The Experts below are selected from a list of 15 Experts worldwide ranked by ideXlab platform
Wotring, Donald Craig - One of the best experts on this subject based on the ideXlab platform.
-
Visualization in Geomechanics With an Application to Deep Excavations
1Co-Authors: Wotring, Donald CraigAbstract:331 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2004.The second part of this dissertation explores the behavior of deep Excavation numerical analyses, with the aid of the visualization techniques presented herein. First, a 2D plane strain Excavation analysis is explored. Second, a 3D linear Excavation is modeled using a variety of Excavation techniques. Finally, a 3D Excavation with a square footprint is modeled. Advanced visualization techniques are used to understand the complex 3D soil behavior that results. The visualization techniques present a vivid picture of the effect of Excavation Method selection on soil behavior and the development of a 3D arch for a square Excavation.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD
Hell Markus - One of the best experts on this subject based on the ideXlab platform.
-
Tiefe Baugruben
2019Co-Authors: Hell MarkusAbstract:Bei Bauarbeiten unterhalb der Geländeoberkante ist vorab eine Baugrube auszuheben. Mit wachsender Tiefe der Aushubsohle nimmt die Herstellung einer Baugrube eine wesentliche Rolle ein. Hierfür ist ein geeignetes Bauverfahren in der Planungsphase auszuwählen. Dabei ist vorab zu klären, welche Einflüsse bei einer tiefen Baugrube zu berücksichtigen sind. Die vorliegende Diplomarbeit beleuchtet zu Beginn auf Grundlage einer Literaturrecherche und auf Basis von Fachplanergesprächen relevante Parameter und Randbedingungen bei der Baugrubenherstellung. Darauf aufbauend sind mögliche Bauverfahren für die Herstellung von tiefen Baugruben von Interesse. Diverse Methoden unterscheiden sich in den erforderlichen Arbeitsschritten und Eigenschaften. Sie weisen unterschiedliche Vorund Nachteile und Einsetzbarkeiten auf. Im Rahmen dieser Arbeit werden geeignete Bauverfahren nach einer Recherche von Fachbüchern und Firmenunterlagen vorgestellt. Im Anschluss daran erfolgt eine Einteilung nach den zu Beginn erläuterten Einflussparametern. Bevor auf der Baustelle mit der Herstellung des Baugrubenverbaus begonnen werden kann, ist eine entsprechende Baustelleneinrichtung zu veranlassen. Hierfür sind einige Parameter zu beachten, welche im Zuge der Diplomarbeit herausgearbeitet werden. Dabei wurden relevante Fachliteratur, Gesetze und Verordnungen sowie Angaben von ausführenden Firmen herangezogen. Zum praktischen Verständnis des Themas werden drei Projekte mit tiefen Baugruben vorgestellt. Anhand der dazugehörigen Planungsunterlagen wird aufgezeigt, warum welche VerbauMethode bei den jeweiligen Bauvorhaben ausgewählt wurde. Für eine konkrete Aufgabenstellung gilt es eine geeignete Verbauart in der Planungsphase auszuwählen. Hierfür werden die bereits herausgearbeiteten Einflussparameter herangezogen. In der vorliegenden Diplomarbeit wird ein Verfahren zur Auswahl einer VerbauMethode auf Grundlage dieser Randbedingungen entwickelt. Ziel dabei ist es, eine Entscheidungsgrundlage für die Planungsphase zu definieren. Zum Schluss der Arbeit durchlaufen die bereits vorgestellten Bauprojekte das Auswahlverfahren. Dabei wird verdeutlicht, welche Verfahren eingesetzt bzw. nicht herangezogen werden können.For construction work below the ground level, a pit must be excavated in advance. With increasing depth of the Excavation bottom, the construction of the building pit plays an essential role. A suitable construction Method must be selected in the planning phase. It must be clarified in advance which influences are to be considered in a deep Excavation. Based on a literature review and on discussions with expert planners, this diploma thesis addresses relevant parameters and boundary conditions in pit construction. Based on this, possible construction Methods for the execution of deep Excavations are of interest. Possible procedures differ in required steps and performance. They have different ranges of application as well as pros and cons. In the context of this thesis, suitable construction Methods are presented after a research of reference books and company documents. This is followed by a classification according to the influencing parameters explained in the first section. Before construction work can start on-site, an appropriate site preparation and equipment must be arranged. Important parameters that need to be considered, are elaborated in the next section of this diploma thesis. Relevant literature, laws and regulations as well as information from specialized companies with practical know-how were used. To get a deeper understanding of the practical aspects, three projects with deep Excavations are presented. Based on the corresponding planning documents, it is explained why the construction Method was chosen for the respective project. For a specific task, it is important to select a suitable Excavation Method in the planning phase. For this purpose, the already elaborated influence parameters are used. A procedure for selecting the appropriate Method based on these boundary conditions has been developed and is presented in this document. The goal was to define a decision-making process as basis for the planning phase. In the end of the thesis, the previously presented construction projects go through the decision-making process to show which Methods can be used or not used in the specific settings.von Markus HellZusammenfassung in englischer SpracheTechnische Universität Wien, Diplomarbeit, 2019(VLID)338124
Kwang Ji Kim - One of the best experts on this subject based on the ideXlab platform.
-
Finite Element Analysis of Nonlinear Consolidation
1Co-Authors: Kwang Ji KimAbstract:220 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1982.A general finite element Method of solving nonlinear consolidation is presented for the unified treatment of saturated and partially saturated soils. Two sources of nonlinear material behavior are identified. The nonlinear material behavior under fully drained condition is represented by an elasto-plastic material model formulated in terms of effective stresses. For partially saturated soils, a constitutive model is presented for representing the compressibility of air-water mixture. The important role of surface tension between pore air and pore water is demonstrated. Surface tension effects are included in the proposed formulation in the form of a constant pressure difference between the pore air and pore water. A Method of determination of this pressure difference from laboratory experiments is presented. The proposed compressibility equation of air-water mixture shows stable monotonic decrease with the increasing applied pressure.The nonlinear consolidation finite element analysis is applied to the construction pore pressure problem using the general sequential construction and Excavation Method. This combined nonlinear consolidation model allows the influence of surface tension and the degree of saturation to be specified as input parameters in simulation of construction consolidation problems by virtue of the proposed equation of fluid compressibility. Results from the proposed model show considerably lower pore pressure development during the construction of earth dams in the partially saturated soils compared to fully saturated soils. Finally, a case simulation of Quebradona Dam using the proposed model is made and verified by comparing with the field measurements observed during the construction of the dam and appears to give reasonably accurate results.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD
Eftekhari Abbas - One of the best experts on this subject based on the ideXlab platform.
-
TUNNEL PORTAL INSTABILITY IN LANDSLIDE AREA AND REMEDIAL SOLUTION: A CASE STUDY
'Czech Technical University in Prague - Central Library', 2019Co-Authors: Farhadi Ayoublou Farhad, Taromi Majid, Eftekhari AbbasAbstract:The construction of tunnel portals in mountainous or slope areas often involves problems, which are closely related to factors, such as slope topography, geology, geotechnics, construction geometry and the tunnel Excavation Method. The activation of landslides or the acceleration of these events is one of the main challenges faced in the construction of tunnel portals. In this paper, we address the instability problem in Sabzkuh tunnel portal that has been excavated with a complex geological profile and high seismicity in Iran’s High Zagros region. The complexity and intense heterogeneity in geological formations, land acquisition problems and the lack of appropriate monitoring programs led to the instability of the tunnel portal. The Excavation process started without applying appropriate techniques for a ground stabilization. The use of inappropriate tunnel Excavation Methods for this unstable geological structure resulted in an activation of an old Solaghan fault and several collapses in the tunnel. Crossing the collapsed areas and reinforcing the tunnel portal took about 7 months and imposed heavy costs on the project. This case study deals with the importance of the choice of the site location, ground and underground monitoring, analysing and summarizing the collected data in order to prepare a geological model before and during the construction process
Farhadi Ayoublou Farhad - One of the best experts on this subject based on the ideXlab platform.
-
TUNNEL PORTAL INSTABILITY IN LANDSLIDE AREA AND REMEDIAL SOLUTION: A CASE STUDY
'Czech Technical University in Prague - Central Library', 2019Co-Authors: Farhadi Ayoublou Farhad, Taromi Majid, Eftekhari AbbasAbstract:The construction of tunnel portals in mountainous or slope areas often involves problems, which are closely related to factors, such as slope topography, geology, geotechnics, construction geometry and the tunnel Excavation Method. The activation of landslides or the acceleration of these events is one of the main challenges faced in the construction of tunnel portals. In this paper, we address the instability problem in Sabzkuh tunnel portal that has been excavated with a complex geological profile and high seismicity in Iran’s High Zagros region. The complexity and intense heterogeneity in geological formations, land acquisition problems and the lack of appropriate monitoring programs led to the instability of the tunnel portal. The Excavation process started without applying appropriate techniques for a ground stabilization. The use of inappropriate tunnel Excavation Methods for this unstable geological structure resulted in an activation of an old Solaghan fault and several collapses in the tunnel. Crossing the collapsed areas and reinforcing the tunnel portal took about 7 months and imposed heavy costs on the project. This case study deals with the importance of the choice of the site location, ground and underground monitoring, analysing and summarizing the collected data in order to prepare a geological model before and during the construction process
