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Ready-mix concrete is not always affordable because it is less economical for small projects. This study shows an effort to introduce alternative home-produced concrete for small paving areas such as sidewalks, backyards, or fixing the existing concrete and discusses the economic evaluation of the alternative concrete for home purpose. The materials being used in this study are available locally or are easily purchased. The primary objective of the study is to analyze the compressive strength and conduct economic analysis of alternative home-produced concrete with different mix designs. Wood ash, fly ash, and recycled aggregate concretes are the alternative concrete types discussed in this study. Fly ash can replace Portland cement up to 30% without losing significant compressive strength of the concrete. Furthermore, fly ash is less expensive than Portland cement and can reduce the cost of concrete by saving approximately 15%. Wood ash can be used up to 25% in concrete without losing considerable strength which saves approximately 13% of cement cost. The use of recycled concrete aggregates saves only about 1% CO2 emission compared to regular concrete while fly ash saves more than 28.5% and wood ash saves almost 24.5%. They can replace natural aggregates up to 100%, but there is only a 5% saving. In addition, an equivalent cost of USD 13.47 for one cubic yard of concrete could be saved by using 30% fly ash concrete when considering reduced emitted CO2eq from the material production.
Muhammad Shaker; Mayurkumar Bhalala; Qayoum Kargar; Byungik Chang. Evaluation of Alternative Home-Produced Concrete Strength with Economic Analysis. Sustainability 2020, 12, 6746 .
AMA StyleMuhammad Shaker, Mayurkumar Bhalala, Qayoum Kargar, Byungik Chang. Evaluation of Alternative Home-Produced Concrete Strength with Economic Analysis. Sustainability. 2020; 12 (17):6746.
Chicago/Turabian StyleMuhammad Shaker; Mayurkumar Bhalala; Qayoum Kargar; Byungik Chang. 2020. "Evaluation of Alternative Home-Produced Concrete Strength with Economic Analysis." Sustainability 12, no. 17: 6746.
High mast light poles (HMLP) are used nationwide on major interstates and at local intersections for luminary purposes in the United States. The HMLPs are subjected to major oscillatory wind loading which may cause fatigue and earlier life expediency failure. From the concerns that HMLP failures would lead to pedestrian harm, extensive studies were performed to develop a standard model of behavior for high wind loads and vortex shedding that can be used for future design. Numerical modeling with the use of Computational Fluid Dynamics (CFD) is proposed to simulate the typical shape (dodecagonal cylinders) of the HMLPs and be validated with wind tunnel experiments. The k-ω based SAS-SST turbulence model will be used to handle the turbulence closure for the fully turbulent flow regime. The work done will look at validating static and dynamic force coefficients of a dodecagonal cylinder at different orientations. In addition, the lock-in behavior will be simulated to determine the applicability of modern CFD approaches to be able to perform the oscillatory behavior of a dodecagonal cylinder. Added mass cases also will be examined to determine the damping effects on an unsteady cylinder as additional in-depth study.
Christopher Ong; Byungik Chang; Maria-Isabel Carnasciali; Ravi Gorthala. Development of CFD-based aerodynamic parameters for a multi-sided cylinder. Journal of Wind Engineering and Industrial Aerodynamics 2020, 199, 104130 .
AMA StyleChristopher Ong, Byungik Chang, Maria-Isabel Carnasciali, Ravi Gorthala. Development of CFD-based aerodynamic parameters for a multi-sided cylinder. Journal of Wind Engineering and Industrial Aerodynamics. 2020; 199 ():104130.
Chicago/Turabian StyleChristopher Ong; Byungik Chang; Maria-Isabel Carnasciali; Ravi Gorthala. 2020. "Development of CFD-based aerodynamic parameters for a multi-sided cylinder." Journal of Wind Engineering and Industrial Aerodynamics 199, no. : 104130.
The primary objective of the project is to evaluate the benefits of wind and solar energy and determine economical investment sites for wind and solar energy in Texas with economic parameters including payback periods. A 50 kW wind turbine system and a 42 kW PV system were used to collect field data. Data analysis enabled yearly energy production and payback period of the two systems. The average payback period of a solar PV system was found to be within a range of 2–20 years because the large range of the payback period for PV systems were heavily influenced by incentives. This is in contrast to wind energy, where the most important factor was found to be wind resources of a region. Payback period for the installed wind system in Texas with federal tax credits was determined to be approximately 13 years.
Byungik Chang; Ken Starcher. Evaluation of wind and solar energy investments in Texas. Renewable Energy 2018, 132, 1348 -1359.
AMA StyleByungik Chang, Ken Starcher. Evaluation of wind and solar energy investments in Texas. Renewable Energy. 2018; 132 ():1348-1359.
Chicago/Turabian StyleByungik Chang; Ken Starcher. 2018. "Evaluation of wind and solar energy investments in Texas." Renewable Energy 132, no. : 1348-1359.