled in 1989. Finding of the hot brine was considered and accident at that time, as the well had been designed and drilled to search oil &gas. The well is located on the hills, 26km SE of Tirana. It encounters limestone strata at 1819m, penetrating over 10m into this section. The yield of the well is 10.3 l/s, and is presented stable from more than 23 years. The geographical position of the well, placed in the middle of a village, very close to the Corridor 8, are some of the most important parameters on choosing these waters for our designs and the related calculations. The recreational center provides the cascade and integral use of the Kozani-8 geothermal water, but not only. It also provide the electricity generations, through a hybrid system. The center will be also equipped with SPA, open and closed pools, fitness, massages, greenhouse & also aquaculture pools. The economic analyses, based on the NPV calculations, shows that this resource is completely competitive, and is unjustified its further waste. Despite the fact that the investment is too high (over 5.5 million Euro), it is completely feasible, and this is proven also by the risk analyses. It will also help on improving the living standards for the local community.

Abstract: The methods are considered for analytical data processing by measurements in heat supply systems. These methods are oriented to the solution of practical problems in the heat-power engineering by using the information-analytical systems. The possibilities of regression analysis for effective heating control and diagnosis of the measuring equipment are shown.

Abstract: With the quick development of economy, increase o f population and urbanization, urban water security becomes a limited factor to fulfill the urban sustainable development. Qinhuangdao is a water shortage of resources and pollution-induced water shortage city. Under the major background of global warming, the climate of Qinhuangdao becoming warmer and drier in recent years, the precipitation has decreased correspondingly. The rivers runoff reduces obviously and the level of the groundwater drops. The quantity of usable water resource is reduced significantly. Impacted by the urbanization, social-economic development and rapid population growth, the demand of water resource increases continuously. The security situation of water resource in Qinhuangdao is becoming more severe. Through analyzing the water resource situation, existing issues and reasons in Qinhuangdao city, the author proposed regulating approaches to ensure safety of water resources.