• Title/Summary/Keyword: Civil structures construction

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A Study on the Application Case in Civil Structures of Fiber Reinforced Composites (Bridges) (섬유복합재료(FRP)의 건설 적용 사례 연구(교량편))

  • Han Bog-Kyu;Hong Geon-Ho;Kim Ki-Soo
    • Composites Research
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    • v.19 no.2
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    • pp.35-41
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    • 2006
  • FRPs have been used widely and demonstrated in the field of aero industries etc., and began to be used as new construction materials of civil structures. Pre-stressing tendons, reinforcing bars etc. are all examples of the many diverse applications of FRP in new structures. Especially, 40 of all-FRP bridges were reported. The reason why FRP composites were used fur construction materials of civil structures, has been that the working time and the cost of maintenance can be reduced because of the effect of their lightness and durabilities. The purpose of this paper is to report the examples of the many diverse applications of Fiber Reinforced Plastic in construction materials of civil structures.

A Novel Numerical Method for Considering Friction During Pre-stressing Construction of Cable-Supported Structures

  • Zhao, Zhongwei;Liang, Bing;Yan, Renzhang
    • International journal of steel structures
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    • v.18 no.5
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    • pp.1699-1709
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    • 2018
  • Suspen-dome structures are extensively used due to their superiority over traditional structures. The friction between cable and joints may severely influence the distribution of cable force, especially during the pre-stressing construction period. An accurate and efficient numerical method has not yet been developed that can be used for estimating the influence of friction on cable force distribution. Thus, this study proposes an efficient friction element to simulate friction between cable and joint. A flowchart for estimating the value of friction force is introduced. These novel numerical methods were adopted to estimate the influence of friction on cable force distribution. The accuracy and efficiency of these numerical methods were validated through numerical tests.

Chloride penetration in anchorage concrete of suspension bridge during construction stage

  • Yang, In-Hwan;Yoon, Yong-Sik;Kwon, Seung-Jun
    • Advances in concrete construction
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    • v.10 no.1
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    • pp.13-20
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    • 2020
  • Steel corrosion in embedded steel causes a significant durability problems and this usually propagates to structural degradation. Large-scaled concrete structures, PSC (Pre-stressed Concrete) or RC (Reinforced Concrete) structures, are usually constructed with mass concrete and require quite a long construction period. When they are located near to sea shore, chloride ion penetrates into concrete through direct or indirect exposure to marine environment, and this leads durability problems. Even if the structures are sheltered from chloride ingress outside after construction, the chloride contents which have been penetrated into concrete during the long construction period are differently evaluated from the initially mixed chloride content. In the study, chloride profiles in cores extracted from anchorage concrete block in two large-scaled suspension bridge (K and P structure) are evaluated considering the exposure periods and conditions. Total 21 cores in tendon room and chamber room were obtained, and the acid-soluble chlorides and compressive strength were evaluated for the structures containing construction period around 3 years. The test results like diffusion coefficient and surface chloride content from the construction joint and cracked area were also discussed with the considerations for maintenance.

An experimental study on structural behaviour of the MMA double wide flanged GFRP pipe composite structures (II) (MMA 이중 플랜지를 갖는 GFRP 복합관 구조거동에 관한 실험 연구 (II))

  • Ji, Hyo-Seon;Mamdouh, El-Badry
    • Journal of the Korean Society for Advanced Composite Structures
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    • v.6 no.3
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    • pp.50-61
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    • 2015
  • This paper presents on the structural behavior of the the methyl methacrylate monomer (MMA) double wide flanged the glass fiber-reinforced polymer(GFRP) pipe composite structures for the manhole raise. The evaluation of structural performance on this composite structure was conducted by the axial load, fatigue load, and ultimate load test. The assessment indicates that the MMA double wide flanged GFRP pipe composite structures was confirmed safety, durability and reliability in result as expected. It was found that this composite structure was able to short working times to around 30-50% and construction costs to around 10-23% with compare other construction methods. Also, environmental pollution and civil complaints will be prevented because there will be no longer any noises, vibrations, dust, or construction wastes.

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.

Mechanically fastened shear connectors in prefabricated concrete slabs - experimental analysis

  • Gluhovic, Nina;Markovic, Zlatko;Spremic, Milan;Pavlovic, Marko
    • Steel and Composite Structures
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    • v.36 no.4
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    • pp.369-381
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    • 2020
  • Nowadays, in prefabricated composite construction, composite action between steel beam and concrete slab is often achieved with positioning of shear connectors in envisaged openings of concrete slabs. Prefabricated concrete slabs are used for composite steel-concrete buildings and bridges, both for the construction of new structures and for renovation of existing ones, significantly reducing construction time. Development of different types of shear connectors represent alternative solution to the traditionally used headed studs, considering their shear resistance, stiffness and ductility. New types of shear connectors tend to reduce the construction time and overall construction cost. Mechanically fastened shear connectors represent a viable alternative to headed studs, considering their fast installation process and shear resistance. X-HVB shear connectors are attached to the steel beam with two cartridge fired pins. The first step towards extensive implementation of X-HVB shear connectors in composite construction is to understand their behaviour through experimental investigation. Results of the push-out tests, in accordance to Eurocode 4, with X-HVB 110 shear connectors positioned in envisaged openings of prefabricated concrete slabs are presented in this paper. The experimental investigation comprised three different specimen's layout. Group arrangement of X-HVB shear connectors in envisaged openings included specimens with minimal recommended distances and specimens with reduced distances between connectors in both directions. Influence of different installation procedures on overall behaviour of the connection is presented, as well as the orientation of shear connectors relative to the shear force direction. Influence of variations is characterized in terms of failure mechanisms, shear resistance and ductility.

Seismic performance evaluation of buckling restrained braced frames (BRBF) using incremental nonlinear dynamic analysis method (IDA)

  • Khorami, M.;Khorami, M.;Alvansazyazdi, M.;Shariati, M.;Zandi, Y.;Jalali, A.;Tahir, M.M.
    • Earthquakes and Structures
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    • v.13 no.6
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    • pp.531-538
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    • 2017
  • In this paper, the seismic behavior of BRBF structures is studied and compared with special concentric braced frames (SCBF). To this purpose, three BRBF and three SCBF structures with 3, 5 and 10 stories are designed based on AISC360-5 and modelled using OpenSees. These structures are loaded in accordance with ASCE/SEI 7-10. Incremental nonlinear dynamic analysis (IDA) are performed on these structures for 28 different accelerograms and the median IDA curves are used to compare seismic capacity of these two systems. Results obtained, indicates that BRBF systems provide higher capacity for the target performance level in comparison with SCBF systems. And structures with high altitude (in this study, 5 and 10 stories) with the possibility of exceeding the collapse prevention performance level, further than lower altitude (here 3 floors) structures.

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.

Carbonation depth in 57 years old concrete structures

  • Medeiros-Junior, Ronaldo A.;Lima, Maryangela G.;Yazigi, Ricardo;Medeiros, Marcelo H.F.
    • Steel and Composite Structures
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    • v.19 no.4
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    • pp.953-966
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    • 2015
  • Carbonation depth was verified in 40 points of two 57 years old concrete viaducts. Field testing (phenolphthalein spraying) was performed on the structures. Data obtained were statistically analyzed by the Kolmogrov-Smirnov's test, one-way analysis of variance (ANOVA's test), and Fisher's method. The results revealed significant differences between maximum carbonation depths of different elements of the same concrete structure. Significant differences were also found in the carbonation of different concrete structures inserted in the same macroclimate. Microclimatic factors such as temperature and local humidity, sunshine, wind, wetting and drying cycles, among others, may have been responsible by the behavior of carbonation in concrete.

SHM by DOFS in civil engineering: a review

  • Rodriguez, Gerardo;Casas, Joan R.;Villalba, Sergi
    • Structural Monitoring and Maintenance
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    • v.2 no.4
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    • pp.357-382
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    • 2015
  • This paper provides an overview of the use of different Distributed Optical Fiber Sensor systems (DOFSs) to perform Structural Health Monitoring (SHM) in the specific case of civil engineering structures. Nowadays, there are several methods available for extracting distributed measurements from optical fiber, and their use have to be according with the aims of the SHM performance. The continuous-in-space data is the common advantage of the different DOFSs over other conventional health monitoring systems and, depending on the particular characteristics of each DOFS, a global and/or local health structural evaluation is possible with different accuracy. Firstly, the fundamentals of different DOFSs and their principal advantages and disadvantages are presented. Then, laboratory and field tests using different DOFSs systems to measure strain in structural elements and civil structures are presented and discussed. Finally, based on the current applications, conclusions and future trends of DOFSs in SHM in civil structures are proposed.