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Cho, Gye Chun. "Unsaturated soil stiffness and post-liquefaction shear strength." Diss., Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/21010.
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Mayfield, Roy T. "The return period of soil liquefaction /." Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/10209.
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GUILLEN, JORGE LUIS CARDENAS. "ELASTO-PLASTICITY MODELLING OF SOIL LIQUEFACTION." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2008. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=25812@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
Mudanças das propriedades dos solos devido à ação de carregamentos dinâmicos são responsáveis por danos significativos em geo-estruturas, tais como: barragens, estruturas de concentração, fundações, taludes, etc. A ocorrência do fenômeno da liquefação, em materiais suscetíveis como areias fofas saturadas, representa um tipo de resposta desastrosa de solos. O termo liquefação tem sido empregado para descrever uma variedade de fenômenos no qual tem em comum o desenvolvimento de altas poropressões em materiais saturados sem coesão devido a carregamentos monotônicos , transientes ou ciclios. A previsão da liquefação depende de uma adequada análise do comportamento não-drenado do material, em termos do incremento de poropressões e da perda da rigidez da mistura sólido-fluido, durante e após o período de movimento. O estabelecimento das equações governantes é essencial para elaboração de um modelo matemático realista para descrever o comportamento físico deste fenômeno. As equações a srem consideradas são: equação de movimento da fase sólida, a equação do movimento da mistura sólido-fluido , a equação de continuidade da fase fluida, as equações de acoplamento das fases e as equações constitutivas desses materiais. Nesta tese a resposta dinâmica do solo foi investigada numericamente mediante a técnica dos elementos finitos. A discretização espacial das equações governantes foi feita através de método de Galerkin e a discretização temporal pelo método de Newmark Generalizado. Um modelo constitutivo elasto-plástico foi considerado para descrever o comportamento mecânico da fase sólida, desenvolvido a partir de conceitos da generealização da teoria da plasticidade, que apresenta algumas vantagens em relação aos outros modelos baseados na teoria da plasticidade clássica. A implementação computacional foi escrito em fortran 90. Exemplos numéricos analisados nesta tese comprovam tanto a eficiência do modelo constitutivo na predição do comportamento do solo sobre liquefação como a confiabilidade do programa computacional elaborado nesta pesquisa, em termos da rapidez de processamento e da boa precisão dos resultados, quando comparados com soluções analíticas e outros valores numéricos obtidos por vários autores e diferentes modelos constitutivos.
Changes in soil properties due to the action of dynamic loads are responsible for significant damage of geo-structures such as dams, retaining structures,building foundations, slopes, etc. The occurrence of liquefaction phenomena in susceptible materials, such as loose saturated, represents a type of disastrous response of soil, the term liquefaction has been used to refer to a group of phenomena wich have in common the development of high pore pressures in saturated cohesionless mterial due to monotonic, transient, or cyclic loads. The prediction of soil liquefaction depends of an adequate analysis of the behavior of undrained materials, in terms of increase of pore water pressure and weakening of the solid-fluid mixture, during and after the periodic motion. The establishment of the governing equations is essential to provide a realistic mathematical model to describe the physical behavior of this phenomenon. The system of equations to be considered are: the equilibrium equation of the solid phase, the equilibrium equation of the solid-fluid mixture, the conservation mass of the fluid phase, the coupling equation of phases, and the conservation equations of materials. In this thesis the soil dynamic response was numerically investigated by the finite element method. To obtain the spatial discretization in time was the Generalized Newmark method. An elastic-plastic constitutive model was used to describe the mechanical behavior of the solid phase. This model was developed in the framework of the generalized theory of plasticity, wich has some advantages when compared with other models based on the classical plasticity theory. The computacional implementation was written in fortran 90. Numerical examples considered in this thesis demonstrate the efficiency of the constitutive model to simulated the predicted behavior of soil under liquefaction as well as the reliability of the software developed in this research, in terms of computational effort and good accuracy of the results, when compared with some analytical solutions and other numerical values obtained by various authors and different constitutive models.
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Song, Chi-Yong. "Numerical formulation for a dynamic analysis of the plastic behavior in saturated granular soils." Columbus, Ohio Ohio State University, 2003. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1070309764.
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Thesis (Ph. D.)--Ohio State University, 2003.Title from first page of PDF file. Document formatted into pages; contains xix, 246 p.; also includes graphics. Includes abstract and vita. Advisor: William E. Wolfe, Dept. of Civil Engineering. Includes bibliographical references (p. 137-142).
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Worthen, Diana. "Critical state framework and liquefaction of fine-grained soils." Pullman, Wash. : Washington State University, 2009. http://www.dissertations.wsu.edu/Thesis/Summer2009/D_Worthen_062209.pdf.
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Thesis (M.S. in civil engineering)--Washington State University, August 2009.Title from PDF title page (viewed on Aug. 10, 2009). "Department of Civil and Environmental Engineering." Includes bibliographical references (p. 45-46).
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Adalier, Korhan. "Mitigation of earthquake induced liquefaction hazards." online access from Digital Dissertation Consortium access full-text, 1996. http://libweb.cityu.edu.hk/cgi-bin/er/db/ddcdiss.pl?9635658.
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Chung, Jae-Won. "Development of a geographic information system-based virtual geotechnical database and assessment of liquefaction potential for the St. Louis Metropolitan area." Diss., Rolla, Mo. : University of Missouri-Rolla, 2007. http://scholarsmine.mst.edu/thesis/pdf/Chung_09007dcc80483011.pdf.
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Thesis (Ph. D.)--University of Missouri--Rolla, 2007.Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed March 24, 2008) Includes bibliographical references (p. 145-155).
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Daftari, Abbas. "New approach in prediction of soil liquefaction." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2015. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-192304.
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Liquefaction is the phenomena when there is loss of strength in saturated and cohesion-less soils because of increased pore water pressures and hence reduced effective stresses due to dynamic loading. It is a phenomenon in which the strength and stiffness of a soil is reduced by earthquake shaking or other rapid loading.
In this study, after the short review of liquefaction definition, the models of prediction and estimation of liquefaction were considered. Application of numerical modelling with two major software (FLAC & PLAXIS) for the Wildlife site liquefaction, under superstition earthquake in 1987 were compared and analysed.
Third step was started with introduction of Fuzzy logic and neural network as two common intelligent mathematical methods. These two patterns for prediction of soil liquefaction were combined. The “Neural network- Fuzzy logic-Liquefaction- Prediction” (NFLP) was applied for liquefaction prediction in Wildlife site. The results show the powerful prediction of liquefaction happening with high degree of accuracy in this case.
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Bradshaw, Aaron S. "Liquefaction potential of non-plastic silts /." View online ; access limited to URI, 2006. http://0-digitalcommons.uri.edu.helin.uri.edu/dissertations/AAI3248224.
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Anderson, Donald Jared. "Understanding Soil Liquefaction of the 2016 Kumamoto Earthquake." BYU ScholarsArchive, 2019. https://scholarsarchive.byu.edu/etd/7135.
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The Kumamoto earthquake of April 2016 produced two foreshocks of moment magnitude 6.0 and 6.2 and a mainshock of 7.0, which should have been followed by widespread and intense soil liquefaction. A Geotechnical Extreme Events Reconnaissance team (GEER) led by Professor Rob Kayen of UC Berkley was dispatched to the Kumamoto Plain--which is in Kumamoto Prefecture, the southern main island of Japan--immediately following the earthquake. The Japanese and U.S. engineers in the GEER team observed mostly minor and sporadic liquefaction, which was unexpected as the local site geology, known soil stratigraphy, and intensity of the seismic loading made the Kumamoto Plain ripe for soil liquefaction. The paucity and limited scale of liquefaction shows a clear gap in our understanding of liquefaction in areas with volcanic soils. This study is a direct response to the GEER team's preliminary findings regarding the lack of significant liquefaction. An extensive literature review was conducted on the Kumamoto Plain and its volcanic soil. The liquefaction of the 2016 Kumamoto Earthquake was also researched, and several sites were selected for further analysis. Four sites were analyzed with SPT, CPT, and laboratory testing during the spring of 2017. A slope stability analysis and undisturbed testing were performed for specific sites. The results of the analysis show a general over-prediction of SPT and CPT methods when determining liquefaction hazard. The Youd et al. (2001) NCEES method was the most consistent and accurate in determining liquefaction. The soils in the area including sands and gravels had high levels of fines, plasticity, and organic matter due to the weathering of volcanic ash and pyroclastic material. The volcanically derived coarse-grained soils may also have exhibited some crushability, which gave lower resistance readings. Filled river channels had the worst liquefaction with natural levees and the Kumamoto flood plains having only minor liquefaction. Publicly available boring logs rarely showed laboratory test data of bore holes which led to a general inaccurate soil classification. Boring logs were also not updated with laboratory classifications and data. Undisturbed cyclic triaxial testing of soils at one site showed that volcanic soils had relatively high resistance to soil liquefaction, though drying of samples may have compromised the results. Embankment cracking at one test location was calculated a lateral spread and a seismic slope failure along the pyroclastic flow deposit.
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Jones, Allen L. "An analytical model and applications for ground surface effects from liquefaction /." Thesis, Connect to this title online; UW restricted, 2003. http://hdl.handle.net/1773/10100.
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Chern, Jin-Ching. "Undrained response of saturated sands with emphasis on liquefaction and cyclic mobility." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/25547.
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An experimental investigation of the undrained monotonic and cyclic loading behaviour of a saturated angular sand and a rounded sand under triaxial conditions is presented. These studies are aimed at obtaining a unified approach to the undrained behaviour of sand spanning from strain softening (termed liquefaction or limited liquefaction) to strain hardening
response and linking the cyclic loading behaviour to the monotonic loading behaviour. It is also aimed at investigating the differences In undrained loading behaviour of sand with different particle angularity.
Under monotonic loading, the strain softening response is initiated and terminated at two distinct values of effective stress ratio termed critical effective stress ratio state (CSR) and phase transformation state (PT), regardless of the relative density and consolidation stress conditions. For strain hardening response, the start of dilation also occurs at the same effective stress ratio of PT for strain softening response. It is shown that the unique steady state line concept for liquefaction is also valid for limited liquefaction. The PT states for strain hardening response, however, form a series of lines, which are function of Initial void ratio, merging into the unique steady state line as the consolidation stresses increase.
A 3-D effective stress state behavioural model is developed, which enables prediction of the anticipated undrained loading behaviour (strain softening or strain hardening) from the knowledge of the initial state of the sand. It is shown that a complete specifications of initial state of sand, i.e., void ratio, confining pressure and static shear, is required to predict the type of undrained response, especially for angular sand. Under cyclic loading, if liquefaction develops, the CSR, effective stress ratio at PT state and steady state line are the same as those observed under monotonic loading. If cyclic mobility develops, the effective stress ratio at PT state is also the same as that observed under monotonic loading. Thus, the 3-D effective stress state diagram provides a link between monotonic and cyclic loading behaviour, and is used to develop the criteria for the occurrence of liquefaction and cyclic mobility. The influences of void ratio and confining pressure on the cyclic loading behaviour are similar to those for the monotonic loading behaviour. However, the influence of static shear on cyclic loading behaviour can be completely different depending on whether liquefaction or cyclic mobility is developed. The undrained loading behaviour of rounded sand is similar to that of the angular sand. However, for the range of consolidation stresses of interest, the initial relative density alone provides a good single parameter characterizing the initial state of the sand, and hence its anticipated
response.Applied Science, Faculty of
Civil Engineering, Department of
Graduate
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Lee, Wayne Y. "Numerical modeling of blast-induced liquefaction /." Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1431.pdf.
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Stringer, Mark. "The axial behaviour of piled foundations in liquefiable soil." Thesis, University of Cambridge, 2012. https://www.repository.cam.ac.uk/handle/1810/243637.
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Understanding the mechanisms by which any engineering structure resists load is an essential requirement for its consistent and reliable design. The axial resistance which can be mobilised by piled foundations in liquefiable soils when subjected to strong shaking remains highly uncertain, and a number of piled foundations have failed in strong earthquakes as recently as 2011 . The lack of visible foundation distress in many such cases indicates that failure can occur as a result of the loss of axial capacity during an earthquake, as opposed to the laterally-dominated failure modes which have been the focus of the research community for the last 20 to 30 years. In this thesis, a series of dynamic centrifuge experiments have been carried out to establish how the distribution of axial loads along the length of a pile changes during a strong earthquake. In each test, a 2 × 2 pile group was installed such that its tips were embedded in a dense sand layer which was overlain by liquefiable soil. The tests examine the effects arising from the hydraulic conductivity in the bearing layer, the influence of axial pile cap support and finally whether there are any differences in the behaviour of nominally jacked or bored piles under seismic loading. The pile cap has been shown to play a substantial role in supporting axial loads during strong shaking. In cases where the pile cap was unable to support axial load, the majority of the axial loading was carried as pile end bearing, with some shaft friction being mobilised in both the liquefiable and bearing soil layers as a result of relative lateral displacements between the soil and pile. However, where the pile cap is able to support axial loads, the settlement of the pile cap into the soil led to a dramatic transfer of axial load away from the piles and onto the pile cap. These results imply that where substantial excess pore pressures may be generated at the depth of the pile tip, then the pile caps must be able to support significant axial load. The increased effective stresses below the pile cap were responsible for the mobilisation of shaft friction on the section of pile within the liquefiable layer. However, these piles were unable to mobilise shaft friction in the bearing layer due to the reduced lateral loading on the piles. The axial behaviour of the piled foundations after the end of strong shaking is affected by the recovery of pile end bearing capacity and is therefore strongly dependent on the hydraulic conductivity of the bearing layer. The axial behaviour of nominally bored and jacked pile groups in liquefiable soil deposits are very different under seismic excitation, with the installation process of the latter substantially altering the soil conditions around the tips of the pile, such that in contrast to the bored pile groups, the jacked pile groups did not accumulate settlements until significantly after the strong shaking had commenced. These results imply that the method of installation is an important factor in the seismic response of a foundation, and may be more pronounced for real earthquakes where the number of strong shaking cycles may be more limited than those simulated in the experiments.
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Rahman, Md Mizanur Engineering & Information Technology Australian Defence Force Academy UNSW. "Modelling the influence of fines on liquefaction behaviour." Publisher:University of New South Wales - Australian Defence Force Academy. Engineering & Information Technology, 2009. http://handle.unsw.edu.au/1959.4/43920.
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Traditionally, void ratio, e has been used as a state variable for predicting the liquefaction behaviour of soils under the Critical State (Steady State) framework. Recent publications show that void ratio, e may not be a good parameter for characterizing sand with fines as the steady state, SS data points move downward in e-log(p) space up to certain fines content termed as threshold fines content, TFC. Thus, it was difficult to apply SS concept on sand with fines as a small variation of fines content may lead to different SS line. Many researchers proposed to used equivalent granular void ratio, e* as an alternative state variable (i.e. in lieu of void ratio, e) in attempt to obtain a narrow trend line for SS data points irrespective of fc provided fc TFC. The e* is obtained from e. For the conversion from e to e*, one need a parameter b which presents the active fraction of fines in overall force structure of sand. However, predicting the b is problematic. Most, if not all, of the b reported were determined by case-specific back-analysis, that is, the b-value was selected so that the test results for a given sand-fines type could be correlated with the equivalent granular void ratio, e* irrespective of fines content. This thesis examines the factors that affecting the b value by examining published work on binary packing. This leads to a simple semi-empirical equation for predicting the value of b based onparticle size ratio, and fines content, fc. Published data and experimental results on Sydney sand appears to be in support of the proposed equation. The single relation of SS data points in e*-log(p) space for sand with fines is referred as Equivalent Granular Steady State Line, EG-SSL. The EG-SSL is then used to define the equivalent granular state parameter,*. A good correlation observed between * and q-p, q- q responses in undrained shearing. The e* and * are also used to modified a state dependent constitutive model. Seven model input parameters are needed in addition four to critical state input parameters. These parameters are obtained from drained test. The model is used to predict q-pand q- q responses for flow, non-flow and limited flow behaviour for 0% to 30% fines contents. The model predictions are in good agreement with experimental results. The effect of fines types (in terms of plasticity and angularity) on the prediction equation of b are also examined with four different types of fines. A negligible effect of fines type on the prediction equation of b is observed. The link between monotonic and cyclic loading behaviour for sand with fines are also examined with emphasis on cyclic instability and strain hardening behaviour after quasi steady state, QSS for a range of fines contents (provided that fc < TFC). It is found that a single set of rules could be used to correlate monotonic and cyclic behaviour for a range of fines contents at same *.
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Sze, Hon-yue, and 施漢裕. "Initial shear and confining stress effects on cyclic behaviour and liquefaction resistance of sands." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B45700837.
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Wise, Craig M. "Development of a prototype piezovibrocone penetrometer for in-situ evaluation of soil liquefaction susceptibility." Thesis, Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/20220.
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Ramirez, Jose Manuel. "Influence of soil permeability on liquefaction-induced lateral pile response." Diss., [La Jolla] : University of California, San Diego, 2010. http://wwwlib.umi.com/cr/ucsd/fullcit?p1474550.
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Thesis (M.S.)--University of California, San Diego, 2010.Title from first page of PDF file (viewed March 31, 2010). Available via ProQuest Digital Dissertations. Includes bibliographical references (p. 71-73).
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Brennan, Andrew John. "Vertical drains as a countermeasure to earthquake-induced soil liquefaction." Thesis, University of Cambridge, 2004. https://www.repository.cam.ac.uk/handle/1810/284036.
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Earthquake-induced soil liquefaction is a major cause of damage that needs to be controlled by engineers. A popular option for protecting against liquefaction is the installation of gravel drains to relieve generated excess pore pressures. A series of centrifuge tests were carried out on level sand beds without surface structures, to investigate qualitatively the effect of changing drain parameters and the geometry of drain groups. Using these, it was possible to determine a time varying extent of drain effectiveness, and a zone of influence consisting of a conical volume of soil from which draining fluid left the ground via the drain. Increasing drain radius was seen to increase the size of this zone but not accelerate drainage time if no other drains were near. It was also seen that fluid draining from depth caused a delay in the time for near-surface soil to begin draining. Limiting the influx of fluid from regions which are not to be protected was seen to be crucial to the success of small groups of drains. Soil with low permeability fine layers at the surface had identical pore pressure response to equivalent layers without such layers. However, the quantity of ejection features were greatly reduced by the presence of drains. To aid the modelling of deeper soil deposits, a new deep dynamic centrifuge container was designed and built. Analysis of the final box demonstrated that boundary interaction still occurred when the tested soil deviated from that for which it was designed. Drains were seen to be a temperamental method of achieving liquefaction protection, requiring very careful thought if excess pore pressures are to be kept below one. However, their acceleration of post-earthquake dissipation is a benefit in all cases. This may be made more optimal by allowing for the simple considerations presented herein.
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Lu, Chih-Wei. "Numerical Study of Soil-Pile Interaction during Earthquakes Considering Liquefaction." 京都大学 (Kyoto University), 2003. http://hdl.handle.net/2433/148518.
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Upadhyaya, Sneha. "Development of an Improved and Internally-Consistent Framework for Evaluating Liquefaction Damage Potential." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/95941.
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Soil liquefaction continues to be one of the leading causes of ground failure during earthquakes, resulting in significant damage to infrastructure around the world. The study presented herein aims to develop improved methodologies for predicting liquefaction triggering and the consequent damage potential such that the impacts of liquefaction on natural and built environment can be minimized. Towards this end, several research tasks are undertaken, with the primary focus being the development of a framework that consistently and sufficiently accounts for the mechanics of liquefaction triggering and surface manifestation. The four main contributions of this study include: (1) development of a framework for selecting an optimal factor of safety (FS) threshold for decision making based on project-specific costs of mispredicting liquefaction triggering, wherein the existing stress-based "simplified" model is used to predict liquefaction triggering; (2) rigorous investigation of manifestation severity index (MSI) thresholds for distinguishing cases with and without manifestation as a function of the average inferred soil-type within a soil profile, which may be employed to more accurately estimate liquefaction damage potential at sites having high fines-content, high plasticity soils; (3) development of a new manifestation model, termed Ishihara-inspired Liquefaction Severity Number (LSNish), that more fully accounts for the effects of non-liquefiable crust thickness and the effects of contractive/dilative tendencies of soil on the occurrence and severity of manifestation; and (4) development of a framework for deriving a "true" liquefaction triggering curve that is consistent with a defined manifestation model such that factors influential to triggering and manifestation are handled more rationally and consistently. While this study represents significant conceptual advance in how risk due to liquefaction is evaluated, additional work will be needed to further improve and validate the methodologies presented herein.Doctor of Philosophy
Soil liquefaction continues to be one of the leading causes of ground failure during earthquakes, resulting in significant damage to infrastructure around the world (e.g., the 2010-2011 Canterbury earthquake sequence in New Zealand, 2010 Maule earthquake in Chile, and the 2011 Tohoku earthquake in Japan). Soil liquefaction refers to a condition wherein saturated sandy soil loses strength as a result of earthquake shaking. Surface manifestations of liquefaction include features that are visible at the ground surface such as sand boils, ejecta, cracks, and settlement. The severity of manifestation is often used as a proxy for damage potential of liquefaction. The overarching objective of this dissertation is to develop improved models for predicting triggering (i.e., occurrence) and surface manifestation of liquefaction such that the impacts of liquefaction on the natural and built environment can be minimized. Towards this end, this dissertation makes the following main contributions: (1) development of an approach for selecting an appropriate factor of safety (FS) against liquefaction for decision making based on project-specific consequences, or costs of mispredicting liquefaction; (2) development of an approach that allows better interpretations of predictions of manifestation severity made by the existing models in profiles having high fines-content, high plasticity soil strata (e.g., clayey and silty soils), given that the models perform poorly in such conditions; (3) development of a new model for predicting the severity of manifestation that more fully accounts for factors controlling manifestation; and (4) development of a framework for predicting liquefaction triggering and surface manifestation such that the distinct factors influential to each phenomenon are handled more rationally and consistently.
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Green, Russell A. "Energy-Based Evaluation and Remediation of Liquefiable Soils." Diss., Virginia Tech, 2001. http://scholar.lib.vt.edu/theses/available/etd-08132001-170900.
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Luna, Ronaldo. "Liquefaction evaluation using a spatial analysis system." Diss., Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/19413.
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Reynolds, Frederick Douglas Misra Anil. "Seismic analysis of deep buried concrete water collection structure." Diss., UMK access, 2008.
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Thesis (Ph. D.)--School of Computing and Engineering and Dept. of Geosciences. University of Missouri--Kansas City, 2008."A dissertation in engineering and geosciences." Advisor: Anil Misra. Typescript. Vita. Title from "catalog record" of the print edition Description based on contents viewed Sept. 12, 2008. Includes bibliographical references (leaves 234-236). Online version of the print edition.
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GUILLEN, JORGE LUIS CARDENAS. "STUDY OF CONSTITUTIVE MODELS TO PREDICT SOIL LIQUEFACTION UNDER MONOTONIC LOADING." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2004. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=5729@1.
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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIORHistoricamente é sabido que muitas das rupturas ocorridas em barragens ou taludes naturais podem ser atribuídas ao fenômeno da liquefação de solos arenosos, causada pela ação de carregamentos dinâmicos gerados por explosão ou, mais freqüentemente, por terremotos. Quando liquefação ocorre, um súbito aumento da poropressão faz decrescer a resistência ao cisalhamento do solo e sua capacidade de suportar pontes e edifícios é significativamente reduzida. Solo liquefeito também pode exercer altas pressões sobre estruturas de contenção, causando inclinações da mesma e movimentos do solo que, por sua vez, originam recalques e destruição de estruturas localizadas sobre a superfície do terreno. O termo liquefação tem sido empregado para descrever fenômenos relacionados, que produzem efeitos similares, mas cujos mecanismos de formação são bastante diferentes. Estes fenômenos são modernamente descritos como fluxo por liquefação e mobilidade cíclica. Fluxo por liquefação é o fenômeno no qual o equilíbrio estático é destruído por carregamentos estáticos ou dinâmicos em um depósito de solo com baixa resistência residual. Colapsos causados por fluxo por liquefação são freqüentemente caracterizados por movimentos rápidos e de grande extensão. Mobilidade cíclica, por outro lado, é causada por carregamentos cíclicos em solos sob tensões cisalhantes estáticas inferiores à resistência ao cisalhamento do material, com as deformações desenvolvendo-se gradualmente. A execução de barragens de rejeito usando a técnica de construção à montante pode levar à ocorrência de liquefação estática se a velocidade de construção for suficientemente alta para causar o desenvolvimento de excessos de poropressão. A resposta de liquefação pode ser observada em amostras de solo fofo quando as tensões de cisalhamento atingem um pico seguido por uma fase de amolecimento aparente que, no caso de carregamento não drenado, é associado com a tendência do material em contrair de volume. Para alguns estados iniciais, a parte descendente da resposta do material pode ser seguida por uma fase crescente que se atenua à medida que o estado permanente ou crítico for atingido. Nesta dissertação, a modelagem da resposta de liquefação por carregamento estático, foi feita considerando-se modelos propostos na literatura por Juárez-Badillo (1999b) e Gutierrez e Verdugo (1995). Este último, principalmente após modificação introduzida pela dependência de alguns parâmetros em relação à tensão de confinamento, levou a resultados bastante satisfatórios nas retroanálises consideradas, apesar da relativa simplicidade da formulação.
Historically it is known that many failures in earth dams and natural slopes can be attributed to the phenomenon of sand liquefaction, caused by dynamic loads generated by earthquake shaking or other rapid loading, such as blasts. When liquefaction occurs, the strength of the soil decreases and its ability to support foundations for buildings and bridges is significantly reduced. Liquefied soil can also exerts higher pressure on retaining walls, which can cause them to tilt or slide, yielding settlement of the retained soil with risks of destruction of structures on the ground surface. The term liquefaction has actually been used to describe a number of related phenomena, which produce similar effects but whose mechanisms are quite different in nature. These phenomena can be divided into two main categories: flow liquefaction and cyclic mobility. Flow liquefaction is a phenomenon in which the static equilibrium is destroyed by static or dynamic loads in a soil deposit with low residual strength. Failures caused by flow liquefaction are often characterized by large and rapid movements. Cyclic mobility, on the other hand, is a liquefaction phenomenon triggered by cyclic loading, occurring in soil deposits with static shear stresses lower than the soil strength. Deformations due to cyclic mobility develop incrementally because of static and dynamic stresses that exist during an earthquake. The rising of tailing dams using the upstream construction technique can lead to static liquefaction failure if the rate of construction is sufficiently high to cause excess pore pressure to develop in the tailings. The liquefaction response is observed for loose specimens when the shear stress exhibits a peak followed by a phase of apparent softening that, in undrained loading, is associated with the tendency of the material to contract (densify). For some initial loading states, the descending part of the response is followed by an increasing part, leveling-off eventually when the material reaches the final, critical (steady) state. In this thesis, the modeling of the phenomenon of static liquefaction is carried out considering the constitutive models proposed in the literature by Juárez-Badillo (1999b) and Gutierrez & Verdugo (1995). The latter, mainly after introducing the assumption that some material parameters are stress dependent and not simple constants, as in the original version, produced good matching between experimental and predicted results, in spite the simplicity of the mathematical formulation.
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Copp, Darren Mark. "Partial saturation as a means of liquefaction mitigation in granular soil." Thesis, Swansea University, 2003. https://cronfa.swan.ac.uk/Record/cronfa42912.
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Liquefaction has been a widely-researched and controversial branch of geotechnical engineering after it first came to prominence during the Niigata/Alaskan earthquakes of 1964. Since then, engineers have developed various methods of liquefaction mitigation, in which soil improvement techniques are employed in order that the local development of those criteria which affect a soil's liquefaction susceptibility are inhibited. The most important of these criteria are rises in pore-water pressure, which reduce the capability of the soil to bear an effective stress, thereby compromising its engineering strength. If the excess pore-water pressure at a given point rises to a value which is numerically equal to the overburden stress at that point, then the effective stress will fall to zero, and the soil will behave as a viscous liquid, a condition which will have catastrophic consequences for both surface and sub-surface constructions. This thesis proposes the use of partially saturated soil as a means of liquefaction mitigation, as opposed to the more invasive methods which are currently advocated in the geotechnical engineering industry. Partial saturation increases the matric suction within a given soil. The matric suction, being a tensile stress, increases the strength of the soil, and reduces its ability to undergo shear strains. It is these shear strains which cause pore-water pressures to rise when a loosely bound, undrained soil mass is subjected to an earthquake loading. Newly-formulated methods of preparing loose, partially saturated sand specimens for triaxial testing are presented, as well as dynamic studies using a one-dimensional oscillator. The use of ProShake, a commercially-available software package, is also well documented, with special reference to change to the low-stiffness soil parameters caused by the introduction of partial saturation. Finally, the use of the author's own FORTRAN program, LSC, illustrates the concept of 'liquefaction sequencing', which is also presented here for the first time.
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Miyajima, Masakatsu. "Studies on Seismic Response of Buried Pipelines Induced by Soil Liquefaction." Kyoto University, 1990. http://hdl.handle.net/2433/138443.
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Horne, John C. "Effects of liquefaction-induced lateral spreading on pile foundations /." Thesis, Connect to this title online; UW restricted, 1996. http://hdl.handle.net/1773/10195.
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Spence, K. J. "Investigation of flowslides from the failure of mine tailings' dams." Thesis, University of Sheffield, 1992. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285652.
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Shibuya, Satoru. "Undrained behaviour of granular materials under principal stress rotation." Thesis, Imperial College London, 1985. http://hdl.handle.net/10044/1/7979.
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Luettich, Scott M. "Subsidence approach to risk of damage in earthquake-induced liquefaction." Thesis, Georgia Institute of Technology, 1987. http://hdl.handle.net/1853/20160.
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Latifi, Namin Manouchehr. "A multi-yield surface model in reference state soil mechanics for cohesionless soils and liquefaction problems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0004/NQ29060.pdf.
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Al, Bawwab Wa', and el Mohammad Kh. "Probabilistic Assessment Of Liquefaction-induced Lateral Ground Deformations." Phd thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/3/12606711/index.pdf.
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A new reliability-based probabilistic model is developed for the estimation of liquefaction-induced lateral ground spreading, taking into consideration the uncertainties within the model functional form and the descriptive variables as well. The new model is also introduced as performance-based probabilistic engineering tool.
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Schneider, James A. "Liquefaction response of soils in Mid-America evaluated by seismic cone tests." Thesis, Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/20147.
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Baska, David A. "An analytical/empirical model for prediction of lateral spread displacements /." Thesis, Connect to this title online; UW restricted, 2002. http://hdl.handle.net/1773/10182.
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Watts, Stephanie S. "Investigation and analysis of paleo-seismically induced lateral spreading mechanisms in Dixie Valley, Nevada /." abstract, 2008. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1456400.
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Thesis (M.S.)--University of Nevada, Reno, 2008."August, 2008." Includes bibliographical references (leaves 120-128). Library also has microfilm. Ann Arbor, Mich. : ProQuest Information and Learning Company, [2008]. 1 microfilm reel ; 35 mm. Online version available on the World Wide Web. Library also has electronic version on CD-ROM.
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Milstone, Barry Scott. "Effects of nonhomogeneous cementation in soils on resistance to earthquake effects." Thesis, Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/77896.
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Small amounts of cementation in a sand increase its ability to sustain static and dynamic loads, even in a liquefaction type environment. This has been shown in previous research examining the behavior of both naturally cemented and artificially prepared samples.
Cemented sands are present in many parts of the world and can be caused by either a variety of cementing agents or by cold welding at points of grain contact. They are generally quite difficult to sample, but artificially cemented sands have been shown to aptly model the behavior of natural materials, and allow for better test controls. Consequently, artificial samples were used exclusively for the present investigation which has three major objectives: to investigate the effects of a weakly cemented lens within a stronger mass; to determine how cementation affects the volume change characteristics of statically loaded samples; and, to describe the pore pressure generation of sands subjected to cyclic loading.
Prior to commencing the test program, a number of index tests were performed on the uncemented and cemented sand used during the laboratory investigation. It was revealed that cementation leads to increased void ratios which distort relative density calculations used to compare cemented and uncemented samples of similar dry unit weight. The practice of identifying samples by dry unit weight was adopted for this report.
Static triaxial compression tests were performed on 17 samples. Test results indicate that although the magnitude of volumetric strain at failure does not seem to be dictated by the level of cementation, there is a relationship with cementation and the rate of volume change at failure. A weak lens was seen to lower the static strength of the stronger mass. 26 stress controlled cyclic triaxial tests revealed that a weak lens lowers the liquefaction resistance of the stronger mass. The cyclic strength of the nonhomogeneous material, however, is higher than the independent strength of the weak lens. A weak lens has greater influence at relatively higher levels of cyclic stress. Pore pressure generation in cemented sands are seen to be controlled by strain. At shear strain levels below about 1%, cemented sands behave similarly to uncemented sands with pore pressures increasing more rapidly beyond that amount of strain. Consequently, pore pressure development during cyclic loading is described by a broken-back curve which is defined in the early stages by existing empirical relationships for uncemented sand. Pore pressure prediction may then be achieved using an equation for cemented sand, such as that developed in the present work.Master of Science
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Jessett, Clifford Alan. "Investigation of the liquefaction of a soil profile using in situ tests." Thesis, City University London, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316399.
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FAN, CHIH-CHUN, and 范致均. "A Comparison of Traditional Soil Liquefaction and Localization of Soil Liquefaction." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/4zj2z4.
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碩士逢甲大學
土木工程學系
106
Nowadays, it is often seen online that the phenomenon of soil liquefaction occurs in many countries located on seismic belts. Soil liquefaction occurs only locally in tectonic earthquakes. However, for a long time, researchers studying soil liquefaction have overlooked the fact that the main effect of tectonic earthquakes is localizations of deformations induced shear banding, while the secondary effect of such earthquakes is shear banding induced all around ground motion. As a result, the definition of soil liquefaction was based only on the secondary effects of tectonic earthquakes, and all alluvial plains in all counties and cities in Taiwan were evaluated as potential soil liquefaction areas. Soil liquefaction only occurs locally in the shear banding zones of each county/city, and the sum of the area of shear banding zones is less than 1% of the total area of each county/city. Therefore, the correct division of soil liquefaction zones can greatly simplify the disaster prevention and reduction projects for soil liquefaction, and the disaster reduction engineering based on the localizations of soil liquefactions can better achieve the desired goals. From this perspective, this thesis compares the definition of traditional soil liquefactions and localizations of soil liquefactions and various disaster reduction projects based on each definition in depth. Soil liquefaction occurs only locally in tectonic earthquakes, and is located in the shear banding zones with a high concentration of excess pore water pressure, rather than in all the alluvial soil layers subject to the all around ground motion. Therefore, according to the definition of localizations of soil liquefactions, it is possible to effectively distinguish between shear banding induced soil liquefaction and foundation’s punching shear failure, local shear failure, or general shear failure caused by ground motion, thus ensuring that the disaster reduction projects for buildings against soil liquefaction are more specific and clear. Keywords: localizations of soil liquefactions, traditional soil liquefaction, shear banding, ground motion.
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Kai, Huang Chun, and 黃群凱. "LIQUEFACTION POTENTIAL ANALYSIS FOR GRAVELLY SOIL." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/42487817866861023875.
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碩士國立中興大學
土木工程學系
89
ABSTRACT With frequent shocks in Taiwan, located at the Pacific earthquake belt, it is found that settlement and structural destruction are often induced by the soil liquefaction. From the past experiences, it is known that soil liquefaction generally occurs in saturated sand or silty fine sand. However, in the cases found in the areas of Wufeng, Nantou and Armenia, further studies need be conducted on the role that their gravelly solid liquefaction played in 1999. In reference to the boring data collected in 921 Chi - Chi earthquake, a site located at the Fu Tin Bridge in Wufeng was selected for the research. The in-situ physical tests in terms of density, grain size distribution and water content were conducted in the trench. Moreover, the remolded and large- scale soil samples (15 cm in diameter, 30 cm in height) were carried to perform the cyclic triaxial test in the laboratory. The discussion was then made on the relationships between the different relative density, the gravel content and the liquefaction resistance. The results were also compared with the one obtained from the large-scale cyclic triaxial test on the sand with different relative densities. The test results reveal that an increase in the gravel content or the relative density increases its liquefaction resistance strength, but decreases the axial strain. In addition, it is discovered that the liquefaction resistance of soil with gravel content in the range of 20% to 40% demonstrates the same strength as in pure sand with the relative density between 50% and 70%. Finally, a regression equation between the variation of parameters (gravel content and relative density) and the liquefaction resistance can be obtained for the gravelly liquefaction assessment.
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Ou, Li-ting, and 歐麗婷. "A Study of The Soil Liquefaction Probability." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/44283724503903906391.
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碩士長榮大學
土地管理與開發學系碩士班
91
Recently the earthquakes occurred in the world, that always brings soil liquefaction and the liquefaction areas were caused serious damages. Therefore the evaluation of soil liquefaction potential induced by earthquake became one of the most important research topics during the past few decades. Due to the uncertainty of earthquake parameters include earthquake magnitude, closest distance to the epicenter and earthquake duration, another the variability of soil parameters include soil of unit weight, depth and strength. Moreover the safety factor by transduction liquefaction potential analysis has uncertainties. Hence the rational evaluation methods of liquefaction were established in risk analysis concepts of probabilistic and statistical theory. This paper first uses the probabilistic seismic hazard analysis (PSHA) to evaluate earthquake magnitude and probability, in the site neighboring of fixed range and meantime. Then two methods of liquefaction probability had been developed, that including The method of statistical probability, that was developed from base of Youd and Idriss(1997) method, and considering the variability of parameters. Davies and Berrill(1982) seismic energy dissipation theory was adopted to develop a method of energy probability considering soil and ground conditions. In this research, the field data collected from Yuan-Lin area was used to perform the verification of the previously two evaluation methods of liquefaction probability. The results about two ways were similar because correlation of both annual liquefaction probabilities equals 0.92 that have very well responsibility. Furthermore, the observed ones in the liquefaction area of 921 earthquake had been compared with annual liquefaction probability contour. The effect In the neighborhood, the average annual probability of liquefaction by the developed methods, the area of most high liquefaction probability in Lun-Ya neighborhood, was similar to observed ones that soil liquefaction occurred in the 921 earthquake. The Lun-Ya neighborhood liquefaction average annual probability was approximately 0.0026 and the return period of liquefaction was approximately 385years. In the village, the high liquefaction average annual probability area was between south of No.148 county road and west of No.137 county road. The village was identified as high liquefaction area with a period of 300~500years and liquefaction average annual probability from 0.002~0.003. This paper adopted Ishihara(1993)’s method of liquefaction settlement to estimated settlement varied from 45~55cm, therefore have high liquefaction risk. It will be help for reference of the works of hazard mitigation planning. Keyword: liquefaction, probability, probabilistic seismic hazard analysis, seismic energy dissipation
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Daftari, Abbas. "New approach in prediction of soil liquefaction." Doctoral thesis, 2014. https://tubaf.qucosa.de/id/qucosa%3A23013.
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Liquefaction is the phenomena when there is loss of strength in saturated and cohesion-less soils because of increased pore water pressures and hence reduced effective stresses due to dynamic loading. It is a phenomenon in which the strength and stiffness of a soil is reduced by earthquake shaking or other rapid loading.
In this study, after the short review of liquefaction definition, the models of prediction and estimation of liquefaction were considered. Application of numerical modelling with two major software (FLAC & PLAXIS) for the Wildlife site liquefaction, under superstition earthquake in 1987 were compared and analysed.
Third step was started with introduction of Fuzzy logic and neural network as two common intelligent mathematical methods. These two patterns for prediction of soil liquefaction were combined. The “Neural network- Fuzzy logic-Liquefaction- Prediction” (NFLP) was applied for liquefaction prediction in Wildlife site. The results show the powerful prediction of liquefaction happening with high degree of accuracy in this case.
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Huang, Chi-Hao, and 黃啓豪. "Development of Probabilistic Soil Liquefaction Potential Maps." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/8e7rbg.
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碩士國立臺灣大學
土木工程學研究所
107
The primary contribution of this paper involves the development of a probabilistic soil liquefaction potential mapping in Taipei area using uncertainty analysis and combining several different methods, i.e. the Hyperbolic Function Method (HBF), the Artificial Neural Network (ANN) model, the Noise-assisted Multivariate Empirical Mode Decomposition (NAMEMD) algorithm, and the Perturbance Moment Method (PMM). The Hyperbolic Function Method (HBF) is employed to evaluate the soil liquefaction potential as its equations are simple, it is constructed using the Taiwan database and widely adopted by the government in Taiwan. Moreover, the Artificial Neural Network (ANN) model coupled with the Noise-assisted Multivariate Empirical Mode Decomposition (NAMEMD) algorithm is proposed for analyzing and forecasting the ground water level. First, based on the previous research work and experiments, the geotechnical data and earthquake data are transformed into random variables. Then, the proposed NAMEMD-ANN model is applied to the groundwater level data to investigate the characteristic time scales, and the forecasting time and the analysis length can be determined by the characteristic time scales. Furthermore, the Pertubances Moment Method (PMM) and Monte Carlo methods (MC) are used to assess the statistical moments and probability of output, the Liquefaction Potential Index (LPI). Finally, the probabilistic soil liquefaction potential mapping can be plotted by Kriging. The proposed modeling framework was applied to the Taipei Basin and the results which include the LPI mapping, the contour of exceedance probability, the percentage of areas with a high probability to liquefy in different period are demonstrated and discussed in this paper.
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Song, Chao-Min, and 宋朝敏. "Comparison of Prevention Methods of Soil Liquefaction." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/74730695507577247984.
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碩士國立中興大學
土木工程學系所
105
In 2016 the Taiwan Mino earthquake, resulting in Zeng Wenxi Rih-sin revetment , Jian-shan embankment serious damage, and caused the Tainan Wei-guan building collapsed, after the earthquake by experts and scholars to conduct by site inspection survey, the results show that the soil liquefaction caused by the disaster. At home and abroad, there are many structures or strata in the structure of the soil caused by soil liquefaction damage, such as the Japanese Hanshin earthquake caused serious damage to the structure of the river flood dike, more underground pipelines and other disasters occur. Therefore, countries are actively studying the control methods and construction methods of liquefaction of soils in relation to the structural load on the geological weak areas or the pipeline protection measures in the stratum. Soil liquefaction mainly occurs in the sandy soil area, the common characteristics are high in the formation of water content, due to external factors such as seismic force or other disturbed soil external force, can make the soil liquefaction phenomenon. In order to prevent the soil liquefaction or the soil after the occurrence of the improvement, the development of the improved method of up to several, the main improvement is to increase the soil stiffness, increase the site capacity and improve the soil shear wall and so on. In the improved way can be divided into increasing the density of the formation of soil strength, the formation of solidification and condensation, increase the excess pore water pressure disappearance, isolation or mitigation of soil deformation, reduce the groundwater level and other sites to improve the construction mode. This study is aimed at the more common control methods to carry out inventory analysis, to explore the advantages and disadvantages of different prevention and control of the characteristics of finishing, as a follow-up in the public works, private construction companies, design supervision and other advantages and disadvantages of reference, as a choice or design reference.
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HE, QI-CHENG, and 何啟誠. "The study of soil liquefaction potential evaluations." Thesis, 1992. http://ndltd.ncl.edu.tw/handle/85089547571873390068.
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Huang, Fu-Kuo, and 黃富國. "Analysis for Seismic Risk of Soil Liquefaction." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/68085724483665098008.
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Wu, Jiun-Yan, and 吳俊彥. "Evaluating soil liquefaction with artificial neural networks." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/77546578790367605585.
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Chang, Wen-jong. "Development of an in situ dynamic liquefaction test." Thesis, 2002. http://wwwlib.umi.com/cr/utexas/fullcit?p3099429.
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Jing-YuanHuang and 黃敬元. "Evaluation of Soil Liquefaction by Optimum Seeking Method." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/06295195432835025325.
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碩士國立成功大學
土木工程學系碩博士班
100
Soil liquefaction is always the one of the popular research topic related to numerous disasters induced from earthquake. Various methods used to assess the potential of the soil liquefaction have been developed in the past. In progress of evaluating potential of the soil liquefaction, major impact factors which affected different levels of soil liquefaction potential are set up. Case studies are usually conducted and the necessary soil strata properties are collected from field exploration and observed from laboratory experiment. The Principle Component Analysis Method was adopted in this study; firstly, various impact factors related to the potential of soil liquefaction which presented in the literatures were evaluated, then only several major impact factors were selected for the evaluation with quantifying. Both Golden Section Method and Fibonacci Seeking Method were adopted to analyze and check those data collected from the sites where soil liquefaction resulted from earthquakes which happened both in domestic and in abroad. In summary, a simple and effective model that integrates several other soil liquefaction potential models is developed in this study. Consequently, the model that developed in this study is able to judge the possibility of soil liquefaction in the soil stratum and the rate of successful evaluation is more than 80%. The model can be applied to the of geotechnical engineering practice.
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Lee, Ching-Yinn, and 李慶胤. "Application of Artificial Intelligence on Soil Liquefaction Assessmen." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/52084867233689933990.
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博士國立臺灣海洋大學
河海工程學系
100
Soil liquefaction is a vital topic of concern in the field of geotechnical engineering. Experts and scholars in this field seek methods to correctly determine whether liquefaction will occur at a site. The methods developed over the past several decades for evaluating soil liquefaction primarily involve simple empirical methods using in situ test data. Moreover, the current specifications and engineering practices adopted both domestically and internationally reference empirical formulae developed through these simple empirical methods. However, the great uncertainties inherent in earthquake mechanisms and soil properties complicate the selection of a suitable empirical formula for conducting regression analysis. Therefore, experts and scholars have attempted to discover an analytical method that is simpler, more reasonable, and better able to accurately determine soil liquefaction than traditional empirical formulae. With technological advances, artificial intelligence (AI) has become a popular topic in modern technological research and the development of computer applications technology. In a word, AI is an application of information technology that uses computing technology to simulate the thought processes of the human brain, thereby allowing a computer to conduct analyses and classification autonomously. Research into AI began in the 1950s and reached a peak at the end of the 1970s with the development of the Expert System. After this point, AI research met with certain obstacles and progressed slowly until the mid-1990s when several technological breakthroughs occurred. In particular, the invention of information processing methods such as machine learning and fuzzy logic incited widespread attention and excitement concerning AI. Artificial intelligence once again became a research topic of great interest in the international community. Among the branches of AI, machine learning receives the most attention. It currently demonstrates extensive applications, and has already been implemented successfully in word, voice, and image recognition systems. Applications of machine learning theory-for example, artificial neural networks (ANN) and support vector machines (SVM)—can simulate human thought and learning functions. These applications are advantageous for analytical processing of highly nonlinear relationships observed in geotechnical engineering domains such as soil liquefaction. Several scholars have confirmed that this technology is a powerful tool for handling liquefaction issues and is superior to traditional empirical assessment methods. Therefore, this study employs machine learning theory as a primary research tool to investigate the wider applications of current ANN and SVM methods. The study establishes a rapid and highly precise liquefaction evaluation model for Windows, which can serve as a reference for engineering design as well as disaster prevention and planning. The results of this study show that ANN and SVM surpass traditional simple empirical methods because of their accuracy in classifying liquefaction. Of the 2 methods, SVM is the most remarkable; it demonstrates a superior classification accuracy of 98.3%. SVM have proved to achieve good generalization performance and can be used as a practical tool for the prediction of soil liquefaction. Consequently, this study develops a Liquefaction Assessment program based on SVM (LA-SVM) that is constructed within a MATLAB/GUI (Graphical User Interface) Windows environment. This simple Windows-based LA-SVM provides an intuitive and user-friendly interface that obviates the use of graphs, formulae, or operating manuals. The user need only select items in Windows and enter training data and ranges to rapidly obtain classification results for forecast data and prediction accuracy. This LA-SVM program simplifies liquefaction assessment and achieves high accuracy rates, and should be promoted for further application.