• Advances in Computational Design
• /
• v.2 no.4
• /
• pp.273-281
• /
• 2017

In this work, a comparative study of multi-objective meta-heuristics (MOMHs) for optimum design of a walking tractor handlebar is conducted in order to reduce the structural mass and increase structural static and dynamic stiffness. The design problem has objective functions as maximising structural natural frequencies, minimising structural mass, bending deflection and torsional deflection with stress constraints. The problem is classified as a many-objective optimisation since there are more than three objectives. Design variables are structural shape and size. Several well established multi-objective optimisers are employed to solve the proposed many-objective optimisation problems of the walking tractor handlebar. The results are compared whereas optimum design solutions of the walking tractor handlebar are illustrated.

• Structural Engineering and Mechanics
• /
• v.52 no.5
• /
• pp.857-873
• /
• 2014

Structural behaviors of a sustainable hybrid column with the ultra high performance cementitious composites (UHPCC) permanent form under compression and flexure were studied. Critical state and failure stage characters are analyzed for large and small eccentricity cases. A simplified theoretical model is proposed for engineering designs and unified formulas for loading capacity of the hybrid column under compression and flexure loads are derived, including axial force and moment. Non-linear numerical analysis is carried out to verify the theoretical predictions. The theoretical predictions agree well with the numerical results which are verified by the short hybrid column tests recursively. Compared with the traditional reinforced concrete (RC) column, the loading capacity of the sustainable hybrid column is improved significantly due to UHPCC confinements.

• International conference on construction engineering and project management
• /
• 2007.03a
• /
• pp.366-375
• /
• 2007

Our nation has a problem with discrimination of income distribution and inefficient of resources distribution caused by real estate price rising from a sudden economy growth and industrialization. Specially, in recent years, there is a great disparity of condominium price between the north and south of the Han river. Because the housing price is deciede by the immanent value of a house and neighborhood effects of the regional where the house is situated, the housing price is occurred difference. In this study, I analyzed the differences of housing price determinants about condominium developments in the old and new residential areas, and found the important factors that affect the condominium price using Structural Equation Modeling(SEM) The purpose of study is to analyze the influence of various factors of housing price. Also, this study tried to predict real estate market and to establish previous effective real estate policy.

• Journal of Korean Society of Steel Construction
• /
• v.25 no.5
• /
• pp.509-518
• /
• 2013

This study is aimed at developing of the sustainable interface module for structural design. It is dealt with the Midas/Gen for analysis and design and Tekla Structures for Building Information Modeling. In this research, it is improved the applicability and function of the existing interface module developed by authors. Although model information was functionally well linked by the existing module in both directions, the applicability is limited due to the difference of attributes between structural analysis model and structural detail model. In this study, we analyzed the problems that occur in existing module. We have developed the interface module to solve the problems and improved the applicability of the existing module.

• Earthquakes and Structures
• /
• v.3 no.6
• /
• pp.783-804
• /
• 2012

Because of its large contribution to the environmental instability of the planet, the building industry will soon be subjected to a worldwide scrutiny. As a consequence, all professionals involved in the building industry will need to create a professional media in which their daily work adequately solves the technical issues involved in the conception, design and construction of concrete and steel buildings, and simultaneously convey care for the environment. This paper discusses, from the point of view of a structural engineer involved in earthquake-resistant design, some of the measures that can be taken to promote the consolidation of a building industry that is capable of actively contributing to the sustainable development of the world.

• Earthquakes and Structures
• /
• v.9 no.6
• /
• pp.1337-1353
• /
• 2015

Seismic upgrading of existing structures is a technical and social issue aimed at risk reduction. Sustainable design is one of the most important challenges in any structural project. Nowadays, many retrofit strategies are feasible and several traditional and innovative options are available to engineers. Basically, the design strategy can lead to increase structural ductility, strength, or both of them, but also stiffness regulation and supplemental damping are possible strategies to reduce seismic vulnerability. Each design solution has different technical and economical performances. In this paper, four different design solutions are presented for the retrofit of an existing RC frame with poor concrete quality and inadequate reinforcement detailing. The considered solutions are based on FRP wrapping of the existing structural elements or alternatively on new RC shear walls introduction. This paper shows the comparison among the considered design strategies in order to select the suitable solution, which reaches the compromise between the obtained safety level and costs during the life-cycle of the building. Each solution is worked out by considering three different levels of seismic demand. The structural capacity of the considered retrofit solutions is assessed with nonlinear static analysis and the seismic performance is evaluated with the capacity spectrum method.

• Structural Engineering and Mechanics
• /
• v.82 no.2
• /
• pp.133-149
• /
• 2022

This study investigates the resistance of sustainable ultra-high performance concrete (UHPC) on steel reinforcement corrosion. For enhancing the sustainability of UHPC, concrete mixes were prepared with ordinary Portland cement main binder, and mixes with moderate to high percentages of blast furnace cement (CEM III), fly ash (FA), and slag cement as partial replacements of the full quantity of the used cement. Linear polarization resistance technique was employed to estimate the electrochemical behavior of the concrete specimens. Results showed that the compressive strength and the resistance of steel to corrosion in marine environments can be enhanced by improving the sustainability of UHPC through incorporation of CEM III, FA, and slag cement. FA replacement of up to 50% with the addition of 15% SF content produced better compressive strength and steel corrosion resistance than slag cement whether with the use of ordinary Portland cement or blast furnace cement as the main binder.

• Smart Structures and Systems
• /
• v.16 no.3
• /
• pp.521-535
• /
• 2015

Vibration-based monitoring is one approach used to perform structural condition assessment. By measuring structural response, such as displacement, dynamic characteristics of a structure may be estimated. Often, the primary dynamic responses in civil structures are below 5 Hz, making accurate low frequency measurement critical for successful dynamic characterization. In addition, static deflection measurements are useful for structural capacity and load rating assessments. This paper presents a DC coupled continuous wave radar to accurately detect both dynamic and static displacement. This low-cost radar sensor provides displacement measurements within a compact, wireless unit appropriate for a range of structural monitoring applications. The hardware components and operating mechanism of the radar are introduced and a series of laboratory experiments are presented to assess the performance characteristics of the radar. The laboratory and field experiments investigate the effect of factors such as target distance, motion amplitude, and motion frequency on the radar's measurement accuracy. The results demonstrate that the radar is capable of both static and dynamic displacement measurements with sub-millimeter accuracy, making it a promising technology for structural health monitoring.

• Structural Engineering and Mechanics
• /
• v.86 no.5
• /
• pp.687-704
• /
• 2023

This study aims to examine the structural response of glass fibre-reinforced polymer (Glass-FRP) reinforced geopolymer electronic waste aggregate concrete (GEWC) compression elements under axial compression for sustainable development. The research includes the fabrication of nine GEWC circular compression elements with different reinforcement ratios and a 3-D nonlinear finite element model using ABAQUS. The study involves a detailed parametric analysis to examine the impact of various parameters on the behavior of GEWC compression elements. The results indicate that reducing the vertical distance of glass-FRP ties improves the ductility of GEWC compression elements, and those with eight longitudinal rebars have higher axial load-carrying capacities. The finite element predictions were in good agreement with the testing results, and the put forwarded empirical model shows higher accuracy than previous models by involving the confinement effect of lateral glass-FRP ties on the axial strength of GEWC compression elements. This research work contributes to minimizing the carbon footprint of cement manufacturing and electronic waste materials for sustainable development.

• International conference on construction engineering and project management
• /
• 2009.05a
• /
• pp.573-578
• /
• 2009

Previous research on super high rise buildings focused mostly on the use of public space from building plan perspective, survey of residents' satisfaction evaluation, construction technology and structural technology. But little research is done on the economic analysis of landmark factors. The purpose of this study is to find landmark factors that can be quantitatively measured, collect data on super high rise residential buildings in Seoul. Find the intrinsic values of the landmarks, and analyze how these values differ in areas with different densities, i.e. in 3 Gangnam-gus & Yeongdeungpo-gu and in other areas. It is expected that the results of this study can be used to set an appropriate price of super high rise building in consideration of its landmark value in different area