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Thin-film transistor liquid-crystal display (TFT-LCD) waste glass can be used as a raw material for producing geopolymers, because it contains large amounts of silicon and aluminum in its amorphous structure. The setting time and compressive strength were evaluated to determine the quality of the geopolymer product with various amounts of nano-SiO2 (0%-3%) and TFT-LCD waste glass replacement (0% - 40%). The microstructures of the samples were characterized using mercury intrusion porosimetry (MIP), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The highest compressive strength and compact microstructure of the geopolymer was attained by adding 10% waste glass and 1% nano-SiO2. The results demonstrated that adding nano-SiO2 to the geopolymer substantially enhances compactness, improves uniformity, and greatly increases compressive strength. This work offers a low-cost route for fabricating geopolymers, because TFT-LCD waste glass can be used to partially substitute metakaolin in the composition of the geopolymer. [ABSTRACT FROM AUTHOR]

This study examined the characteristics of geopolymer with solar panel waste glass. After 28 days of curing, the compressive strengths of the geopolymer samples containing 10 mass % and 20 mass % solar panel waste glass were 63.3 ± 1.8 and 49.1 ± 2.2 MPa, respectively. The geopolymer sample with 10% solar panel waste glass exhibited a stronger reaction than that with 20% solar panel waste glass, and the strength decreased as the amount of solar panel waste glass increased. Thermo-gravimetric and differential thermal analysis (TG/DTA) results showed that the mass loss of geopolymer after heating declined as the amount of solar panel waste glass increased. The principal peaks in the Fourier transformation infrared spectroscopy (FTIR) spectra correspond to the Si-O-Al bond in geopolymer. Scanning electron microscopy (SEM) observations indicated that the microstructures of the stronger samples were more homogeneous, and the microstructures of geopolymer with 10% solar panel waste glass did not exhibit substantial deterioration. The experimental results indicate that solar panel waste glass has the potential to serve as a partial replacement of metakaolinite and exhibits favorable mechanic characteristics. [ABSTRACT FROM AUTHOR]

The development of the intelligent green building project (IGBP) is the pursuit of a business strategy of an enterprise in principle and the launch of the project in practice. For the effective attainment of the desired goal, the IGBP is integrated with the knowledge of construction project management and the application of the Project Definition Rating Index (PDRI) in order to combine the needs of pre-project planning. These are the steps to enhance the performance of project execution, make buildings energy efficient and reduce carbon emissions. The IGBP-PDRI model proposed to construct in this study is based on the life cycle of the engineering to set up different phases of work for process evaluation. The objective of each phase is subject to the work breakdown structure. The model of evaluation is divided into 4 sections, 11 categories, and 60 elements. The model has been tested empirically. Pre-project planning helps to forecast possible risks in the development of the project. In the course of project execution, quality requirement is satisfied through monitoring and control. These help to ensure the operation efficiency of the project, to the extent that the automated system of the building supported by green construction can meet the goal of sustainable development. [ABSTRACT FROM AUTHOR]

Effects of polypropylene (PP) fibers, steel fibers (SF) and hybrid on the properties of high-strength fiber reinforced self-consolidating concrete (HSFR-SCC) under different volume contents are investigated in this study. Comprehensive laboratory tests were conducted in order to evaluate both fresh and hardened properties of HSFR-SCC. Test results indicated that the fiber types and fiber contents greatly influenced concrete workability but it is possible to achieve self consolidating properties while adding the fiber types in concrete mixtures. Compressive strength, dynamic modulus of elasticity, and rigidity of concrete were affected by the addition as well as volume fraction of PP fibers. However, the properties of concrete were improved by the incorporation of SF. Splitting tensile and flexural strengths of concrete became increasingly less influenced by the inclusion of PP fibers and increasingly more influenced by the addition of SF. Besides, the inclusion of PP fibers resulted in the better efficiency in the improvement of toughness than SF. Furthermore, the inclusion of fibers did not have significant effect on the durability of the concrete. Results of electrical resistivity, chloride ion penetration and ultrasonic pulse velocity tests confirmed that HSFR-SCC had enough endurance against deterioration, lower chloride ion penetrability and minimum reinforcement corrosion rate. [ABSTRACT FROM AUTHOR]

Solid waste management is becoming a sustainability issue in highly industrialized societies. Recycling or reuse of solid waste is desirable to reduce the adverse impact of this material. The vast annual production of printed circuit board (PCB) waste in Taiwan creates environmental concerns because of the leaching of toxic chemicals into landfills. This study assessed the feasibility of utilizing resin powder and glass fiber recycled from PCB waste as a partial replacement of fine aggregate (natural river sand) in concrete. It also established a comprehensive test program to promote the use of recycling waste for waste reduction. The crushed powder of PCB mixed with standard mortar in fixed volumetric mix proportion, as sand:cement:water = 2.75:1:0.485 was the control group to test the fresh and hardened properties of the material. The test results of hardened specimen properties showed that the addition of PCB resin powder should be less than 10 %, and the addition level of glass fiber should be less than 2 %. The engineering properties and durability matched those of the cement mortar of the standard control group. Because toxic chemicals released from PCB powder and hardened concretes were found to be less than the tolerance limit in the local ordinances, waste PCB can be used in cement mortar, providing an alternative for recycling industrial waste PCB. [ABSTRACT FROM AUTHOR]

This paper focuses on the application of Fuller's ideal gradation curve to theoretically design blended ratio of all solid materials of high performance contrete (HPC), with the aid of error function, and then to study the effect of rice husk ash (RHA) on the performance of HPC. The residual RI-IA, generated when burning rice husk pellets at temperatures varying from 600 to 800°C, was collected at steam boilers in Vietnam. The properties of fresh and hardened concrete are reviewed. It is possible to obtain the RHA concrete with comparable or better properties than those of the specimen without RHA with lower cement consumption. High flowing concrete designed by the proposed method was obtained without bleeding or segregation. The application of the proposed method for HPC can save over 50% of the consumption of cement and limit the use of water. Its strength efficiency of cement in HPC is 1.4-1.9 times higher than that of the traditional method. Local standards of durability were satisfied at the age of 91 days both by concrete resistivity and ultrasonic pulse velocity. [ABSTRACT FROM AUTHOR]

Geopolymers are environmentally friendly substitutes for Portland cement; in many applications, geopolymers not only reduce green- house gas emissions but also are recyclable. The hardening mechanism of geopolymer polymerization differs from that of ordinary Portland cement. In the present research, two methods are used to evaluate the microstructure of this inorganic material. In the first method, complete polymerization was observed by means of scanning electron microscopy (SEM) to reveal the foundations of strength establishment. The SEM results show that the synthesized geopolymer maintained a layer structure of metakaolinite particulates. Therefore, it was thought that the geopolymeric reaction mainly occurred at the surface of microflakes of metakaolinite particulates. In order to further investigate the polymerization process of the material, two Raman spectrum frequency ranges--875 nm and 325 nm--were used in the study because of their capability to characterize the mineral/hydrated phases under a thick post-treatment layer. Also, in order to facilitate quality control of the production and explore the extreme compressive strengths of metakaolin cement, the polymerization mechanism and microstructures of the products were monitored step by step using Raman spectroscopy. The lessons learned in the research program can be used to advance the research methodology needed for further investigation of the strength enhancement of the geopolymer. [ABSTRACT FROM AUTHOR]