• Title/Summary/Keyword: Steel construction

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Corrosion and Abrasion Characteristics of PE Sheet Laminated Corrugated Steel Pipe (PE 선피복 파형강관의 부식 및 마모 특성)

  • Kim, Seog-ku;Jeong, Jang-sik;Kwak, Phill-jae;Choi, Jun-hyang;Lee, Hyun-dong;Lee, Tae-yoon
    • Journal of Korean Society on Water Environment
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    • v.20 no.2
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    • pp.163-169
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    • 2004
  • Feasibility of using PE sheet laminated CSP(Corrugated steel pipe) to sewers were tested via corrosion and abrasion tests for PE sheet laminated CSP; 1) corrosion test for PE film and PE coated plate, 2) corrosion test for joint of PE sheet laminated CSP, 3) corrosion test for outside of PE sheet laminated CSP, and 4) abrasion test for inside of PE sheet laminated CSP. The results for the corrosion and abrasion tests are as follows. 1. Results for corrosion tests on PE films and zinc coated steel plates that were coated with PE films show that the surfaces of both PE were not changed compared to those of original PE samples. Furthermore, PE films maintained strong adhesion on the steel plates even though they were exposed to sewage and seawater provided cutting planes of the steel plates were treated with molding. But, results for corrosion tests on the spots that were previously cut off by a knife and a cutting planes of the steel plates were treated without molding show that steel plates have been corroded if they were exposed to sewage and seawater. 2. Results for corrosion tests on joints of PE sheet laminated corrugated steel using sewage show that gathering rust was observed at cutting plane of PE sheet laminated corrugated steel after 180 days, but PE film was not flaked off. However, PE film at cutting plane was flaked off when PE sheet laminated corrugated steel was exposed to seawater. Furthermore, flaking process was severely progressed at lockseam points of which the surfaces were not smooth. 3. Results for laying PE sheet laminated corrugated steel under the ground show that the surface of untouched PE film was almost identical to that of original PE film. However, the spots that were previously cut off by a knife and a cutting plane of PE sheet laminated corrugated steel have flaked off. 4. As a result of abrasion tests conducted with PE sheet laminated corrugated steel and sand, brilliance and thickness of PE was not greatly changed under the severe abrasion conditions. Therefore, the durability of PE sheet laminated corrugated steel for abrasion was determined to be good.

Experimental and analytical performance evaluation of steel beam to concrete-encased composite column with unsymmetrical steel section joints

  • Xiao, Yunfeng;Zeng, Lei;Cui, Zhenkun;Jin, Siqian;Chen, Yiguang
    • Steel and Composite Structures
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    • v.23 no.1
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    • pp.17-29
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    • 2017
  • The seismic performance of steel beam to concrete-encased composite column with unsymmetrical steel section joints is investigated and reported within this paper. Experimental and analytical evaluation were conducted on a total of 8 specimens with T-shaped and L-shaped steel section under lateral cyclic loading and axial compression. The test parameters included concrete strength, stirrup ratio and axial compression ratio. The response of the specimens was presented in terms of their hysterisis loop behavior, stress distribution, joint shear strength, and performance degradation. The experiment indicated good structural behavior and good seismic performance. In addition, a three-dimensional nonlinear finite-element analysis simulating was conducted to simulate their seismic behaviors. The finite-element analysis incorporated both bond-slip relationship and crack interface interaction between steel and concrete. The results were also compared with the test data, and the analytical prediction of joint shear strength was satisfactory for both joints with T-shaped and L-shaped steel section columns. The steel beam to concrete-encased composite column with unsymmetrical steel section joints can develop stable hysteretic response and large energy absorption capacity by providing enough stirrups and decreased spacing of transverse ties in column.

Safety Assessment to Construction Position of Constructed Steel Structures under Declinating Earth Pressure (편토압을 받는 파형강판 구조물의 시공위치별 안전성 평가)

  • Lee, Sang-Hyun;Lim, Heui-Dae
    • Journal of the Korean Society of Safety
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    • v.23 no.1
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    • pp.28-34
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    • 2008
  • The corrugated steel plate structures is applied to the construction of mountain tunnel portal part with shallow depth, the tunnel on the outskirts of urban areas and ecology move passage. In this study, A finite element method is used for research the behavior of corrugated steel plate structures due to construction position under declinating earth pressure and excavation depth. A finite element method were performed varying construction position(10, 15, 20 and 25m) from slope and excavation depth from surface. The hoop thrust and moment, displacement of corrugated steel plate subjected to construction position and excavation depth is determined from a finite element method. From results of finite element method, it was found that the increase of thrust and the decrease of displacement as the amount of distance increase from slope with construction position. But the thrust and moment, displacement has not different value with excavation depth.

Frequency variation in construction stages and model validation for steel buildings

  • Aras, Fuat
    • Steel and Composite Structures
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    • v.22 no.3
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    • pp.647-662
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    • 2016
  • This study aims to monitor the variation of modal frequencies of steel buildings during their construction sequence. In this respect, construction of a steel building is followed by vibration based measurements. The monitored building is a three-story educational building within a building group whose structural system consists of steel moment resisting steel frames and eccentric braces. Five different acceleration measurements in two perpendicular directions are taken on five different construction stages, starting from the erection of the columns and beams ending with the completion of the construction. The recorded measurements are transferred into frequency domain and the dominant frequencies for each case have been determined. The change in the dominant frequencies is evaluated with the existing construction stages and performed constructional works between the stages. The last measurement, performed on the building in service, revealed the first two dominant frequencies as mutual in X and Y direction, showing that these dynamic modes are torsional modes. This result is investigated by numerical analysis performed with finite element model of the building constructed for design purpose. Lower frequencies and different mode shapes are determined from numerical analysis. The reason of lower frequencies is discussed and the vibration survey is extended to determine the effects of an adjacent building. The results showed that the building is in strong relation with an adjoining building in spite of a designed construction joint.

Experimental Evaluation of the Effect of Steel-Seal and Hydro-Seal in Reinforced Concrete Structures (STEEL-SEAL 및 HYDRO-SEAL의 철근콘크리트 구조무에 미치는 영향에 대한 실험적 연구)

  • 전환석;이강균;배수호;정영수
    • Proceedings of the Korea Concrete Institute Conference
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    • 1997.10a
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    • pp.287-292
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    • 1997
  • Recent economic growths have accelerating much construction activities of various infrastructures, such as Express railway, Long-span bridges, Multi-story Buildings and etc. Reinforcement steel corrosion to be inevitably caused under the progress of these construction activities have been on and off serious problems in the site, which could incur another tragedic accident to us suffering from safety-ignorance disease. Thus, it is strongly requested to develop probable innovative products which could remove corrosive materials on rebars and also protect steel corrosion of reinforced concrete structures in the construction site. Hydro-Seal and Steel-Seal could solve these problems currently faced with in the construction site. The objective of this research is to experimentally evaluated the effect of Hydro-Seal and Steel-Seal in reinforced concrete structures, of which usage might affect the bond strength between steel and concrete, long-term compressive strength of concrete, corrosion resistance and etc. Related test results show that appropriate dosage of Hydro-Seal and Steel-Seal in reinforced concrete structures didnot affect physical properties of reinforced concrete structures.

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A development of modification program for steel fiber reinforced shotcrete during design and construction stages (강섬유 숏크리트의 설계 및 시공에 대한 문제점 및 개선방향에 대한 연구)

  • Kim, Sang-Hwan;Youn, Seung-Ki
    • Proceedings of the Korean Geotechical Society Conference
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    • 2009.03a
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    • pp.48-57
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    • 2009
  • The quality control of tunnel support construction is very important to maintain a long term stability of tunnel. Especially, steel fiber reinforced shotcrete should be necessary to investigate practically the condition of quality control in the construction site. In order to perform this study, the design criteria and specifications relevant to steel fiber reinforced shotcrete are reviewed. And the comparison is made between the bearing capacity of the several shotcrete layers, based on the equivalence of the bending moments. Eight tunnel construction sites are also investigated carefully to examine and analyse the characteristics of steel fiber reinforced shotcrete especially including strength and mixing condition of steel fiber. Based on the results, it is founded the items to be improved in the future. In addition, the modification program for the specifications of steel fiber reinforced shotcrete is suggested.

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Automation Technology Application for Efficient Project Management of Steel Framing High-rise Building Construction (고층 철골공사의 사업관리 효율화를 위한 자동화 기술 적용 방안 연구)

  • Kim, Chane-Seop;Yun, Seok-Heon
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2010.05a
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    • pp.3-4
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    • 2010
  • With improvements of information technology, the cases which automation technology are applied to construction site are increased. These technologies have advantages and limitations for construction site, therefore they has to be considered in order to maximize benefit. This study are to suggest the process for optimizing management of steel framing high-rise building construction.

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Nonlinear time-varying analysis algorithms for modeling the behavior of complex rigid long-span steel structures during construction processes

  • Tian, Li-Min;Hao, Ji-Ping
    • Steel and Composite Structures
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    • v.18 no.5
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    • pp.1197-1214
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    • 2015
  • There is a great difference in mechanical behavior between design model one-time loading and step-by-step construction process. This paper presents practical computational methods for simulating the structural behavior of long-span rigid steel structures during construction processes. It introduces the positioning principle of node rectification for installation which is especially suitable for rigid long-span steel structures. Novel improved nonlinear analytical methods, known as element birth and death of node rectification, are introduced based on several calculating methods, as well as a forward iteration of node rectification method. These methods proposed in this paper can solve the problem of element's 'floating' and can be easily incorporated in commercial finite element software. These proposed methods were eventually implemented in the computer simulation and analysis of the main stadium for the Universiade Sports Center during the construction process. The optimum construction scheme of the structure is determined by the improved algorithm and the computational results matched well with the measured values in the project, thus indicating that the novel nonlinear time-varying analysis approach is effective construction simulation of complex rigid long-span steel structures and provides useful reference for future design and construction.

Productivity Measurement and Analysis on Factors in Steel Erection (철골세우기의 현장생산성 측정 및 영향요인 분석)

  • Lee, Ji-Yong;Huh, Young Ki;Ahn, Bang Ryul
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2008.11a
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    • pp.123-127
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    • 2008
  • As buildings becoming higher and more enormous the portion of steel works has been increased, which makes the schedule planning and management more significant. However, in actual construction sites, management is more based on a manager's construction experience than productivity data accumulated in previous projects. Moreover, most of the existing studies also featured a theoretical approach rather than an analysis of data straightforwardly collected in sites. In this study, a steel-erection site was visited to collect productivity data. The study found that there were significant disparities between aboveground work productivity and underground work. However, the productivities of 'first node on ground' and 'second node on ground' were estimated similar. The productivity data collected and factors affecting the productivity will help managers to plan and control their similar steel-erection works. This study will also be beneficial for those performing related studies.

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CALS oriented design/fabrication information system for steel bridges

  • Isohata, Hiroshi;Fukuda, Masahiko;Watanabe, Sueo
    • Steel and Composite Structures
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    • v.3 no.1
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    • pp.13-32
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    • 2003
  • In this paper design and fabrication information system for steel bridge construction is studied and proposed according to the progress of Construction CALS/EC in the construction industry in Japan. The data exchange in this system bases on the text file as well as CAD data with simplified drawings. The concept of this system is discussed following the analysis on the issues of the conventional system. The application of the product model is also discussed including effects and issues on the inspection system. This paper is based on the study carried out by Special Committee on Construction CALS of JASBC to which author belong.