Journal articles on the topic 'Earthquake engineering – Mathematics'
To see the other types of publications on this topic, follow the link: Earthquake engineering – Mathematics.
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Earthquake engineering – Mathematics.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
English, Lyn D., and Donna T. King. "Designing an Earthquake-Resistant Building." Teaching Children Mathematics 23, no. 1 (August 2016): 47–50. http://dx.doi.org/10.5951/teacchilmath.23.1.0047.
Full textAbstract:
Contributors to the iSTEM (Integrating Science, Technology, Engineering, and Mathematics) department share ideas and activities that stimulate student interest in the integrated fields of science, technology, engineering, and mathematics (STEM) in K–grade 6 classrooms. This article is a comprehensive Earthquake Engineering activity that includes the Designing an earthquake-resistant building problem. The task was implemented in sixth-grade classes (10–11-year-olds). Students applied engineering design processes and their understanding of cross-bracing, tapered geometry, and base isolation to create numerous structures, which they tested on a “shaker table.”
2
Kanamori, Hiroo. "Lessons from the 2004 Sumatra–Andaman earthquake." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 364, no. 1845 (June 27, 2006): 1927–45. http://dx.doi.org/10.1098/rsta.2006.1806.
Full textAbstract:
The 2004 Sumatra–Andaman earthquake ( M w =9.0–9.3) is one of the greatest earthquakes ever recorded. In terms of its physical size, it is comparable to the 1960 Chilean ( M w =9.5) and the 1965 Alaskan ( M w =9.2) earthquakes. However, the damage caused by this earthquake is far greater than that caused by other great earthquakes. The 2004 Sumatra–Andaman earthquake has been studied in great detail over broad time-scales, from a fraction of seconds to hours and months, using the modern seismic data available from global seismic networks and the Global Positioning System data. We summarize the findings obtained mainly from seismic data, and discuss the unique feature of this earthquake, and possible directions of research to minimize the impact of great earthquakes on our society.
3
Satake, Kenji. "Geological and historical evidence of irregular recurrent earthquakes in Japan." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 373, no. 2053 (October 28, 2015): 20140375. http://dx.doi.org/10.1098/rsta.2014.0375.
Full textAbstract:
Great ( M ∼8) earthquakes repeatedly occur along the subduction zones around Japan and cause fault slip of a few to several metres releasing strains accumulated from decades to centuries of plate motions. Assuming a simple ‘characteristic earthquake’ model that similar earthquakes repeat at regular intervals, probabilities of future earthquake occurrence have been calculated by a government committee. However, recent studies on past earthquakes including geological traces from giant ( M ∼9) earthquakes indicate a variety of size and recurrence interval of interplate earthquakes. Along the Kuril Trench off Hokkaido, limited historical records indicate that average recurrence interval of great earthquakes is approximately 100 years, but the tsunami deposits show that giant earthquakes occurred at a much longer interval of approximately 400 years. Along the Japan Trench off northern Honshu, recurrence of giant earthquakes similar to the 2011 Tohoku earthquake with an interval of approximately 600 years is inferred from historical records and tsunami deposits. Along the Sagami Trough near Tokyo, two types of Kanto earthquakes with recurrence interval of a few hundred years and a few thousand years had been recognized, but studies show that the recent three Kanto earthquakes had different source extents. Along the Nankai Trough off western Japan, recurrence of great earthquakes with an interval of approximately 100 years has been identified from historical literature, but tsunami deposits indicate that the sizes of the recurrent earthquakes are variable. Such variability makes it difficult to apply a simple ‘characteristic earthquake’ model for the long-term forecast, and several attempts such as use of geological data for the evaluation of future earthquake probabilities or the estimation of maximum earthquake size in each subduction zone are being conducted by government committees.
4
Vinod, J. S. "Dem Simulations in Geotechnical Earthquake Engineering Education." International Journal of Geotechnical Earthquake Engineering 1, no. 1 (January 2010): 61–69. http://dx.doi.org/10.4018/jgee.2010090804.
Full textAbstract:
Behaviour of geotechnical material is very complex. Most of the theoretical frame work to understand the behaviour of geotechnical materials under different loading conditions depends on the strong background of the basic civil engineering subjects and advanced mathematics. However, it is fact that the complete behaviour of geotechnical material cannot be traced within theoretical framework. Recently, computational models based on Finite Element Method (FEM) are used to understand the behaviour of geotechnical problems. FEM models are quite complex and is of little interest to undergraduate students. A simple computational tool developed using Discrete Element Method (DEM) to simulate the laboratory experiments will be cutting edge research for geotechnical earthquake engineering education. This article summarizes the potential of DEM to simulate the cyclic triaxial behaviour of granular materials under complex loading conditions. It is shown that DEM is capable of simulating the cyclic behavior of granular materials (e.g. undrained, liquefaction and post liquefaction) similar to the laboratory experiments.
5
FRAGIADAKIS, MICHALIS, and MANOLIS PAPADRAKAKIS. "MODELING, ANALYSIS AND RELIABILITY OF SEISMICALLY EXCITED STRUCTURES: COMPUTATIONAL ISSUES." International Journal of Computational Methods 05, no. 04 (December 2008): 483–511. http://dx.doi.org/10.1142/s0219876208001674.
Full textAbstract:
A critical review of the current state of the art of the computing practices adopted by the earthquake engineering community is presented. Advanced computational tools are necessary for estimating the demand on seismically excited structures. Such computational methodologies can provide valuable information on a number of engineering parameters which have been proven essential for earthquake the engineering practice. The discussion extends from the finite element modeling of earthquake-resistant structures and the analysis procedures currently used to future developments considering the calculation of uncertainty and methodologies which rely on sophisticated computational methods. The objective is to provide a common ground of collaboration between the earthquake engineering and computational mechanics communities in an effort to mitigate future earthquake losses.
6
Jackson, James. "Fatal attraction: living with earthquakes, the growth of villages into megacities, and earthquake vulnerability in the modern world." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 364, no. 1845 (June 27, 2006): 1911–25. http://dx.doi.org/10.1098/rsta.2006.1805.
Full textAbstract:
The great earthquake belt which stretches from the Mediterranean through the Middle East into Central Asia results from the ongoing collision between the Eurasian plate and the African, Arabian and Indian plates to the south. Through much of this belt, the topography is created and controlled by fault movement in earthquakes. Many habitations are located at the foot of the fault-controlled mountain range-fronts that bound inhospitable deserts or elevated plateaus, in positions that are favourable for trade-routes, strategic control of access or for water supply. As a result, they are vulnerable to earthquakes, which often seem to have targeted population centres precisely. For many centuries, an uneasy accommodation was reached between human needs and the earthquake-controlled landscape, sometimes brilliantly exploited by local hydrological engineering, as in Iran. Occasional earthquakes would occur, killing a shocking proportion of the population, but the populations of the settlements themselves would be relatively small. Many once-small rural communities have now grown into towns, cities or megacities, while retaining their vulnerability through poor building standards. Earthquakes that occur in these places today now kill many more than they did in the past, as we have witnessed in the last few years. Extreme catastrophes have been rare only because the exposure of modern megacities to earthquake hazards has been relatively short (approx. 50 years); an increase in the number of such catastrophes now seems to be inevitable.
7
Olsen-Kettle, Louise, Hans Mühlhaus, and Christian Baillard. "A study of localization limiters and mesh dependency in earthquake rupture." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 368, no. 1910 (January 13, 2010): 119–30. http://dx.doi.org/10.1098/rsta.2009.0190.
Full textAbstract:
No complete physically consistent model of earthquake rupture exists that can fully describe the rich hierarchy of scale dependencies and nonlinearities associated with earthquakes. We study mesh sensitivity in numerical models of earthquake rupture and demonstrate that this mesh sensitivity may provide hidden clues to the underlying physics generating the rich dynamics associated with earthquake rupture. We focus on unstable slip events that occur in earthquakes when rupture is associated with frictional weakening of the fault. Attempts to simulate these phenomena directly by introducing the relevant constitutive behaviour leads to mesh-dependent results, where the deformation localizes in one element, irrespective of size. Interestingly, earthquake models with oversized mesh elements that are ill-posed in the continuum limit display more complex and realistic physics. Until now, the mesh-dependency problem has been regarded as a red herring—but have we overlooked an important clue arising from the mesh sensitivity? We analyse spatial discretization errors introduced into models with oversized meshes to show how the governing equations may change because of these error terms and give rise to more interesting physics.
8
De La Flor, Grace, Mobin Ojaghi, Ignacio Lamata Martínez, Marina Jirotka, Martin S. Williams, and Anthony Blakeborough. "Reconfiguring practice: the interdependence of experimental procedure and computing infrastructure in distributed earthquake engineering." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 368, no. 1926 (September 13, 2010): 4073–88. http://dx.doi.org/10.1098/rsta.2010.0140.
Full textAbstract:
When transitioning local laboratory practices into distributed environments, the interdependent relationship between experimental procedure and the technologies used to execute experiments becomes highly visible and a focal point for system requirements. We present an analysis of ways in which this reciprocal relationship is reconfiguring laboratory practices in earthquake engineering as a new computing infrastructure is embedded within three laboratories in order to facilitate the execution of shared experiments across geographically distributed sites. The system has been developed as part of the UK Network for Earthquake Engineering Simulation e-Research project, which links together three earthquake engineering laboratories at the universities of Bristol, Cambridge and Oxford. We consider the ways in which researchers have successfully adapted their local laboratory practices through the modification of experimental procedure so that they may meet the challenges of coordinating distributed earthquake experiments.
9
Abercrombie, Rachel E. "Resolution and uncertainties in estimates of earthquake stress drop and energy release." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 379, no. 2196 (March 15, 2021): 20200131. http://dx.doi.org/10.1098/rsta.2020.0131.
Full textAbstract:
Our models and understanding of the dynamics of earthquake rupture are based largely on estimates of earthquake source parameters, such as stress drop and radiated seismic energy. Unfortunately, the measurements, especially those of small and moderate-sized earthquakes (magnitude less than about 5 or 6), are not well resolved, containing significant random and potentially systematic uncertainties. The aim of this review is to provide a context in which to understand the challenges involved in estimating these measurements, and to assess the quality and reliability of reported measurements of earthquake source parameters. I also discuss some of the ways progress is being made towards more reliable parameter measurements. At present, whether the earthquake source is entirely self-similar, or not, and which factors and processes control the physics of the rupture remains, at least in the author's opinion, largely unconstrained. Detailed analysis of the best recorded earthquakes, using the increasing quantity and quality of data available, and methods less dependent on simplistic source models is one approach that may help provide better constraints. This article is part of the theme issue ‘Fracture dynamics of solid materials: from particles to the globe’.
10
KR. AGRAWAL, SHAILESH. "GENERATION OF SYNTHETIC ACCELEROGRAMS USING ENGINEERING EARTHQUAKE SOURCE MODEL." International Journal of Structural Stability and Dynamics 04, no. 04 (December 2004): 497–514. http://dx.doi.org/10.1142/s0219455404001343.
Full textAbstract:
The strong motion records available during an earthquake can be treated as the response of the earth as a structural system to unknown forces acting at unknown locations. Thus, if the part of the earth participating in ground motion is modeled as a known finite elastic medium, one can model the source location and forces generated during the earthquake as an inverse problem. Based on this analogy, a simple model for the earthquake source is proposed, by assuming the source to be a sequence of impulses acting at locations yet to be found. These impulses and their locations are found using the normal mode expansion along with a minimization of mean squared error. The medium is assumed to be finite, elastic, homogeneous, layered and horizontal with specified boundary conditions. Detailed results are obtained for the Uttarkashi earthquake of 20th October 1991, in India. The impulse locations are shown to be closely associated with the underlying fault mechanism. The proposed model is then used to simulate the acceleration time histories at a few recording stations. The earthquake source expressed in terms of a sequence of impulses acting at different locations is applied to a 2D finite elastic medium. The acceleration time histories found from this model agree well with with the accelerations recorded for the earthquake.
11
Guo, Wei, Yao Hu, Hanyun Liu, and Dan Bu. "Seismic Performance Evaluation of Typical Piers of China’s High-Speed Railway Bridge Line Using Pushover Analysis." Mathematical Problems in Engineering 2019 (July 1, 2019): 1–17. http://dx.doi.org/10.1155/2019/9514769.
Full textAbstract:
Currently, it is a challenge to effectively assess the seismic performance of the high-speed railway bridge line. To figure it out, this paper discussed the applicability of the Pushover analysis in the seismic fragility of the high-speed railway bridge. As the piers are the core components to resist the earthquakes, a typical high-speed railway bridge line consisting of 22 piers was established by the finite element software OpenSees. The influences of the different pier height and sites on the fragility analysis of the pies were investigated. From the component level, the seismic performance of the high-speed railway bridge line was evaluated by the Pushover analysis. The results show that the seismic responses of the piers by the Pushover analysis are agreeable with those by the incremental dynamical analysis when the peak ground acceleration is less than 0.4g. The high piers have better seismic performance than the lower piers. The high-speed railway bridge line exhibits good seismic performance under the 7-degree design earthquake (0.15g) and the 8-degree low-level earthquake (0.10g) but may be severely damaged under the 9-degree low-level earthquake (0.40g).
12
Vallianatos, Filippos, Giorgos Papadakis, and Georgios Michas. "Generalized statistical mechanics approaches to earthquakes and tectonics." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 472, no. 2196 (December 2016): 20160497. http://dx.doi.org/10.1098/rspa.2016.0497.
Full textAbstract:
Despite the extreme complexity that characterizes the mechanism of the earthquake generation process, simple empirical scaling relations apply to the collective properties of earthquakes and faults in a variety of tectonic environments and scales. The physical characterization of those properties and the scaling relations that describe them attract a wide scientific interest and are incorporated in the probabilistic forecasting of seismicity in local, regional and planetary scales. Considerable progress has been made in the analysis of the statistical mechanics of earthquakes, which, based on the principle of entropy, can provide a physical rationale to the macroscopic properties frequently observed. The scale-invariant properties, the (multi) fractal structures and the long-range interactions that have been found to characterize fault and earthquake populations have recently led to the consideration of non-extensive statistical mechanics (NESM) as a consistent statistical mechanics framework for the description of seismicity. The consistency between NESM and observations has been demonstrated in a series of publications on seismicity, faulting, rock physics and other fields of geosciences. The aim of this review is to present in a concise manner the fundamental macroscopic properties of earthquakes and faulting and how these can be derived by using the notions of statistical mechanics and NESM, providing further insights into earthquake physics and fault growth processes.
13
Işık, Ercan, Ehsan Harirchian, Aydın Büyüksaraç, and Yunus Levent Ekinci. "Seismic and Structural Analyses of the Eastern Anatolian Region (Turkey) Using Different Probabilities of Exceedance." Applied System Innovation 4, no. 4 (November 11, 2021): 89. http://dx.doi.org/10.3390/asi4040089.
Full textAbstract:
Seismic hazard analysis of the earthquake-prone Eastern Anatolian Region (Turkey) has become more important due to its growing strategic importance as a global energy corridor. Most of the cities in that region have experienced the loss of life and property due to significant earthquakes. Thus, in this study, we attempted to estimate the seismic hazard in that region. Seismic moment variations were obtained using different types of earthquake magnitudes such as Mw, Ms, and Mb. The earthquake parameters were also determined for all provincial centers using the earthquake ground motion levels with some probabilities of exceedance. The spectral acceleration coefficients were compared based on the current and previous seismic design codes of the country. Additionally, structural analyses were performed using different earthquake ground motion levels for the Bingöl province, which has the highest peak ground acceleration values for a sample reinforced concrete building. The highest seismic moment variations were found between the Van and Hakkari provinces. The findings also showed that the peak ground acceleration values varied between 0.2–0.7 g for earthquakes, with a repetition period of 475 years. A comparison of the probabilistic seismic hazard curves of the Bingöl province with the well-known attenuation relationships showed that the current seismic design code indicates a higher earthquake risk than most of the others.
14
Pan, Shenrun, and Manzhi Li. "Construction of Earthquake Rescue Model Based on Hierarchical Voronoi Diagram." Mathematical Problems in Engineering 2020 (May 22, 2020): 1–13. http://dx.doi.org/10.1155/2020/4576093.
Full textAbstract:
Traditional earthquake rescue methods have many problems, such as the impact of road damage on earthquake rescue, the rational allocation of disaster relief materials, and the active division of rescue areas. According to the characteristics of earthquake relief, a new earthquake rescue model is designed from three aspects: high-altitude rescue, road transport relief supplies, and street human resources rescue. In this paper, the hierarchical Voronoi diagram is applied to the earthquake rescue problem, the earthquake rescue model is constructed, and the area affected by the earthquake is reasonably divided. We discussed the earthquake intensity and the proportion of the population in the disaster area and the number of disaster relief materials and other parameters and conducted an in-depth analysis of the model to form a useful earthquake rescue model. Visual simulation results have been obtained by computer simulation. Compared with the traditional earthquake rescue plan, the model proposed in this paper is more effective and scientific in improving the material distribution, personnel rescue, and postdisaster reconstruction after the earthquake, and it also provides a new idea for the rescue of other natural disasters. It has practical social value and broad application prospects. Besides, the models and conclusions given in this paper have been recognized by the Seismological Bureau of Hainan Province and the Mathematics Research Center of Hainan Province.
15
Guo, Jidong, Menghao Xi, Yong Cheng, and Heyan Jiao. "Postearthquake Casualty Prediction Based on Heatmaps and Wavelet Supporting Vector Machines." Mathematical Problems in Engineering 2022 (August 25, 2022): 1–12. http://dx.doi.org/10.1155/2022/3998655.
Full textAbstract:
The prediction of casualties in earthquakes is very important for improving the efficiency of emergency rescue measures and reducing the number of casualties. Given the time lag and poor accuracy of population density data published in statistical yearbooks, a Baidu heatmap is used in this study to accurately estimate the regional population density. Based on the standard support vector machine (SVM) prediction model, a piecewise loss function and a robust wavelet kernel function are proposed to effectively reduce the prediction error. Given a characteristic attribute set of factors related to earthquake casualties, the new prediction model is tested in 34 cases involving earthquake cases on the Chinese mainland since 2011. Compared with other prediction techniques, the proposed robust wavelet SVM can converge more quickly, and the prediction error is lower than that of the standard backpropagation neural network (BPNN) and standard SVM.
16
Sornette, Didier, Euan Mearns, and Spencer Wheatley. "Revisiting the Predictability of the Haicheng and Tangshan Earthquakes." Symmetry 13, no. 7 (July 5, 2021): 1206. http://dx.doi.org/10.3390/sym13071206.
Full textAbstract:
We analyze a set of precursory data measured before but compiled in retrospect of the MS7.5 Haicheng earthquake in February 1975 and the MS7.6–7.8 Tangshan earthquake in July 1976. We propose a robust and simple coarse-graining method that aggregates and counts how all the anomalies together (levelling, geomagnetism, soil resistivity, earth currents, gravity, earth stress, well water radon, well water level) develop as a function of time. We demonstrate strong evidence for the existence of an acceleration of the number of anomalies leading up to the major Haicheng and Tangshan earthquakes. In particular for the Tangshan earthquake, the frequency of occurrence of anomalies is found to be well described by the log-periodic power law singularity (LPPLS) model, previously proposed for the prediction of engineering failures and later adapted to the prediction of financial crashes. Using a mock real-time prediction experiment and simulation study, based on this methodology of monitoring accelerated rates of physical anomalies measured at the surface, we show the potential for an early warning system with a lead time of a few days.
17
Biswas, Soumyajyoti, and Lucas Goehring. "Mapping heterogeneities through avalanche statistics." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 377, no. 2136 (November 26, 2018): 20170388. http://dx.doi.org/10.1098/rsta.2017.0388.
Full textAbstract:
Avalanche statistics of various threshold-activated dynamical systems are known to depend on the magnitude of the drive, or stress, on the system. Such dependences exist for earthquake size distributions, in sheared granular avalanches, laboratory-scale fracture and also in the outage statistics of power grids. In this work, we model threshold-activated avalanche dynamics and investigate the time required to detect local variations in the ability of model elements to bear stress. We show that the detection time follows a scaling law where the scaling exponents depend on whether the feature that is sought is either weaker, or stronger, than its surroundings. We then look at earthquake data from Sumatra and California, demonstrate the trade-off between the spatial resolution of a map of earthquake exponents (i.e. the b -values of the Gutenberg–Richter Law) and the accuracy of those exponents, and suggest a means to maximize both. This article is part of the theme issue ‘Statistical physics of fracture and earthquakes’.
18
Li, Duo, and Yajing Liu. "Cascadia megathrust earthquake rupture model constrained by geodetic fault locking." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 379, no. 2196 (March 15, 2021): 20200135. http://dx.doi.org/10.1098/rsta.2020.0135.
Full textAbstract:
Paleo-earthquakes along the Cascadia subduction zone inferred from offshore sediments and Japan coastal tsunami deposits approximated to M9+ and ruptured the entire margin. However, due to the lack of modern megathrust earthquake records and general quiescence of subduction fault seismicity, the potential megathrust rupture scenario and influence of downdip limit of the seismogenic zone are still obscure. In this study, we present a numerical simulation of Cascadia subduction zone earthquake sequences in the laboratory-derived rate-and-state friction framework to investigate the potential influence of the geodetic fault locking on the megathrust sequences. We consider the rate-state friction stability parameter constrained by geodetic fault locking models derived from decadal GPS records, tidal gauge and levelling-derived uplift rate data along the Cascadia margin. We incorporate historical coseismic subsidence inferred from coastal marine sediments to validate our coseismic rupture scenarios. Earthquake rupture pattern is strongly controlled by the downdip width of the seismogenic, velocity-weakening zone and by the earthquake nucleation zone size. In our model, along-strike heterogeneous characteristic slip distance is required to generate margin-wide ruptures that result in reasonable agreement between the synthetic and observed coastal subsidence for the AD 1700 Cascadia Mw∼9.0 megathrust rupture. Our results suggest the geodetically inferred fault locking model can provide a useful constraint on earthquake rupture scenarios in subduction zones. This article is part of the theme issue ‘Fracture dynamics of solid materials: from particles to the globe’.
19
Zhang, Xijun, Liang Huang, Yujie Hou, Bo Wang, Binghan Xue, and Mingsheng Shi. "Study on the Stability of the Geogrids-Reinforced Earth Slope under the Coupling Effect of Rainfall and Earthquake." Mathematical Problems in Engineering 2020 (October 20, 2020): 1–11. http://dx.doi.org/10.1155/2020/5182537.
Full textAbstract:
This paper focuses on understanding the dynamic response problem of flexible wrapped reinforced Earth slope under the coupling effect of earthquake and rainfall; a numerical calculation model of reinforced Earth slope considering the coupling effect of earthquake and rainfall was established. The dynamic response, pore pressure, and tensile stress distribution of the reinforcement under the rainfall before earthquake, the rainfall after the earthquake, and earthquake-rainfall are studied. The results show that the coupling effect of earthquake and rainfall is an influential factor in the dynamic analysis of reinforced Earth slopes, the analysis of which should be paid attention to and researched in the future. The combination of geogrid and soil effectively improves the deformation of the slope and the overall stability, reduces the secondary disaster of the slope, and provides a reference for the seismic construction design of the reinforced Earth slope.
20
Jaaz, Hussein Abad Gazi, Ali Fadhil Naser, Hussam Ali Mohammed, and Ayad Ali Mohammed. "Earthquake Resistance Optimization and Evaluation of Bridge Piers Structural Form and Dimensions Based on Demand to Capacity Ratio and Yielding Points of Force-Displacement." Mathematical Modelling of Engineering Problems 8, no. 6 (December 22, 2021): 945–54. http://dx.doi.org/10.18280/mmep.080614.
Full textAbstract:
The evaluation of structural safety must be taken after each earthquake. The importance losses of life and materials carries the significance of the works in the field of earthquake engineering. The purpose of this study was to optimize and evaluate the earthquake resistance of bridge piers by adopting different cross-section forms and dimensions for bridge supports under earthquake action. Two methods of seismic design were used in the optimization and evaluation process. These methods were demand to capacity ratio (DCR) and yielding point. The results of demand to capacity ratio shown that the values of DCR for all piers forms models were increased when the dimension of pier cross section were increased and the values of DCR became less than 1.0, indicating that the increasing in dimensions leading to rise the capacity of bridge supports to carry the earthquake loads in transverse and longitudinal direction. Comparing with models, solid wall pier form had the lower value of DCR, indicating that solid wall piers were suitable in the design of bridge supports to resist the lateral loads of earthquake and it has enough stiffness and capacity under earthquake action. The results of performance points shown that the yielding points were increased when the dimensions of piers were increased for all piers form in transverse and longitudinal direction. The maximum values were appeared within support No. 1 and support No. 4. Solid wall form of pier had the higher values of yielding points, meaning that this type of piers form had higher seismic capacity and it will resist the earthquake action more than others piers form. This study recommended that to use third model for each pier form in the design of bridges structures to resist the earthquake load. Also this study was recommended to use solid wall piers as supports in construction of bridge structure within areas had earthquake action.
21
Ornthammarath, Teraphan. "Seismic damage to ancient monuments in Chiang Saen (Northern Thailand): implication for historical earthquakes in Golden Triangle area." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 377, no. 2155 (August 19, 2019): 20180255. http://dx.doi.org/10.1098/rsta.2018.0255.
Full textAbstract:
Over the last few decades, three moderate earthquakes (Mw greater than 6.0) occurred in and around the Golden Triangle area (including Myanmar, Thailand and Lao PDR) causing unprecedented damage and loss of lives in the epicentral region. In addition to the damage to modern structures, most heritage structures in Chiang Saen, a major city of the Lan Na kingdom (from the thirteenth to the eighteenth century), were also affected. This work is intended to present observed historical structure damage from recent earthquakes, which could provide evidence for the severity of historical earthquakes from the thirteenth to the eighteenth century. Based on historical records, geological evidence and observed damage to ancient monuments in this historic town, existing heritage stupas and temples constructed since the fourteenth century sustained only minor to moderate damage from these historical earthquakes. Considering the seismic vulnerability of these historical monuments, Chiang Saen might have never been subjected to severe ground shaking greater than MMI intensity VII, similar to the major earthquake in 460 A.D. along the Mae Chan fault, which was responsible for the large-scale liquefaction and inundation of ancient Yonok town. This information could be important for paleoseismological and historical earthquake research to constrain the recurrence interval of major active faults in this area. This article is part of the theme issue ‘Environmental loading of heritage structures’.
22
Mehmood, Tahir, and Muhammad Awais. "Tukey Control Chart for Radon Monitoring in Relation to the Seismic Activity." Mathematical Problems in Engineering 2021 (May 25, 2021): 1–8. http://dx.doi.org/10.1155/2021/9999500.
Full textAbstract:
Radon is one of the precursory phenomena that exist in connection to the occurrence of earthquakes and may have potential in forecasting these hazards. The data set in this study contains the observations of radon from August 01, 2014, to January 31, 2015, collected in Sobra city, northern Pakistan. Weibull, gamma, log-normal, log-logistic, and Pareto probability distribution were fitted over the radon on its original scale and a log scale. Log-logistic best fits the radon on both scales. The Tukey control charts reveal several anomalies that were compared with earthquake occurrence. There are five earthquakes that occurred during the same period as the radon monitoring program, having magnitude ranges between 4.9 and 5.5, with the ratio between strain radius and distance to the epicenter greater than or equal to 1. The results of this study demonstrate that, for earthquakes, seismic events show a correlation with increasing concentrations of radon gas before their occurrence.
23
Zuccaro, G., I. Elishakoff, and A. Baratta. "Antioptimization of earthquake exitation and response." Mathematical Problems in Engineering 4, no. 1 (1998): 1–19. http://dx.doi.org/10.1155/s1024123x98000696.
Full textAbstract:
The paper presents a novel approach to predict the response of earthquake-excited structures. The earthquake excitation is expanded in terms of series of deterministic functions. The coefficients of the series are represented as a point inN-dimensional space. Each available ccelerogram at a certain site is then represented as a point in the above space, modeling the available fragmentary historical data. The minimum volume ellipsoid, containing all points, is constructed. The ellipsoidal models of uncertainty, pertinent to earthquake excitation, are developed. The maximum response of a structure, subjected to the earthquake excitation, within ellipsoidal modeling of the latter, is determined. This procedure of determining least favorable response was termed in the literature (Elishakoff, 1991) as an antioptimization. It appears that under inherent uncertainty of earthquake excitation, antioptimization analysis is a viable alternative to stochastic approach.
24
Kame, Nobuki. "Pre-P gravity signals from dynamic earthquake rupture: modelling and observations." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 379, no. 2196 (March 15, 2021): 20200136. http://dx.doi.org/10.1098/rsta.2020.0136.
Full textAbstract:
Dynamic earthquake rupture is one of the most extensive and devastating fracture phenomena on the Earth. It causes a sudden crustal deformation around a fault and generates seismic waves that induce bulk density variations propagating with them. Both processes constitute rock-mass redistribution, which is expected to induce simultaneous transient gravity perturbations at all distances before the arrival of P-waves. Interest in such pre-P gravity signals has increased both in terms of modelling and observations because of their potential for earthquake early warning. A simple forward model has pioneered the search for the so-called prompt elasto-gravity signals, which led to the first report of a signal from the 2011 M w 9.0 Tohoku-Oki earthquake using a single superconducting gravimeter record. The second report followed using hundreds of broadband seismometers with critical modification of the previous model to consider the pre-P ground acceleration in the measurement of gravity. Post-event analyses have identified prompt elasto-gravity signals from several large earthquakes, and state-of-the-art instruments are now being developed for real-time signal detection. This paper reviews recent progress in the cutting-edge subject of prompt elasto-gravity signals owing to large-scale earthquake rupture. This article is part of the theme issue ‘Fracture dynamics of solid materials: from particles to the globe’.
25
Puzrin, Alexander M., Thierry Faug, and Itai Einav. "The mechanism of delayed release in earthquake-induced avalanches." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 475, no. 2227 (July 2019): 20190092. http://dx.doi.org/10.1098/rspa.2019.0092.
Full textAbstract:
Snow avalanches can be triggered by strong earthquakes. Most existing models assume that snow slab avalanches happen simultaneously during or immediately after their triggering. Therefore, they cannot explain the plausibility of delayed avalanches that are released minutes to hours after a quake. This paper establishes the basic mechanism of delays in earthquake-induced avalanche release using a novel analytical model that yields dynamics consistent with three documented cases, including two from Western Himalaya and one from central Italy. The mechanism arises from the interplay between creep, strain softening and strain-rate sensitivity of snow, which drive the growth of a basal shear fracture. Our model demonstrates that earthquake-triggered delayed avalanches are rare, yet possible, and could lead to significant damage, especially in long milder slopes. The generality of the model formulation opens a new approach for exploring many other problems related to natural slab avalanche release.
26
Tak, Hye-Young, Wonho Suh, and Young-Joo Lee. "System-Level Seismic Risk Assessment of Bridge Transportation Networks Employing Probabilistic Seismic Hazard Analysis." Mathematical Problems in Engineering 2019 (August 25, 2019): 1–17. http://dx.doi.org/10.1155/2019/6503616.
Full textAbstract:
Earthquakes can have significant impacts on transportation networks because of the physical damage they can cause to bridges. Hence, it is essential to assess the seismic risk of a bridge transportation network accurately. However, this is a challenging task because it requires estimating the performance of a bridge transportation network at the system level. Moreover, it is necessary to deal with various possible earthquake scenarios and the associated damage states of component bridges considering the uncertainty of earthquake locations and magnitudes. To overcome these challenges, this study proposes a new method of system-level seismic risk assessment for bridge transportation networks employing probabilistic seismic hazard analysis (PSHA). The proposed method consists of three steps: (1) seismic fragility estimation of the bridges based on PSHA; (2) system-level performance estimation using a matrix-based framework; and (3) seismic risk assessment based on the total probability theorem. In the proposed method, PSHA enables the seismic fragility estimation of the component bridges considering the uncertainty of earthquake locations and magnitudes, and it is systemically used to carry out a posthazard bridge network flow capacity analysis by employing the matrix-based framework. The proposed method provides statistical moments of the network performance and component importance measures, which can be used by decision makers to reduce the seismic risk of a target area. To test the proposed method, it is applied to a numerical example of an actual transportation network in South Korea. In the seismic risk assessment of the example, PSHA is successfully integrated with the matrix-based framework to perform system reliability analysis in a computationally efficient manner.
27
Shahrab, Khalil Arab, and Abuzar Mirzakhani. "Earthquake Risk Analysis and Qualitative Comparison of Attenuation Relationships in Garmsar City, Iran." Journal of Computational and Theoretical Nanoscience 16, no. 12 (December 1, 2019): 5332–46. http://dx.doi.org/10.1166/jctn.2019.8613.
Full textAbstract:
Despite the scientists’ wide efforts to determine earthquake risks all around the world, it is not still possible to predict the exact time, location and magnitude of future earthquakes and aftershocks at the ground surface so precise results are not predictable within near future. The most significant reason for this relates to numerous complexities of earthquake mechanism and causal conditions and waves through different ground layers with completely different properties. Logical tree method was used with weights to determine acceleration spectra due to spectral nature of region. Probabilistic analysis of earthquake hazard was done using SEISRISK III program. The analysis results are proposed through spectral acceleration maps for 50 years in Garmsar. Moreover, uniform hazard spectrum and spectrum with constant shape are presented.
28
Green, Harry W. "Phase-transformation-induced lubrication of earthquake sliding." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 375, no. 2103 (August 21, 2017): 20160008. http://dx.doi.org/10.1098/rsta.2016.0008.
Full textAbstract:
Frictional failure is not possible at depth in Earth, hence earthquakes deeper than 30–50 km cannot initiate by overcoming dry friction. Moreover, the frequency distribution of earthquakes with depth is bimodal, suggesting another change of mechanism at about 350 km. Here I suggest that the change at 30–50 km is from overcoming dry friction to reduction of effective stress by dehydration embrittlement and that the change at 350 km is due to desiccation of slabs and initiation by phase-transformation-induced faulting. High-speed friction experiments at low pressure indicate that exceeding dry friction provokes shear heating that leads to endothermic reactions and pronounced weakening. Higher-pressure studies show nanocrystalline gouge accompanying dehydration and the highest pressure experiments initiate by exothermic polymorphic phase transformation. Here I discuss the characteristic nanostructures of experiments on high-speed friction and high-pressure faulting and show that all simulated earthquake systems yield very weak transformation-induced lubrication, most commonly nanometric gouge or melt. I also show that phase-transformation-induced faulting of olivine to spinel can propagate into material previously transformed to spinel, apparently by triggering melting analogous to high-speed friction studies at low pressure. These experiments taken as a whole suggest that earthquakes at all depths slide at low frictional resistance by a self-healing pulse mechanism with rapid strength recovery. This article is part of the themed issue ‘Faulting, friction and weakening: from slow to fast motion’.
29
Wang, Wei, Yahui Zhang, and Huajiang Ouyang. "Influence of Random Multi-Point Seismic Excitations on the Safety Performance of a Train Running on a Long-Span Bridge." International Journal of Structural Stability and Dynamics 20, no. 04 (April 2020): 2050054. http://dx.doi.org/10.1142/s0219455420500546.
Full textAbstract:
The increasing use of bridges in high-speed railway (HSR) lines raises the possibility of train derailment on bridges under seismic excitations. In this paper, the influence of random multi-point earthquakes on the safe running of a train on a long-span bridge is studied in terms of the dynamic reliability, considering spatial seismic effects, and randomness of ground motions and train locations. The equations of motion for the train and the track/bridge as time-invariant subsystems under earthquakes are established, separately. The two subsystems are connected via the wheel–rail interface, for which a nonlinear contact model and detachment are considered. The time-history samples of nonstationary multi-point random earthquakes considering wave passage effects and incoherence effects are generated by the autoregressive moving average (ARMA) model. The ground motions are imposed on the bridge support points in terms of displacement and velocity. The train location at the time of earthquake is considered a uniformly distributed random variable. The running safety reliability of a train moving on a long-span bridge under earthquakes is determined by combining subset simulation (SS) with a prediction-based iterative solution method. Under different seismic components, train speeds, apparent seismic wave velocities and seismic intensities, the most unfavorable train location intervals are determined, which provides a reference for the safety performance assessment of trains traveling on bridges under earthquakes. Numerical results show that the influence of the lateral seismic component on the wheel derailment coefficient (WDC) is greater than the vertical seismic component, and the earthquake that occurs before the train’s arrival at 70% length of the bridge will significantly reduce its running safety.
30
Lee, Sangmok, Byungmin Kim, and Young-Joo Lee. "Seismic Fragility Analysis of Steel Liquid Storage Tanks Using Earthquake Ground Motions Recorded in Korea." Mathematical Problems in Engineering 2019 (July 15, 2019): 1–15. http://dx.doi.org/10.1155/2019/6190159.
Full textAbstract:
Liquid-containing storage tanks are important structures in industrial complexes. Because earthquake damages to liquid storage tanks can cause structural collapse, fires, and hazardous material leaks, there have been continuous efforts to mitigate earthquake damages using seismic fragility analysis. In this regard, this study focuses on the seismic responses and fragility of liquid storage tanks. First, the characteristics of earthquake ground motions are a critical factor influencing the seismic fragility of structures; thus, this study employs real earthquake records observed in the target area, southeastern Korea, with the earthquake characteristics estimated based on the ratio of peak ground acceleration to peak ground velocity. When a liquid storage tank oscillates during an earthquake, additional forces can impact the tank wall owing to hydrodynamic pressures. Therefore, this study presents a sophisticated finite element (FE) model that reflects the hydrodynamic effect of an oscillating liquid. Another advantage of such an FE model is that detailed structural responses of the entire wall shells can be estimated; this is not possible in simplified lumped mass or surrogate models. Lastly, probabilistic seismic demand models are derived for three critical limit states: elastic buckling, elephant’s foot buckling, and steel yielding. Using the real earthquake ground motion records, constructed FE model, and limit states, a seismic fragility analysis is performed for a typical anchored steel liquid storage tank in Korea. In addition, for comparison purposes, a ring-stiffened model is investigated to derive a seismic fragility curve. The results of the seismic fragility assessment show that elastic buckling is the most vulnerable damage state. In contrast, elephant’s foot buckling and steel yielding indicate relatively severe damage levels. Furthermore, it is observed that ring stiffeners decrease the elastic buckling damage, although there is no practical effect on elephant’s foot buckling and steel yielding in all ground motion intensities.
31
Zheng, Zhi, Xiaolan Pan, and Xu Bao. "Sequential Ground Motion Effects on the Behavior of a Base-Isolated RCC Building." Mathematical Problems in Engineering 2017 (2017): 1–13. http://dx.doi.org/10.1155/2017/3579713.
Full textAbstract:
The sequential ground motion effects on the dynamic responses of reinforced concrete containment (RCC) buildings with typical isolators are studied in this paper. Although the base isolation technique is developed to guarantee the security and integrity of RCC buildings under single earthquakes, seismic behavior of base-isolated RCC buildings under sequential ground motions is deficient. Hence, an ensemble of as-recorded sequential ground motions is employed to study the effect of including aftershocks on the seismic evaluation of base-isolated RCC buildings. The results indicate that base isolation can significantly attenuate the earthquake shaking of the RCC building under not only single earthquakes but also seismic sequences. It is also found that the adverse aftershock effect on the RCC can be reduced due to the base isolation applied to the RCC. More importantly, the study indicates that disregarding aftershocks can induce significant underestimation of the isolator displacement for base-isolated RCC buildings.
32
Cheng, Yin, Jun Du, and Hao Ji. "Multivariate Joint Probability Function of Earthquake Ground Motion Prediction Equations Based on Vine Copula Approach." Mathematical Problems in Engineering 2020 (January 14, 2020): 1–12. http://dx.doi.org/10.1155/2020/1697352.
Full textAbstract:
In the structural earthquake engineering, a single parameter is often not sufficient enough to depict the severity of ground motions, and it is thus necessary to use multiple ones. In this sense, the correlation among multiple parameters is generally considered as an importance issue. The conventional approach for developing the correlation is based on regression analysis, along with simple pair copula approaches proposed in recent years. In this study, an innovative mathematical technique—vine copula—is firstly introduced to develop the empirical model for the multivariate dependence of pseudospectral accelerations (PSAs), which are the most commonly used earthquake ground motion parameters. This advancement not only offers a more flexible way of describing nonlinear dependence among multivariate PSAs from the marginal distribution functions but also highlights the extreme dependence. The results can be conventionally acquired in the ground motion selection and seismic risk and loss assessment based on multivariate parameters.
33
Gao, Lin, Mingzhen Wang, Anshuang Liu, and Huafeng Gong. "Comprehensive Evaluation of Urban Road Network Resilience Facing Earthquakes." Mathematical Problems in Engineering 2021 (April 30, 2021): 1–12. http://dx.doi.org/10.1155/2021/6659114.
Full textAbstract:
The road network’s transport capacity and traffic function will be directly reduced if urban roads are damaged by earthquakes. To effectively improve the resistance and recovery ability of urban road networks facing earthquake disasters, the establishment of an aseismic resilience evaluation method for the urban road network is the research goal. This paper’s novelty introduces the concept of engineering resilience into the aseismic performance evaluation of urban road networks. It reveals the internal influence principle of nodes and independent pathways on the aseismic resilience of the network. This paper’s significant contribution is to establish a reasonable and comprehensive urban road network aseismic resilience evaluation method. This method can realize the calculation of the aseismic resilience for the existing network, reconstruction network, and new network and propose the optimization, transformation, and layout for the network. The MATLAB program for the whole process calculation of aseismic resilience is developed. The overall network’s aseismic resilience is obtained by the sum of the product of the node importance and the average number of the reliable independent pathways.
34
Alati, Natale, Giuseppe Failla, and Felice Arena. "Seismic analysis of offshore wind turbines on bottom-fixed support structures." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 373, no. 2035 (February 28, 2015): 20140086. http://dx.doi.org/10.1098/rsta.2014.0086.
Full textAbstract:
This study investigates the seismic response of a horizontal axis wind turbine on two bottom-fixed support structures for transitional water depths (30–60 m), a tripod and a jacket, both resting on pile foundations. Fully coupled, nonlinear time-domain simulations on full system models are carried out under combined wind–wave–earthquake loadings, for different load cases, considering fixed and flexible foundation models. It is shown that earthquake loading may cause a significant increase of stress resultant demands, even for moderate peak ground accelerations, and that fully coupled nonlinear time-domain simulations on full system models are essential to capture relevant information on the moment demand in the rotor blades, which cannot be predicted by analyses on simplified models allowed by existing standards. A comparison with some typical design load cases substantiates the need for an accurate seismic assessment in sites at risk from earthquakes.
35
Fagereng, Å., and A. Beall. "Is complex fault zone behaviour a reflection of rheological heterogeneity?" Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 379, no. 2193 (February 2021): 20190421. http://dx.doi.org/10.1098/rsta.2019.0421.
Full textAbstract:
Fault slip speeds range from steady plate boundary creep through to earthquake slip. Geological descriptions of faults range from localized displacement on one or more discrete planes, through to distributed shearing flow in tabular zones of finite thickness, indicating a large range of possible strain rates in natural faults. We review geological observations and analyse numerical models of two-phase shear zones to discuss the degree and distribution of fault zone heterogeneity and effects on active fault slip style. There must be certain conditions that produce earthquakes, creep and slip at intermediate velocities. Because intermediate slip styles occur over large ranges in temperature, the controlling conditions must be effects of fault properties and/or other dynamic variables. We suggest that the ratio of bulk driving stress to frictional yield strength, and viscosity contrasts within the fault zone, are critical factors. While earthquake nucleation requires the frictional yield to be reached, steady viscous flow requires conditions far from the frictional yield. Intermediate slip speeds may arise when driving stress is sufficient to nucleate local frictional failure by stress amplification, or local frictional yield is lowered by fluid pressure, but such failure is spatially limited by surrounding shear zone stress heterogeneity. This article is part of a discussion meeting issue ‘Understanding earthquakes using the geological record’.
36
Ai, Hongzhou, Lingkan Yao, Haixin Zhao, and Yiliang Zhou. "Shallow-Water-Equation Model for Simulation of Earthquake-Induced Water Waves." Mathematical Problems in Engineering 2017 (2017): 1–11. http://dx.doi.org/10.1155/2017/3252498.
Full textAbstract:
A shallow-water equation (SWE) is used to simulate earthquake-induced water waves in this study. A finite-difference method is used to calculate the SWE. The model is verified against the models of Sato and of Demirel and Aydin with three kinds of seismic waves, and the numerical results of earthquake-induced water waves calculated using the proposed model are reasonable. It is also demonstrated that the proposed model is reliable. Finally, an empirical equation for the maximum water elevation of earthquake-induced water waves is developed based on the results obtained using the model, which is an improvement on former models.
37
Jin, Congcong, and Shichun Chi. "Seismic Fragility Analysis of High Earth-Rockfill Dams considering the Number of Ground Motion Records." Mathematical Problems in Engineering 2019 (February 12, 2019): 1–12. http://dx.doi.org/10.1155/2019/6958643.
Full textAbstract:
This study analyzes the impact of the number of ground motions on the seismic fragility of a high earth-rockfill dam and the estimation of reasonable fragility parameters based on a sufficient number of earthquake records. In this paper, the vertical deformation is obtained using the three-dimensional finite element program DYNE3WAC combined with the Pastor–Zienkiewicz–Chan model and Biot dynamic consolidation theory. The relative seismic settlement rate is considered the damage index for the seismic fragility analysis of the dam. The fragility curves of the high earth-rockfill dam are determined by the multiple stripe analysis (MSA) method. A set of seismic waves is chosen based on the spectrum in the Chinese hydraulic structure seismic code. With an increasing number of earthquake records, the coefficients of variation (COV) of the mean and standard deviation (STD) of the relative seismic settlement rate decrease and tend to stabilize when the number of earthquake records reaches 34. The estimated fragility parameters θ and β are constant when the number of earthquake records exceeds 34. The requisite number of earthquake records for an accurate fragility estimation is determined by analyzing the lower and upper confidence intervals for the estimated θ and β. The 95% and 90% confidence interval can accurately estimate the fragility of a high earth-rockfill dam when the number of ground motion records reaches 36 and 32, respectively. The results of the fragility analysis demonstrate that the DYNE3WAC program and MSA method can provide an effective basis for determining fragility curves. Furthermore, the sensitivity analysis of earthquake records is essential for assessing the seismic fragility of high earth-rockfill dams.
38
Kreinovich, Vladik, David Nemir, and Efren Gutierrez. "Applications of interval computations to earthquake-resistant engineering: How to compute derivatives of interval functions fast." Reliable Computing 1, no. 2 (June 1995): 141–72. http://dx.doi.org/10.1007/bf02384052.
Full text
39
Darmi, Yulia, Busono Soerowirdjo, Ery Prasetyo Wibowo, and Ernastuti. "Information System for Determining Earthquake and Tsunami Evacuation Paths in Bengkulu City Based on Android." Journal of Computational and Theoretical Nanoscience 16, no. 12 (December 1, 2019): 5180–85. http://dx.doi.org/10.1166/jctn.2019.8583.
Full textAbstract:
Facility of directions to the evacuation places in the city of Bengkulu is very minimal, so that people are very difficult to find an efficient route to the evacuation places. The problem is how to determine the evacuation route/gathering point. Indonesia is prone to earthquakes because logically, the Indonesian archipelago is at the confluence of three tectonic plates: the Eurasian plate, the Australian plate and the Pacific plate. In the event of an earthquake and tsunami disaster, if disaster preparedness is not prepared, it will cause damage to buildings, offices and can result in fatalities such as the events in Nangro Aceh Darussalam. Therefore, we need a system that can help overcome this disaster management. The system that can be made is the Information System for Determining Earthquake and Tsunami Evacuation Paths in the city of Bengkulu Using Android. By using Android, it will be easier for people to imitate an evacuation route or place during an earthquake and tsunami.
40
Landes, M., J. R. R. Ritter, and U. Wedeken. "Weighing earthquake waves." Measurement 42, no. 1 (January 2009): 13–17. http://dx.doi.org/10.1016/j.measurement.2008.03.012.
Full text
41
Ummati, Alfinna Mahya, Chih-Shian Chen, Ren-Zuo Wang, and Chung-Yue Wang. "Analysis of general functional bearing model in a single-span bridge to identify structure response and suitable friction coefficient under near- and far-fault earthquakes." Journal of Mechanics 38 (2022): 491–508. http://dx.doi.org/10.1093/jom/ufac041.
Full textAbstract:
ABSTRACT Analysis of a single-span bridge with rubber bearing as the isolation system is performed under earthquakes. The conventional bridge seismic design requires the whole structure to be perfectly connected to avoid interrupting the transfer of earthquake energy from the ground through the bridge. A bridge with this typical design requires a high-cost construction due to the need for a huge section of the bridge to resist the earthquake force demand. Thus, many bridges in Taiwan are designed with a rubber bearing only put in between the column and girder without an anchor system. Thus, the bridge movement by rubber displacement is permissible, but the sliding displacement must be accommodated to limit the movement. The sliding displacement is the method to exploit the friction force provided by the sliding on the top and bottom interface of the rubber with the girder and column to dissipate the earthquake input energy transmitted to the structure. By involving the role of surface friction, the shear force transmitted to the structure can be reduced and the bridge performance optimized. General Functional Bearing Model (GFBM) analysis is a rubber bearing analysis which unmerges the function of friction and restoring force. In contrast with the conventional method, the rubber bearing designed with GFBM analysis may reduce the bridge stiffness and deck acceleration, and it is more convenient because only sliding displacement needs to be controlled. This research proposed GFBM analysis to simulate the rubber bearing that is reflected in the real conditions of bridges in Taiwan.
42
Kang, Xiaofang, Peipei Zhang, Yiwei Zhang, Dawei Man, Qinghu Xu, Xianzeng Shi, Yu Zhang, and Guanghui Xia. "Decentralized Control Strategies of Adjacent Building Structures Vibration under Earthquake Excitation." Mathematical Problems in Engineering 2021 (April 26, 2021): 1–14. http://dx.doi.org/10.1155/2021/9964019.
Full textAbstract:
A decentralized control scheme can effectively solve the control problem of civil engineering structure vibration under earthquake. This paper takes a research into the decentralized control scheme of adjacent buildings when the earthquake happens. It combines overlapping decentralized control method and linear matrix inequality (LMI) with H ∞ control algorithm and puts forward the overlapping decentralized H ∞ control method. A simplified dynamical model of structural vibration control has been established considering the topology structural features of adjacent buildings. The H ∞ control algorithm is applied into each dynamically different subsystems and can be also served as the decentralized H ∞ controllers. Therefore, by contracting decentralized H ∞ controllers to original state space, overlapping decentralized H ∞ controllers are obtained. In this manner, the adjacent buildings’ structure model is analyzed in terms of simulation and calculation which provides a comprehensive insight into vibration control. The results show that the centralized control, the decentralized control, and the overlapping decentralized control, based on linear matrix inequality, can be nearly effective in cases above satisfactorily. Besides, it can also reduce the computational cost as well as increase the flexibility of controller design.
43
Sieh, Kerry. "Sumatran megathrust earthquakes: from science to saving lives." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 364, no. 1845 (June 26, 2006): 1947–63. http://dx.doi.org/10.1098/rsta.2006.1807.
Full textAbstract:
Most of the loss of life, property and well-being stemming from the great Sumatran earthquake and tsunami of 2004 could have been avoided and losses from similar future events can be largely prevented. However, achieving this goal requires forging a chain linking basic science—the study of why, when and where these events occur—to people's everyday lives. The intermediate links in this chain are emergency response preparedness, warning capability, education and infrastructural changes. In this article, I first describe our research on the Sumatran subduction zone. This research has allowed us to understand the basis of the earthquake cycle on the Sumatran megathrust and to reconstruct the sequence of great earthquakes that have occurred there in historic and prehistoric times. On the basis of our findings, we expect that one or two more great earthquakes and tsunamis, nearly as devastating as the 2004 event, are to be expected within the next few decades in a region of coastal Sumatra to the south of the zone affected in 2004. I go on to argue that preventing future tragedies does not necessarily involve hugely expensive or high-tech solutions such as the construction of coastal defences or sensor-based tsunami warning systems. More valuable and practical steps include extending the scientific research, educating the at-risk populations as to what to do in the event of a long-lasting earthquake (i.e. one that might be followed by a tsunami), taking simple measures to strengthen buildings against shaking, providing adequate escape routes and helping the residents of the vulnerable low-lying coastal strips to relocate their homes and businesses to land that is higher or farther from the coast. Such steps could save hundreds and thousands of lives in the coastal cities and offshore islands of western Sumatra, and have general applicability to strategies for helping the developing nations to deal with natural hazards.
44
Jackson, James, Dan McKenzie, and Keith Priestley. "Relations between earthquake distributions, geological history, tectonics and rheology on the continents." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 379, no. 2193 (February 2021): 20190412. http://dx.doi.org/10.1098/rsta.2019.0412.
Full textAbstract:
This paper is concerned with the distribution of earthquakes, particularly their depths, with the temperature of the material in which they occur, and with the significance of both for the rheology and deformation of the continental lithosphere. Earthquakes on faults are generated by the sudden release of elastic energy that accumulates during slow plate motions. The nonlinear high-temperature creep that localizes such energy accumulation is, in principle, well understood and can be described by rheological models. But the same is not true of seismogenic brittle failure, the main focus of this paper, and severely limits the insights that can be obtained by simulations derived from geodynamical modelling of lithosphere deformation. Through advances in seismic tomography, we can now make increasingly detailed maps of lithosphere thickness on the continents. The lateral variations are dramatic, with some places up to 300 km thick, and clearly relate to the geological history of the continents as well as their present-day deformation. Where the lithosphere thickness is about 120 km or less, continental earthquakes are generally confined to upper crustal material that is colder than about 350°C. Within thick lithosphere, and especially on its edges, the entire crust may be seismogenic, with earthquakes sometimes extending into the uppermost mantle if the Moho is colder than 600°C, but the continental mantle is generally aseismic. Earthquakes in the continental lower crust at 400–600°C require the crust to be anhydrous and so are a useful guide or proxy to both composition and strength. These patterns and correlations have important implications for the geological evolution of the continents. They can be seen to have influenced features as diverse as the location of post-collisional rifting; cratonic basin formation; the location, origin and timing of granulite-facies metamorphism; and the formation, longevity and strength of cratons. In addition, they have important consequences for earthquake hazard assessment in the slowly deforming edges and interiors of continental shields or platforms, where the large seismogenic thickness can host very large earthquakes. This article is part of a discussion meeting issue ‘Understanding earthquakes using the geological record'.
45
Itoh, Ryo, and Takahiro Hatano. "Geological implication of grain-size segregation in dense granular matter." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 377, no. 2136 (November 26, 2018): 20170390. http://dx.doi.org/10.1098/rsta.2017.0390.
Full textAbstract:
To the current common belief, grain size segregation in granular matter requires sufficient porosity. Therefore, grain size segregation found in a natural fault gouge could imply elevated fluid pressure and the reduced normal stress on fault, possibly caused by the frictional heat during an earthquake. To clarify whether fluidization is essential to grain size segregation, we conduct numerical simulation on a simple model of fault gouge in a plane shear geometry under constant volume condition: the volume fraction is fixed at 0.6, at which the granular system possesses yield stress. We observe apparent grain size segregation at this volume fraction, meaning that grain size segregation alone does not imply fluidization of granular matter. We also show that segregation is driven by the nonlinear velocity profile, and that the gravity is not essential to segregation. The physical condition tested here may be relevant to earthquake faults: the normal stress of 1 MPa, the sliding velocity of 1 m s −1 , and the duration of 0.1 s. This article is part of the theme issue ‘Statistical physics of fracture and earthquakes’.
46
Shah, Haresh C. "The last mile: earthquake risk mitigation assistance in developing countries." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 364, no. 1845 (June 27, 2006): 2183–89. http://dx.doi.org/10.1098/rsta.2006.1821.
Full textAbstract:
Over the past few decades, we have seen many joint programmes between developed countries and developing countries to help the latter in managing their earthquake risks. These programmes span the whole spectrum of disciplines from seismology and geology to engineering, social science and economics. Many of these programmes have been effective in raising awareness, in urging governments to work towards risk reduction and in spawning an ‘industry’ of disaster management in many of the developing countries. However, even as these efforts proceed, we have seen death and destruction due to earthquake after earthquake in developing countries, strongly suggesting that the problems for which those assistance programmes were developed are not so effective. Therefore, it is natural to ask why this is happening. Are the assistance programmes reaching the right people? Maybe we are reaching the right people and doing the right type of things in these countries, but we have not allowed enough time for our actions to take effect. Maybe we are reaching the right people and doing the right actions for most of the miles we need to cover in helping communities mitigate their earthquake risks. However, the issue could be whether we are reaching people who represent the ‘last mile’ on this pathway. Here, I explore whether the work that many organizations and countries have done towards earthquake risk reduction over the past few decades in developing countries is appropriate or not. Why do we keep seeing the catastrophes of Sumatra, Chi Chi, Bhuj, Turkey, Algeria and on and on? I will articulate what I think is the problem. My contribution is intended to generate discussions, self-analysis of our approaches, what we are doing right and what we are not doing right. Hopefully such discussions will result in a better connection between the last mile and programmes around the world which are working towards earthquake risk mitigation.
47
Kovačević, Andjelka B., Aleksandra Nina, Luka Č. Popović, and Milan Radovanović. "Two-Dimensional Correlation Analysis of Periodicity in Noisy Series: Case of VLF Signal Amplitude Variations in the Time Vicinity of an Earthquake." Mathematics 10, no. 22 (November 15, 2022): 4278. http://dx.doi.org/10.3390/math10224278.
Full textAbstract:
Extraction of information in the form of oscillations from noisy data of natural phenomena such as sounds, earthquakes, ionospheric and brain activity, and various emissions from cosmic objects is extremely difficult. As a method for finding periodicity in such challenging data sets, the 2D Hybrid approach, which employs wavelets, is presented. Our technique produces a wavelet transform correlation intensity contour map for two (or one) time series on a period plane defined by two independent period axes. Notably, by spreading peaks across the second dimension, our method improves the apparent resolution of detected oscillations in the period plane and identifies the direction of signal changes using correlation coefficients. We demonstrate the performance of the 2D Hybrid technique on a very low frequency (VLF) signal emitted in Italy and recorded in Serbia in time vicinity of the occurrence of an earthquake on 3 November 2010, near Kraljevo, Serbia. We identified a distinct signal in the range of 120–130 s that appears only in association with the considered earthquake. Other wavelets, such as Superlets, which may detect fast transient oscillations, will be employed in future analysis.
48
Xiong, Xiaowen, Fan Zhao, Yundou Wang, and Yapeng Wang. "Research on the Model and Algorithm for Multimodal Distribution of Emergency Supplies after Earthquake in the Perspective of Fairness." Mathematical Problems in Engineering 2019 (January 3, 2019): 1–12. http://dx.doi.org/10.1155/2019/1629321.
Full textAbstract:
After the earthquake, it is important to ensure the emergency supplies are provided in time. However, not only the timeliness, but also the fairness from different perspectives should be considered. Therefore, we use a multilevel location-routing problem (LPR) to study the fairness of distribution for emergency supplies after earthquake. By comprehensively considering the time window constraints, the partial road damage and dynamic recovery in emergency logistics network, the stochastic driving time of the vehicle, and the mixed load of a variety of emergency materials, we have developed a multiobjective model for the LRP in postearthquake multimodal and fair delivery of multivariety emergency supplies with a limited period. The goal of this model is to minimize the total time in delivering emergency supplies and to minimize the maximum waiting time for emergency supplies to reach demand points. A hybrid heuristic algorithm is designed to solve the model. The example shows that this algorithm has a high efficiency and can effectively realize the supply of emergency supplies after the earthquake within the specified period. This method might be particularly suitable for the emergency rescue scenarios where the victims of the earthquake are vulnerable to mood swings and the emergency supplies need to be fairly distributed.
49
Rice, James R. "Heating, weakening and shear localization in earthquake rupture." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 375, no. 2103 (August 21, 2017): 20160015. http://dx.doi.org/10.1098/rsta.2016.0015.
Full textAbstract:
Field and borehole observations of active earthquake fault zones show that shear is often localized to principal deforming zones of order 0.1–10 mm width. This paper addresses how frictional heating in rapid slip weakens faults dramatically, relative to their static frictional strength, and promotes such intense localization. Pronounced weakening occurs even on dry rock-on-rock surfaces, due to flash heating effects, at slip rates above approximately 0.1 m s −1 (earthquake slip rates are typically of the order of 1 m s −1 ). But weakening in rapid shear is also predicted theoretically in thick fault gouge in the presence of fluids (whether native ground fluids or volatiles such as H 2 O or CO 2 released by thermal decomposition reactions), and the predicted localizations are compatible with such narrow shear zones as have been observed. The underlying concepts show how fault zone materials with high static friction coefficients, approximately 0.6–0.8, can undergo strongly localized shear at effective dynamic friction coefficients of the order of 0.1, thus fitting observational constraints, e.g. of earthquakes producing negligible surface heat outflow and, for shallow events, only rarely creating extensive melt. The results to be summarized include those of collaborative research published with Nicolas Brantut (University College London), Eric Dunham (Stanford University), Nadia Lapusta (Caltech), Hiroyuki Noda (JAMSTEC, Japan), John D. Platt (Carnegie Institution for Science, now at *gramLabs), Alan Rempel (Oregon State University) and John W. Rudnicki (Northwestern University). This article is part of the themed issue ‘Faulting, friction and weakening: from slow to fast motion’.
50
Barés, Jonathan, and Daniel Bonamy. "Crack growth in heterogeneous brittle solids: intermittency, crackling and induced seismicity." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 377, no. 2136 (November 26, 2018): 20170386. http://dx.doi.org/10.1098/rsta.2017.0386.
Full textAbstract:
Crack growth is the basic mechanism leading to the failure of brittle materials. Engineering addresses this problem within the framework of continuum mechanics, which links deterministically the crack motion to the applied loading. Such an idealization, however, fails in several situations and in particular cannot capture the highly erratic (earthquake-like) dynamics sometimes observed in slowly fracturing heterogeneous solids. Here, we examine this problem by means of innovative experiments of crack growth in artificial rocks of controlled microstructure. The dynamical events are analysed at both global and local scales, from the time fluctuation of the spatially averaged crack speed and the induced acoustic emission, respectively. Their statistics are characterized and compared with the predictions of a recent approach mapping fracture onset to the depinning of an elastic interface. Finally, the overall time–size organization of the events is characterized to shed light on the mechanisms underlying the scaling laws observed in seismology. This article is part of the theme issue ‘Statistical physics of fracture and earthquakes’.