• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.6
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• pp.106-112
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• 2017

This paper presents a mathematical model derived from the upper-bound theorem of concrete plasticity to rationally evaluate the shear friction strength of concrete interfaces with a construction joint. The upper limit of the shear friction strength was formulated from the limit state of concrete crushing failure on the strut-and-tie action along the construction joints to avoid overestimating the shear transfer capacity of a transverse reinforcement with a high clamping force. The present model approach proposed that the cohesion and coefficient of friction of concrete can be set to be $0.27(f_{ck})^{0.65}$ and 0.95, respectively, for rough construction joints and $0.11(f_{ck})^{0.65}$ and 0.64, respectively, for smooth ones, where $f_{ck}$ is the compressive strength of concrete. From the comparisons with 155 data compiled from the available literature, the proposed model gave lower values of standard deviation and coefficient of variation of the ratios between predictions and experiments than AASHTO and fib 2010 equations, indicating that the proposed model has consistent trends with test results, unlike the significant underestimation results of such code equations in evaluating the shear friction strength.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.6
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• pp.81-88
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• 2018

The present study evaluated the effective arrangement approach of transverse reinforcement in the jacket section for seismic strengthening of reinforced concrete columns. To simulate the full-scale columns, the section dimensions were determined as $450{\times}450mm$ for non-seismic existing columns and $750{\times}750mm$ for section enlargement strengthening columns. Over-lapped channel-shape bars and prefabricated bar units were proposed for closed-hoops in the jacket section, and conventional cross-ties anchored into existing columns and V-ties were considered for the supplementary ties. Test results showed that the axial capacity of the existing column and section enlargement columns with over-lapped channel-shape hoops was similar to the nominal strength calculated using ACI 318-14 procedure whereas the section enlargement column with prefabricated bar units possessed 1.25 times higher axial capacity than the nominal prediction. Furthermore, the axial ductility ratio of the section enlargement column with prefabricated bar unit was 139% higher than that of the existing column despite the potential size effect on ductility of concrete. Thus, it can be concluded that the developed prefabricated bar unit technique is practically useful for preventing the premature buckling of longitudinal reinforcement and confining core concrete in the section enlargement strengthening columns.

• Archives of design research
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• v.18 no.3 s.61
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• pp.171-180
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• 2005

The purpose of this research is to investigate the nature of direction of the design corresponding to a human-centered design, digitalism, ecological design, and culture-oriented design which is an issue of design in the 21st century, from the design of the inside of a room. As a method of approach to this objective, first, 1 understand the form of boundary structure appearing in space, through the theoretical investigation of a boundary form. This research is trying to elicit the expression characteristic of kineticism which was introduced to the boundary form as a factor constituting space, by investigating the characteristic of kinaticism which was expressed in plastic arts and other genres. As a process of the proceeding of this investigation, It is explained the background, purpose, and method of this study in Chapter I, and look into the characteristic of the unfolding and expression of kinetic arts as well as the structure of a boundary form of space in Chapter II. In Chapter III, I divide the aspect of modern architectural space into realistic movement, relative movement, and associational movement and examine them. In Chapter IV, I investigate a case of modern space in which the three types of the characteristic of movement mentioned in Chapter Three was expressed, and analyze to what boundary structure the space was introduced. Last of all, in Chapter V, I elicit the characteristic of a boundary form of kineticism which was the result that appeared through the above analysis, and present the nature of future direction of interior.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.4
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• pp.83-91
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• 2021

In this study, to improve the connection performance between the existing reinforced concrete (R/C) frame and the strengthening member, we proposed a new H-section steel frame with elastic pad (HSFEP) system for seismic rehabilitation of existing medium-to-low-rise reinforced concrete (R/C) buildings. This HSFEP strengthening system exhibits an excellent connection performance because an elastic pad is installed between the existing structure and reinforcing frame. The method shows a strength design approach implemented via retrofitting, to easily increase the ultimate lateral load capacity of R/C buildings lacking seismic data, which exhibit shear failure mechanism. Two full-size two-story R/C frame specimens were designed based on an existing R/C building in Korea lacking seismic data, and then strengthened using the HSFEP system; thus, one control specimen and one specimen strengthened with the HSFEP system were used. Pseudodynamic tests were conducted to verify the effects of seismic retrofitting, and the earthquake response behavior with use of the proposed method, in terms of the maximum response strength, response displacement, and degree of earthquake damage compared with the control R/C frame. Test results revealed that the proposed HSFEP strengthening method, internally applied to the R/C frame, effectively increased the lateral ultimate strength, resulting in reduced response displacement of R/C structures under large scale earthquake conditions.

• Korean Journal of Heritage: History & Science
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• v.42 no.4
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• pp.50-73
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• 2009

Recently old stone walls were designated as registered cultural properties that meant an extension of categories about cultural properties from a spot area to whole area. Moreover given the changing situation of residential pattern, which is due to rapid social change, this designation can be seen as a significant measure to keep as intact as possible traditional landscapes in agricultural and fishing villages. In this paper, I analyze the symbol system and meaning of old stone walls and attempt to pick out the cultural elements which are related to them. These days we have made efforts to various aspects for which make traditional cultural resources into cultural contents. But many studies had done before emphasized aspects for beauty only. Especially existing studies about an old stone wall was mainly focused on architectural interpretation and tourist route. So we need to build a plot around oral research and need a creative approach for sharing with tourists. Cultural contents combine the original form, potential and capabilities with media by detecting original form of culture and finding out the worth and meaning. In this paper examined the probability of using by investigating a stone wall in Sang-hak Village that is related with recovering of places to live in contemporary society and finding cultural contents. I suggest more creative ways to make cultural properties into tourist resources by considering the possibilities of place marketing using storytelling, based on an analysis of data gathered.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.5
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• pp.591-598
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• 2019

The statistics of committing suicide in S. Korea is ranked in top with serious attempts of falling among OECD countries since 2003. The rates is slightly dropped by 5 percent point, nevertheless the falling is still high for the age of over 10 years old and this matter must be solved. Most of the case of suicides are the falling based on a trend view of falling which is serious matter and cannot be solved easily for both domestic and foreign countries. For example, the steel net of falling prevent was installed in the Golden Gate Bridge costed by 200 million-dollar. In New Zealand, the steel net of falling prevention had been removed and re-installed beccause of the high suicide rates. Canada and Australia also surrounded the bridge with steel fences to prevent suicide without consideration of the beauty of bridge. Therefore, this paper suggested a comparison study on both falling prevention systems in all countries and patent technologies. Also, it covers the blocking skills of approach in both security and limited area. This paper suggested the technical Rollinder system equipped with the mechanical apprentice to prevent effectively the falling sucides and wall passing. Before the installation of Rollinder System by 2016, there were 33 person who tried to fall in the river in Machang Bridge. However, the number of the committing suicides were dramatically reduced to zero after the installation of the system.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.29 no.4
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• pp.137-147
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• 2011

This study aims to find out the construction process and planning characteristics of Suwon and Hwa-sung in 18th century from the point of water system. This study has an explanatory approach. The planning intents in the water system was driven out by analyzing various planning elements in relation to water system in the process of constructing Hwa-sung in 18th century. Using Entire Map of Hwa-sung, land registration map made in 1911 and topographic map of 1/10,000 scale made in 1917, water system and interpretation of spatial structure in Hwa-sung were analyzed. The results are as follows(Planning characteristics of the water system in Haw-sung in 18th century are as follows). Firstly, in determining the spatial structure and location of Hwa-sung, water system had an important role. Secondly, integrated drainage system was planned by the organization of natural and artificial water stream. Thirdly, the main street system and land use structure were planned in relation with water system. Fourthly, territoriality of main area was planned with water stream. Fifthly, ponds were constructed for flood control and they had important role as landscape elements. Sixthly, water stream was used as intentional BiBo element. As a result of the study, the weater system of Hwa-sung in 18th century was planned by the organization of natural and artificial water stream in relation with the location of new town and wide area's spatial structure, street system, land use structure, territoriality of main area, terriflood control, water quality protection, landscape, 비보 and urban daily life.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.3
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• pp.77-84
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• 2021

In this study, flexural tests of prestressed high strength spun concrete (PHC) piles reinforced with infilled concrete and longitudinal rebars were conducted, where the longitudinal rebar ratio and the presence of sludge formed on the inner surface of PHC pile were set as key test variables. A total of six PHC pile specimens were manufactured, and their flexural behaviors including failure mode, crack pattern, longitudinal strain distribution in a section and end slip between external PHC pile and infilled concrete were measured and discussed in detail. The test results revealed that the flexural stiffness and strength increased as the longitudinal rebar ratio became larger, and that the sludge formed on the inner surface of PHC pile did not show any detrimental effect on the flexural performance. In addition to the experimental approach, this study presents a nonlinear flexural analysis model considering compatibility conditions and strain and stress distributions of the PHC piles and infilled concrete. The rationality of the nonlinear flexural analysis model was verified by comparing it with test results, and it appeared that the proposed model well evaluated the flexural behavior of PHC piles reinforced with infilled concrete and longitudinal rebars with a good accuracy.

• Journal of Korea Entertainment Industry Association
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• v.15 no.4
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• pp.113-125
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• 2021

This research has the purpose to approach 'Audience participation theatre' through applying the concept of 'Hybrid' which newly come to the fore after 21st in a theatre space. In fact, 'Hybrid' has been suppling crucial power to create and pass a culture down for a long time, and it could not different to a theatre space. The hybridity in previous traditional theatre which is central 'text' and 'architectural theater' is limited movement only on the stage, such as 'an actor between presence and absence', 'a theatrical time between real and fiction' and 'an objet between An Sich(thing itself) and Fur Sich(thing with inner meaning). However after 20st's 'Avant-Garde' with 'decomposition sprit', the hybridity become broader from only on the stage to entire theatre space including auditorium caused by collapse the boundary between auditorium and stage. In other words, 'auditorium' and 'audience' are considered as 'a theatrical element' coequal with other elements, and it can create various special results through they are mixed equally. Therefore, 'Audience participation theatre' could regarded a kind of hybrid phenomenon between 'auditorium and audience' and 'actor and stage' which are most disparate relation, and it is also approached 'hybridized audience', 'hybridized space' and 'hybridized text' as a new identity.

• Journal of the Korea Institute of Building Construction
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• v.23 no.3
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• pp.221-229
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• 2023

This research aimed to conduct an empirical assessment of the penetration of chloride and sulfate ions into mortar sections using an anion exchange membrane(AEM) and laser-induced breakdown spectroscopy(LIBS). The study involved a simultaneous ion chromatography(IC) analysis and LIBS analysis performed on mortars immersed in varying concentrations of chloride and sulfate. The findings revealed that at the wavelengths specific to Chloride(837.59nm) and Sulfur(921.30nm), the LIBS intensity achieved using AEM surpassed that obtained with a paper substrate at equivalent penetration concentrations. A robust correlation was confirmed between LIBS intensity and chloride ion concentration. Furthermore, when juxtaposed with IC analysis concentration outcomes at identical depths, the AEM displayed a higher intensity. The research noted an enhancement in LIBS intensity and a diminution in errors within the low-concentration section when deploying AEM. However, for the Sulfur wavelength of 921.3nm, there remains a need to augment the sensitivity of the LIBS signal within the low-concentration section in future studies. The findings underscore the potential of employing AEM and LIBS for precise analysis of chloride and sulfate ion penetration into mortar sections. This strategy can aid in bolstering assessment precision and mitigating errors, particularly in regions with low concentrations. It is recommended to further research and develop methods to amplify the sensitivity of the LIBS signal for sulfur detection in low-concentration sections. In sum, the study accentuates the significance of employing advanced techniques like AEM and LIBS for efficacious and precise analysis in the domain of mortar section assessment.