• Title/Summary/Keyword: earthquake disaster

Search Result 523, Processing Time 0.025 seconds

Analytical study of the verification of the performance improvement of the strengthening systems for the open cut tunnel (개착식터널의 내진성능보강 효과분석에 대한 해석적 연구)

  • Kim, Ki-Hong;Kwon, Min-Ho;Jang, Young-Do
    • Proceedings of the KSR Conference
    • /
    • 2011.05a
    • /
    • pp.456-461
    • /
    • 2011
  • Recently the design specification has been advanced with preventing earthquake disaster in Korea because of increasing occurrence of large size earthquake. A composite plate with ductile fiber is proposed, which can enhance the performance of built tunnel in both strength and ductility. This study is to focus to verify the effect of strengthening of existing tunnels which is built without earthquake type load scenario, so that it can provide the safety of existing urban subway system against earthquakes.

  • PDF

1D finite element artificial boundary method for layered half space site response from obliquely incident earthquake

  • Zhao, Mi;Yin, Houquan;Du, Xiuli;Liu, Jingbo;Liang, Lingyu
    • Earthquakes and Structures
    • /
    • v.9 no.1
    • /
    • pp.173-194
    • /
    • 2015
  • Site response analysis is an important topic in earthquake engineering. A time-domain numerical method called as one-dimensional (1D) finite element artificial boundary method is proposed to simulate the homogeneous plane elastic wave propagation in a layered half space subjected to the obliquely incident plane body wave. In this method, an exact artificial boundary condition combining the absorbing boundary condition with the inputting boundary condition is developed to model the wave absorption and input effects of the truncated half space under layer system. The spatially two-dimensional (2D) problem consisting of the layer system with the artificial boundary condition is transformed equivalently into a 1D one along the vertical direction according to Snell's law. The resulting 1D problem is solved by the finite element method with a new explicit time integration algorithm. The 1D finite element artificial boundary method is verified by analyzing two engineering sites in time domain and by comparing with the frequency-domain transfer matrix method with fast Fourier transform.

The research of u-disaster prevention City service and technology (u-방재 City 서비스 및 기술에 관한 연구)

  • Lee, Bum-Gyo;Kim, Hyun-Joo;Han, Jin-Woo
    • 한국정보통신설비학회:학술대회논문집
    • /
    • 2008.08a
    • /
    • pp.277-280
    • /
    • 2008
  • Starting from 2005, as the new city paradigm, the term 'u-City' was created in Korea. U-City service, as defined in "u-City law", is a service that connects and intermediates among government, traffic, welfare, environment, disaster mitigation, etc., and their data based on ubiquitous city technology and infrastructure. According to the survey executed by local governments, the improvements in the standard of living of citizens have in turn increased the needs for anti-mitigation services. Such trend is bolstered with the recent disasters such as the conflagration of Korean Soong-rae Gate and the devastating earthquake of Sichuan province. This article describes a concept of the u-City disaster prevention service and looks into the activities and planning of u-City disaster prevention service of local governments. This paper also briefly looks into the law and policies to derive the needs of u-City disaster prevention service as well as the current technologies and u-City disaster prevention services of local governments. Ultimately, this paper offers the strategic direction of developing u-Disaster Prevention City.

  • PDF

Elasto-plastic time history analysis of a 117-story high structure

  • Wu, Xiaohan;Li, Yimiao;Zhang, Yunlei
    • Computers and Concrete
    • /
    • v.19 no.1
    • /
    • pp.7-17
    • /
    • 2017
  • In Chinese Design Codes, for super high-rise buildings with complex structural distribution, which are regarded as code-exceeding buildings, elasto-plastic time history analysis is needed to validate the requirement of "no collapse under rare earthquake". In this paper, a 117-story super high-rise building is discussed. It has a height of 597 m and a height-width ratio of 9.5, which have both exceeded the limitations stipulated by the Chinese Design Codes. Mega columns adopted in this structure have cross section area of about $45m^2$ at the bottom, which is infrequent in practical projects. NosaCAD and Perform-3D, both widely used in nonlinear analyses, were chosen in this study, with which two model were established and analyzed, respectively. Elasto-plastic time history analysis was conducted to look into its seismic behavior, emphasizing on the stress state and deformation abilities under intensive seismic excitation.From the comparisons on the results under rare earthquake obtained from NosaCAD and Perform-3D, the overall responses such as roof displacement, inter story drift, base shear and damage pattern of the whole structure from each software show agreement to an extent. Besides, the deformation of the structure is below the limitation of the Chinese Codes, the time sequence and distribution of damages on core tubes are reasonable, and can dissipate certain inputted energy, which indicates that the structure can meet the requirement of "no collapse under rare earthquake".

Earthquake Damage Assessment of Buildings in Urban Area using Disaster Management Platform (재난관리플랫폼을 이용한 도심지 건물군의 지진피해평가)

  • Jang, Sung-Hyun;Kwon, Dong-Hee;Hwang, Chan-Gyu;Choi, Soo-Young;Chey, Min-Ho
    • Journal of the Korea Convergence Society
    • /
    • v.10 no.6
    • /
    • pp.25-31
    • /
    • 2019
  • Because of its physical characteristics, earthquake has a great impact on a wide area in a short time, so it needs a resilience based seismic countermeasures to restore the community function. For this reason, in this study, the seismic damages of urban buildings were assessed stochastically by virtual earthquakes using public data information and disaster management program(Ergo-EQ). A geographical map reflecting geological characteristics of the target area was created with the buildings and topographic data in Dalseo-gu, Daegu City. In addition, an integrated database including building characteristics was modified to be linked with the Ergo-EQ program. The seismic damages for the buildings were evaluated through the exceedance probability of four different damage levels. From the damage results, it can be identified not only the seismic damage of each building, but also the major factors affecting earthquake damage.

Evaluation of Ductility and Damage Ratio for Reinforced Concrete Bridge Piers (철근콘크리트 교각의 연성과 손상도 평가)

  • Park, Chang-Gyu;Lee, Dae-Hyoung;Lee, Eun-Hee;Kim, Hoon;Chung, Young-Soo
    • Proceedings of the Earthquake Engineering Society of Korea Conference
    • /
    • 2002.09a
    • /
    • pp.197-204
    • /
    • 2002
  • The resent earthquakes in worldwide have caused extensive damage to highway reinforced concrete bridge piers. It has been observed in the Korean Peninsula that the number of minor or low earthquake motions have increased year by year. Since the concern about the earthquake hazards is increased, the objective of this research is to evaluate the damage of reinforced concrete bridge piers subjected to probable earthquake motions. Experimental investigation was conducted to study the seismic performance of the full-scale specimens in size D=1.2m H=4.8m, which were constructed with different longitudinal lap splice and loading pattern, through the quasi-static test and the pseudo-dynamic test. It is thought that this result could contribute to establish the retrofit decision-making and disaster planning of reinforced concrete bridge piers in earthquake regions. And it could be also possible to quantify the damage of reinforced concrete bridge piers under cyclic loading

  • PDF

Fragility Curve of PSC Box Girder Bridge using Isolator (면진 받침을 사용한 PSC Box Girder 교량의 손상도 곡선)

  • Lee, Jongheon;Kim, Woonhak;Seo, Sangmok
    • Journal of the Society of Disaster Information
    • /
    • v.8 no.1
    • /
    • pp.36-46
    • /
    • 2012
  • After the east Japan earthquake last March 2011, social interests are intensified in the area of increasing the earthquake resistant ability and the necessity of design method that can minimize the damage from earthquake. If bridges are damaged or collapsed, the social and economic effects are so severe that the evaluation of earthquake resistant ability becomes very important. The reviewing methods for earthquake resistant ability are many, but majority of these methods are deterministic. Thus, for the safety assessment of structures for earthquake, the method for evaluating fragility according to the stage of damage is necessary. In this paper, the fragility curves for PSC Box Girder bridge using LRB and RFPB are constructed for PGA, PGV, SA, SV, SI and the two isolators are compared.

Fragility Curve of Steel Box Bridge Using RFPB Bearing (RFPB 받침을 사용한 Steel Box 교량의 손상도 곡선)

  • Lee, Jongheon;Seo, Sangmok;Kim, Woonhak
    • Journal of the Society of Disaster Information
    • /
    • v.7 no.3
    • /
    • pp.171-180
    • /
    • 2011
  • As a great earthquake hit east Japan recently, the interests for the necessity of earthquake resistant design and earthquake resistance ability of existent structures are much increased. The damage or collapse of a bridge, as a social overhead capital structure affects socially and economically. Thus the evaluation of earthquake resistance ability of these structures is very important. The reviewing methods for earthquake resistance ability are mostly deterministic. Although the deterministic methods are fit for the evaluation of safety of each member, they are not practical for the whole structure. For the evaluation of structural safety for earthquake, the method for the evaluation of fragility or damage is needed for some stages of damage. In this paper, fragility curves of steel box bridge using RFPB bearing for PGA, PGV, SA, SV, SI are constructed, and these are compared with the cases of FPB.

Earthquake hazard and risk assessment of a typical Natural Gas Combined Cycle Power Plant (NGCCPP) control building

  • A. Can Zulfikar;Seyhan Okuyan Akcan;Ali Yesilyurt;Murat Eroz;Tolga Cimili
    • Geomechanics and Engineering
    • /
    • v.35 no.6
    • /
    • pp.581-591
    • /
    • 2023
  • North Anatolian Fault Zone is tectonically active with recent earthquakes (Mw7.6 1999-Kocaeli and Mw7.2 1999-Düzce earthquakes) and it passes through Marmara region, which is highly industrialized, densely populated and economically important part of Turkey. Many power plants, located in Marmara region, are exposed to high seismic hazard. In this study, open source OpenQuake software has been used for the probabilistic earthquake hazard analysis of Marmara region and risk assessment for the specified energy facility. The SHARE project seismic zonation model has been used in the analysis with the regional sources, NGA GMPEs and site model logic trees. The earthquake hazard results have been compared with the former and existing earthquake resistant design regulations in Turkey, TSC 2007 and TBSCD 2018. In the scope of the study, the seismic hazard assessment for a typical natural gas combined cycle power plant located in Marmara region has been achieved. The seismic risk assessment has been accomplished for a typical control building located in the power plant using obtained seismic hazard results. The structural and non-structural fragility functions and a consequence model have been used in the seismic risk assessment. Based on the seismic hazard level with a 2% probability of exceedance in 50 years, considered for especially these type of critical structures, the ratios of structural and non-structural loss to the total building cost were obtained as 8.8% and 45.7%, respectively. The results of the study enable the practical seismic risk assessment of the critical facility located on different regions.