In this study, the characteristics of wind pressure distribution on circular retractable dome roofs with a low rise-to-span ratio were analyzed under various approaching flow conditions by obtaining and analyzing wind pressures under three different turbulent boundary layers. Compared to the results of previous studies with a rise-to-span ratio of 0.1, it was confirmed that a lower rise-to-span ratio increases the reattachment length of the separated approaching flow, thereby increasing the influence of negative pressure. Additionally, it was found that wind pressures varied significantly according to the characteristics of the turbulence intensity. Based on these experimental results, a model for peak net pressure coefficients for cladding design was proposed, considering variations in turbulence intensity and height.

A timber lattice roof, which has around 30m span, was constructed. In order to figure out the realistic buckling load level, the structural analysis of this roof structure was performed especially by stiffness of connection with various asymmetric snow load. Due to the characteristics of application of snow load, the load combinations of snow should be considered not only global area but also local part so that the critical buckling load could be observed as easy as possible. Geometrical imperfection was simulated to consider inaccurate shape of structure. And then nonlinear analysis were performed. Finally, this paper could investigate that the asymmetric snow load with the lower level stiffness of connection decreased the level of buckling load significantly.

본 연구에서는 실대형 실험과 구조해석을 통해서 현장에서 사용되는 가새 시스템을 적용한 강관 골조 플라스틱 연동온실 의 횡하중 가력시험을 수행하고 성능을 분석하였다. 횡강성 과 응력을 분석하기 위해 실험체에 변위와 변형률계를 각각 9 개소 및 16개소 설치하였으며 가새의 설치 유무에 따른 성능 을 비교하기 위해 구조해석을 수행하였다. 실대형 실험과 가 새의 설치 유무에 따른 구조해석 결과 비교에서 구조물의 횡 강성이 많은 차이를 보였다. 실험체의 측고 부근에서 측정한 횡강성은 가새 시스템을 설치함으로 강성을 최대 44%까지 증 가시켰다. 현장에서 사용하는 가새의 접합부가 충분한 강성 을 확보하지 못함으로써 외력을 전체 구조물에 적절히 전달하 지 못하여 횡강성이 구조해석 결과보다 많이 저하되는 현상이 나타났다. 따라서 온실 설계 시 구조성능의 신뢰성을 높이기 위해서 가새 시스템의 연결방법, 설치위치, 부재의 최대길이 등 온실의 접합부에 대한 명확한 시공방법과 설계기준이 정립 되어 온실 설계가 이루어져야 할 것으로 판단된다.

San-ja is one of the main members consisting of the roof of traditional wooden buildings in Korea. In this study, the regional characteristics of the materials used in San-ja and changes of the materials over time were examined. To this end, 123 documents on the repair of wooden architectural heritage recorded since the 1950s were reviewed. It was found that there was a difference in the San-ja material by region because of the diversity in the conditions of material supply. For instance, bamboo was the most frequently used material in Jeollanam-do province because it was readily available. However, with the development of transportation and vehicle, the regional characteristics have disappeared. As a result, the material has been unified with bamboo now. This is because bamboo is specified as a representative material in the specification or the convenience of construction is prioritized. In addition, the social and economic conditions at the time of repair had an influence on the selection of the San-ja materials.

In this study the characteristics of wind pressure that are depending on the open type of retractable dome roof were analyzed according to the wind pressure coefficient and wind pressure spectrum. The analysis results showed that the open type and shape of the roof both had a significant impact on the wind pressure changing. In case of the edge to center open type, the wind pressure has not changed much because of the complex turbulence of flow and open area. On the other hand, in case of the center to edge open type, it has confirmed that wind pressure increases due to the separation of flow in windward and open area.

The fluctuating wind pressure of the low rise ratio(f/D=0.1) for the elliptical dome roof was analyzed to compare it with the previous studies of circular dome roofs. Wind tunnel test were conducted on a total of 10 wind directions from 0° to 90° while changing wall height-span ratios(H/D=0.1-0.5). For this, meanCP, rmsCP and wind pressure spectrum were analyzed. The analysis result leads to find differences in the shape of the spectra in the spanwise direction and leeward of the elliptical dome according to the wind direction variations of the elliptical dome roof.

This study examines the optimum shape of a trolley, the driving device of the retractable membrane roof. The closed-type trolley was determined as the model of the study, and a trolley composed of cylindrical-shaped inner and outer holders was selected as the basic model. Based on this model, a cylindrical-based optimal trolley model was proposed. In the basic trolley model, steel was used for the outer holder, and steel, titanium, and aluminum were used for the inner holder. In each case, the most economical shape for the external load of the basic model was newly proposed through the topology optimization process, and the finite element analysis results of the proposed model were compared to define the durability and economics. Here, topology optimization analysis and finite element analysis used the commercial software ANSYS. As a result of optimization, the volume of the outer holder of the trolley was reduced by 58.2% and the volume of the inner holder was reduced by 25.0% compared to the basic model. In the case of stress, a stress increase of 43.2 to 79.2% occurred depending on the material of the inner holder, but it was found to be significantly lower than the yield strength, thereby ensuring safety.

Wind tunnel tests were conducted to analyze the wind fluctuating pressures on a circular closed and open dome roof with a low span rise. Two dome models with various geometric parameters (height/span ratios and open ratios) were used for fixed span rise ratio dome and wind pressure spectrum were analyzed. The applicability was examined in comparison with the spectral model proposed in the previous studies. The analysis results show that the wind pressure spectrum of open dome roof tends to increase power in the high frequency range and the second peak is found in the area different from the closed dome roof. In addition, according to the comparison analysis with the previous proposed spectral model, it was found that it is not applicable to the closed and open dome roofs with low rise ratio due to the different peak frequencies.

In this paper, the mean and fluctuating pressure coefficients derived from the results of wind tunnel tests on closed and open dome roofs were analyzed. The distribution characteristics of the fluctuating pressure according to the opening ratio and the height change were discussed. The analysis results showed that when the roof is open, the overall wind pressure decreases due to the open space, but more fluctuation occurred than the closed dome roof.

This study investigates the wind pressure characteristics of elliptical plan retractable dome roof. Wind tunnel experiments were performed on spherical dome roofs with varying wall height-span ratios (0.1~0.5) and opening ratios (0%, 10%, 30% and 50%), similar to previous studies of cirular dome roofs. In previous study, wind pressure coefficients for open dome roofs have been proposed since there are no wind load criteria for open roofs. However, in the case of Eeliptical plan retractable dome roof, the wind pressure coefficient may be largely different due to the presence of the longitudinal direction and transverse direction. The analysis results leads to the exceeding of maximum and minimum wind pressure coefficients KBC2016 code.

The cable-based retractable membrane roof makes it impossible to maintain its shape and stiffness during driving process, unlike the hard-type retractable roof. Consequently, monitoring using a relatively simple wireless video transmission device is required. However, since video data has a bigger transmission rating than other monitoring data in terms of the structure velocity or acceleration, there is a need to develop transmission device that is easy to install and entails low maintenance cost. This paper studies on a real-time video transmission system for monitoring the cable-based retractable membrane roof while driving. A video transfer software, using the mobile network, is designed and the embedded system is constructed. Ultimately, the data transmission server is tested. Connecting a trolley to the system allows testing of the validity and efficiency of the developed system through the video data transmitted in the driving process. Result of the test shows that the developed system enables multi-device data transfer with monitoring via the mobile network.