In this study, bearing capacities under large lateral displacement were obtained using the formulas suggested by Naeim & Kelly(1999) and ISO 22762 Part.3(2010) and those were compared with the results of Hwang's experiments(2006) to decide which formula is more reasonable
For coupled shear walls, coupling beams are the first line of dissipation under earthquakes. So coupling beams are important energy dissipation component. When coupling beams have little depth-to-span ratio, routine coupling beams have less capacity of energy dissipation.There are less design methods for coupling beams with depth-to-span less than 2. In this paper a specimen with steel plate reinforcement coupling beam was designed and analyzed by means of FEM software ABAQUS.
This research is a part of a research program to verify the seismic performance of circular reinforced concrete bridge columns with respect to longitudinal steel ratio and transverse steel ratio under cyclic lateral load. In this paper, describes mainly displacement ductility of circular reinforced concrete bridge columns with respect to test variables.
This study revealed that seismic retrofit technology which has to conduct seismic retrofit work after removing facing walls from a reinforced concrete structured building constructed with masonry walls and facing walls, bears disadvantages of additional costs both for removal of facing walls and for brick masonry and possibility to incur the secondary damage from collapse of facing walls. Therefore, this study aims to develop a seismic retrofit technique and examines its performance which can yield sufficient seismic retrofit effect without additional retrofit of facing walls by forming a pile-bent reinforced concrete walls with facing walls after removing masonry walls.
This research is a part of a research program to verify the seismic performance of reinforced concrete bridge columns of octagonal cross-section under cyclic lateral load. In this paper, describes mainly failure behavior of octagonal reinforced concrete bridge columns.
This paper presents analytical studies on the cyclic behavior of column-tree steel moment connections by FEA. The column-tree moment connections are composed shop welded beam-to-column connection and field bolted beam-to-beam splice. Two analytical model of column-tree moment connections were designed with beam splice lengths of 900mm and 1,100mm, which are roughly 1/6 and 1/7 of the span length of 7,500mm. In order to verify the FEA reliability, the analytical results was compared with experimental results. Meanwhile, the experimental results were understood better through analysis procedure.
In order to reduce the carbon dioxide exhaust quantity and the energy amount and the waste which becomes the global warming primary reason recently, the most efficient method was focused on the long-life building in Structural field. So in order to improve seismic capacity, new shape steel damper may be used in bolted connection, which made reuse of member impossible owing to serious brittle fracture of main member such as beam and column. To solve above problem, new type connection was developed and tested. As result of test, new type connection was shown good seismic capacity and main member such as beam and column were stable behavior.
In this study, experimental research was carried out to evaluate and improve the constructability and structural performance of high strength R/C interior beam-column joints regions, with or without the shear reinforcement, using high ductile fiber-reinforced mortar. Specimens designed by retrofitting the interior beam-column joint regions of existing reinforced concrete building showed a stable mode of failure and an increase in load-carrying capacity due to the effect of enhancing dispersion of crack control at the time of initial loading and bridging of fiber from retrofitting new high ductile materials during testing.
In this study, shear assessment equation of reinforced concrete interior beam-column joints without shear reinforcement using high ductile fiber reinforced mortar based on the test results was proposed. Suggested equation was proposed to modify Hegger's seismic design equation. It was reflected the effect of high ductile fiber incorporated
This study is to update of vibration power generating model and to analyze electromotive force on subway. Analysis of electromotive force using power generation depending on classification of locations which are ballast bed and concrete bed. Induced electromotive force equation by Faraday's law was updated using Bayesian regression and correlation analysis with calculate value and experiment value. Using the updated model, it could get 40mV per one power generation in ballast bed, and it also could get 4mV per one power generation in concrete bed.
As international regulations for greenhouse gas emissions is strengthened in order to respond to climate change all over the world, we need to reduce greenhouse gas in urban planning. we derived the elements of the plan for a carbon balance of Seoul and suggested a methodology of urban design guidelines regarding the carbon balance.
In this paper, heating and cooling system propose to the smart green tunnel which is reduction of green house gas. Ground temperature calculated to planning the installation of underground heat exchanger at the bottom of the tunnel, It drew a deduction of the economic saving as calculating amount of existing fuel reduction and amount of heat through heating and cooling system
In this paper, we evaluate the applicability of p-y curve on the lateral behavior of monopile foundations as compared with FEM 3D models and present safety factors in case p-y curve method is used to investigate the lateral behavior of monopile foundations for 5MW offshore wind turbines in Korea.
The schedule speed is one of the most important elements of railway industry. In korea, Gyeongbu Line’s highest speed is 300km/h. But it’s schedule-speed is no more than about 174km/h from Seoul to Busan. In this study, we analyzed the effect of the proposed improvements in the speed reduction zone using Train Performance Simulation. We found that the improvements can raise the schedule speed from 15 to 20%.
For pile construction of underground extension in the remodeling, existing piling method have limitations. These method can't access the restricted area and construction period must be delayed by many piling steps. To overcome these defects of existing method, SAP method is developed and gained the NET(No.684). Also, SAP method applied in remodeling site of Chung-Dam Dong 00 APT.
On this study, We make an active MgO and Mg-Si material as a main material using autoclave and electric furnace. Mineral admixtures are added to main material, and to enhance the activity of carbon negative cement, MgCl2 solution is mixed to the paste and concrete. To evaluate the activity of hydration, mechanical property, autoclave expansion, hydrate property, SEM, freezing and thawing test of concrete are analyzed
The purpose of this study is to assess and analyse the environmental impact of construction stage by apartment houses structure using main materials. For this purpose, according to the structure of the apartment houses, by setting the evaluation model and using 6 kinds of main materials, the environmental assessment about 6 environmental category was performed
To evaluate the crack resistance of steel fiber reinforced concrete, which has use the restrained shrinkage crack test method , performance test is conducted with the variables of Steel fiber.
The energy consumption by buildings approximately reaches 25% of total korea energy consumption. The greatest part in the buildings of the energy consumption is building facade. but a few research projects on concrete comprising more than 70% of outsider of buildings has been tried. This research structural insulation concrete what improved insulation performance using insulation performance improve material
When manufacturing secondary concrete products, steam and autoclave curing are practiced for the purpose of securing product performance at early phase. CO2 is generated by combustion of fossil fuel at the time of curing. This study is part of a research conducted to minimize curing process which generates CO2. Combination materials types, substitution ratio, strength property per different types of curing are compared and evaluated. Result of the experiment indicates that combination material with 40% blast furnace slag substitution and W/B which has gone through 30,40% steam curing are the most outstanding experiment bodies.