With the trends of massiveness and complexity of construction, the main agents of construction have considered the various types of risk management strategies to minimize the loss caused by the risk factors from the nature of construction project, regional characteristics, and scale of construction. The risk management has been conducted, because the risk factors have exacerbated the condition of construction in terms of the level of productivity, quality of construction, atmosphere, and budget. Based on thε interests regarding risk factor management, the current study suggests the work breakdown structure-based process. Additionally, based on the work breakdown structure, the risk factors on constructions are identified and stratified depending on the level of salience of each risk factor. The purpose of result is to lead Korean Land Corporation understand and control the risk factors properly for the advanced construction process of Korean Land Corporation. Ultimately the current study contribute to advance of efficient risk management strategies by using ANP method, which identify and control the primary risk factos depending on the impact of the interaction and subordinate relationship between risk factors.
This study is analyzing a member kind after placing concrete, the location-based temperature record, and the strength development, by making insulation gang-form with application of polyurethane form to general gang-form for securing efficient concrete quality in the condition of cold weather. According to our experimental results, the member of general gang-form with curing in the same condition as the actual field didn’t drop to under 3˚C until before 24 hours in the early part, but fell to under 0˚c from 36 hours later because a large rise in temperature caused by hydration reaction didn't occur. On the other hand, in case of insulation gang-form, the temperature on the surface and the central part didn't go down to under 3˚C before 12 hours in the early part and didn't fall to under it even until 72 hours after it while the peak temperature went up to 12˚C. Thus, it could be known to definitely have excellent insulation effect compared to space heating curing, which is generally performed on the spot. In comparison with space heating curing whose error in curing temperature is big every field, it is judged to likely have great effect on improvement in concrete quality given the work construction in cold weather and on early demolding in a cast during winter.
Recently, a market of architecture is requiring buildings of long spanned structures as most buildings become taller and larger. For being long spanned structures, elements of buildings must be light. As an alternative proposal, various hollow-core slabs and flat plate salbs were developed and used frequently in the inside and outside of the country. But the study of the hollow-core slabs using deck plate and assembly of light weight is the first. In the present study, Flexural and vibration tests were performed on the hollow-core slabs using deck plate and assembly of light weight to investigate the flexural behavior and serviceability. Four test specimens were used for test parameters; one hollow-core slab with an assembly of light weight, and three hollow-core slabs with deck plate and an assembly of light weight. The test parameters also included amount of tension bar and existence of shear reinforcement. The test results showed that the hollow-core slabs with deck plate and an assembly of light weight had a crack of shear, so shear reinforcement must be conducted.
Heunginjimun as treasure No.1 is wooden structure of 2 story. This stucly presents an investigation on vibration characteristics of Heunginjimun in Seoul through ambient vibration test. The research team studied structural characteristics unlike general building and performed the test. Natural or environmental excitation as ambient vibration source is always present and hence the test implies a minimum interference with normal use of the structure. Natural frequencies, damping ratio and modes are identified and compared using two strategies, Frequency Domain Decomposition, Stochastic Subspace Identification techniques. The result shows that behavior and dynamic property of Heuninjimun.
Environmental lighting zone-setting has suggested regulatory standards according to the influence of artificial illumination on natural environment and human life. Then, it is necessary to check out the viability of environmental lighting zone division as it is limited to use-zone division. This study aims to suggest some problems, which occur when environmental lighting zone is set by use-zone only, by comparing and analyzing the artificial illumination luminance. In addition, this study aims to suggest basis for the environmental lighting zone-setting and eventually, more effective environmental lighting zone division.
This study fouces on the electricity generation of B1PV system in the super-tall buildings. To improve the efficiency of the B1PV system, solar irradiance and air temperature should be taken into consideration. This study does research on, one of two main parameters, the solar irracliance in the super high-rise buildings. According to the measurement of solar irracliance, it increased with altitude. It is, particularly, more obviously in the super-tall buildings than others. Subsequently, to make an accurate B1PV elecrticity generation prediction,it is necessary to anaiyze the solar irracliance distribution on the super-taII building's facade which is a prerequisite for optimal B1PV system design.
This study proposed simply design procedure of a single degree of freedom (SDOF) structure equipped with friction dampers. General method is suggested in order to reduce the structural seismic response by using friction dampers. The analysis model was transformed into an equivalent mass-spring-dashpot system by approximating nonlinear friction damping force with equivalent viscous damping force. A closed form solution for dynamic amplification factor (DAF) for steady-state response was derived by the energy balance equation. The equivalent damping ratio was defined by using DAF at natural frequency. The transfer function between input harmonic excitation and output structural response was obtained from the DAF, and the response reduction factor of the root mean square (RMS) for displacements without and with friction dampers was analytically determined. Using the proposed procedure the friction force required for satisfying given target response reduction factor was obtained. Mean response reduction factors matched well with the target values based on the dynamic analysis results. It is concluded that the proposed method is quite simple for the design of friction dampers to reduce seismic response of the structure.