• Journal of Welding and Joining
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• v.12 no.4
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• pp.151-161
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• 1994

FCAW has wide application in ship fabrication, maintenance and field erection. It has many advantages over SMAW.SAW and GMAW process. In many applications, the FCAW provides highquality weld metal. This method can reduce weld defects especially porosity and spatter. But the fatigue characteristics of those deposited metal have been rarely investigated. The purpose of this study is to investigate the cyclic stress-strain behavior and fatigue tests by the constant strain control were carried out on the rounded smooth specimen with deposited metal using the metal type flux cored wire. As the results of this study for the deposited metal welded by the metal type flux cored wire, the hardening or softening characteristics under cyclic load were investigated and cyclic stress-strain curve, strain-fatigue life curve, stress-strain function and fatigue life relation which are useful to estimate the fatigue life under the stress concentration condition were obtained.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1996.04a
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• pp.202-211
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• 1996

A number of typical type of steel-box pedestrian bridges are constructed in the metropolitan highway or heavy traffic urban area. Although it has the advantage of speedy construction because of its simple structural form and prefabricated erection method, it has been reported that many of these bridges are deteriorated or damaged and thus are in the state such that it would give unsafe and uncomfortable feeling to pedestrians. In the paper, for the realistic assessment of safety and residual earring-capacity of deteriorated and/or damaged steel box pedestrian bridges, an interactive non-linear limit state model are formulated based on the von Mises' combined stress yield criterion. It is demonstrated that the proposal model is effective for the reliability-based safety assessment and residual carrying-capacity evaluation of steel-box pedestrian bridges. In addition, this study suggests an effective and practical field load test method for pedestrian bridges.

• Journal of the Korea Institute of Building Construction
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• v.9 no.3
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• pp.51-58
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• 2009

The intention of this study is to analyze safety consciousness of construction labors in Gawang-Ju region. According to Korea Occupational Safety & Health Agency, the rate of disaster in construction industry is very high comparing with other fields. Most of all, the consciousness of construction labors is very important because accidents are caused from it mainly. For this reason, it is necessary to recognize safety consciousness of labors who directly work in construction field. For decreasing the rate of disaster in construction, I examined and analyzed safety consciousness of construction labors and then, groped improvement of safety activity. Finally, this study deducted improvement of safety activities and management.

• Wind and Structures
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• v.1 no.1
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• pp.67-75
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• 1998

Tiger Gate Bridge, a steel suspension bridge with a main span of 888 m and a stiffening box girder, is located at the Pearl River Estuary, Guangdong Province, one of the typhoon-prone area in China. Focusing on the developing of the full aeroelastic model of the bridge and simulation of the wind field of the bridge site in a large boundary wind tunnel at Tongji University, Shanghai, China, some main results about the wind resistant properties of the bridge including aerodynamic instability, buffeting responses both being in operation and erection stages by using of a full aeroelastic model wind tunnel testing are introduced. Some of analytical approaches to those aerodynamic behaviours are also presented, and compared with experimental data of the testing.

• Advances in concrete construction
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• v.3 no.4
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• pp.295-316
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• 2015

A bridge widening technology using steel-concrete composite system was developed and is presented in this paper. The widened superstructure system consists of a newly built composite steel-concrete girder with concrete deck and steel diaphragms attached to the existing concrete girders. This method has been applied in several bridge widening projects in China, and one of those projects is presented in detail. Due to the higher stiffness-to-weight ratio and the rapid erection of composite girders, this widening method reveals benefits in both mechanical performance and construction. As only a few methods for the design of bridges with different types of girders are recommended in current design codes, a more accurate analytical method of estimating live load distribution on girder bridges was developed. In the analytical model, the effects of span length, girder pacing, diaphragms, concrete decks were considered, as well as the torsional and flexural stiffness of both composite box girders and concrete T girders. The study shows that the AASHTO LRFD specification procedures and the analytical models proposed in this paper closely approximate the live load distribution factors determined by finite element analysis. A parametric study was also conducted using the finite element method to evaluate the potential load carrying capacities of the existing concrete girders after widening.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.139-142
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• 2009

The worldwide energy market is enlarging rapidly according to current issues like globalization, deregulation, global warming and strengthening for environmental regulation as well as the energy technology is developing speedily by the add of information and communication techniques. In spite of these advanced techniques in the field of the renewable energy, solar power depends on the governmental aid largely in comparison with other renewable energy sources because of the high initial investment cost. Therefore it is important to investigate scrupulously for the expected erection site of solar power plant from the planning stage. This paper shows actual measurement data of solar radiation of scheduled solar power locations in the waterworks site with consideration of waterworks facilities and regional specialties and presents the data which was analyzed comparably with the radiation data of adjacent locations served by national authorities. In addition, these data were analyzed using RETScreen and used for making decision on the business validity.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10b
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• pp.995-1000
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• 2000

Segmentally erected prestressed concrete box girder bridges have been widely used in Korean high speed railway. Segmental erection has been accomplished along the longitudinal direction and across the depth of cross section. The cross section is similar to a composite cross section, composed of old and new segments. Because these segments have different time-dependent creep and shrinkage properties, a stress redistribution takes place during the construction period. It is the main objective in this research to investigate this behavior. An actual bridge was instrumented with 96 vibrating wire embedded type strain gauges, 6 electronic type steel strain gauges, and 75 thermocouples. Two span continuous high speed railway bridge was selected. Two points of importance, such as the midpoint of the first span and the point of interior support, along the span of the girder were chosen to monitor the time dependent behaviors for an extended period of time. The data collection was starting just after concrete girder were cast and is still going on. According to the measured results, the strain distributions across the depth of the section at midspan and interior support were not continuous and the important redistribution of stresses takes place. Thus, rational design of prestressed concrete composite box girder bridges need.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.265-268
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• 2008

In this paper behavior of U-Channel Bridge (UCB) and the slab design considering construction sequence was studied. The segments of UCB are produced in the factory and transported to the site by trailers, and the segments are fabricated in the construction field. In this sequence the supporting conditions are changed. Four steps that were the segment precasting step, the segment carrying step, the segment placed on the erection beam step, and the completion step were chosen by supporting condition. In each step model using the frame and plate elements was proposed and structural analysis was performed. Four construction steps were to be considered in the process of slab analysis. The design method of slab was proposed considering construction sequence.

• Journal of Ocean Engineering and Technology
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• v.26 no.5
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• pp.18-24
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• 2012

This paper concerned with the behaviour of shaping formation and the erection for SCST structure by cable-tensioning for three kinds of structure models. The joint types of experimental models are ball type joints, bolt type joints with gusset plates, and bolt type joints. The feasibility of the proposed shaping method and the reliability of the established geometric model were confirmed with a nonlinear finite element analysis and an experimental investigation for full size scaled pyramid test model and three kinds of SCST structure models. The characteristic of the behaviour of each joint type is shown in the shaping test for practical design purposes. As a results, the behaviour characteristics of joints is very significant in shaping analysis of space structures. So the joint type should be considered in the design and analysis of the shape formation for space structures. Also, in the special field condition, it could be a fast and economical method for constructing the space structure.

• Journal of architectural history
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• v.8 no.3 s.20
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• pp.9-22
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• 1999

The purpose of this study is to analyse the architectural character of JE-DAMG at farm village in Ulsan. JE-DANG means the building for DONG-JE (the sacrificial rite of a village). The regions of this study are KANG-DONG MYEN, and UNG-CHON MYEN in Ulsan. The method of this study is the analysis of them after the actual field surveys of 47 JE-DANGs in these regions The survey contains the area, the height, the period of the erection, the architectural structure, the roof shape, the material, the landowner, SHIN-CHE (means a god's name and shape), DANG-SU tree and so on. Methods of the survey are the field survey, the interview of villager, the analysis of reference data and so on. Results of the study are below. JE-DANGs(buildings) of these regions had been built first in the period of Japanese occupancy and erections of them had continued until 1970's. Since then, they have been rebuilt. The primary JE-DANG is characterized by a tiled roof, a wooden post lintel, a mud-plastered wall, and a wooden door. After rebuilding, characters are a flat slab, a tiled roof, a structure of using red bricks, and the area is getting larger than the primary JE-DANG, but 1 KAN persists without variety. Most of houses in the inland area like UNG-CHON MYEN face the south, and ones in the coastal area like KANG-BONG MYEN face the east. Generally there is DANG-SU tree behind JE-DANG. That proves DANG-SU tree to be the object of the rite. The species of DANG-SU is a pine in general ,but various in UNG-CHON MYEN. In general names of the god are DONG-SHIN , DANG-SAN SHIN and SUNG-HWANG SHIN. I think that the landownership of JE-DANG should change the private ownership into the village ownership to preserve JE-DANG though most of lands of JE-DANG are private ones.