• 한국전산구조공학회논문집
• /
• 제28권2호
• /
• pp.177-185
• /
• 2015

도시기반 라이프라인은 지진발생시 시설물의 붕괴뿐만 아니라 붕괴로 인한 도시기능 마비, 대형화재와 같은 2차 피해를 동반하여 막대한 사회 경제적 손실을 야기할 것으로 예측된다. 이에 대한 대비책으로 국내에서는 지진재해대응시스템을 운영 중이며, 지진재해대응시스템은 각 시설물별 지진취약도 모델을 통해서 시설물의 파괴확률을 산정하고, 지진재해 정도를 평가한다. 따라서 본 논문에서는 국내 지반특성을 고려하여 도시기반 라이프라인 시설물 중 매설가스배관의 시간이력 해석을 수행하였고, 확률론적인 해석방법인 최우도추정법을 이용하여 지진취약도 모델을 개발하였다. 해석모델은 국내 대표도시인 서울지역에 매설된 고압관과 중압관으로 선정하였으며, 지반의 모델링은 Winkler foundation 모델을 이용하였다. 또한 개발된 취약도 모델의 GIS 적용방안을 제시하였다.

• 한국지반신소재학회논문집
• /
• 제15권4호
• /
• pp.9-16
• /
• 2016

2004년 일본의 니가타켄 츄에츠 지방의 나가오카, 오지야시에서 1,450개 이상의 지하구조물이 1.5m까지 부상하였다. 융기손상은 Lifeline 시스템의 일부인 하수 시스템의 흐름뿐만 아니라 교통흐름을 방해로 인해 심각한 문제를 야기 시킨다. 복구작업의 경우 손상된 하수 시스템의 오픈 컷 조사는 나가오카시 정부에 의해 수행되었다. 지진으로 인한 매설된 파이프 라인의 손상에 대한 중요한 데이터는 조사결과로부터 수집하였다. 본 연구는 지하 구조물의 부상량에 영향을 미치는 요인을 SPT 시추공 logs를 통해 손상된 지역의 위치와 파이프라인의 경사를 포함하는 데이터를 사용하여 조사하였다. 지하구조물의 부상과 영향을 받는 지역의 지질학적 특성 사이의 상관관계 분석을 통해 부상현상의 주요변수는 지하수의 깊이, 원지반에서의 점토층 두께, SPT N값인 것으로 밝혔다.

• Smart Structures and Systems
• /
• 제24권1호
• /
• pp.1-14
• /
• 2019

Transmission tower-line system is one of most critical lifeline systems to cities. However, it is found that the transmission tower-line system is prone to be damaged by earthquakes in past decades. To mitigate seismic demands, this study introduces a tuned-mass damper (TMD) using superelastic shape memory alloy (SMA) spring for the system. In addition, considering the dynamic characteristics of both tower-line system and SMA are affected by temperature change. Particular attention is paid on the effect of temperature variation on seismic behavior. In doing so, the SMA-TMD is installed into the system, and its properties are optimized through parametric analyses. The considered temperature range is from -40 to $40^{\circ}C$. The seismic control effect of using SMA-TMD is investigated under the considered temperatures. Interested seismic performance indices include peak displacement and peak acceleration at the tower top and the height-wise deformation. Parametric analyses on seismic intensity and frequency ratio were carried out as well. This study indicates that the nonlinear behavior of SMA-TMD is critical to the control effect, and proper tuning before application is advisable. Seismic demand mitigation is always achieved in this wide temperature range, and the control effect is increased at high temperatures.

• 한국지진공학회:학술대회논문집
• /
• 한국지진공학회 2000년도 춘계 학술발표회 논문집 Proceedings of EESK Conference-Spring
• /
• pp.89-96
• /
• 2000

Landslide damage comprise most part of the damages from the earthquake and it only causes the damage to lives and structures directly but also cease the operation of social system by road or lifeline failure. For these reasons hazard assesment on the landslides has been recognized very important. And hazard maps have been used to visualize the hazard of the landslide. In this study as first step for application of hazard map to domestic cases hazard maps are made for the Ul-Joo Ul-san Korea, Where the Yan-san faults are located. For building hazard maps the degree of hazard are evaluated based on Newmark displacement and the resulting maps are constructed by GIS technique. In hazard assesment maximum ground acceleration obtained from attenuation equation of wave propagation and design earthquake acceleration suggested by Ministry of construction are used for acceleration term. Hazard maps are made by GIS programs Arc/Info and Arc/View based on the digital maps and data from lab tests and elastic wave surveys The maps show the possible landslide regions significantly and the displacements of slide are proportional to the slope angles.

• Asian Journal of Innovation and Policy
• /
• 제4권2호
• /
• pp.154-177
• /
• 2015

India faces a formidable challenge in ensuring security of access to modern energy carriers to majority of its population. The fossil-fuel dominated centralized energy system has proved to be ineffective in creating sustainable access to energy, which suggests need for a radical and innovative approach. We present such an approach. First, the need for innovations given the implications of lack of energy access on sustainable development is assessed. Next, possible innovations with respect to technologies, policies, institutions, markets, financial instruments and business models are discussed. Finally, an economic and financial feasibility of implementing such innovations are analyzed. The results indicate that such a proposal needs an investment of US$ 26.2 billion over a period of 20 years for a GHG mitigation potential of 213Tg $CO_{2e}$. The proposition is profitable for the enterprises with IRRs in the range of 39%-66%. The households will get lifeline access to electricity and gas for cooking at an affordable monthly cost of about US$ 5.7.

• 한국방재학회:학술대회논문집
• /
• 한국방재학회 2009년도 정기 학술발표대회
• /
• pp.13-24
• /
• 2009

This paper introduces various kinds of applications of the scenario-based seismic risk assessment in Taiwan. Seismic scenario simulation (SSS) is a GIS-based technique to assess distribution of ground shaking intensity, soil liquefaction probability, building damages and associated casualties, interruption of lifeline systems, economic losses, etc. given source parameters of an earthquake. The SSS may integrate with rapid earthquake information release system to obtain valuable information and to assist in decision-making processes to dispatch rescue and medical resources efficiently. The SSS may also integrate with probabilistic seismic hazard analysis to evaluate various kinds of risk estimates, such as average annual loss and probable maximum loss in one event, in a probabilistic sense and to help proposing feasible countermeasures.

• 한국지진공학회:학술대회논문집
• /
• 한국지진공학회 1998년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Spring 1998
• /
• pp.369-376
• /
• 1998

The purpose of the present study is to analyze the response of pipelines subjected to liquefaction-induced permanent ground displacement and to discuss the failure prediction of domestic waterway pipelines. Initially here, characteristics of liquefaction are reviewed and then permanent ground displacement is investigated base on previous earthquake hazard cases. Next, considering the distribution of the transverse permanent ground displacement and equivalent spring constant effect, formulas obtained by a beam theory are established to analyze continuous pipelines. This analysis was performed without consideration of axial effects. So the finite element analysis was used in order to consider the axial stiffness of soil. As a result, degree of liquefaction, width of deformed ground and axial stiffness are crucial points for evaluation the failure of pipelines subjected to permanent ground displacement.

• 한국지진공학회:학술대회논문집
• /
• 한국지진공학회 1999년도 춘계 학술발표회 논문집 Proceedings of EESK Conference-Spring
• /
• pp.109-118
• /
• 1999

Lifeline system such as oil or gas pipelines and water supply facilities are vulneratble to seismic damages because they are widely exposed to ground failures. Most seismic design criteria of buried pipelines are based on the notion that the longitudinal compressive strain and therefore buckling controls the design. Buckling analysis of buried pipelines subjected to seismic loading is performed by considering the seismic load as the sinusoidally distributed compressive load on the beam on elastic foundation in contrast to existing studies where the buckling load is treated as an end load on the beam column, An approximated analytical solution is obtained by the energy method and its validity is confirmed by the linearized finite element buckling analysis. The results show the beam mode buckling because longitudinal strains at the buckling loads are substantially lower than the strain at the onset of local buckling.

• Smart Structures and Systems
• /
• 제6권3호
• /
• pp.309-333
• /
• 2010

Civil infrastructure, in both its construction and maintenance, represents the largest societal investment in this country, outside of the health care industry. Despite being the lifeline of US commerce, civil infrastructure has scarcely benefited from the latest sensor technological advances. Our future should focus on harnessing these technologies to enhance the robustness, longevity and economic viability of this vast, societal investment, in light of inherent uncertainties and their exposure to service and even extreme loadings. One of the principal means of insuring the robustness and longevity of infrastructure is to strategically deploy smart sensors in them. Therefore, the objective is to develop novel, durable, smart sensors that are especially applicable to major infrastructure and the facilities to validate their reliability and long-term functionality. In some cases, this implies the development of new sensing elements themselves, while in other cases involves innovative packaging and use of existing sensor technologies. In either case, a parallel focus will be the integration and networking of these smart sensing elements for reliable data acquisition, transmission, and fusion, within a decision-making framework targeting efficient management and maintenance of infrastructure systems. In this paper, prudent and viable sensor and health monitoring technologies have been developed and used in several large structural systems. Discussion will also include several practical bridge health monitoring applications including their design, construction, and operation of the systems.

• Smart Structures and Systems
• /
• 제32권1호
• /
• pp.49-59
• /
• 2023

A bridge transportation network supplies products from various source nodes to destination nodes through bridge structures in a target region. However, recent frequent earthquakes have caused damage to bridge structures, resulting in extreme direct damage to the target area as well as indirect damage to other lifeline structures. Therefore, in this study, a surrogate model-based comprehensive framework to estimate the seismic resilience of bridge transportation networks is proposed. For this purpose, total system travel time (TSTT) is introduced for accurate performance indicator of the bridge transportation network, and an artificial neural network (ANN)-based surrogate model is constructed to reduce traffic analysis time for high-dimensional TSTT computation. The proposed framework includes procedures for constructing an ANN-based surrogate model to accelerate network performance computation, as well as conventional procedures such as direct Monte Carlo simulation (MCS) calculation and bridge restoration calculation. To demonstrate the proposed framework, Pohang bridge transportation network is reconstructed based on geographic information system (GIS) data, and an ANN model is constructed with the damage states of the transportation network and TSTT using the representative earthquake epicenter in the target area. For obtaining the seismic resilience curve of the Pohang region, five epicenters are considered, with earthquake magnitudes 6.0 to 8.0, and the direct and indirect damages of the bridge transportation network are evaluated. Thus, it is concluded that the proposed surrogate model-based framework can efficiently evaluate the seismic resilience of a high-dimensional bridge transportation network, and also it can be used for decision-making to minimize damage.