Na prática brasileira, usualmente a previsão da capacidade de carga de fundações por estacas é baseada em métodos semi-empíricos, por meio de correlações diretas da resistência de ponta e por atrito lateral ao longo da estaca com os valores de NSPT. Entretanto, no caso de fundações por estacas helicoidais, ainda utilizam-se métodos teóricos que necessitam de valores de parâmetros geotécnicos obtidos indiretamente a partir de correlações com os valores de NSPT (coesão, peso específico, ângulo de atrito, coeficiente de empuxo). Portanto, nesta dissertação foi desenvolvido um método semi-empírico para estimar a capacidade de carga à tração de fundações por estacas helicoidais profundas por meio de correlações diretas com o valor de NSPT do solo de instalação da estaca. Além disso, são apresentados no presente trabalho valores de fator de torque KT, obtidos por análise estatística, para a verificação da capacidade de carga à tração da estaca usando-se medidas do torque necessário para instalá-la no terreno. Nesta pesquisa dois diferentes modelos para estimativa da capacidade de carga foram desenvolvidos e analisados estatisticamente. O estudo das características das amostras de fundações por estacas helicoidais usadas nesta pesquisa permitiu a subdivisão em grupos (tipo de solo e quantidade de hélices) de modo a se obter modelos mais precisos. Com os resultados deste trabalho, foi possível elaborar recomendações para projeto e execução de estacas helicoidais, bem como desenvolver um modelo para estimar a capacidade de carga à tração de estacas helicoidais instaladas em solos similares aos das estacas usadas neste estudo. / The pile capacity in Brazil is usually predicted by semi-empirical methods based on direct correlations between SPT-N values and pile shaft and pile base resistance. However, the uplift capacity of helical piles is still calculated using theoretical methods based on soil parameters, as: cohesion, unit weight, friction angle, and lateral earth pressure coefficient. In this case, these parameters are obtained indirectly from correlations with values of SPT-N. This dissertation was inspired by the need of a more appropriate method to calculate the uplift capacity of helical piles, by correlating the capacity of the bearing plates directly with the soil type and SPT-N values. In this work, it was developed a semi-empirical method for estimating the pullout capacity of deep helical piles by using SPT test results, similarly to the other methods used for conventional piles. Also, this work presents some results of torque factor, obtained by statistical analysis, to the verification of the pile capacity by using the torque recorded at the end of pile installation. In this research, it was performed several statistical analysis to obtain appropriate models to estimate the uplift capacity of helical piles. The cases of helical piles used in this investigation are classified into groups according to the soil type and the number of helices. As a result, detailed evaluations and recommendations for improvement of helical pile design are presented. The proposed model is recommended to calculate the uplift capacity of helical piles installed in similar soils to that used in this study.

Resumo: A evolução do Arco de Ponta Grossa, na região sudeste brasileira, durante o Meso-Cenozóico, apresenta uma estreita relação com os eventos tectono-magmáticos responsáveis pela abertura do Oceano Atlântico- Sul. A utilização do Método de Datação por Traços de Fissão em apatitas, nessa região, permitiu a identificação de cinco eventos térmicos, responsáveis pela estruturação dessa feição, a partir do Cretáceo. São eles: Evento A - Aquecimento em 130 Ma, relacionado ao evento de ruptura do Gondwana Sul-Ocidental e geração do Oceano Atlântico-Sul; Evento B - Resfriamento em 110 Ma, associado à reativação de antigas zonas de cisalhamento e/ou falhas geradas na ocasião do evento de ruptura do Gondwana Sul-Ocidental; Evento C - Aquecimento em 90 Ma, associado à um soerguimento regional, interpretado como alçamento de isógradas, provavelmente como reflexo do soerguimento do Arco de Ponta Grossa e conseqüente sedimentação correlativa (Grupo Bauru ls, no interior continental, e seqüência inferior da Formação Santos, na Bacia homônima), bem como de intrusões alcalinas; Evento D - Resfriamento em 60 Ma, correlacionado à um evento erosivo, que propiciou a formação de uma extensa superfície de erosão, neste caso a Superfície Sulamericana, amplamente registrada tanto na parte continental como na porção submersa adjacente ao Arco de Ponta Grossa (sob a forma de discordância regional na Bacia de Santos); Evento E - Resfriamento em 30/20 Ma, associado à atuação de ciclos erosivos, instalação de bacias tafrogênicas e, localmente, intrusões alcalinas. / Abstract: The evolution of Ponta Grossa Arch, in southeastern Brazil, during Mesozoic-Cenozoic, seems to be related to the tectono-thermal events related to South Atlantic opening. The use of Apatite fission Track Method, in this region, allowed the recognition of five thermal events, responsible for the formation of this feature, since Cretaceous, which are: Event A - Heating event in 130 Ma, related to the Southeastern Gondwana break-up and the origin of South Atlantic Ocean; Event B - Cooling event in 110 Ma, associated to the shear zones reactivation and/or faults generated during Gondwana break-up; Event C - Heating event in 90 Ma, associated with a regional uplift, interpreted as uplift isotherms, probably as a reflection of Ponta Grossa Arch uplift and correlated sedimentation (Bauru Group ls, in continent and the inferior sequence of Santos Formation, in Santos Basin), and alkaline intrusions; Event D - Cooling event in 60 Ma, correspondent to an erosional event, that formed an extended erosional surface, in this case, Sulamericana Surface, registered both in continental region and in offshore portion (registered as a regional discordance in Santos Basin); Event E - Cooling in 30/20 Ma, related to erosional cycles, tafrogenic basins origin and, locally, alkaline intrusions. / Orientador: Peter Christian Hackspacher / Coorientador: Antonio Roberto Saad / Banca: Julio Cesar Hadler Neto / Banca: Delzio de Lima Machado Junior / Mestre

As estacas helicoidais têm sido empregadas em diversos tipos de obras no Brasil e no mundo, principalmente em casos em que a fundação é submetida a carregamentos simultâneos de tração e de compressão ou que necessitam de rápida e facilitada instalação. O maior uso nacional é em fundações de torres de linhas de transmissão de energia, no entanto, são escassos os estudos do comportamento deste tipo de estaca em solos tropicais brasileiros. Considerando-se o crescimento do uso de estacas helicoidais no Brasil, e a necessidade de um melhor entendimento do comportamento deste tipo de fundação em nossos solos, o presente trabalho foi realizado para verificar a influência do arranjo das hélices, tanto do diâmetro quanto da quantidade, na capacidade de carga à tração das estacas helicoidais multi-hélices, instaladas em solo tropical da região de São Carlos, na cidade de Itirapina próxima a lagoa do Broa. A campanha de investigações geotécnicas foi composta por sondagens de simples reconhecimento (SPT) e ensaios de cone (CPT). Foram ensaiadas nove estacas, com diferentes configurações de diâmetro e de número de hélices, instaladas com a ponta em mesma profundidade, mesmo espaçamento entre hélices (igual a três vezes o maior diâmetro) e mesmo diâmetro de haste. Nesta investigação foram medidos os torques de instalação, e realizadas provas de cargas à tração do tipo estática com carregamento rápido. Como conclusões, o atrito lateral obtido com o ensaio CPT foi útil para verificar o efeito de perda de resistência do solo com a instalação da estaca; o método de capacidades de carga individuais obteve estimativas mais próximas as medidas em prova de carga; o efeito da configuração (cônicas ou cilíndricas) influencia no torque de instalação, mas não na capacidade de carga das estacas; o acréscimo de diâmetro médio das estacas é interessante para acréscimos na capacidade de carga, no entanto o acréscimo do número de hélices, a hélice superior sempre absorve menores cargas do que a hélice da ponta da estaca. / The helical piles have been used in different types of constructions, especially in cases where the foundation is subjected to tension and compression loads. In Brazil, this type of pile is normally used as the foundation of towers of power transmission lines, as guyed masts and self-supporting towers. However, there are few studies about the behavior of helical piles in Brazilian tropical soils. Considering the growing use of helical piles in Brazil, and the need of a better understanding of the behavior of this type of foundation in our soils, this study was conducted to evaluate the influence of the arrangement of the helices on the uplift capacity of helical piles installed in the tropical soil of São Carlos zone of São Paulo State. For this study, geotechnical investigations were carried out: standard penetration tests (SPT) and cone tests (CPT). Nine piles with different configurations (diameter and number of blades) were tested after being installed with the tip at the same final depth into the ground, and the same relative helix spacing (S/D>3). For this investigation, the torque necessary to install the piles were recorded, and subsequently static tensile loads tests were performed on all piles. As results: the lateral friction obtained with the CPT test was useful to check the effect of losing soil strength with the installation of the screw pile, the individual bearing method obtained estimates closer measurements in load test then cylindrical shear method; the effect of configuration (conical or cylindrical) influences on the torque installation, but not the uplift capacity of the screw piles, increases in the size of average diameter of helix in screw piles make increases in uplift capacity, however the increase in the number of helix did not appear as good as increases in the average diameter of the helix.

Orientador: David de Carvalho / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola / Made available in DSpace on 2018-08-12T07:40:33Z (GMT). No. of bitstreams: 1 PaschoalinFilho_JoaoAlexandre_D.pdf: 6669180 bytes, checksum: 78d0e0cf2f6cfc3054d3c7bdf89b2116 (MD5) Previous issue date: 2008 / Resumo: Apresenta-se neste trabalho o estudo do comportamento de diferentes tipos de estacas, implantadas em solo de diabásio, quando submetidas a esforços de tração, através da realização de provas de carga estática do tipo lenta. Foram executadas quatro estacas tipo raiz sendo uma de 23m de comprimento e 310 mm de diâmetro e três instrumentadas de 12m de comprimento com 410 mm de diâmetro; três estacas metálicas perfil I tipo W250x32,7, sendo uma com 12m e duas com 18m de comprimento; duas estacas tipo trilho TR37 sendo uma com 18m e outra de 20,5m de comprimento. Foram também estudadas as seguintes estacas já anteriormente instaladas no local em estudo: três estacas escavadas (sem lama bentonítica) de 12m de comprimento e 400 mm de diâmetro, três estacas tipo hélice contínua com 12m de comprimento e 400 mm de diâmetro, uma estaca tipo ômega de 12m de comprimento e 370 mm de diâmetro e uma estaca prémoldada de oncreto com 14m de comprimento e 180 mm de diâmetro. O local de execução das estacas foi o Campo Experimental para Estudos em Mecânica dos Solos e Fundações localizado dentro dos limites da Faculdade de Engenharia Agrícola da Unicamp (Universidade Estadual de Campinas), localizada no município de Campinas, interior de São Paulo. O subsolo do local é constituído por solo poroso de diabásio, cuja primeira camada de 6,5m de espessura é constituída de argila silto-arenosa, seguida de uma camada de silte arenoso e nível de água a 17m de profundidade. Foram utilizados os seguintes métodos para a estimativa da capacidade de carga próprios para esforços de tração como: Método do Tronco de Cone, Método do Cilindro de Atrito, Método de Meyerhoff (1973); Método de Kulhawy (1985); Método de Levacher & Sieffert (1984) e Método da Universidade de Grenoble de acordo com Martin (1963). Os valores de capacidade de carga estimados por meio de cada método foram então confrontados com os valores de carga máxima obtidos por meio das provas de carga. As resistências laterais totais de cada estaca foram determinadas por meio dos seguintes métodos semi-empíricos próprios para esforços de compressão: Décourt & Quaresma (1998); Décourt & Quaresma (1978); Aoki & Velloso (1975 - SPT); Aoki & Velloso (1975 - CPT); David Cabral (1986); P.P Velloso (1981); Teixeira (1996); Antunes & Cabral (1996); FUNDESP (1998) e Monteiro (2000). Os valores de resistência lateral obtidos pelos métodos foram comparados aos valores de carga máxima obtidos pelas provas de carga. As capacidades de carga a tração das estacas estudadas foram previstas por meio dos seguintes métodos próprios para extrapolação de curvas carga x recalque: Van der Veen (1953), Décourt (1996), NBR 6122/96 e Davisson (1978). Para os métodos de Van der Veen (1953) e Décourt (1996) foram estimadas cargas máximas a partir de pontos da curva carga x recalque situados até recalques referentes a cargas de 50, 60, 70, 80 e 90% das cargas máximas atingidas pelas provas. Este procedimento teve como objetivo verificar a aplicabilidade destes métodos caso as provas de carga fossem prematuramente interrompidas. Foram também previstos valores de recalques obtidos para cargas referentes a PC/2 por meio dos métodos de Vesic (1969, 1975a) e Poulos & Davis (1980). Foram também determinadas nesta pesquisa correlações matemáticas entre valores de atrito lateral médios para cada estaca estudada (rl), determinados por meio das provas de carga, e dados de resistência lateral obtidos utilizando-se parâmetros provenientes de ensaios de cone (CPT) e SPT-T, como fs (para CPT) e fTmáximo e fTmínimo (para SPT-T). / Abstract: This research presents the behavior of different kinds of piles conducted in unsaturated diabasic porous soil submitted to uplift forces. For this research there were built the follow piles: three instrumented root piles with 12m length and 410mm of nominal diameter, one root pile with nominal diameter of 310mm and 23m length, two metallic piles type W250x32.7 with 18 meters length, one metallic pile with 12m length and type W250x32.7, two trail piles TR37 type, one of them with 18 meters length and the other with 20.5 meters length. There were also considered in this research the follow piles already conducted at the studied area: three bored piles with 12 meters length and diameter of 400mm, three Continuous Flight Auger piles with 12 meters length and diameter of 400mm, one Omega pile with 12m length and diameter of 370mm and one Concrete Precast pile with 14 meter length and diameter of 180mm. The piles were built at the site for Experimental Studies in Soil Mechanics and Foundations. This experimental area is situated at the State University of Campinas, in the interior region of the state of São Paulo, Brazil. The local subsoil is basically composed by a superficial layer of approximately 6,5m thick composed of high porosity silt-sand clay followed by clayey-sandy silt. The water table is not checked until a depth of 17 meters. The carrying capacity of the studied piles was also provided by means of theoretical methods appropriate for uplift forces. The methods considered were: Method of the Trunk of Cone, Method of Cylinder of Friction, Meyerhoff (1973), Kulhawy (1985), Levacher & Sieffert (1984) and University of Grenoble in according to Martin (1963). The values estimated using the methods under consideration were compared to those obtained by means of the load tests. Methods for "load x settlement" curves extrapolation such as: Van der Veen (1953), Décourt (1998) and NBR 6.122 (1996) and Davisson (1973) were also used to provide the carrying capacity of the studied piles. There were also provided by Van der Veen (1953) and Décourt the ultimate loads for each using 50, 60, 70, 80 e 90% of the ultimate load obtained by means of the load tests. Semi-empirical methods, appropriate for compression forces, were also used considering only the portion of lateral resistance. The methods studied were the following: Décourt & Quaresma (1998); Décourt & Quaresma (1978); Aoki & Veloso (1975 - SPT); Aoki & Veloso (1975 - CPT); David Cabral (1986); P.P Velloso (1981); Teixeira (1996); Antunes & Cabral (1996); FUNDESP (1998) e Monteiro (2000). The obtained values of lateral resistance were compared to the maximum load obtained by means of the load tests. The settlements of the studied piles were also determinate by Vesic (1969, 1975a) and Poulos & Davis (1980). Mathematical correlations between lateral friction values, obtained by means of the load tests, and lateral resistance values obtained by means of field tests like SPT-T and CPT were also provided in this research. / Doutorado / Construções Rurais e Ambiencia / Doutor em Engenharia Agrícola

The development of the construction industry brought the new methods of structural design, which have been introduced to engineers, although overall this phenomenon has increased building costs. A cost-effective construction is one of the major decision points during the definition of any engineering project, therefore, due to the opposing concepts of these two statements, revising design standards and codes are essential in order to provide adequate and cost-effective design requirements. A single-ply roof system is a relatively new method of roof construction that has been used in the building industry in recent decades, which seems to have undergone dramatic changes due to significant structural failures that have occurred through the years. Wind-induced damage on flat roofs is a common problem for low-rise buildings and much of this damage is initiated when the steel deck roof fails, leading to the overall roofing system collapse. The FM (Factory Mutual) design recommendations, which is a standard that recommends allowable dimensions and wind rating for the roofing products, have provided tabulated steel deck span dimensions and fasteners distance for many years. To update the FM design recommendations extensive experimental and analytical investigations are required. In the current study an experimental program was conducted at the National Research Council of Canada (NRC) on flat roofing systems, for simulating the wind uplift effect on several roofing systems samples, as recommended by FM design recommendations. A Finite Element Model (FEM) of the same roofing systems as those used in the experimental cases was developed and different loading patterns were analysed for providing a better simulation of the deflection, moments and forces responses, as measured during the experiments. The FEM was validated with the experimental results and was further employed for applying the FE analysis for more steel deck span dimensions and wind rating cases, as provided in the FM design recommendations tables. These results were reported to the Single Ply Roof Industry (SPRI) Committee where the updating of the FM design tables is currently under discussion.

Die Grundwasserstände unterliegen in den Gebieten des Braunkohlenbergbaus permanenter, bergbaulich bedingter Veränderung. Im Einflussbereich der aktiven Braunkohlentagebaue überwiegen sinkende - im Bereich der ehemaligen Tagebaubereiche nach Einstellung der Wasserhaltungsmaßnahmen dagegen steigende Grundwasserstände. Der Grundwasserwiederanstieg im Verantwortungsbereich der LMBV mbH ist schon weit vorangeschritten aber noch nicht überall abgeschlossen. Im Zuge der Auswertung von regelmäßig durchgeführten Präzisionsnivellements wurden in den gewachsenen Randbereichen der in Flutung befindlichen Tagebauseen Hebungen festgestellt, die in ihrer räumlichen Ausdehnung und dem Betrag mit den Ergebnissen der Beobachtungen der Grundwasserstände korrelieren. Rückblickend werden die Zusammenhänge zwischen Grundwasserwiederanstieg und Hebungen des gewachsenen Bodens anhand von Beispielen von bereits gefluteten Tagebauseen aus dem Mitteldeutschen Braunkohlenrevier betrachtet. Die festgestellten Hebungen vollziehen sich längerfristig über mehrere Jahre. Die Hebungsbeträge erreichen maximale Werte von einigen Zentimetern - erreichen aber nicht die Beträge der früheren sümpfungsbedingten Senkungen. Schädliche Auswirkungen auf Bauwerke durch grundwasserwiederanstiegsbedingte Hebungen waren nicht zu erwarten und sind auch nicht eingetreten. / Water tables in lignite mining areas are characterized by a permanent mining-related variation. In the sphere of influence of the active lignite mines preponderates decreasing – in reach of the abandoned lignite mining areas in contrast increasing water tables. The groundwater resurgence within the areas of responsibility of LMBV mbH is widely pro-ceeded but yet not completed in all areas. In the course of the evaluation of regularly conducted precision levellings uplifts were detected in the natural boundary areas of post-mining lakes still in flooding progress. These uplifts correlate in their regional/areal dimension and magnitude with the results of the water tables. The coherence between groundwater resurgence and the uplifts will be examined retrospectively based on examples of flooded post-mining lakes from the mining area around the cities of Leipzig and Halle. The observed elevation take place over some years. The elevation amount reaches maximum values of a few centimeters, but doesn’t reach the amount of the former drainage caused subsidence. Adverse effects on buildings by groundwater resurgence caused elevation were not expected and didn’t occur so far.

Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第15340号 / 工博第3219号 / 新制||工||1485(附属図書館) / 27818 / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 井合 進, 教授 岡 二三生, 教授 木村 亮 / 学位規則第4条第1項該当

Abstract The study focused on geological and ecological development of ten lacustrine basins in the Hailuoto – Oulunsalo – Lumijoki siltstone and claystone area of Muhos, and two lacustrine basins in the Kuivaniemi – Simo area of Svecokarelian schists and gneisses. The study on water quality, soil and sediment geochemistry, and sediment diatom assemblages of natural lacustrine basins, provide background values, which can be used in assessing the state of the water body in environmental studies. Water quality of the ten water bodies was monitored for 14 years. Water samples were studied for 28 different parameters. Soil and sediment geochemistry was studied on seven lacustrine basins by three different extraction methods. Extracts were analysed for ten parameters. The sediment diatom species were examined from five water bodies in accuracy of 1 cm thick layers. In the study area new water bodies are forming mainly in two different ways: isolation of marine bights and damming of dune ponds. The water bodies could be classified into five different groups based on water quality, sediment geochemistry, and sediment diatom assemblages. These also represent the different developmental stages of the lacustrine basins of the land uplift coast. Parameters of the water quality data could be divided into two main groups: electrolyte group and nutrient group. The water bodies studied segregated into two main categories: coastal and inland water bodies. The concentrations of electrolytes and nutrients were characteristically higher in the coastal water bodies compared to the inland water bodies. During the monitoring period eutrophication of the water bodies and significant seasonal variations of water quality were observed. According to the water quality data and diatom indices the prevailing conditions in the coastal water bodies were eutrophic; and in the inland water bodies ranging from mesotrophic to oligotrophic. The lacustrine basins were grouped mainly in accordance with their geochemical provinces. The geochemical gradients of soil, water quality and sediment in the chronosequence of the catchments on Hailuoto Island showed that when marine influence decreased, the lacustrine basins of the land uplift coast were observed to be oligotrophying, acidifying, and terrestrializating naturally. / Tiivistelmä Tutkimus keskittyi kymmenen Hailuodon, Oulunsalon, ja Lumijoen Muhos-muodostuman hiekka- ja savikivialueen järvialtaan sekä kahden Iin ja Simon svekokarelisen liuske- ja gneissialueen järvialtaan geologisen ja ekologisen kehityksen selvittämiseen. Luonnonmukaisesti kehittyneen järviallassarjan veden laadun, maaperän ja sedimentin geokemian sekä sedimentin piileväkoostumuksen tutkimus tarjoaa tausta-arvoja, joita voidaan hyödyntää arvioitaessa vesialueen tilaa ympäristötutkimuksissa. Kymmenen vesialtaan veden laatua seurattiin 14 vuoden ajan. Vesinäytteistä analysoitiin 28 eri parametria. Seitsemän järvialtaan valuma-alueen maaperän ja sedimentin geokemiaa tutkittiin käyttäen kolmea erilaista uutosmenetelmää. Uutoksista analysoitiin 10 parametria. Viiden vesialtaan sedimentin piilevälajisto tutkittiin 1 cm:n kerrostarkkuudella. Tutkimusalueella uusia vesialtaita muodostuu pääasiassa kahdella tavalla: merenlahdekkeiden kuroutumisen ja dyynilampien patoutumisen seurauksena. Vesialtaat voitiin luokitella veden laadun, sedimentin geokemian ja piilevälajiston perusteella viiteen eri ryhmään, jotka edustivat myös maankohoamisrannikon järvialtaiden eri kehitystasoja. Vedenlaatuaineiston parametrit voitiin jakaa kahteen pääryhmään: elektrolyyttiryhmä ja ravinneryhmä. Tutkittavat altaat erottuivat kahteen pääluokkaan: ranta-altaat ja sisämaan altaat. Tunnusomaista ranta-altaille verrattuna sisämaan altaisiin oli korkeammat elektrolyyttien ja ravinteiden pitoisuudet. Seurantajaksolla havaittiin ranta-altaiden luontaista rehevöitymistä sekä merkitseviä veden laadun vuodenaikakohtaisia vaihteluita. Vedenlaatuaineiston ja piileväindeksien mukaan vallitsevat olosuhteet rannan vesialtaissa olivat eutrofiset ja sisämaan vesialtaissa mesotrofisista oligotrofisiin. Järvialtaat ryhmittyivät lähinnä geokemiallisten provinssiensa mukaisesti. Hailuodon valuma-alueiden maaperän, veden laadun ja sedimentin geokemialliset gradientit osoittivat, että merellisen vaikutuksen vähetessä maankohoamisrannikon järvialtaat luontaisesti karuuntuvat, happamoituvat ja soistuvat.

La chaîne du Rif (Nord du Maroc) constitue, avec les Cordillères des Bétiques (Sud de l’Espagne), la terminaison occidentale de la ceinture alpine. C’est un secteur clé pour la compréhension des mouvements verticaux associés aux processus orogéniques. Jusqu’à présent, aucune étude n’a permis de contraindre les mouvements verticaux postérieurs au Miocène inférieur, malgré la présence de dépôts marins pliocènes surélevés. L’objectif de ce travail est d’apporter des arguments permettant de discuter des mécanismes géochronologiques et cinématiques impliqués dans les mouvements verticaux de la marge du Rif depuis le Néogène. Une comparaison des déplacements identifiés dans les zones internes, a pu être effectuée, avec ceux estimés dans le domaine des flyschs (Sud de l’accident de Jebha), grâce aux données AHe. Les corrélations entre mouvements verticaux et évolution du champ de déformation mettent en évidence le lien existant entre les périodes de mouvements verticaux majeurs et les phases d’extension radiale. 1-Les derniers stades d’exhumation des unités métamorphiques, depuis près de 12-10 km de profondeur, résultent d’un stade d’extension radiale affectant ces formations. Le domaine de collapse s’étend depuis le faciès Schiste Vert jusqu’au domaine fragile durant l’Aquitano-Burdigalien. Les mouvements extensifs sont limités aux parties superficielles de l’orogène tandis que les parties plus profondes et situées en avant-chaîne sont en compression. 2-Une période de surrection lente associée à de l’extension radiale, affecte l’intégralité des zones internes, au moins depuis le Pliocène inférieur. La zone des flyschs se surélève à plus grande vitesse. / The Rif chain (Northern Morocco) belongs, with the Betic Cordillera (Southern Spain), to the westernmost part of the Alpine belt. This sector is one of the main targets for the comprehension of vertical movements linked to orogenic processes. Despite the numerous investigations lead on the Pliocene uplifted deposits in the Rif Chain, the timing and amplitude of the vertical motions subsequent to the period of cooling have never been constrained. This work aims to discuss the geodynamical processes involved in the vertical motion of the Rif margin since the Neogene. A comparison between the vertical movements determined in the internal zones and estimated in the flyschs domain (South of Jebha fault), has been realized on the basis of AHe data. Correlations reported between the vertical movements and the evolution of the stress field highlighted the linkage between the main stages of vertical motion and extension period with a radial pattern. 1-The latest exhumation stages of the deep-seated metamorphic rocks, from 12-10 km of depth, were triggered by the radial extension of these units. The collapse extended from the low grade metamorphism (Greenschists facies) to the brittle strata during the Aquitano-Burdigalian times. This extension is expressed in the superficial units, whereas deepest parts and sectors at the front of the Rif chain underwent a compression. 2-A second uplift stage proceeds at a very slow raising pace and is associated to radial extension in throughout the internal zones since the Lower Pliocene. Le flyschs sector was uplifted faster since the Late Miocene.

Three-dimensional mechanical simulations of the San Andreas fault (SAF) within the Coachella Valley in California produce deformation that match geologic observations and demonstrate the impact of fault geometry on uplift patterns. Most models that include the Coachella Valley segment of the SAF have assumed a vertical orientation, but recent studies suggest that this segment dips 60-70° northeast. We compare models with varied fault geometry and evaluate how well they reproduce observed uplift patterns. Our model with a dipping SAF matches geologic observations, while models containing a vertical fault do not. This suggests that the active Coachella Valley segment of the SAF dips 60-70° northeast. Since ~1.5 Ma, the SAF in this region has undergone a major reorganization that entailed initiation of the San Jacinto fault and termination of slip on the West Salton detachment fault. The trace of the SAF itself has also evolved, with several shifts in activity through the San Gorgonio Pass. Despite a rich geologic record of these changes, the mechanisms that controlled abandonment of faults, initiation of new strands, and shifting loci of uplift are poorly understood. We model snapshots in time through the evolution of the fault system, and assess the mechanical viability of our snapshots by comparison with uplift patterns inferred from the stratigraphic record. Model results are compared with vertical axis rotation. We examine incipient faulting using maps of strain energy density, and explore changes to the mechanical efficiency of the system to better understand the evolution of this fault system.