• Title/Summary/Keyword: Concrete Roof

Search Result 179, Processing Time 0.029 seconds

Analysis of surface design and panel optionsfor freeform building

  • Min Gyu Park;Han Guk Ryu
    • International conference on construction engineering and project management
    • /
    • 2013.01a
    • /
    • pp.553-557
    • /
    • 2013
  • Roof and exterior wall are designed and constructed in a manner that prevents the accumulation of water within the wall and roof assembly in the formal building. However, in a freeform building there is no clear distinction between exterior wall and roof. In other words, the exterior walls and roof systems of the freeform building are integrated as a surface, unlike the formal building envelope. Therefore, freeform architecture needs a systemized envelope design method to perform functions of exterior wall and roof. However, in many cases, construction methods for roof and exterior wall are applied to freeform buildings without necessary alterations, which lead to incomplete design, leakage, cracks and other problems. Freeform architecture is thus designed and constructed differently from formal buildings. In order to more easily and inexpensively actualize freeform architecture, Building Information Modeling (hereinafter referred to as BIM) has recently been applied in the construction industry. The studies and case analysis are not sufficient to identify the implications and contributions of freeform buildings in future similar projects. Therefore, this research will study design and construction methods for freeform surfaces. This study attempts to analyze the pros and cons of each method for the concrete surface frame, and then presents the panel options for envelope system of the freeform architecture.

  • PDF

Finite element simulation of traditional and earthquake resistant brick masonry building under shock loading

  • Daniel, A. Joshua;Dubey, R.N.
    • Coupled systems mechanics
    • /
    • v.4 no.1
    • /
    • pp.19-36
    • /
    • 2015
  • Modelling and analysis of a brick masonry building involves uncertainties like modelling assumptions and properties of local material. Therefore, it is necessary to perform a calibration to evaluate the dynamic properties of the structure. The response of the finite element model is improved by predicting the parameter by performing linear dynamic analysis on experimental data by comparing the acceleration. Further, a nonlinear dynamic analysis was also performed comparing the roof acceleration and damage pattern of the structure obtained analytically with the test findings. The roof accelerations obtained analytically were in good agreement with experimental roof accelerations. The damage patterns observed analytically after every shock were almost similar to that of experimental observations. Damage pattern with amplification in roof acceleration exhibit the potentiality of earthquake resistant measures in brick masonry models.

Comparison of Planting Types on an Extensive Green Roof Based on Summer Surface Temperature (저관리 경량형 옥상녹화의 식재 유형별 여름철 표면온도 비교)

  • Han, Yichae;Lee, Binara;Ahn, Geunyoung;Lee, Eun-Heui
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.19 no.2
    • /
    • pp.55-69
    • /
    • 2016
  • Significant efforts are being devoted in mitigating the urban heat island effect, and extensive green roofs are an option for mitigation. The purpose of this study was to compare the surface temperature, vegetation types, and plant species on an extensive green roof. Test beds were created in May 2015, and the surface temperature was monitored from June to August. The test beds comprised polyculture and monoculture. Polyculture was divided into three types, and monoculture comprised eight plant species. An extensive green roof is effective in reducing temperature by forming a shade and preventing sunlight from falling on the surface of buildings, which mitigates the urban heat island effect. Consequently, the surface temperature of the green roof and that of concrete during summer reduced from $17.8^{\circ}C$ to $7.3^{\circ}C$. The temperature reduction was greater on using polyculture than on using monoculture, but monocultures of Sedum takesimense, Hemerocallis dumortieri, Allium senescens, Aster yomena, Belamcanda chinensis, and Aster koraiensis also produced good results. The temperature reduction effects of Polygonatum odoratum var. pluriflorum f. variegatum, Phlox subulata, and Thymus quinquecostatus var. japonica were excellent compared with those of concrete but were less than those of other plant species. Careful attention is needed for the management of extensive green roofs. Studies on the plant species and types of extensive green roof should continue to mitigate the urban heat island effect.

A Study on Test Methods for Performance Appraisal of Root Barrier Appling to Green Roofs (옥상 및 인공지반녹화용 방근재의 성능기준 설정을 위한 방근성 시험방법에 관한 연구)

  • Oh, Sang-Keun;Kwak, Kyu-Sung;Sun, Yoon-Suk;Kwon, Shi-Won
    • Journal of the Korea Institute of Building Construction
    • /
    • v.7 no.1 s.23
    • /
    • pp.79-84
    • /
    • 2007
  • Selection of proper root barrier as destination part of greening is very important in Root penetration resistance plan. To select proper root barrier, it need to understand composition of greening part, size, kind of plant, connection with waterproofing layer. In this point of view, we have establish greening on the roof or concrete structure, not been understand the structural mechanism. It means that we misunderstood about purpose of greening and using it. So, chosen materials and construction method was not proper for greening, it caused water leakage and decrease performance of concrete structure. Therefore, we would suggest 5 items of test methods considering environmental condition for green roof. Watertightness by water of greening part, root penetration resistance test by root penetration, bacteria resistance by must or bacteria in soil, chemical resistance by rain and chemical agent of fertilizer, and load resistance by soil depth, size of plant. These suggested test methods could be referred as guideline to test in green roof system because of not exist any performance appraisal guideline or standard. Consequently, it should be analysis as technical and institutional subdividing test methods and it need to study constantly as varied angles.

Analysis on the characteristics of the earth pressure distribution induced by the integrated steel pipe-roof construction (일체형 강관 파이프루프 시공에 따른 주변 지반의 토압 분포 특성 분석)

  • Sim, Youngjong;Jin, Kyu-Nam;Song, Ki-Il
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.15 no.5
    • /
    • pp.455-468
    • /
    • 2013
  • In recent, various types of steel pipe-roof methods, which is reinforced by mortar after propulsion of steel pipe into the ground, have been used for the construction of trenchless underpass. Integrated steel pipe-roof has flexural stiffness and can resist against overburden load and reduce the stress acting on the concrete underpass structures. Due to arching effect, vertical and horizontal stress distribution around the steel pipe-roof is changing. In this study, therefore, the characteristic of stress distribution around the underpass induced by the construction of integrated steel pipe-roof is investigated by using numerical method. To examine the soil-structure interaction, interface element is introduced. Results show that vertical stress acting on the concrete structure placing inside the steel pipe-roof is significantly reduced due to arching effect and flexural stiffness of integrated steel pipe-roof. Design load can be reduced and effective design of underpass will be available if the earth pressure reduction due to arching effect is considered in the design stage.

The Effect of Green Roof Load on the Structural Design of Roof Slab of LH Housing and Service Facilities (옥상녹화하중이 LH 공동주택 및 부대복리시설의 옥상층 슬래브 설계에 미치는 영향)

  • Lee, Bum-Sik;Kwon, Hyuck-Sam;Kim, Jung-Gon;Kim, Ji-Hyeon
    • Land and Housing Review
    • /
    • v.7 no.1
    • /
    • pp.53-63
    • /
    • 2016
  • This paper contains structural analysis and design regarding how three types of green roof load affect roof slab design of LH housing and facilities. Based on the Structural analysis, an appropriate Roof slab rebar guideline and roof slab thickness have been set up for the green roof load which takes effect on structural design of roof slab. Result of structural analysis and design has been made as follows. Roof slabs can arrange the slab rebar(D10) within the 200~250mm disregarding the types of the green roof load and the pattern of green roof load; also, slab thickness can be designed within 150mm. Moreover, even if the concrete design strength of roof slab changes to 24, 27, and 30MPa, D10 rebar can still be arranged within 200~250mm, and 150mm for slab thickness. Two-way slab of commercial building was appeared to be arranged by slab rebar(D10) within 200mm and 150mm for slab thickness disregarding the soil type or the soil thickness of green roof.

A Study on the Architectural Characteristics of Modern Railway Station in Gyeongju (경주관내 근대 철도역사(鐵道驛舍)의 건축적 특성에 관한 연구)

  • Choi, Moo-Hyun
    • Journal of the Korean Institute of Rural Architecture
    • /
    • v.14 no.3
    • /
    • pp.109-119
    • /
    • 2012
  • This study aims to analyze architectural characteristics of railway station facilities which were built with development of railroads from Japanese Colonial Period to 1950's. To achieve this goals, 7 railway stations in Gyeongju area that are worth preserving were set up as research targets. For this study, I analyzed literature of the railway station and drawings which the KORAL Daegu Branch is keeping. Railway stations without a construction drawing investigated a direct visit. After analyzing the railway station facilities, the architectural properties such as plan, elevation and section have been identified. The results are as follows. First, Each modern railway station is usually consisted of waiting room and office, and ancillary spaces have been added. Over the years, however, the space was expanded horizontally. In that case, the structure and finish materials have been changed, like now. Second, Most of the roof shape is 'Matbae'(gable roof), especially Gyeongju station and Bulguksa Station are 'Woojingak roof. The roof structure is truss structure, especially as Pratt and Scissors type, but Gyeongju Station's structure is a reinforced concrete. Third, main doorway of waiting room is located in the center of the front gable. However, small stations like 'Ahwa' and 'Ipsil' station to ensure the passengers' waiting area are placed next to the office area.

A Standard Test Methods of Resistance to Root Penetration for Waterproofing and Rootproofing Membrane Using Green Roof System (인공지반녹화용 멤브레인 방수 및 방근재료의 방근성능 평가 방법 제안 연구)

  • Lee, Jung-Hoon;Seon, Yun-Suk;Kwak, Kyu Sung;Oh, Sang-Keu
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2009.11a
    • /
    • pp.141-148
    • /
    • 2009
  • The purpose of this paper is to propose a standard test methods of resistance to root penetration for waterproofing and rootproofing membrane using green roof system. Green roof system is considered to be an important subject in construction industry for green growth project. At the same time, we have to consider the counterplan for protection the damage of waterproofing layer and concrete substrate from the penetration of plant root. But many kinds of materials for protection from root penetration are using in construction field. But the performance of those materials is not clear, and there is not test methods for the evaluation of performance. So in this paper, based on the research results of 4 institutes during four years and foreign cases, we made a standard test methods of resistance to root penetration for waterproofing and rootproofing membrane using green roof system. This test method deals with about environmental condition of laboratory, experimental facilities, kinds of plant, specimen of test, management methods, evaluation duration and documents, etc.

  • PDF

Study on Improvement of Thermal Environment by Green Roof Systems on RC Building - utilization of solar insulating block and the grass - (옥상녹화에 따른 콘크리트 건축물의 열환경 개선효과 -일사차폐블록과 잔디를 대상으로-)

  • Park, Chanpil;Furukawa, Nobuhisa
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.7 no.1
    • /
    • pp.1-9
    • /
    • 2004
  • Caused on the excessive heat accumulation of concrete material, the indoor thermal environment of reinforced concrete building is so bad in Okinawa. As the interruption of solar radiation could be one of the methods to improve it, the purpose of this study is to find out the effect of adopting solar radiation interrupting materials -Solar insulating block, Grass, and both of them- for the improvement of thermal environment. As the result, it was found that grass on the solar insulating block which has an air layer obviously improved the indoor thermal environment of RC building which was applied to. And it was found that the systems have an effectuality on heat island phenomenon simultaneously. It could be proposed as a good system which improve the indoor thermal environment of the existent houses.

Change of the Moisture and Temperature in Planting Ground as Effected by Different Soil Thickness, Soil Mixture Ratios and Ground Cover Plants in the Green Roof System (옥상녹화에서 토심, 토양배합비 및 지피식물에 따른 식재지반 수분 및 온도변화)

  • Ju, Jin Hee;Yoon, Young Han
    • KIEAE Journal
    • /
    • v.10 no.3
    • /
    • pp.11-16
    • /
    • 2010
  • This paper has attempted to investigate the change in soil moisture volume and temperature of architecture by planting ground(soil thickness and soil mixture ratio) and ground cover plants(Sedum sarmentosum, Zoysia japonica, Chrysanthemum zawadskii) for middle region green roof system. For this, a test was conducted on the roof of Konkuk University building from April 2009 to October 2009. In terms of treatment, five types(SL, $P_7P_1L_2$, $P_6P_2L_2$, $P_5P_3L_2$, $P_4P_4L_2$) depending on soil mixture ratio and two types(15cm, 25cm) by soil depth were created. Results of soil moisture volume by soil mixture ratio in the 15cm soil thickness showed that the difference was significance between simple soil and mixture soil treatment, however, the statistical significance was not recognized according to soil mixture ratio. In case of 25cm soil thickness, soil moisture volume by soil mixture ratio was more higher 7Vol.%~10Vol.% in the mixture soil than simple soil treatment. In terms of districts planted ground cover plants, soil volume moisture differed among plants in the order Zoysia japonica 17.74 Vol.%$34.86^{\circ}C$, district non-planted $27.49^{\circ}C$, Sedum sarmentosum $25.11^{\circ}C$, Chrysanthemum zawadskii $23.08^{\circ}C$, Zoysia japonica $24.45^{\circ}C$ respectively So, concrete surface showed more higher $5^{\circ}C{\sim}15^{\circ}C$ than other things among the all the time. Result of inner temperature of the architecture and soil, it was measured inner of architecture $25.69^{\circ}C$, inner district non-planted $24.29^{\circ}C$, Chrysanthemum zawadskii $23.90^{\circ}C$, Zoysia japonica $24.02^{\circ}C$, Sedum sarmentosum $25.13^{\circ}C$, respectively.