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我國住宅地震保險法制重要問題研究 / Studies on the Legislations Regarding Residential Earthquake Insurance in Taiwan葉伊馨 Unknown Date (has links)
因台灣全島具有許多地震斷層,各處均有可能發生地震,又大型地震易伴隨之地震變動,常有斷層、山崩、地裂、地盤隆起、陷沒、崩崖、噴沙、噴泥、土壤液化、井水變化之情形發生。地震所造成之損失相當嚴重,若僅賴政府之事後救濟,將造成納稅人及國家沉重之財政負荷,相形之下,使人民事前投保地震保險,共同分散損失,乃較佳選擇。有鑑於位於高地震風險地區之國家,例如,位於「環太平洋地震帶」之日本、紐西蘭、美國加州,及位於「歐亞地震帶」之土耳其等,均陸續發展地震保險制度,故本論文欲藉各國地震保險制度,探討我國目前住宅地震保險制度之完善性。
本論文以此為主題,探討之內容包含地震風險是否具可保性、政府是否應介入地震保險市場、綜合天災保險之可行性、地震保險保費釐定之考量因素、是否應強制投保地震保險、強制承保之必要性、目前之投保方式是否構成違法之搭售行為、及理賠標準之爭議等問題,於論文最後並提出相關條文之修正建議。 / Earthquakes occur frequently in Taiwan, and they always lead to catastrophic losses. If the government invests more taxpayer dollars into ex post compensation, it will be unfair to other taxpayers. For insurance plays an important role in the modern societies. It can successfully distribute the risks ex ante and contribute to make societies more stable. So this paper introduces Earthquake Insurance to solve the problem, discusses the topic from different aspects, and does a comparative research on legislation between America, Japan, New Zealand, Turkey and Taiwan.
The outline of this paper discusses the insurability, the ways of risk management, the need of government intervention, whether to introduce mandatory insurance, the coverage extent the insurer can provide, and how to determine the premium. At the last of this paper, the author also raises some suggestions of Insurance Law.
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救災聯合體:中國大陸社會組織於汶川及雅安地震災難救援之轉變 / The Union of Disaster Rescue: The Transition of Social Organizations Rescue from Wenchuan to Yaan Earthquake in China潘彥璋, Pan, Yen Chang Unknown Date (has links)
本文以2008年汶川地震與2013年雅安地震為例,探究中國大陸國家與社會關係的變遷,一方面,剖析政府如何建立救災體系及管理社會組織,另一方面,剖析社會組織如何以聯合行動投入災難救援。學理層面,以「統合主義」與「資源動員理論」為基礎;實務層面,汶川地震救災時期選取「NGO四川救災聯合辦公室」、「四川512民間救助服務中心」為研究案例,雅安地震救災時期選取「深圳壹基金公益基金會」、「四川尚明公益發展研究中心」與「NGO備災中心」為研究案例,透過比較研究方式,探討國家結構與社會行動間的轉變。本文認為中國大陸社會組織類型除「官辦組織」(Government Organized Non-Governmental Organization,簡稱GONGO)與「非政府組織」(Non-Governmental Organization,簡稱NGO)外,存在另一社會組織類型領導及處理合法性與聯合性問題,即本文自行界定的「社會聚合型組織」(Society Congregated Non-Governmental Organization,簡稱SCNGO),期以提供新的研究角度。 / This article focuses on the transition of relationship between state and society from Wenchuan earthquake to Yaan earthquake in China. On the one hand, it analyses the government how to build disaster rescue system and manage social organization. On the other hand, it analyses social organization s how to rescue by collective action. The basis of theory is Corporatism and Resource Mobilization Theory. The case study of Wenchuan earthquake is NGO Sichuan Relief Joint Office and Sichuan 512 NGO Services Center. The case study of Yaan earthquake is One Foundation, Sichuan Shang Ming Social Development Research Center and NGO Disaster Preparedness Center. Through comparative study, it explores the transformation of state structures and social action. The type of social organization in China is Government Organized Non-Governmental Organization(GONGO) and Non-Governmental Organization (NGO). The author argues that there is another type of NGO that deal with organizational legality and collective action, and it names “Society Congregated Non-Governmental Organization(SCNGO). ” It wants to provide a new perspective.
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震災直後の被災者の受療行動からみた震災時医療圏域の設定に関する研究山下, 哲郎, 中山, 茂樹, 筧, 淳夫, 竹宮, 健司, 小林, 健一 03 1900 (has links)
科学研究費補助金 研究種目:基盤研究(B)(1) 課題番号:09555183 研究代表者:山下 哲郎 研究期間:1997-1998年度
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Comparative performance of ductile and damage protected bridge piers subjected to bi-directional earthquake attackMashiko, Naoto January 2006 (has links)
Incremental Dynamic Analysis (IDA) procedures are advanced and then applied to a quantitative risk assessment for bridge structures. This is achieved by combining IDA with site-dependent hazard-recurrence relations and damage outcomes. The IDA procedure is also developed as a way to select a critical earthquake motion record for a one-off destructive experiment. Three prototype bridge substructures are designed according to the loading and detailing requirements of New Zealand, Japan and Caltrans codes. From these designs 30 percent reduced scale specimens are constructed as part of an experimental investigation. The Pseudodynamic test is then to control on three specimens using the identified critical earthquake records. The results are presented in a probabilistic riskbased format. The differences in the seismic performance of the three different countries' design codes are examined. Each of these current seismic design codes strive for ductile behaviour of bridge substructures. Seismic response is expected to be resulting damage on structures, which may threaten post-earthquake serviceability. To overcome this major performance shortcoming, the seismic behaviour under bi-directional lateral loading is investigated for a bridge pier designed and constructed in accordance with Damage Avoidance principles. Due to the presence of steel armoured rocking interface at the base, it is demonstrated that damage can be avoided, but due to the lack of hysteresis it is necessary to add some supplemental damping. Experimental results of the armoured rocking pier under bi-directional loading are compared with a companion ductile design specimen.
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P-wave velocity model for the southwest of the Yilgarn Craton, Western Australia and its relation to the local geology and seismicityGalybin, Konstantin A January 2007 (has links)
[Truncated abstract] A number of controlled and natural seismic sources are utilised to model the Pwave velocity structure of the southwest of the Yilgarn Craton, Western Australia. The Yilgarn Craton is one of the largest pieces of Archaean crust in the world and is known for its gold and nickel deposits in the east and intraplate seismicity in the west. The aim of the project is to link 2D and 3D models of variations in seismic velocity with the local seismicity and geology. A new set of seismic refraction data, acquired in 25 overlapping deployments between 2002 and 2005, has been processed, picked and analysed using forward modelling. The data comprise two perpendicular traverses of three-component recordings of various delay-fired blasts from local commercial quarries. The data were processed using a variety of techniques. Tests were carried out on a number of data enhancement and picking procedures in order to determine the best method for enhancement of delay-fired data. A new method for automatic phase recognition is presented, where the maximum of the derivative of the rectilinearity of a trace is taken as the first break. Complete shot gathers with first break picks for each seismic source are compiled from the overlapping deployments. ... The starting 3D model was based on the models produced by 2D forward modelling. 14 iterations were carried out and the best-fit 3D model was achieved at the 10th iteration. It is 35% better then the current model used to locate earthquakes in this region. The resultant velocity block model was used to iii construct a density block model. A relative gravity map of the southwest of Yilgarn Craton was made. The results of 2D forward modelling, 3D tomography and forward gravity modelling have been compared and it was found that the HVZ is present in all models. Such a zone has been previously seen on a single seismic refraction profile, but it is the first time, this zone has been mapped in 3D. The gravity high produced by the zone coincides with the gravity high observed in reality. There is strong evidence that suggests that the HVZ forms part of the Archaean terrane boundary within the Yilgarn Craton. The distribution of the local seismicity was then discussed in the framework of the new 3D velocity model. A hypothesis, that the primary control on the seismicity in the study area is rotation of the major horizontal stress orientation, is presented. It is also argued that the secondary control on seismicity in the SWSZ is accommodation of movements along major faults.
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Comprehensive Seismic Hazard Analysis of IndiaKolathayar, Sreevalsa January 2012 (has links) (PDF)
Planet earth is restless and one cannot control its inside activities and vibrations those leading to natural hazards. Earthquake is one of such natural hazards that have affected the mankind most. Most of the causalities due to earthquakes happened not because of earthquakes as such, but because of poorly designed structures which could not withstand the earthquake forces. The improper building construction techniques adopted and the high population density are the major causes of the heavy damage due to earthquakes. The damage due to earthquakes can be reduced by following proper construction techniques, taking into consideration of appropriate forces on the structure that can be caused due to future earthquakes. The steps towards seismic hazard evaluation are very essential to estimate an optimal and reliable value of possible earthquake ground motion during a specific time period. These predicted values can be an input to assess the seismic vulnerability of an area based on which new construction and the restoration works of existing structures can be carried out.
A large number of devastating earthquakes have occurred in India in the past. The northern region of India, which is along the plate boundary of the Indian plate with the Eurasian plate, is seismically very active. The north eastern movement of Indian plate has caused deformation in the Himalayan region, Tibet and the North Eastern India. Along the Himalayan belt, the Indian and Eurasian plates converge at the rate of about 50 mm/year (Bilham 2004; Jade 2004). The North East Indian (NEI) region is known as one of the most seismically active regions in the world. However the peninsular India, which is far away from the plate boundary, is a stable continental region, which is considered to be of moderate seismic activity. Even though, the activity is considered to be moderate in the Peninsular India, world’s deadliest earthquake occurred in this region (Bhuj earthquake 2001). The rapid drifting of Indian plate towards Himalayas in the north east direction with a high velocity along with its low plate thickness might be the cause of high seismicity of the Indian region. Bureau of Indian Standard has published a seismic zonation map in 1962 and revised it in 1966, 1970, 1984 and 2002. The latest version of the seismic zoning map of India assigns four levels of seismicity for the entire Country in terms of different zone factors. The main drawback of the seismic zonation code of India (BIS-1893, 2002) is that, it is based on the past seismic activity and not based on a scientific seismic hazard analysis. Several seismic hazard studies, which were taken up in the recent years, have shown that the hazard values given by BIS-1893 (2002) need to be revised (Raghu Kanth and Iyengar 2006; Vipin et al. 2009; Mahajan et al. 2009 etc.). These facts necessitate a comprehensive study for evaluating the seismic hazard of India and development of a seismic zonation map of India based on the Peak Ground Acceleration (PGA) values. The objective of this thesis is to estimate the seismic hazard of entire India using updated seismicity data based on the latest and different methodologies.
The major outcomes of the thesis can be summarized as follows. An updated earthquake catalog that is uniform in moment magnitude, has been prepared for India and adjoining areas for the period till 2010. Region specific magnitude scaling relations have been established for the study region, which facilitated the generation of a homogenous earthquake catalog. By carefully converting the original magnitudes to unified MW magnitudes, we have removed a major obstacle for consistent assessment of seismic hazards in India. The earthquake catalog was declustered to remove the aftershocks and foreshocks. Out of 203448 events in the raw catalog, 75.3% were found to be dependent events and remaining 50317 events were identified as main shocks of which 27146 events were of MW ≥ 4. The completeness analysis of the catalog was carried out to estimate completeness periods of different magnitude ranges. The earthquake catalog containing the details of the earthquake events until 2010 is uploaded in the website the catalog was carried out to estimate completeness periods of different magnitude ranges. The earthquake catalog containing the details of the earthquake events until 2010 is uploaded in the website the catalog was carried out to estimate completeness periods of different magnitude ranges. The earthquake catalog containing the details of the earthquake events until 2010 is uploaded in the website
A quantitative study of the spatial distribution of the seismicity rate across India and its vicinity has been performed. The lower b values obtained in shield regions imply that the energy released in these regions is mostly from large magnitude events. The b
value of northeast India and Andaman Nicobar region is around unity which implies that the energy released is compatible for both smaller and larger events. The effect of aftershocks in the seismicity parameters was also studied. Maximum likelihood estimations of the b value from the raw and declustered earthquake catalogs show significant changes leading to a larger proportion of low magnitude events as foreshocks and aftershocks. The inclusions of dependent events in the catalog affect the relative abundance of low and high magnitude earthquakes. Thus, greater inclusion of dependent events leads to higher b values and higher activity rate. Hence, the seismicity parameters obtained from the declustered catalog is valid as they tend to follow a Poisson distribution. Mmax does not significantly change, since it depends on the largest observed magnitude rather than the inclusion of dependent events (foreshocks and aftershocks). The spatial variation of the seismicity parameters can be used as a base to identify regions of similar characteristics and to delineate regional seismic source zones.
Further, Regions of similar seismicity characteristics were identified based on fault alignment, earthquake event distribution and spatial variation of seismicity parameters. 104 regional seismic source zones were delineated which are inevitable input to seismic hazard analysis. Separate subsets of the catalog were created for each of these zones and seismicity analysis was done for each zone after estimating the cutoff magnitude. The frequency magnitude distribution plots of all the source zones can be found at http://civil.iisc.ernet.in/~sitharam . There is considerable variation in seismicity parameters and magnitude of completeness across the study area. The b values for various regions vary from a lower value of 0.5 to a higher value of 1.5. The a value for different zones vary from a lower value of 2 to a higher value of 10. The analysis of seismicity parameters shows that there is considerable difference in the earthquake recurrence rate and Mmax in India. The coordinates of these source zones and the seismicity parameters a, b & Mmax estimated can be directly input into the Probabilistic seismic hazard analysis. The seismic hazard evaluation of the Indian landmass based on a state-of-the art Probabilistic Seismic Hazard Analysis (PSHA) study has been performed using the classical Cornell–McGuire approach with different source models and attenuation relations. The most recent knowledge of seismic activity in the region has been used to evaluate the hazard incorporating uncertainty associated with different modeling parameters as well as spatial and temporal uncertainties. The PSHA has been performed with currently available data and their best possible scientific interpretation using an appropriate instrument such as the logic tree to explicitly account for epistemic uncertainty by considering alternative models (source models, maximum magnitude in hazard computations, and ground-motion attenuation relationships). The hazard maps have been produced for horizontal ground motion at bedrock level (Shear wave velocity ≥ 3.6 km/s) and compared with the earlier studies like Bhatia et al., 1999 (India and adjoining areas); Seeber et al, 1999 (Maharashtra state); Jaiswal and Sinha, 2007 (Peninsular India); Sitharam and Vipin, 2011 (South India); Menon et al., 2010 (Tamilnadu). It was observed that the seismic hazard is moderate in Peninsular shield (except the Kutch region of Gujarat), but the hazard in the North and Northeast India and Andaman-Nicobar region is very high. The ground motion predicted from the present study will not only give hazard values for design of structures, but also will help in deciding the locations of important structures such as nuclear power plants.
The evaluation of surface level PGA values is of very high importance in the engineering design. The surface level PGA values were evaluated for the entire study area for four NEHRP site classes using appropriate amplification factors. If the site class at any location in the study area is known, then the ground level PGA values can be obtained from the respective map. In the absence of VS30 values, the site classes can be identified based on local geological conditions. Thus this method provides a simplified methodology for evaluating the surface level PGA values. The evaluation of PGA values for different site classes were evaluated based on the PGA values obtained from the DSHA and PSHA. This thesis also presents VS30 characterization of entire country based on the topographic gradient using existing correlations. Further, surface level PGA contour map was developed based on the same. Liquefaction is the conversion of formally stable cohesionless soils to a fluid mass, due to increase in pore pressure and is prominent in areas that have groundwater near the surface and sandy soil. Soil liquefaction has been observed during the earthquakes because of the sudden dynamic earthquake load, which in turn increases the pore pressure. The evaluation of liquefaction potential involves evaluation of earthquake loading and evaluation of soil resistance to liquefaction. In the present work, the spatial variation of the SPT value required to prevent liquefaction has been estimated using a probabilistic methodology, for entire India.
To summarize, the major contribution of this thesis are the development of region specific magnitude correlations suitable for Indian subcontinent and an updated homogeneous earthquake catalog for India that is uniform in moment magnitude scale. The delineation and characterization of regional seismic source zones for a vast country like India is a unique contribution, which requires reasonable observation and engineering judgement. Considering complex seismotectonic set up of the country, the present work employed numerous methodologies (DSHA and PSHA) in analyzing the seismic hazard using appropriate instrument such as the logic tree to explicitly account for epistemic uncertainties considering alternative models (For Source model, Mmax estimation and Ground motion prediction equations) to estimate the PGA value at bedrock level. Further, VS30 characterization of India was done based on the topographic gradient, as a first level approach, which facilitated the development of surface level PGA map for entire country using appropriate amplification factors. Above factors make the present work very unique and comprehensive touching various aspects of seismic hazard. It is hoped that the methodology and outcomes presented in this thesis will be beneficial to practicing engineers and researchers working in the area of seismology and geotechnical engineering in particular and to the society as a whole.
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Seismic Site Response Evaluation Using Ambient Vibrations And Earthquakes : Applications in Active And Vulnerable Regions with Emphasis on the 2001 Bhuj (India) EarthquakeNatarajan, Thulasiraman January 2016 (has links) (PDF)
Local site conditions are known to influence ground motion during earthquake events and increase the severity of damage. Data from earthquakes are useful to study the response but they are available only from active regions. Ubiquitous ambient vibrations on the other hand offer a more practical approach to quantify site responses. This thesis explores the use of various methods for obtaining site responses. The primary area of study is the Kachchh rift basin, NW India, a Mesozoic rift that features significant lateral variations in surface geology and has experienced ground responses during 1819 and 2001 earthquakes. The Mw 7.6, 2001 event was followed by hundreds of aftershocks, which were recorded by temporary networks. In this study we have used earthquake signals as well as ambient vibrations to understand site response in various parts of the basin. In addition we have collected data from a few sites from the Indo-Gangetic plains and Kathmandu valley, both affected by large earthquakes, 1934 the M ~ 8 (Bihar) and 2015, Mw 7.8 (Nepal). Velocity and acceleration records from a network of eight stations in the Kachchh Rift were used to evaluate site responses using Standard Spectral Ratio (SSR) and Horizontal to Vertical spectral ratio (HVSR-E) methods. Ambient vibrations were analyzed following Nakamura’s H/V method (HVSR-AV), for data collected from 110 sites that represent different field conditions within the Kachchh Rift. Fundamental resonance frequency (f0) varied between 0.12 – 2.30 Hz, while the amplification factor (A0) was in the range of 2.0 – 9.1. We found that higher A0 and liquefaction index (Kg) values were mostly associated with higher liquefaction potential. Using a close network of stations, we studied the role of site response in damage to the Bhuj city that suffered maximum damage in 2001; our results suggest that site response was not a significant factor.
Studies based on passive data were complemented by Multi-channel Analysis of Surface Waves (MASW) to map shear wave velocities of the various subsurface units up to depths of 10m (Vs10) and 30m (Vs30). Our results imply average Vs could be a good proxy to characterize site amplifications where sediment thicknesses are shallow. Power law relationship between f0 and thickness (h) suggest a strong positive correlation (r = 0.89) adding credence to HVSR-AV method, making it a cost-effective alternative to MASW to infer site conditions. Further, to understand the influence of topography on site effects, we analyzed data from hills, valleys and their edges, both from the Kachchh rift and Kathmandu valley. Sites on the edges of valleys showed multiple, fuzzy peaks in the low frequency range (< 1 Hz) and broad peaks attributable to sites prone to higher damage. Spectrograms generated through Huang-Hilbert Transforms (HHT) suggested focusing of energy in narrow frequency bands on the edges, while valleys tend to scatter energy over wide frequencies.
Although our current results are based on limited observations, we recognize spectral analysis as a powerful tool to quantify site effects in regions with significant topography.
It is known that coseismic liquefaction could lead to nonlinear behavior wherein the near-surface soil layer loses its shear strength, causing a reduction of its fundamental resonance frequency. We used data from selected sites of coseismic liquefaction to highlight the significance of nonlinear effects in site response. Earthquake signals and ambient vibrations from Umedpur, a region that experienced intense liquefaction during 2001 were used in this analysis. Here we followed an empirical decomposition method based on HHT and signals were decomposed as many intrinsic mode functions (IMFs) that showed characteristic peaks for events of various values of PGAs. Thus, the first IMF for events with relatively higher PGAs (0.03g) showed distinct peaks for the S wave coda part, which were not noted for those with lower PGA (0.01g). These observations in a region of coseismic liquefaction are useful in developing models for quantifying nonlinear behavior.
In conclusion, site response studies using different types of data and processing techniques in regions affected by recent earthquakes brings out the scope and limitations of each of these sets of data and techniques. This study suggests that ambient vibrations provide reasonable estimates of site response and can be reliably used in regions where earthquake data are not available.
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Study of Fragility Functions for Assessing Damage to Water Pipe Networks Caused by Earthquake LoadingMerlo, Dylan Joseph 01 April 2021 (has links) (PDF)
The performance of water lifelines during seismic events is an area of ongoing research. In this study we evaluate eight (8) different seismic events and the impact that ground shaking and ground deformations had on water pipeline systems. The overall goal of this work is to provide municipalities and utility providers with tools for mitigating the consequences of seismic hazards on water lifeline systems by analyzing the accuracy of damage estimation models. Three (3) different repair rate models are evaluated using data collected from the seismic events and compared to observed repair rate data. Results are analyzed to examine the utility of the models for forecasting damage. Results are shown. The overall goal of this work is to provide municipalities and utility providers with tools for mitigating the consequences of seismic hazards on water lifeline systems by analyzing the accuracy of damage estimation models.
Results indicate that fragility functions that utilize a linear PGV-based function are the most accurate in predicting repair rates to a system based on residual plots developed for different models. Differentiating between continuous and segmented water lifeline systems is best done by using coefficients to modify the backbone PGV-based equation. Results also indicate that utilizing an additional PGD-based function could increase the predictive capabilities of water lifeline system fragility functions.
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An explicit finite difference method for analyzing hazardous rock massBasson, Gysbert 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2011. / ENGLISH ABSTRACT: FLAC3D is a three-dimensional explicit nite difference program for solving a variety of
solid mechanics problems, both linear and non-linear. The development of the algorithm
and its initial implementation were performed by Itasca Consulting Group Inc. The main
idea of the algorithm is to discritise the domain of interest into a Lagrangian grid where
each cell represents an element of the material. Each cell can then deform according to a
prescribed stress/strain law together with the equations of motion. An in-depth study of
the algorithm was performed and implemented in Java. During the implementation, it was
observed that the type of boundary conditions typically used has a major in uence on the
accuracy of the results, especially when boundaries are close to regions with large stress
variations, such as in mining excavations. To improve the accuracy of the algorithm, a
new type of boundary condition was developed where the FLAC3D domain is embedded
in a linear elastic material, named the Boundary Node Shell (BNS). Using the BNS
shows a signi cant improvement in results close to excavations. The FLAC algorithm is
also quite amendable to paralellization and a multi-threaded version that makes use of multiple Central Processing Unit (CPU) cores was developed to optimize the speed of the
algorithm. The nal outcome is new non-commercial Java source code (JFLAC) which
includes the Boundary Node Shell (BNS) and shared memory parallelism over and above
the basic FLAC3D algorithm. / AFRIKAANSE OPSOMMING: FLAC3D is 'n eksplisiete eindige verskil program wat 'n verskeidenheid liniêre en nieliniêre soliede meganika probleme kan oplos. Die oorspronklike algoritme en die implimentasies
daarvan was deur Itasca Consulting Group Inc. toegepas. Die hoo dee van die
algoritme is om 'n gebied te diskritiseer deur gebruik te maak van 'n Lagrangese rooster,
waar elke sel van die rooster 'n element van die rooster materiaal beskryf. Elke sel kan
dan vervorm volgens 'n sekere spannings/vervormings wet. 'n Indiepte ondersoek van
die algoritme was uitgevoer en in Java geïmplimenteer. Tydens die implementering was
dit waargeneem dat die grense van die rooster 'n groot invloed het op die akkuraatheid
van die resultate. Dit het veral voorgekom in areas waar stress konsentrasies hoog is,
gewoonlik naby areas waar myn uitgrawings gemaak is. Dit het die ontwikkelling van 'n
nuwe tipe rand kondisie tot gevolg gehad, sodat die akkuraatheid van die resultate kon
verbeter. Die nuwe rand kondisie, genaamd die Grens Node Omhulsel (GNO), aanvaar
dat die gebied omring is deur 'n elastiese materiaal, wat veroorsaak dat die grense van die
gebied 'n elastiese reaksie het op die stress binne die gebied. Die GNO het 'n aansienlike verbetering in die resultate getoon, veral in areas naby myn uitgrawings. Daar was ook
waargeneem dat die FLAC algoritme parralleliseerbaar is en het gelei tot die implentering
van 'n multi-SVE weergawe van die sagteware om die spoed van die algoritme te optimeer.
Die nale uitkomste is 'n nuwe nie-kommersiële Java weergawe van die algoritme
(JFLAC), wat die implimentering van die nuwe GNO randwaardekondisie insluit, asook
toelaat vir die gebruik van multi- Sentrale Verwerkings Eenheid (SVE) as 'n verbetering
op die basiese FLAC3D algoritme.
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Earthquake Sources and Hazard in northern Central America / Zonas y Amenaza Sísmica en el norte de America CentralCáceres Calix, Diego José January 2003 (has links)
Northern Central America is a tectonically complex zone defined by its borders with Cocos and North America plates. The Middle America subduction zone and the strike-slip motion along the North America-Caribbean plate boundary, in that order, control most of its deformation. The interaction between the different elements of the studied area is evident from the high seismicity in the region, especially along plate boundaries. Also in the interior of the region, seismicity shows that deformation takes place, though in lesser degree. In a time window of 30 years, three earthquakes with moment magnitude larger than 7 struck northern Central America evincing the need to estimate the seismic hazard for the zone. To tackle the problem, we compiled a catalogue of hypocenters commencing in 1964, defined seismogenic sources and described the evolution of earthquake activity through a Poisson model. Probabilistic seismic hazard (PSH) calculations for the next 50 years were performed. The highest estimate of seismic hazard was obtained for the zone adjacent to the subduction zone. Because of the fundamental importance of demarcating seismogenic sources in the PSH analysis, i.e. defining the seismotectonic model, we extended the catalogue to cover 102 years for the whole northern Central America. We have studied the North America-Caribbean plate boundary in order to refine the fault representation. Different techniques were used, like that of body-waveform modeling, allowing us to limit the extent of depth of faulting to 20 km. The seismic moment tensor was used to estimate the deformation velocities on known tectonic structures, including those of the Honduras depression and borderland faults. Finally, we made use of the Coulomb stress criterion to determine the relation between earthquake occurrence and static stress changes following major earthquakes.
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