Pub Date : 2015-10-30DOI: 10.5804/LHIJ.2015.6.4.231
C. Chun, Jong-Yeob Kim, Jong-Dae Bang, Gap-Deug Kim
Recently, It has been much interest in modular housing construction. so, The purpose of this study was to investigate the characteristics of the indoor air quality in modular mock-up housing. We measured indoor air quality(formaldehyde, benzene, toluene, ethylbenzene, xylene, styrene) of two modular mock-up units that built-in furniture is installed and uninstalled. As a result, the pollutants of built-in furniture installed unit were emitted more than built-in furniture uninstalled unit. But after bake-out and ventilation, emission concentrations of two modular mock-up units were similar and were below Indoor Air Quality recommendation standards. Built-in furniture is likely to affect the emission concentration of toluene
{"title":"A Study on Measurement of the Indoor Air Quality in Modular Mock-up Housing","authors":"C. Chun, Jong-Yeob Kim, Jong-Dae Bang, Gap-Deug Kim","doi":"10.5804/LHIJ.2015.6.4.231","DOIUrl":"https://doi.org/10.5804/LHIJ.2015.6.4.231","url":null,"abstract":"Recently, It has been much interest in modular housing construction. so, The purpose of this study was to investigate the characteristics of the indoor air quality in modular mock-up housing. We measured indoor air quality(formaldehyde, benzene, toluene, ethylbenzene, xylene, styrene) of two modular mock-up units that built-in furniture is installed and uninstalled. As a result, the pollutants of built-in furniture installed unit were emitted more than built-in furniture uninstalled unit. But after bake-out and ventilation, emission concentrations of two modular mock-up units were similar and were below Indoor Air Quality recommendation standards. Built-in furniture is likely to affect the emission concentration of toluene","PeriodicalId":365439,"journal":{"name":"LHI journal of land, housing, and urban affairs","volume":"144 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133470788","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-07-30DOI: 10.5804/LHIJ.2015.6.3.117
Ok-yeon Kim, Yong-tai Kim, Yong-Soon Kim
Korean government has launched a new public rental housing policy for younger generation suffering from instable housing conditions in CBD area. This paper is to analyze the financial feasibility of urban public rental housing projects, based on its cash flows. Urban rental housing projects should find out the way to reduce costs and to secure cheap land, because of the high land price in CBD area and complex relationship of legal rights. Project types are categorized by the land acquisition method and district characteristics. For 10 sample projects, financial feasibility was analyzed. Cash flows were calculated on the design plan and 16 scenarios were made by combining 4 important variables. The variables are increase rate of land price, increase rate of monthly rents, ratio of public and market rents, and the interest rate of National Housing Fund. The findings are as follows. Government land rent-type can reduce initial costs because it is not necessary to buy land. However, total NPV is lowered at the time of liquidation due to the land return. Private land acquisition-type require more initial costs. But the NPV at liquidation time increases with land disposal. To improve financial feasibility, acquisition-type should be preferred in high land-price area and rent-type should be preferred in low land-price area. Among influencing variables, the rate of increase in land price and the ratio of public and market rents turned out to be the most important. Although the ratio of public and market rents can be controllable, high ratio will cause the burden of tenants. Therefore, interest rate adjustment of National Housing Fund is more desirable.
{"title":"The Feasibility Analysis of Urban Public Rental Housing in Korea","authors":"Ok-yeon Kim, Yong-tai Kim, Yong-Soon Kim","doi":"10.5804/LHIJ.2015.6.3.117","DOIUrl":"https://doi.org/10.5804/LHIJ.2015.6.3.117","url":null,"abstract":"Korean government has launched a new public rental housing policy for younger generation suffering from instable housing conditions in CBD area. This paper is to analyze the financial feasibility of urban public rental housing projects, based on its cash flows. Urban rental housing projects should find out the way to reduce costs and to secure cheap land, because of the high land price in CBD area and complex relationship of legal rights. Project types are categorized by the land acquisition method and district characteristics. For 10 sample projects, financial feasibility was analyzed. Cash flows were calculated on the design plan and 16 scenarios were made by combining 4 important variables. The variables are increase rate of land price, increase rate of monthly rents, ratio of public and market rents, and the interest rate of National Housing Fund. The findings are as follows. Government land rent-type can reduce initial costs because it is not necessary to buy land. However, total NPV is lowered at the time of liquidation due to the land return. Private land acquisition-type require more initial costs. But the NPV at liquidation time increases with land disposal. To improve financial feasibility, acquisition-type should be preferred in high land-price area and rent-type should be preferred in low land-price area. Among influencing variables, the rate of increase in land price and the ratio of public and market rents turned out to be the most important. Although the ratio of public and market rents can be controllable, high ratio will cause the burden of tenants. Therefore, interest rate adjustment of National Housing Fund is more desirable.","PeriodicalId":365439,"journal":{"name":"LHI journal of land, housing, and urban affairs","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115032941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-07-30DOI: 10.5804/LHIJ.2015.6.3.129
Doo-sung Lee, Sang-Yeon Kim, Tae-Kyun Kim
The building structure in Korea is planned to maximize the use of space in recent. The hybrid OCB(Optimized Composite Beam) beam is developed to take advantage of using the space. The OCB beam is composed of the steel H-beam section reinforced by open strands in negative moment zone and the pretensioned PSC concrete section in positive zone. Flexural behavior of typical architectural hybrid OCB beam section was investigated by F.E.M. The 15m, 20m, 30m OCB models were tested on nonlinear material and geometry under static loading system. Following results are obtained from the analysis; 1)The OCB beam develop initial flexural cracking over full service loading. 2)Overall deflections of OCB beam under the service loads are less than those of the allowable limits in KCI Code(2012). 3)The ultimate load capacity get over the nominal strength of the OCB main section. The OCB beam is verified of structural reliability from the finite element analysis.
{"title":"Development of Hybrid OCB Beam for the Long-span Building Structures","authors":"Doo-sung Lee, Sang-Yeon Kim, Tae-Kyun Kim","doi":"10.5804/LHIJ.2015.6.3.129","DOIUrl":"https://doi.org/10.5804/LHIJ.2015.6.3.129","url":null,"abstract":"The building structure in Korea is planned to maximize the use of space in recent. The hybrid OCB(Optimized Composite Beam) beam is developed to take advantage of using the space. The OCB beam is composed of the steel H-beam section reinforced by open strands in negative moment zone and the pretensioned PSC concrete section in positive zone. Flexural behavior of typical architectural hybrid OCB beam section was investigated by F.E.M. The 15m, 20m, 30m OCB models were tested on nonlinear material and geometry under static loading system. Following results are obtained from the analysis; 1)The OCB beam develop initial flexural cracking over full service loading. 2)Overall deflections of OCB beam under the service loads are less than those of the allowable limits in KCI Code(2012). 3)The ultimate load capacity get over the nominal strength of the OCB main section. The OCB beam is verified of structural reliability from the finite element analysis.","PeriodicalId":365439,"journal":{"name":"LHI journal of land, housing, and urban affairs","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132713777","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-07-30DOI: 10.5804/LHIJ.2015.6.3.139
Jongbae Park, Bum-Sik Lee, Yong-Boo Park
ABSTRACT To improve the pile design efficiency(design bearing capacity⁄the strength of materials) from 70 percent(160tonf) to 80 percent(190tonf), this paper analysed the existing pile loading test data and performed the precise dynamic loading test and Bi-directional loading test for the first time in Korea. Analysis result of the existing dynamic loading test data by Davisson method showed that bearing capacity of piles penetrated at weathered rock stratum(N=50/15) exceeded 190tonf. But the analysis result by CAPWAP method showed that piles less than the target bearing capacity were 40% due to the lack of impact energy. To get the target bearing capacity from the dynamic loading test, using the hammer over 6tonf to trigger the enough impact energy is necessary. Allowable bearing capacty of Bi-directional static loading test by Davisson method was 260.0~335tonf(ave. 285.3tonf) and exceeded overwhelmingly the target capacity. And this exceeded the bearing capacity of precise dynamic loading test(ave. 202.3tonf) performed on the same piles over 40%. The difference between the capacity of Bi-directional loading test and dynamic loading test was caused by the insufficient impact energy during dynamic loading test and increase by interlocking effect by near piles during Bi-directional static loading test. Key words : Dynamic Loading Test, Davisson Method, CAPWAP, Bearing Capacity, Striking Energy, Bi-directional Loading Test
{"title":"Analytical Study on the Appropriateness of Design Formula and Possibility of Improving Bearing Capacity of Bored Pile","authors":"Jongbae Park, Bum-Sik Lee, Yong-Boo Park","doi":"10.5804/LHIJ.2015.6.3.139","DOIUrl":"https://doi.org/10.5804/LHIJ.2015.6.3.139","url":null,"abstract":"ABSTRACT To improve the pile design efficiency(design bearing capacity⁄the strength of materials) from 70 percent(160tonf) to 80 percent(190tonf), this paper analysed the existing pile loading test data and performed the precise dynamic loading test and Bi-directional loading test for the first time in Korea. Analysis result of the existing dynamic loading test data by Davisson method showed that bearing capacity of piles penetrated at weathered rock stratum(N=50/15) exceeded 190tonf. But the analysis result by CAPWAP method showed that piles less than the target bearing capacity were 40% due to the lack of impact energy. To get the target bearing capacity from the dynamic loading test, using the hammer over 6tonf to trigger the enough impact energy is necessary. Allowable bearing capacty of Bi-directional static loading test by Davisson method was 260.0~335tonf(ave. 285.3tonf) and exceeded overwhelmingly the target capacity. And this exceeded the bearing capacity of precise dynamic loading test(ave. 202.3tonf) performed on the same piles over 40%. The difference between the capacity of Bi-directional loading test and dynamic loading test was caused by the insufficient impact energy during dynamic loading test and increase by interlocking effect by near piles during Bi-directional static loading test. Key words : Dynamic Loading Test, Davisson Method, CAPWAP, Bearing Capacity, Striking Energy, Bi-directional Loading Test","PeriodicalId":365439,"journal":{"name":"LHI journal of land, housing, and urban affairs","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123676361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-07-30DOI: 10.5804/LHIJ.2015.6.3.107
Jong-Lim Kim, Han-Jin Cho, Soon-Woo So
{"title":"Erratum : A Study on the Demand Zone of Housing for New Town: Focused on Seoul Metropolitan Area","authors":"Jong-Lim Kim, Han-Jin Cho, Soon-Woo So","doi":"10.5804/LHIJ.2015.6.3.107","DOIUrl":"https://doi.org/10.5804/LHIJ.2015.6.3.107","url":null,"abstract":"","PeriodicalId":365439,"journal":{"name":"LHI journal of land, housing, and urban affairs","volume":"123 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129631299","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-07-30DOI: 10.5804/LHIJ.2015.6.3.147
Sang-Yeon Kim, Jongbae Park, Yong-Boo Park
ABSTRACT Site coefficient and amplification factor of current domestic Seismic Design Code based on American Seismic Code, have no consideration for the domestic ground condition in which the base rock is normally placed within 30m form the surface. By previous studies, the measured spectral acceleration of the result of dynamic centrifugal test and analysis was smaller than the design spectral acceleration for the period over 1.5 sec. Accordingly, in this study structural analysis and design using dynamic centrifugal test result for pile foundation were achieved, and the quantity of concrete and reinforcement of wall frame was compared with each other. Comparison results of cost using KBC the design spectral acceleration of SC, SD site and SDS, the quantity of reinforcement using SDS for SD site was 17~23% smaller than using the design code SD site. Key words : Pile Foundation, Dynamic Test, Site Coefficient, Design Spectral Acceleration, Cost Compare 1) 한국토지주택공사 토지주택연구원 수석연구원(주저자: sy-kim@lh.or.kr)2) 한국토지주택공사 토지주택연구원 수석연구원(교신저자: jbpark@lh.or.kr)3) 한국토지주택공사 토지주택연구원 수석연구원
{"title":"Comparative Study on the Quantity Economic Analysis of Apartment Frames Using SDS Result of Dynamic Centrifuge Test at Pile Foundation","authors":"Sang-Yeon Kim, Jongbae Park, Yong-Boo Park","doi":"10.5804/LHIJ.2015.6.3.147","DOIUrl":"https://doi.org/10.5804/LHIJ.2015.6.3.147","url":null,"abstract":"ABSTRACT Site coefficient and amplification factor of current domestic Seismic Design Code based on American Seismic Code, have no consideration for the domestic ground condition in which the base rock is normally placed within 30m form the surface. By previous studies, the measured spectral acceleration of the result of dynamic centrifugal test and analysis was smaller than the design spectral acceleration for the period over 1.5 sec. Accordingly, in this study structural analysis and design using dynamic centrifugal test result for pile foundation were achieved, and the quantity of concrete and reinforcement of wall frame was compared with each other. Comparison results of cost using KBC the design spectral acceleration of SC, SD site and SDS, the quantity of reinforcement using SDS for SD site was 17~23% smaller than using the design code SD site. Key words : Pile Foundation, Dynamic Test, Site Coefficient, Design Spectral Acceleration, Cost Compare 1) 한국토지주택공사 토지주택연구원 수석연구원(주저자: sy-kim@lh.or.kr)2) 한국토지주택공사 토지주택연구원 수석연구원(교신저자: jbpark@lh.or.kr)3) 한국토지주택공사 토지주택연구원 수석연구원","PeriodicalId":365439,"journal":{"name":"LHI journal of land, housing, and urban affairs","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121575481","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-10-30DOI: 10.5804/LHIJ.2014.5.4.325
C. Chun, Gil-Tae Kim, Sun-Dong Kim
The purpose of this study was to measure the airtightness and Air-Flow Performance for 7th house of small apartment houses adopted window frame-type natural ventilation. All window and living room door is provide with window frame-type natural ventilation, and there is provide with manual controller. As the object of measurement, the 6th type small apartment houses with area of 33 ㎡ to 51 ㎡ was selected. airtightness performance was measured at the front door using Blower door system. We measured ventilation rate per hour on 50Pa pressure different between inside and outside by the 1st to 6th cases. As a result, when the natural ventilation frame was closed, average amounts are shown as the ventilation rate per hour were 2.27ACH (CASE1). and the result is similar to general apartment house (1.65~4.28ACH). When the natural ventilation frame was open, average amounts are shown as the ventilation rate per hour were 5.87ACH (CASE6). In addition, that's a 3.6ACH increased more than CASE1.
{"title":"A Study of Measurement on Airtightness and Air-Flow Performance of Apartment Housing Adopting Window Frame-Type Natural Ventilation","authors":"C. Chun, Gil-Tae Kim, Sun-Dong Kim","doi":"10.5804/LHIJ.2014.5.4.325","DOIUrl":"https://doi.org/10.5804/LHIJ.2014.5.4.325","url":null,"abstract":"The purpose of this study was to measure the airtightness and Air-Flow Performance for 7th house of small apartment houses adopted window frame-type natural ventilation. All window and living room door is provide with window frame-type natural ventilation, and there is provide with manual controller. As the object of measurement, the 6th type small apartment houses with area of 33 ㎡ to 51 ㎡ was selected. airtightness performance was measured at the front door using Blower door system. We measured ventilation rate per hour on 50Pa pressure different between inside and outside by the 1st to 6th cases. As a result, when the natural ventilation frame was closed, average amounts are shown as the ventilation rate per hour were 2.27ACH (CASE1). and the result is similar to general apartment house (1.65~4.28ACH). When the natural ventilation frame was open, average amounts are shown as the ventilation rate per hour were 5.87ACH (CASE6). In addition, that's a 3.6ACH increased more than CASE1.","PeriodicalId":365439,"journal":{"name":"LHI journal of land, housing, and urban affairs","volume":"472 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121127196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-10-30DOI: 10.5804/LHIJ.2014.5.4.291
Gil-Tae Kim, Jong-yeob Kim, H. Hwang, Kyoung-Sik Kim
{"title":"The Design Criteria of the Indoor Temperature and Humidity for the Prevent Condensation of Small Apartment Buildings","authors":"Gil-Tae Kim, Jong-yeob Kim, H. Hwang, Kyoung-Sik Kim","doi":"10.5804/LHIJ.2014.5.4.291","DOIUrl":"https://doi.org/10.5804/LHIJ.2014.5.4.291","url":null,"abstract":"","PeriodicalId":365439,"journal":{"name":"LHI journal of land, housing, and urban affairs","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116475404","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-10-30DOI: 10.5804/LHIJ.2014.5.4.247
K. Ji, So-Young Lee, Yong-Soon Kim
This study proposes a new housing need and demand assessment model centering on small-scale housing development projects and happy house development projects that reflected the recent changes in rental and small sized apartment centered public housing policies and development paradigms. The housing need and demand assessment model of public housing development projects consists of quantitative evaluation factors such as potential need indicator and demand pressure indicator and qualitative evaluation factors such as local condition indicator. The potential need indicators of small sized housing development projects are calculated by subtracting the stock of already-supplied constructed rental and purchased rental housings from the potential quantity of need drawn from the small regions such as -eup, -myeon, and -dong. In the potential need indicators of happy house development projects, the potential need is calculated from those who are expected to receive a happy house in the unit of -si, -gun, and -gu. In small-sized housing development projects, demand pressure indictors are the number and the proportion of those who opened a subscription deposit, the number of those who received basic livelihood security and the number of those who were patriots and veterans. The demand pressure indicators of the happy house development projects are stock ratio of small-sized houses, rate of rise in housing rent price, level of housing rent price, and rate of monthly rent house.
{"title":"Housing Need and Demand Assessment: Focused on Public Housing Development Projects","authors":"K. Ji, So-Young Lee, Yong-Soon Kim","doi":"10.5804/LHIJ.2014.5.4.247","DOIUrl":"https://doi.org/10.5804/LHIJ.2014.5.4.247","url":null,"abstract":"This study proposes a new housing need and demand assessment model centering on small-scale housing development projects and happy house development projects that reflected the recent changes in rental and small sized apartment centered public housing policies and development paradigms. The housing need and demand assessment model of public housing development projects consists of quantitative evaluation factors such as potential need indicator and demand pressure indicator and qualitative evaluation factors such as local condition indicator. The potential need indicators of small sized housing development projects are calculated by subtracting the stock of already-supplied constructed rental and purchased rental housings from the potential quantity of need drawn from the small regions such as -eup, -myeon, and -dong. In the potential need indicators of happy house development projects, the potential need is calculated from those who are expected to receive a happy house in the unit of -si, -gun, and -gu. In small-sized housing development projects, demand pressure indictors are the number and the proportion of those who opened a subscription deposit, the number of those who received basic livelihood security and the number of those who were patriots and veterans. The demand pressure indicators of the happy house development projects are stock ratio of small-sized houses, rate of rise in housing rent price, level of housing rent price, and rate of monthly rent house.","PeriodicalId":365439,"journal":{"name":"LHI journal of land, housing, and urban affairs","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132662968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}