In this study, the seismic performance and behavior characteristics of the upper truss structure of the large stadium are analyzed by nonlinear dynamic analysis. In the nonlinear dynamic analysis, the earthquake records were generated by site response analysis to simulate the nonlinear behavior of the relevant soil condition where the structure is located. Nonlinear dynamic analysis was performed using Perform-3D and the nonlinear properties of the substructure and the superstructure were determined in accordance with KISTEC guideline. According to the analysis results, excessive deformation occurred in the upper truss element, and plastic hinges exceeded the target performance in some members. Buckling-restrained brace is used for seismic retrofit of stadium structures and the analysis results shows the interstory drift satisfies the target performance level with dissipating the seismic energy efficiently.

Seismic isolation systems have typically been used in the form of base seams in mid-rise and low-rise buildings. In the case of high-rise buildings, it is difficult to apply the base isolation. In this study, the seismic response was analyzed by changing the installation position of the seismic isolation device in 3D high - rise model. To do this, we used 30-story and 40-story 3D buildings as example structures. Historic earthquakes such as Mexico (1985), Northridge (1994) and Rome Frieta (1989) were applied as earthquake loads. The installation position of the isolation device was changed from floor to floor to floor. The maximum deformation of the seismic isolation system was analyzed and the maximum interlaminar strain and maximum absolute acceleration were analyzed by comparing the LB model with seismic isolation device and the Fixed model, which is the base model without seismic isolation device. If an isolation device is installed on the lower layer, it is most effective in response reduction, but since the structure may become unstable, it is effective to apply it to an effective high-level part. Therefore, engineers must consider both structural efficiency and safety when designing a mid-level isolation system for high-rise buildings.

레인가든과 저류지공원은 유역내의 도심공간에서 효율적인 빗물의 저류 및 관리를 위한 분산식 빗물관리 기법으로 지하수 확보나 비점오염원(NPPS)의 침투.여과를 통한 수질 정화, 폭우시 첨두유량의 감소위한 홍수터 복원 등의 기능을 가지며, 특히 저류지공원은 소생물서식공간 (biotope)을 기반으로 하는 가든형태의 생태공원으로 도시민에게 휴식과 여가, 교육 등 문화서비스의 장을 제공할 뿐만 아니라 도시의 미기후를 조절하는 순기능을 담당한다. 대상지인 효자2가 일대의 4.5택지는 전주 서부지역의 개발사업의 일환으로 조성된 1종 근린지역으로 관공서, 학교, 종교시설과 단독주택(근린, 준주거), 아파트, 어린이공원 등으로 조성되어 있다. 택지내의 용호근린공원은 농업용 저류지였던 용호지를 활용한 친수형 근린공원으로 전주시 완산구 효자동 2가 1333-2 일대에 소재하고, 면적은 31,330 ㎡ (약 9,477py)이며, 경계는 도심을 횡단하는 대로(홍산로)와 지천(중복천), 한국토지주택공사(LH) 전북지역본부와 인접한다. 현재 공원은 과거의 저수지를 일부 매립하고 나머지 수역을 유역 내의 우수를 취합하여 하천으로 방류하는 빗물저류지 공원으로 활용하고 있지만, 기후변화와 효자 4택지와 5택지를 포함한 도심지역의 녹지면적의 감소와 붙투수면적의 증가로 집수되는 우수의 양이 미약하여 저류지는 침전물로 인해 육화(陸化)되어 방재기능뿐만 아니라 공원으로서의 경관기능도 이미 상실하고 있는 실정이다. 또한 공원 내의 식생은 기존 수종과 자연 발생 수종들이 혼재되어 관리에 어려움이 있고, 인근한 대로와 경계를 이루는 식재가 부족하여 시.청각적 차폐가 이루어지지 못하고 있으며, 불투수층의 보행공간과 이용자가 없는 광장이나 여가시설, 친수나 생태교육을 위한 내용의 부재로 원래 목적이었던 생태공간이라고 하기에는 문제점이 있다. 본 연구는 저류지공원의 수량 확보와 수질 개선을 위해 배후가 되는 효자택지 내의 대,중.소규모 부지에 저영향개발(LID)의 일환인 레인가든의 Prototype의 제안을 기반으로 하고, 도시공원을 주제성을 가지는 저류지 생태공원으로 리모델링하는 설계이다. 세부 목적은 지속가능한 빗물관리 (sustainable water circulation), 도시와 공원의 연계강화 (interface & interactive), 종복원을 통한 생물다양성의 확보(biodiversity), 생태교육의 장(Eco program & education), 사회적 약자를 위한 동선체계(barrier-free circulation), 유 지관리를 위한 최소에너지와 비용(sustainable maintenance & management), 주민참여(participation & ritual) 등이다. 연구의 내용은 유역에 포함되는 효자 4택지와 5택지 일부와 용호근린공원을 범위로 정하고, 지역 내에 위치한 초. 중.고등학교와 관공서, 종교시설, 아파트(중규모)에 적용될 수 있는 투수성 주차장, 놀이터, 식생수로(green swale), 빗물정원, 수경시설 조성을 제안하고, 단독주택(소규모)에서는 옥상녹화, 벽면녹화, 건물주변에 지붕과 연결되는 빗물 저류 식생대 조성과 플랜터를 설치하는 일이다. 중점공간인 저류지공원(대규모)에서는 종복원을 위한 핵심(core)_완충 (buffering)_전이(transition)의 구간을 설정하며, 핵심지역은 저류지 중심부의 개방수역과 습지역의 수량.수질확보에 중점을 두고, 완충지역은 이용되지 않고 있는 불투수층의 광장이나 놀이광장을 레인가든으로 조성하여 다단계 cell의 역할로 핵심지역의 수질과 수량을 보완하는 기능을 한다. 그리고 전이지역은 인근한 대로와 이전에 조성된 동산과의 연계를 위하여 레인가든 조성시의 흙으로 적절한 높이의 지형을 만들고 식재를 보완하여 소음차단과 시각적 차폐를 유도한다. 저류지 공원의 핵심이 되는 개방수면을 위한 유량 확보와 수질 개선이 필수적이며, 대안으로 인근한 공공건물인 L.H 전북지역본부와 전북도교육청의 불투수면을 오픈시키는 적극적인 빗물관리와 중수(gray water)의 재활용, 유역 내 배후지의 적극적인 이용도 검토가 필요하다. 또한 복원종의 선정과 이를 위한 식재, 레인가든이나 저류지공원의 습생식물(water_loved plants), 수생식물(Hydrophytic plants), 침수식물(submerged plant), 부유식물(floating plants), 부엽 식물(rooted floating plants), 정수식물(emergent plants) 등의 선택과 토착화 또한 깊이 살펴야 할 과제이다. 연구의 과정은 이론검토, 관련법규의 검토, 국내외 레인 가든과 저류지공원 조성사례 조사분석 및 문제점 도출, 대상지의 분석과 문제점 파악(자연, 인문, 시각 환경분석), 개 념구상(레인가든과 저류지공원), 기본계획과 설계(레인가 든 유형과 저류지공원 zoning의 구체화), 저류지 공원의 Master Plan 작성(on.off site & section drawing), 설계 후의 고찰과 제언이다.

Vertical earthquake motions can occur along with horizontal earthquakes, so that Structure should be designed to resist Seismic loads in all directions. Especially, due to the dynamic characteristics such as the vibration mode, when the vertical seismic load, the dynamic response of the Spatial structure is large. In this study, the seismic response of the lattice dome to horizontal and vertical seismic loads is analyzed, and a reasonable seismic load combination is analyzed by combining horizontal and vertical seismic response results. In the combination of the horizontal seismic load, the largest result is obtained when the direction of the main axis of the structure coincides with the direction of seismic load. In addition, the combination of vertical seismic load and horizontal seismic load was the largest compared with the combination of horizontal seismic load. Therefore, it is considered that the most reasonable and stable design will be achieved if the seismic load in vertical direction is considered.

A base isolation system is widely used to reduce seismic responses of low-rise buildings. This system cannot be effectively applied to high-rise buildings because the initial stiffness of the high-rise building with the base isolation system maintains almost the same as the building without the base isolation system to set the yield shear force of the base isolation system larger than the design wind load. To solve this problem, the mid-story isolation system was proposed and applied to many buildings. The mid-story isolation system has two major objectives; first to reduce peak story drift and second to reduce peak drift of the isolation story. Usually, these two objectives are in conflict. In this study, a hybrid mid-story isolation system for a tall building is proposed. A MR (magnetorheological) damper was used to develop the hybrid mid-story isolation system. An existing building with mid-story isolation system, that is “Shiodome Sumitomo Building” a high rise building having a large atrium in the lower levels, was used for control performance evaluation of the hybrid mid-story isolation system. Fuzzy logic controller and genetic algorithm were used to develop the control algorithm for the hybrid mid-story isolation system. It can be seen from analytical results that the hybrid mid-story isolation system can provide better control performance than the ordinary mid-story isolation system and the design process developed in this study is useful for preliminary design of the hybrid mid-story isolation system for a tall building.

This paper presents the design, analysis, and experimental evaluations of precast reinforced UHPC (ultra high-performance concrete) beams with a new design concept of non-uniform flexural members. With outstanding mechanical properties of UHPC which can develop the compressive strength up to 200MPa, the tensile strengths up to 8~20MPa and the tensile strain up to 1~5%, a non-uniform structural shape of UHPC flexural beams were optimally designed using three-dimensional finite element analysis. The experiments were carried out and compared with the design strength in order to verify the performance of them. Proposed non-uniform UHPC beams were evaluated by a series of three-point beam loading test as well as estimated by design bending and shear strength of members. The newly designed UHPC beams show excellent performances not only in transverse load capacities but also in deformation capacities.

In this study, TMD(Tuned Mass Damper) is installed in a retractable-roof spatial structure in order to investigate dynamic response characteristics according to mass ratio and installed position of TMD on large spatial structures. The example analytical model is generated based on the Singapore sports hub stadium. Twenty eight analytical models are used to investigate optimal installation position of TMD for the example retractable-roof spatial structure using 4 to 16 TMDs. The mass of one TMD is set up 1% of total mass at the example analytical model. Displacement response ratio of model with TMD is compared with that of base model without TMD. It has been found from numerical simulation that it is more effective to install TMD at the edge of the spatial structure rather than to concentrate the TMD at the center of the spatial structure.

The outrigger damper system is a structural system with excellent lateral resistance when a wind load occurs. However, research on outrigger dampers is still in its infancy. In this study, dynamic response control performance of damper is analyzed according to change of stiffness value and damping value of damper. To do this, a real-scale 3D model of 50 stories has been developed and the artificial wind load has been entered for dynamic analysis. Generally, the larger the damping value, the smaller the stiffness value is, the more effective it is to reduce the maximum displacement and acceleration response. However, the larger the attenuation value as the cost of construction increases, it is necessary to select appropriate stiffness and damping value when applying an outrigger damper.

This study investigated a bio-tensegrity structural system that combines the characteristics of a general tensegrity structural system with a biological system. The final research objective is to accomplish a changeability for the structural system as like the movement of the natural bio-system. In the study, we present a shape finding procedure for the two stage bio-tensegrity system model inspired by the movement pattern of animal backbone. The proposed system is allowing a dynamic movement by introducing the concept of “saddle” for the variable bio-tensegrity structure. Several shape finding analysis example and results are presented and shows a efficient validation and suitability.

As the number of high-rise buildings increases, a mid-story isolation system has been proposed for high-rise buildings. Due to structural problems, an appropriate isolation layer displacement is required for an isolation system. In this study, the mid-story isolation system was designed and the seismic response of the structure was investigated by varying the yield strength and the horizontal stiffness of the seismic isolation system. To do this, a model with an isolation layer at the bottom of 15th floor of a 20-story building was used as an example structure. Kobe(1995) and Nihonkai-Chubu(1983) earthquake are used as earthquake excitations. The yield strength and the horizontal stiffness of the seismic isolation system were varied to determine the seismic displacement and the story drift ratio of the structure. Based on the analytical results, as the yield strength and horizontal stiffness increase, the displacement of the isolation layer decreases. The story drift ratio decreases and then increases. The displacement of the isolation layer and the story drift ratio are inversely proportional. Increasing the displacement of the isolation layer to reduce the story drift ratio can cause the structure to become unstable. Therefore, an engineer should choose the appropriate yield strength and horizontal stiffness in consideration of the safety and efficiency of the structure when a mid-story isolation system for a high-rise building is designed.

In order to reduce the seismic response of the spatial structure, a seismic isolation system with sufficient flexibility is used. The natural period of structure with seismic isolation system got be long to avoid prominent period. In this study, The seismic response of the truss-arch structure, which is modeled in three types according to the rise-span ratio is analyzed on El-centro, Northridge and Artificial Earthquake and compared with the seismic response of the truss-arch structure with lead rubber bearing(LRB). When seismic load is applied to the truss arch with isolation system, the horizontal acceleration response of the truss arch is reduced and vertical seismic response is also reduced. The application of the seismic isolation system is effective in controlling the seismic response.

Sb-doped SnO2 (ATO) transparent conducting films are fabricated using horizontal ultrasonic spray pyrolysis deposition (HUSPD) to form uniform and compact film structures with homogeneously supplied precursor solution. To optimize the molar concentration and transparent conducting performance of the ATO films using HUSPD, we use precursor solutions of 0.15, 0.20, 0.25, and 0.30 M. As the molar concentration increases, the resultant ATO films exhibit more compact surface structures because of the larger crystallite sizes and higher ATO crystallinity because of the greater thickness from the accelerated growth of ATO. Thus, the ATO films prepared at 0.25 M have the best transparent conducting performance (12.60±0.21 Ω/□ sheet resistance and 80.83% optical transmittance) and the highest figure-of-merit value (9.44±0.17 × 10-3 Ω-1). The improvement in transparent conducting performance is attributed to the enhanced carrier concentration by the improved ATO crystallinity and Hall mobility with the compact surface structure and preferred (211) orientation, ascribed to the accelerated growth of ATO at the optimized molar concentration. Therefore, ATO films fabricated using HUSPD are transparent conducting film candidates for optoelectronic devices.

Uniform TiO2 blocking layers (BLs) are fabricated using ultrasonic spray pyrolysis deposition (USPD) method. To improve the photovoltaic performance of dye-sensitized solar cells (DSSCs), the BL thickness is controlled by using USPD times of 0, 20, 60, and 100 min, creating TiO2 BLs of 0, 40, 70, and 100 nm, respectively, in average thickness on fluorine-doped tin oxide (FTO) glass. Compared to the other samples, the DSSC containing the uniform TiO2 BL of 70 nm in thickness shows a superior power conversion efficiency of 7.58±0.20% because of the suppression of electron recombination by the effect of the optimized thickness. The performance improvement is mainly attributed to the increased open-circuit voltage (0.77±0.02 V) achieved by the increased Fermi energy levels of the working electrodes and the improved short-circuit current density (15.67±0.43 mA/cm2) by efficient electron transfer pathways. Therefore, optimized TiO2 BLs fabricated by USPD may allow performance improvements in DSSCs.

A smart tuned mass damper (TMD) was developed to provide better control performance than a passive TMD for reduction of earthquake induced-responses. Because a passive TMD was developed decades ago, optimal design methods for structural parameters of a TMD, such as damping constant and stiffness, have been developed already. However, studies of optimal design method for structural parameters of a smart TMD were little performed to date. Therefore, parameter studies of structural properties of a smart TMD were conducted in this paper to develop optimal design method of a smart TMD under seismic excitation. A retractable-roof spatial structure was used as an example structure. Because dynamic characteristics of a retractable-roof spatial structure is changed based on opened or closed roof condition, control performance of smart TMD under off-tuning was investigated. Because mass ratio of TMD and smart TMD mainly affect control performance, variation of control performance due to mass ratio was investigated. Parameter studies of structural properties of a smart TMD was performed to find optimal damping constant and stiffness and it was compared with the results of optimal passive TMD design method. The design process developed in this study is expected to be used for preliminary design of a smart TMD for a retractable-roof spatial structure.

Base isolation system is generally used for low-rise buildings. For high-rise buildings subjected to earthquake loads, a mid-story isolation system was proposed and applied to practical engineering. In this study, seismic responses of high-rise buildings considering the installation story of the mid-story isolation system were evaluated. To do this, the 20-story and 30-story building were used as example structures. Historical earthquakes such as Kobe (1995), Northridge (1994) and Loma Prieta (1989) earthquakes were employed applied as earthquake excitations. The installation location of the mid-story isolation system was changed from the bottom of the 1st floor to the bottom of the top floor. The seismic responses of the example building were investigated by changing the location of the isolation layer. Based on the analytical results, when the seismic isolation system is applied, story drift ratio and acceleration response are reduced compared to the case without the isolation system. When the isolation layer is located on the lower part of the building, it is most effective. However, in that case, the possibility that the structure is unstable increases. Therefore, an engineer should consider both structural efficiency and safety when a mid-story isolation system for a high-rise building is designed.

PURPOSES: This study develops eco-friendly asphalt reinforcement materials applicable to bridge deck pavement. The main purpose is to ensure highly reliable quality applicable to structures and the possibility of practical application. The main target of the study is to develop materials that are environmentally friendly and capable of improving performanceMETHODS: The application of double-reinforcement fiber improves the performance of the road pavement. 1. We use recycled film for application of sheet-typed reinforcement. 2. We use preprocessing fibers to reinforce the properties of composite pavement materials.RESULTS : The developed products may produce materials that fit the purpose of achieving stability and environmental friendliness. Sheettyped reinforcements use more than 50% recycled resin. The most important type of damage to the asphalt layer is deflection (plastic deformation). These products have a very high deflection resistance of not less than 6,000 cycles/mm. In addition, all performance is excellent. Thus, it will be easier to access the field in the future.CONCLUSIONS: Fiber-reinforced asphalt pavement showed excellent performance. Sheet-typed reinforcements containing 50% recycling resin produced good performance in terms of functionality as well as environmental friendliness. Thus, enhancing the field applicability will enhance the usability of the reinforcements.