• Steel and Composite Structures
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• 제43권4호
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• pp.465-481
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• 2022

This paper presents a comprehensive integrity assessment of welded structural components, including uniform high- and low-cycle fatigue assessment of welded plate joints and fatigue-induced fracture assessment of welded plate joints. This study reports a series of fatigue and fracture tests of welded plate joints under three-point bending. To unify the assessment protocol for high- and low-cycle fatigue of welded plate joints, this study develops a numerical damage assessment framework for both high- and low-cycle fatigue. The calibrated damage material parameters are validated through the smooth coupon specimens. The proposed damage-based fatigue assessment approach describes, with reasonable accuracy, the total fatigue life of welded plate joints under high- and low-cycle fatigue actions. Subsequently, the study performs a tearing assessment on the ductile crack extension of the fatigue-induced crack. The tearing assessment diagram derives from the load-deformation curve of a single-edge notched bend, SE(B) specimen and successfully predicts the load-crack extension relation for the reported welded plate joints during the stable tearing process.

• 한국환경독성학회:학술대회논문집
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• 한국환경독성학회 2001년도 추계심포지움 및 학술발표회:환경오염의 생체지표를 이용한 위해성 평가의 최근 기법
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• pp.89-89
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• 2001

• Structural Engineering and Mechanics
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• 제32권2호
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• pp.301-320
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• 2009

Damage assessment for buried structures against an internal blast is conducted by considering the soil-structure interaction. The structural element under analysis is assumed to be rigid-plastic and simply-supported at both ends. Shear failure, bending failure and combined failure modes are included based on five possible transverse velocity profiles. The maximum deflections with respect to shear and bending failure are derived respectively by employing proper failure criteria of the structural element. Pressure-Impulse diagrams to assess damage of the buried structures are subsequently developed. Comparisons have been done to evaluate the influences of the soil-structure interaction and the shear-to-bending strength ratio of the structural element. A case study for a buried reinforced concrete structure has been conducted to show the applicability of the proposed damage assessment method.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 1999년도 Proceedings of International Symposium on Remote Sensing
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• pp.243-248
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• 1999

From the lessons after the Nakhodka oil-spill in Jan. 1997, oil slick detection by using remote sensing data and assimilating the data to the simulation program is important for monitoring the oil-drift pattern. For this object, we are going to construct the oil-spill warning system for estimating the oil-drift pattern using remotesensing/numerical simulation Model. Additionally we plan to use this system for restorating oil-spill damage domestically, such as estimating the ecological damage and making the priority fur restorating the oil-spilled shoreline. This report is intended to summarize the role of geo-informatics in the oil spill accident by not only paying attention to the effect of information provision/information management via the map, but also reporting the interim result in part based on the details discussed in the processes of recovery support and environmental impact assessment during the Nakhodka's accident.

• 한국환경복원기술학회지
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• 제23권6호
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• pp.15-28
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• 2020

Urbanization and industrialization have caused increasing damage to national lands, and ecological restoration has proceeded without any specific assessment of this damage. The purpose of this study is to select indices to assess damaged areas through literature review and panel discussions, and to derive the importance of damaged area assessment indices by analyzing them through the Analytic Hierarchy Process (AHP). This study has derived, via literature review, six types of damage and a total of 18 related assessment indices. A total of 51 responses were collected from surveys and given to experts, and an AHP analysis conducted. As a result of the analysis, "Landform change (0.268)" was of the highest importance, with associated damage types as follows: "Soil contamination (0.193)", "Vegetation damaged (0.149)", "Surface soil loss (0.143)", "Change in soil physiochemical property (0.125)", and "Vegetation decline (0.122)". The analysis determined that the item of the highest importance in the overall assessment of damage was "Slope occurred area (0.100)", and that "Conductivity (0.022)" was of the lowest importance. This study can be presented as a criterion in determining the type and degree of damage in setting priorities for future ecological restoration projects.

• 환경영향평가
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• 제20권2호
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• pp.141-150
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• 2011

The construction of photovoltaic complex in mountainous area is quickly increasing recently so that the environment assessment in constructing photovoltain complex in mountainous area was performed by comparison of $CO_{2{\cdot}}$ reduction and forest damage. The case studies for environmental value assessment, which construct photovoltaic complex in mountainous area, show that the losses of around 5.1billion won arise during 15 years. The government's official target for spreading photovoltaic energy until year 2030 can be satisfied when considering other alternative sites, improvement of technology and the alternative sites of an idle space of a building or a disused site, etc, except an undeveloped mountainous area. The construction of photovoltaic complex in mountainous area can cause the great damage to the environment, especially undeveloped mountainous area such as Baekdudaegan, and this defeat its own purpose of using photovoltaic energy. Therefore, the spread of photovoltaic complex through the additional damage of forest should be sublated.

• 환경영향평가
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• 제21권1호
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• pp.93-104
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• 2012

In this research LCA methodology was adapted and analyzed in quantifying estimation of estuarine environment. The analysed objects of estuarine environment were construction methods, facility, and input material into water, and estuarine ecosystem. In this research the function of LCA of estuarine environment was river with the view of controling water, utilizing water, and hydrophilic function. According to the result of research, environmental damage indicator of facility was decreased 346 Pt from 453 Pt at pre-maintenance to 107 pt at post-maintenance. Among raw and subsidiary materials, remicon, stone-netting bag, and pebbles were showing heavy environmental load in the order. Evironmental impact of input material into water system was analyzed from 1,827 Pt environmental load before construction to 1,080 Pt of post-maintenance, and damage indicator was improved at 747 Pt. Water quality was improved from 1,827 Pt (before construction) to 1,080 Pt(after construction), and ecosystem was improved after maintenance. Environmental indicator in ecosystem was analyzed 427 Pt(before construction) to 348 Pt(after construction), and damage indicator of Sumnjingang riverine system was improved as much as 79 Pt. In the conclusion, estuarine environmental monitoring through LCA in the area of facility, input material into water and ecosystem showed that close-to-nature stream was 1,172 Pt better than artificial stream in environmental aspects.

• 산업경영시스템학회지
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• 제24권68호
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• pp.51-65
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• 2001

This study is to make LCIA(Life Cycle Impact Assessment) easier as a methodology of environmental scores(called E-score) that integrated environmental load of each emission substance based on environmental damage such as in human health, ecosystem and resources category. The concept is to analyzes the LCI(Life Cycle Inventory) and defines the level of environment damages for human health, ecosystem and resources to objective impact assessment standard, and makes the base of marginal damage to calculate the damage factor, which can present the indication that can establish the standard value of environmental impact. First, damages to human health are calculated by fate analysis, effect analysis and damage analysis to get the damage factor of health effect as a DALY(Disability Adjusted Life Years) unit. Second, damages to ecosystem are calculated by fate analysis, effect analysis and damage analysis to get the damage factor of the effect as a PDF(Potentially Disappeared Fraction) unit through linking potentially increased disappeared fraction. Third, damages to resources are carried out by resource analysis and damage analysis for linking the lower fate to surplus energy conception to get damage factor as a MJ(Mega Joule) unit. For the ranking of relative environment load level each other, LCIA can be carried out effectively by applying this E-score methodology to the particular emission substances. A case study has been introduced for the emission substances coming out of a tire manufacturer in Korea. It is to show how to work the methodology. Based on such study result, product-designers or producers now can apply the E-scores presented in this study to the substances of emission list, and then calculate the environment load of the product or process in advance at any time and can see the environment performance comparatively and expected to contribute to the environmental improvement in view of environmental pollution prevention.

• 한국지진공학회논문집
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• 제22권3호
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• pp.121-128
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• 2018

Severe earthquakes can cause damage to society both socially and economically. An appropriate initial response can alleviate damage from severe earthquakes. In order to formulate an appropriate initial response, it is necessary to identify damage situations in societies; however, it is difficult to grasp this information immediately after an earthquake event. In this study, an earthquake damage assessment methodology for buildings is proposed for estimating damage situations immediately after severe earthquakes. A response spectrum database is constructed to provide response spectra at arbitrary locations from earthquake measurements immediately after the event. The fragility curves are used to estimate the damage of the buildings. Earthquake damage assessment is performed from the response spectrum database at the building scale to provide enhanced damage condition information. Earthquake damage assessment for Gyeongju city and Pohang city were conducted using the proposed methodology, when an earthquake occurred on September 12, 2016, and November 15, 2017. Results confirm that the proposed earthquake damage assessment effectively represented the earthquake damage situation in the city to decide on an appropriate initial response by providing detailed information at the building scale.

• Structural Monitoring and Maintenance
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• 제2권3호
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• pp.269-282
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• 2015

Civil structures should be designed with the lowest cost and longest lifetime possible and without service failure. The efficient and sustainable use of materials in building design and construction has always been at the forefront for civil engineers and environmentalists. Timber is one of the best contenders for these purposes particularly in terms of aesthetics; fire protection; strength-to-weight ratio; acoustic properties and seismic resistance. In recent years, timber has been used in commercial and taller buildings due to these significant advantages. It should be noted that, since the launch of the modern building standards and codes, a number of different structural systems have been developed to stabilise steel or concrete multistorey buildings, however, structural analysis of high-rise and multi-storey timber frame buildings subjected to lateral loads has not yet been fully understood. Additionally, timber degradation can occur as a result of biological decay of the elements and overloading that can result in structural damage. In such structures, the deficient members and joints require strengthening in order to satisfy new code requirements; determine acceptable level of safety; and avoid brittle failure following earthquake actions. This paper investigates performance assessment and damage assessment of older multi-storey timber buildings. One approach is to retrofit the beams in order to increase the ductility of the frame. Experimental studies indicate that Sprayed Fibre Reinforced Polymer (SFRP) repairing/retrofitting not only updates the integrity of the joint, but also increases its strength; stiffness; and ductility in such a way that the joint remains elastic. Non-linear finite element analysis ('pushover') is carried out to study the behaviour of the structure subjected to simulated gravity and lateral loads. A new global index is re-assessed for damage assessment of the plain and SFRP-retrofitted frames using capacity curves obtained from pushover analysis. This study shows that the proposed method is suitable for structural damage assessment of aged timber buildings. Also SFRP retrofitting can potentially improve the performance and load carrying capacity of the structure.