30 cubic meters batching, delivering, and pouring of activated fly ash concrete

ABSTRACT: Mae Moh power plant (Thailand) has expelled fly ash more than 1.5 million tons each year for almost 2 decades. Around two thirds of them was managed to sale in cement and concrete industry. The Minority of fly ash was sale to other industries such as fertilizer. The deeper coal mine lead to the fly ash become high CaO and free. The leftover fly ash has sent to landfill because it failed to meet Thai standard specification of using fly ash in concrete. Electricity Generating Authority of Thailand (EGAT) has sought the sustainable way to maintain the use of fly ash in cement and concrete industry. So, EGAT begin pay attention to alkali-activated fly ash concrete as pilot project. It aims to enhance the turning research to be commercial product. The pilot project was set up in the power plant area with 120 square meters (30 cubic meters) of alkali-activated fly ash concrete. It was planned to overlay in a truck yard which was 20 minutes far away from the batching plant. Several mixtures were pretested in laboratory to achieve the compressive strength more than 28 MPa at 28 days while provided at least 10 cm slump after pouring 2 hours. The mix required 4.5 tons of NaOH 6M and 1.7 tons of sodium silicate to be prepared and stocked in the existing OPC ready mixed plant. These two chemicals had to be well mixed in activator tank to reduce the temperature then rise to ambient before discharging to the batch Please click Additional Files below to see the full abstract

Success story of alkali-activated high calcium oxide fly ash concrete handling for cast in-situ road construction

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อิทธิพลของระบบโครงอาคารต่อค่าสัมประสิทธิ์แรงเฉือนที่ฐานอาคารสูงไม่เกิน 23 เมตร ในประเทศไทย

This research had the objectives to inspect the suitable structural systems and to find the seismic base shear of the buildings lower than 23 meters in each area in Thailand. The method used in this research was static method issued by Department of Public Works and Town & Country Planning (DPT 1302): The Equivalent Static Force Method. The building type was general building with normal importance class. After that, the software DON_V1 was used to analyze for finding the seismic response coefficient (CS ) and the seismic base shear (V ) of all 7 structure systems specified in DTP 1302 of the country data. Then the calculated seismic response coefficient of each system were compared, making the designer be able to choose the well-suitable structure in each area of Thailand. The research result found important data, i.e. at the Mae Chan District, Chiangrai Province, the ductile/special reinforced concrete moment resisting frame CS was 0.087 whereas the ordinary reinforced concrete moment resisting frame could not be used in the design. Moreover, CS of the ductile/reinforced concrete moment resisting frame, in the same building type but in the other areas, were many times different, such as in Phu Pha Man District, Khon Kaen Province, the CS of the ductile/reinforced concrete moment resisting frame was equal to 0.108, less than in Mae Chan District, Chiangrai Province, 4.8 times

Development application on tablet for increase construction inspection efficiency

AbstractThis research aims to develop application for increase the construction inspection efficiency and evaluate theperformance by the construction inspector who has been using and not using this tool. The tool was created to divide the work into two parts: the web site and a portable computer (Tablet). The user can monitor the construction work in Web site. This tool can record comments about the shortcomings and improvement in the construction work in each period. Content in this tool used principles of construction inspection of the Engineering Institute of Thailand (EIT), which was used as the reference. This tool are created and developed by the specialist in the field of construction and information technology. The next step to evaluate performance in the construction inspection by 30 users who was the construction inspectors in type of reinforced concrete buildings projects. The topics of performance are five terms which were to evaluate the effectiveness of each side. The results showed that score highest in terms of performance, convenience andcoordination of the construction. And terms second is ability to increase knowledge and understanding, confidence andtransparency construction inspectors. Which shows that this tool makes the job particularly those who have no knowledge of terms construction work is to understand more in construction. It also makes it more transparent in the work with And also makes it easy to work even more

Effect of nanosilica-based activators on the performance of an alkali-activated fly ash

This paper assesses the effect of the use of an alternative activator based on nanosilica/MOH (M = K+ or Na+) blended solutions on the performance of alkali-activated fly ash binders. Binders produced with commercial silicate activators display a greater degree of reaction, associated with increased contents of geopolymer gel; however, mortars produced with the alternative nanosilica-based activators exhibited lower water demand and reduced permeability, independent of the alkali cation used. Na-based activators promote higher compressive strength compared with K-based activators, along with a refined pore structure, although K-activated samples exhibit reduced water demand. Zeolite type products are the major crystalline phases formed within these binders. A wider range of zeolites is formed when using commercial silicate solutions compared with the alternative activators. These results suggest that there are variations in the availability of Si in the system, and consequently in the alkalinity, depending on the silicate source in the activator, which is important in determining the nanostructure of the geopolymer gel.This study was sponsored by the Ministerio de Ciencia e Innovacion of Spain (Project GEORES MAT2010-19934 and research scholarship BES-2008-002440), European regional development fund (FEDER), and the Universitat Politecnica de Valencia (Spain). The participation of SAB and JLP was funded by the Australian Research Council (ARC), including partial funding through the Particulate Fluids Processing Centre, a Special Research Centre of the ARC. A special acknowledgement is also due to the Centre of Electron Microscopy of the Universitat Politecnica de Valencia and Pedro Garces from the Universidad de Alicante for support in some experiments.Rodriguez Martinez, ED.; Bernal, SA.; Provis, JL.; Paya Bernabeu, JJ.; Monzó Balbuena, JM.; Borrachero Rosado, MV. (2013). Effect of nanosilica-based activators on the performance of an alkali-activated fly ash. Cement and Concrete Composites. 35(1):1-11. doi:10.1016/j.cemconcomp.2012.08.025S11135

The influence of rice husk ash addition on the properties of metakaolin-based geopolymers

This paper investigates the replacement of metakaolin (MK) with rice husk ash (RHA) in the production of alkali-activated binders or geopolymers. The influence of the RHA addition on compressive and flexural strength, as well as water absorption and apparent porosity were determined, in terms of the percentage of RHA in the mixture and molar ratios of the mixes. Fourier Transform Infrared (FTIR) spectroscopy and Energy Dispersive spectroscopy (EDS) were carried out to assess the changes in the microstructure of the geopolymer matrices with the RHA addition. Results have shown that RHA may be a supplementary precursor for geopolymers. The composition of the geopolymer matrices containing 0-40% RHA is very similar, which indicates that the additional Si provided by RHA is not incorporated to the geopolymer matrix. In addition, geopolymers with RHA content higher than 40% present a plastic behavior, characterized by extremely low strength and high deformation, which can be attributed to the formation of silica gel in formulations containing variable Si/Al ratio

Evaluation of Strengths from Cement Hydration and Slag Reaction of Mortars Containing High Volume of Ground River Sand and GGBF Slag

This paper investigates the cement hydration, and the slag reaction contributes to the compressive strengths of mortars mixed with ground river sand (GRS) and ground-granulated blast furnace (GGBF) slag with different particle sizes. GRS (inert material) and GGBF slag (reactive material) were ground separately until the median particle sizes of 32 ± 1, 18 ± 1, and 5 ± 1 micron and used to replace Portland cement (PC) in large amount (40–60%) by weight of the binder. The results showed that, at the early age, the compressive strength obtained from the cement hydration was higher than that obtained from the slag reaction. The results of compressive strength also indicated that the GGBF slag content and particle size play important roles in the slag reaction at the later ages, whereas cement hydration is more prominent at the early ages. Although the results could be expected from the use of GGBF slag to replace PC in mortar or concrete, this study had presented the values of the compressive strength along with ages and the finenesses of GGBF slag that contributed from cement hydration and from GGBF slag reaction