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A retaining wall is subject to various limit states such as sliding, overturning and bearing capacity, and it can fail by anyone of them. Since a great deal of uncertainty is involved in the analysis of the limit states, the use of detenninistic conventional safety factors may produce a misleading result. The main objective of this study is to develop a procedure for the optimum design of a retaining wall by using the reliability theory. Typical gravity retaining walls with four different heights were selected in this study. The walls were designed first to satisfy the conventional design criteria, and later the safety indices inherent in the walls were computed by using Advanced First Order Second Moment method. With the safety indices the probabilities of failure for the three limit states were calculated and the probabilistically optimized design could be achieved by using the probability of failure. The influence of the coefficient of variation on the probability of failure was investigated. The ratios of base width to wall height which lead to the optimum design were obtained through a parametric study. / Ph. D.

ABSTRACT COMPARISON OF ANALYSIS METHODS OF EMBEDDED RETAINING WALLS HARMANDAR, Serkan M.S., Department of Civil Engineering Supervisor : Prof. Dr. Yener &Ouml / zkan Co -Supervisor : Dr. Oguz &Ccedil / aliSan December 2006, 123 pages In this study a single-propped embedded retaining wall supporting a cohesionless soil is investigated by four approaches, namely limit equilibrium, subgrade reaction, pseudo-finite element and finite element methods. Structural forces, such as strut loads, wall shear forces, bending moments are calculated by each method and results are compared. The analyses are carried for for three values of internal friction angle of soil / 30o, 35o, and 40o. Effects of modulus of soil elasticity of the backfill and wall stiffness on structural forces are investigated by using different values for these parameters. It is found that, in those of obtained by, limit equilibrium approach results in embedment depth greater than other methods. Minimum strut loads for the same soil and structure parameters are obtained by limit equilibrium method. An increase of Young&rsquo / s modulus of the soil results in decrease of the strut loads.

Baigiamajame magistro darbe analizuotos skirtingi liaunų atraminių sienų įrengimo variantai. Joms sumodeliuot ir paskaičiuot panaudota Prosheet ir GEO4 programos. Analizuojamos atraminės sienos, įrengtos smėliuose, kurių vidinės trinties kampas φ = 30 , sankabumas c = 0 kPa, ir moliuose, kurių vidinės trinties kampas φ = 26 , sankabumas c = 15 kPa. Skaičiavimų rezultatų lentelėse pateiktos įražų reikšmės ir skirtumai pavaizduoti grafiškai. Taip pat buvo išanalizuota, polių ilgiai, kuriuos suskaičiuoja kiekviena programa ir pavaizduota grafiškai. Išnagrinėjus, dėl ko gaunami skirtingi rezultatai, pateikiamos baigiamojo darbo išvados. Darbą sudaro 7 dalys: įvadas, 4 teorinės dalys, penktoji dalis - skaičiavimų rezultatai, išvados, literatūros sąrašas. Darbo apimtis – 63 p. teksto be priedų, 72 p. skaičiavimų rezultatų, 89 iliustr., 28 lent. Atskirai pridedami darbo priedai: 1 priedas 168 p. ir 2 priedas 168 p.. Priedai yra projektavimo programų atskirų variantų rezultatai, 3 priedas – paruoštas straipsnis vienuoliktai Lietuvos jaunųjų mokslininkų konferencijai bei pažyma apie straipsnio priėmimą spausdinimui. / In the master thesis it was analysed different method of retaining walls contruction. Prosheet and GEO4 programs werw used for calculation and design. Retaining walls were constructed in sandy soil or in clay. Properties of sand: angle of internal friction φ = 30 , cohesion c = 0 kPa. Properties of clayer soil: φ = 26 , c = 15 kPa. The stress values are given in the tables and differences showen graphically. Lengths of piles calculated are using each programme were analyzed and given graphically. After analysis of results, there were formulated an conclusion. Thesis consist of 7 chapters: introduction, 4 theoretical chapter, results of calculations, conclusions and references. Thesis consist of 63 text pages, 73 pages of calculations, including 89 illustrations and 28 tables. In addition 3 annexes are attached. Two of them are calculations and an article in the Young scientists conference.

Naudojamų hidrotechnikos statinių konstrukcijos veikiamos įvairių apkrovų ir neigiamo aplinkos poveikio nudėvimos, susiformuoja pažaidos. Pavojingiausios pažaidos, mažinančios pagrindinių laikančiųjų konstrukcijų (atraminių sienų) laikančiąją galią. Netekus laikomosios galios kyla grėsmė viso hidrotechnikos statinio patikimumui ir ilgaamžiškumui. Darbo tikslas – įvertinti hidromazgų atraminių sienų betono paviršinio sluoksnio ilgaamžiškumą apibrėžiančius rodiklius. Atlikus tyrimus nustatyta pagrindinė gelžbetoninių atraminių sienų charakteristika – betono gniuždomasis stipris. Pagal stiprio tyrimo rezultatus įvertintas Gailiušių hidromazgo atraminės sienos patikimumas ir nustatyta, kuris betono apsauginio sluoksnio ilgaamžiškumo rodiklis tiksliausiai atspindi atraminių sienų ilgaamžiškumo skaičiavimo rezultatus. Siūloma ilgaamžiškumo vertinimui naudoti 3.11 formulę. / Constructions of hydraulic structures are under the influence of different loads and negative environment impacts. Due to environmental impacts some deteriorations on the walls take place. The most dangerous kind of deteriorations reduces the bearing capacity of main constructions. The loss of the bearing capacity is very dangerous for the reliability and durability of the retaining wall. The purpose of this paper is to evaluate indicies defining the durability of the concrete covering layer of the retaining walls of hydroschemes. After the analysis it was found out the main characteristics of the reinforced concrete retaining walls – the compression strength of the concrete. The reliability of the retaining walls of Gailiušių hydroscheme was evaluated using the compression strength analysis. It was found out which indicator of the concrete covering layer durability gives the most correct counting results. It is suggested to use formula 3.11 for evaluation of durability.

Vertical inclusions of expanded polystyrene (EPS) placed behind rigid retaining walls were investigated as geofoam seismic buffers to reduce earthquake-induced loads. A numerical model was developed using the program FLAC and the model validated against 1-g shaking table test results of EPS geofoam seismic buffer models. Two constitutive models for the component materials were examined: elastic-perfectly plastic with Mohr-Coulomb (M-C) failure criterion and non-linear hysteresis damping model with equivalent linear method (ELM) approach. It was judged that the M-C model was sufficiently accurate for practical purposes. The mechanical property of interest to attenuate dynamic loads using a seismic buffer was the buffer stiffness defined as K = E/t (E = buffer elastic modulus, t = buffer thickness). For the range of parameters investigated in this study, K ≤ 50 MN/m3 was observed to be the practical range for the optimal design of these systems. Parametric numerical analyses were performed to generate design charts that can be used for the preliminary design of these systems. A new high capacity shaking table facility was constructed at RMC that can be used to study the seismic performance of earth structures. Reduced-scale models of geosynthetic reinforced soil (GRS) walls were built on this shaking table and then subjected to simulated earthquake loading conditions. In some shaking table tests, combined use of EPS geofoam and horizontal geosynthetic reinforcement layers was investigated. Numerical models were developed using program FLAC together with ELM and M-C constitutive models. Physical and numerical results were compared against predicted values using analysis methods found in the journal literature and in current North American design guidelines. The comparison shows that current Mononobe-Okabe (M-O) based analysis methods could not consistently satisfactorily predict measured reinforcement connection load distributions at all elevations under both static and dynamic loading conditions. The results from GRS model wall tests with combined EPS geofoam and geosynthetic reinforcement layers show that the inclusion of a EPS geofoam layer behind the GRS wall face can reduce earth loads acting on the wall facing to values well below those recorded for conventional GRS wall model configurations. / Thesis (Ph.D, Civil Engineering) -- Queen's University, 2011-04-28 16:56:57.084

Made available in DSpace on 2014-12-17T14:48:18Z (GMT). No. of bitstreams: 1 FabianaAS_DISSERT.pdf: 5525244 bytes, checksum: b567af14ad5856197ebf8368098dd7fb (MD5) Previous issue date: 2013-12-16 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / It is presented the analysis of a retaining wall designed for the basement of a residential building, located in Natal/RN, which consists in a spaced pile wall, anchored by tiebacks, in sand. This structure was instrumented in order to measure the wall s horizontal movements and the load distribution throughout the anchor fixed length. The horizontal movements were measured with an inclinometer, and the loads in the anchors were measured with strain gages, installed in three places throughout the anchor fixed length. Measurements for displacement were done right after the implementation of each stage of the building and right after the conclusion of the building, and the measurements for loads in the anchors were done during the performance test, at the moment of the locking off and, also, right after the conclusion of the building. From the data of displacement were obtained velocity and acceleration data of wall. It was found that the time elapsed on braced installation was decisive in the magnitude of the displacements. The maximum horizontal displacement of wall ranged between 0,18 and 0,66% of the final depth of excavation. The loads in the anchors strongly reduced to approximately half the anchor fixed length, followed an exponential distribution. Furthermore, it was found that there was a loss of load in the anchors over time, reaching 50% loss in one of them / O presente trabalho apresenta um estudo sobre uma estrutura de conten??o projetada para constru??o do subsolo de um edif?cio residencial multifamiliar, localizado na cidade de Natal/RN, que consiste em uma cortina de estacas escavadas ancorada por tirantes, em areia. Essa estrutura foi instrumentada a fim de se medirem os deslocamentos horizontais da cortina e a distribui??o de cargas ao longo do trecho ancorado dos tirantes. Os deslocamentos horizontais foram medidos atrav?s de inclin?metro, e as cargas nos tirantes foram obtidas com uso de extens?metros el?tricos de resist?ncia instalados em tr?s pontos ao longo do trecho ancorado. As medi??es de deslocamento foram feitas ap?s cada etapa de execu??o da cortina e ap?s a conclus?o da obra, enquanto as medi??es de carga nos tirantes foram feitas durante os ensaios de recebimento, no momento da incorpora??o e tamb?m ap?s a conclus?o da obra. A partir dos dados de deslocamento foram obtidos dados de velocidade e acelera??o da cortina. Constatou-se que o tempo gasto na instala??o do escoramento foi decisivo na magnitude dos deslocamentos. O deslocamento horizontal m?ximo final da cortina variou entre 0,18 e 0,66% da profundidade final de escava??o. As cargas nos tirantes sofrem uma redu??o muito acentuada at? aproximadamente a metade do trecho ancorado, seguindo uma distribui??o exponencial. Al?m disso, constatou-se que houve perda de carga nos tirantes ao longo do tempo, chegando a 50% de perda em um deles

El estudio consiste en un monitoreo de deformaciones con el uso de un inclinómetro instalado a trasdós de un muro de concreto armado con ocho niveles de anclajes en una excavación de 32 metros de profundidad en un proyecto de edificación en el distrito de San Isidro. Debido a que la metodología del muro anclado es muy utilizada en los últimos años en la ciudad de Lima, se considera necesario realizar un estudio del comportamiento de este tipo de estructura de retención, con el objetivo de conocer si la máxima deformación está dentro de los rangos permitidos por las normas internacionales, más aún en nuestro entorno, en donde no se tiene una normativa que regule este tipo de obras. La tesis se apoya en una revisión bibliográfica que ha permitido conocer estudios de deformaciones en estructuras de retención, analizar aspectos generales del comportamiento de los muros anclados, así como aspectos relacionados a la instrumentación geotécnica específicamente a los inclinómetros. La metodología adoptada seguirá un método cuantitativo, asimismo será de nivel descriptiva y también explicativa. Por otro lado, se considera que será de tipo aplicada siguiendo un diseño no experimental, además de ser prospectiva y transversal. Se ha logrado concluir que la deformación máxima del muro instrumentado está dentro de lo esperado, cumpliendo los rangos de las normas y de otras experiencias mencionadas en el marco teórico de esta tesis, además, tanto los resultados entregados por el inclinómetro como los presentados por el modelo en PLAXIS 2D, son similares, ya que muestra la tendencia hacia donde se dan las deformaciones. The study consists of a strain monitoring using an inclinometer installed to backfill of a retaining wall with eight anchors levels at a 32 meters deep excavation, in a building project in the district of San Isidro. The methodology of the retaining wall is widely used in recent years in the city of Lima, for that reason it is considered necessary to study the behavior of this type of retaining structure, in order to determine whether the maximum deformation is within the range allowed by international standards, even in our environment, where there is no legislation regulating this type of work. The thesis is based on a literature review, including studies of deformation of retaining structures, general aspects of the behavior of anchored walls and also issues related to geotechnical instrumentation specifically inclinometers. The methodology is based on a quantitative method, considering a descriptive level and an explanatory level as well. On the other hand, it is considered to be a rate applied contemplating a non-experimental design, as well as being prospective and transversal. The maximum deformation of the wall is within the expectations, satisfying the standards ranges and other experiences mentioned in the theoretical literature of this thesis and the results delivered by the inclinometer as the results presented by the PLAXIS 2D model are similar, because it shows the trend where the deformations are given.

The subject of this thesis is the reconstruction of the road III/29920 in the village Kuks and Stanovice, from the junction with the road I/37 to the bridge e.č. 29920-1, 1.5 km in length.

Dans le cadre du projet du Grand Paris Express, de nouvelles lignes de métro vont voir le jour afin d'accompagner la croissance du trafic et améliorer la performance du réseau de transport en Ile-de-France. Plusieurs gares de la nouvelle ligne 15 sud vont être excavées à des profondeurs importantes pouvant atteindre les 40m et soutenues par des parois moulées butonnées. Le recours à une modélisation aux éléments finis s'avère indispensable au vu du contexte exceptionnel du projet à savoir la maitrise de l'impact sur les avoisinants, la présence de formations peu perméables, surconsolidées et déformables (Argile Plastique) et la nécessité d'utiliser des modèles de sols avancés pour décrire le comportement du sol dans des plages de déformations caractéristiques des soutènements rigides.Ce travail de recherche vise à approfondir la compréhension du comportement des écrans de soutènement d’excavations profondes en analysant les limites des méthodes de modélisations à savoir la méthode des coefficients de réaction et la méthode des éléments finis et en confrontant leurs résultats avec des mesures fiables issues d’une excavation réelle. Une instrumentation avancée composée de fibre optique et de cellules de pressions a été mise en place dans la gare de Fort d’Issy-Vanves-Clamart et le retour d’expérience de cette dernière permet de statuer sur la pertinence des modélisations réalisées. / As part of the Grand Paris Express project, new subway lines will be created in order to support traffic growth and improve the performance of the transport network in the Ile-de-France region (France). Several stations of the new line 15 will be excavated at great depths up to 40m and supported by strutted retaining walls. The use of a finite element modeling is essential regarding the exceptional context of the project especially the impact on the surrounding structures, the presence of impervious soils, overconsolidated and deformable (Plastic Clay) and the need to use advanced constitutive models to describe the soils behavior in the typical strain ranges proper to rigid retaining walls.This research aims to deepen understanding of the behavior of retaining walls for deep excavations by analyzing the limitations of modelling namely finite element method and subgrade reaction method and by comparing their results with a real monitored excavation. An advanced monitoring based on fiber optic and pressure cells was set up in the station of Fort d’Issy-Vanves-Clamart and the measurements feedback allow assessing the relevance of the different adopted modellings.