• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.1
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• pp.116-124
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• 2020

In order to analyze the lateral-load resisting capability according to the core locations, three-dimensional structural analyses were performed for 20-story buildings with symmetric plan. Four analytical models for a center core, a single-axial eccentric core, and a double-axial eccentric core were constructed, and eigenvalue analyses, wind-load analyses, and earthquake-load analyses were performed. Torsion did not occur in the central core building, but the bending and torsion occurred in combination with the arrangement of the eccentric core, and the lateral-load resisting capability was degraded. The change in the wind load according to the eccentric core was small, but the maximum lateral displacement was found to increase greatly by the eccentric arrangement of the core. In addition, in case of the eccentric core, the seismic load was slightly reduced compared to the center core due to the decrease in the lateral stiffness, but it was found that the maximum story drift ratio increased significantly due to the torsional effect. Based on these results, the structural behavior according to the position of the core can be clearified and used as a guideline for core locations in the planning and design stage.

• Cross-Cultural Studies
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• v.21
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• pp.7-29
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• 2010

Young Tolstoy, when he was an already well-known writer, accomplished his first overseas travel in 1857, which gave him imaginable opportunities to compare his country's social strata with others such as serfdom, monarchical Russia and industrial and capital Europe. The present story is, indeed, the work which is influenced by those experiences by young Tolstoy during his first journey into Europe. Written in the form of booklet-like-small-piece, rather than an artistic work, the text presents the writer's severe criticism on the world of nature and civilization. Close to the nature itself, narod are those common people for Tolstoy, and they represent love, while the nature creates a necessity to love, hope and bottomless happiness of life. On the contrary, the civilized or civilization itself is considered artificial, willy, reasonal, and erotic congruity among people. For the writer, the most unsafe and ugly, seamy side of the westernized society is a lack of necessity to unify people to people. Though in its early embryonic stage, young Tolstoy's worldview is reflected in this work, especially his sharp tongue on the western people and their society is also detected when the write imposes his message under the mask of a gypsy singer. In addition, the narrator who seems an obvious Tolstoy's mouthpiece delivers his own ideas and impression on the western world, history, art, and literature. For this very reason, the present work contains numerous signs from which the reader is able to interpret, understand, and figure out what young Tolstoy imposes for his work.

• Structural Engineering and Mechanics
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• v.77 no.1
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• pp.115-135
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• 2021

This paper focuses on examining the effects of span arrangements on displacement responses of plan-symmetric RC frame buildings designed using the direct displacement-based design (DDBD) method by employing non-linear analyses and the skew seismic attack. In order to show the desired performance of DDBD design approach, the force-based design approach is also used to examine the seismic performance of the selected structures. To realize this objective, 8-story buildings with different plans are selected. In addition, the dynamic behavior of the structures is evaluated by selecting 3, 7, and 12-story buildings. In order to perform non-linear analyses, OpenSees software is used for modeling buildings. Results of an experimental model are used to validate the analytical model implemented in OpenSees. The results of non-linear static and non-linear dynamic analyses indicate that changing span arrangements does not affect estimating the responses of structures designed using the DDBD approach, and the results are more or less the same. Next, in order to apply the earthquake in non-principle directions, DDBD structures, designed for one-way performance, are designed again for two-way performance. Time history analyses are performed under a set of artificial acceleration pairs, applied to structures at different angles. It is found that the mean maximum responses of earthquakes at all angles have very good agreement with the design-acceptable limits, while the response of buildings along the height direction has a relatively acceptable and uniform distribution. Meanwhile, changes in the span arrangements did not have a significant effect on displacement responses.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.35 no.2
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• pp.119-129
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• 2022

It is essential to control the lateral displacement and differential axial shortening of the vertical elements in high-rise buildings. The differential axial shortening can cause challenges in the serviceability and safety of non-structural and structural elements, respectively. Hence, in this study, the differential axial shortening of the vertical elements and effects of long term behaviors of concrete are analyzed in 120-story high-rise buildings via the construction sequence analysis. Consequently, the axial shortening of the vertical elements is classified into elastic, creep, and shrinkage shortening, and dominant factors to the maximum axial shortening are analyzed. In addition, the serviceability of the non -structural elements is checked with a differential axial shortening at 30 years after completion of construction, and member forces at design and construction stages in girders and outrigger walls are compared.

• Structural Engineering and Mechanics
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• v.78 no.3
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• pp.351-368
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• 2021

This paper, by applying a reliability-based framework, develops seismic vulnerability macrozonation maps for Tehran, the capital and one of the most earthquake-vulnerable city of Iran. Seismic performance assessment of 3-, 4- and 5-story steel moment resisting frames (SMRFs), designed according to ASCE/SEI 41-17 and Iranian Code of Practice for Seismic Resistant Design of Buildings (2800 Standard), is investigated in terms of overall maximum inter-story drift ratio (MIDR) and unit repair cost ratio which is hereafter known as "damage ratio". To this end, Tehran city is first meshed into a network of 66 points to numerically locate low- to mid-rise SMRFs. Active faults around Tehran are next modeled explicitly. Two different combination of faults, based on available seismological data, are then developed to explore the impact of choosing a proper seismic scenario. In addition, soil effect is exclusively addressed. After building analytical models, reliability methods in combination with structure-specific probabilistic models are applied to predict demand and damage ratio of structures in a cost-effective paradigm. Due to capability of proposed methodology incorporating both aleatory and epistemic uncertainties explicitly, this framework which is centered on the regional demand and damage ratio estimation via structure-specific characteristics can efficiently pave the way for decision makers to find the most vulnerable area in a regional scale. This technical basis can also be adapted to any other structures which the demand and/or damage ratio prediction models are developed.

• Steel and Composite Structures
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• v.45 no.3
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• pp.437-454
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• 2022

Elliptic-braced simple resisting frame as a new lateral bracing system installed in the middle bay of frame in building facades has been recently introduced. This system not only creates a problem for opening space from the architectural viewpoint but also improves the structural behavior. Despite the researches on the seismic performance of lateral bracing systems, there are few studies performed on the effect of the stiffness parameters on the elastic story drift and calculation of period in simple braced steel frames. To overcome this shortcoming, in this paper, for the first time, an analytical solution is presented for calculating elastic lateral stiffness in a simple steel frame equipped with elliptic brace subjected to lateral load. In addition, for the first time, in this study, a precise formulation has been developed to evaluate the elastic stiffness variation in a steel frame equipped with a two-dimensional single-story single-span elliptic brace using strain energy and Castigliano's theorem. Thus, all the effective factors, including axial and shear loads as well as bending moments of elliptic brace could be considered. At the end of the analysis, the lateral stiffness can be calculated by an improved and innovative relation through the energy method based on the geometrical properties of the employed sections and specification of the used material. Also, an equivalent element of an elliptic brace was presented for the ease of modeling and use in linear designs. Application of the proposed relation have been verified through a variety of examples in OpenSees software. Based on the results, the error percentage between the elastic stiffness derived from the developed equations and the numerical analyses of finite element models was very low and negligible.

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.3
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• pp.63-74
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• 2008

With the awareness that Sinyeongwol Sipgyeong(ten scenic spots in Yeongwol) were designed too hastily and only for PR purposes after the change in the tourism environment, this paper indicates that most tourism and culture sources in Yeongwol are related to King Danjong, the sixth king of the Joseon Dynasty. This study proposes a 'Storytelling Plan' for the landscape content called 'Cultural Landscapes - Yeongwol Palgyeong(eight scenic spots in Yeongwol)' after reviewing types and content of Yeongwol Palgyeong through the halo effect of the well-known sad history of King Danjong and the cultural value of Yeongwol. The significance of the unity of the historic site and neighboring landscape is focused on by investigating the anaphoric relations between cultural landscape texts('Yeongwol Palgyeong') and historic content(the sad history of King Danjong). For this, the cultural lnddscape of Yeongwol has been framed and layered to make spatial texts. To emphasize the 'Telling' as well as the 'Story,' interesting episodes have been reviewed to discover a motive. To diversify the 'Telling' methods, absorptive landscape factors have been classified as 'Place,' 'Object' and 'Visual Point.' In addition the storytelling of Yeongwol Palgyeong was examined in consideration of the story and background of 'Yeongwol Palgyeong - Sad Story of King Danjong' and the interaction of a variety of cultural content by suggesting micro-content such as infotainment and edutainment as absorptive landscape factors. In order to make the storytelling plan available in practice as an alternative plan for Yeongwol Tourism, a visual point should be properly set to make the landscape look sufficiently dynamic. In addition, real landscape routes and narration scenarios should be prepared as well. Professional landscape interpreters who are well informed of the natural features of Yeongwol and the history of King Danjong should be brought into the project, and Internet and digital technology-based strategies should be developed.

• Structural Engineering and Mechanics
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• v.11 no.3
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• pp.273-286
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• 2001

Viscoelastic (VE) dampers have shown to be capable of providing structures with considerable additional damping to reduce the dynamic response of structures. However, the VE material appears to be sensitive to the variations in ambient temperature and vibration frequency. To minimize these effects, a new VE material has been developed. This new material shows less sensitivity to variations in vibration frequency and temperature. However, it is highly dependent on the shear strain. Experimental studies on the seismic behavior of a 2/5 scale five-story steel frame with these new VE dampers have been carried out. Test results show that the structural response can be effectively reduced due to the added stiffness and damping provided by the new type of VE dampers under both mild and strong earthquake ground motions. In addition, analytical studies have been carried out to describe the strain-dependent behavior of the VE damper. The dynamic properties and hysteresis behavior of the dampers can be simulated by a simple bilinear model based on the equivalent dissipated energy principle proposed in this study.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.11a
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• pp.189-190
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• 2015

Slim Floor construction method has to increase the available surface area thereby reducing the depth beams and slab. In addition, In this study compostie beam assembly of plates, square-shape steel pipe and deck plate. So workabiltiy is superior to the upper concrete possible without formwork. In the present study is strength test in progress in development slim floor composite beam used plate and perforated square shape steel pipe and obtained anlysis and conclustion of the experimental results.

• Journal of the Korean Society of Safety
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• v.27 no.1
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• pp.70-75
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• 2012

For the vibration control of earthquake-excited structures, a pivot-type displacement amplification damper system is proposed and its validity is investigated in this study. A rotational frame amplifies the stroke of the proposed damper system and it can absorb more vibrational energy compared to the conventional dampers of which strokes are not large. In order to prove the effectiveness of the system, time-history analyses are performed with a three story building modelled by a three dimensional frame and numerical results are compared with those for a conventional V-shape braced damper system. In addition, the seismic performances are investigated according to the changes of damper capacity and location.