Construction of braced excavations in major urban areas has increased over the last few decades. It is a major concern of the designer to limit ground movement around an excavation in order to prevent damage to adjacent structures, utilities and roads. Existing design methods can accurately predict ground and wall movement of a braced excavation, but the calculations become complex when multiple construction stages are considered, or if different design schemes are compared. This thesis presents an interactive personal computer program (called MOVEX) to facilitate braced excavation design. Using input variables for wall stiffness, strut stiffness, and strut spacing, MOVEX includes four design options that allow the designer to adjust the variables in order to develop the optimal bracing design. Details of the design theory, input and output data, and a user's guide are included in this thesis. In addition, the settlement of sand due to pile driving was investigated. A predictive method is presented that relates sand densification to the ground acceleration caused by pile driving. / Master of Science

The personal computer program MOVEX, a program for the design of structurally supported excavations to limit X lateral ground movements in clay soils, was revised and updated. A key element in the program, the method of determining factor of safety against basal heave, was fully rewritten. Seven case histories were examined to evaluate the program capabilities in predicting movements. Two important improvements to the program include adding allowances for possible anisotropic strength variations in the soil layers, and for wall movements caused by excavation before supports are added to the wall. The latter issue is relevant inasmuch as such movements are present in almost all excavations to one degree or another. The program output was also updated using a streamlined and more informative format. Disclaimer statements were added to certain areas to notify the user of program limitations. Movement calculation methods were improved by removing several errors and adding a linear interpolation feature which eliminates our earlier problem with jumps in predictions as certain parameter horizons were passed. Finally, the Fortran program was reorganized and comment statements were added to provide a more flowing and readable style, and a new User's Guide was developed to reflect the new program. / Master of Science

A fundamental element of the observational method in geotechnical engineering practice is the utilization of a carefully laid out performance monitoring system which provides rapid insight of critical behavioral trends of the work. Especially in tunnels, this is of paramount importance when the contractual arrangements allow an adaptive tunnel support design during construction such as the NATM approach. Utilization of measurements can reveal important aspects of the ground-support interaction, warning of potential problems, and design optimization and forecasting of future behavior of the underground work. The term back-analysis involves all the necessary procedures so that a predicted simulation yields results as close as possible to the observed behavior. This research aims in a better understanding of the back-analysis methodologies by examining both simplified approaches of tunnel response prediction but also more complex numerical methods. Today a wealth of monitoring techniques is available for tunnel monitoring. Progress has also been recorded in the area of back-analysis in geotechnical engineering by various researchers. One of the most frequently encountered questions in this reverse engineering type of work is the uniqueness of the final solution. When possible errors are incorporated during data acquisition, the back analysis problem becomes formidable. Up to the present, various researchers have presented back-analysis schemes, often coupled with numerical methods such as the Finite Element Method, and in some cases the more general approach of neural networks has been applied. The present research focuses on the application of back-analysis techniques that are applicable to various conditions and are directly coupled with a widely available numerical program. Different methods are discussed and examples are given. The strength and importance of global optimization is introduced for geotechnical engineering applications along with the novel implementation of two global optimization algorithms in geotechnical parameter identification. The techniques developed are applied to the back-analysis of a modern NATM highway tunnel in China and the results are discussed. / Ph. D.

In the present research a highway twin tunnel project completed in Japan in 1998 is used as a case study to verify results of numerical analyses with measurement data. Each of the tunnels had approximately 1.1 km of length. For this project a wide geometry of approximately 18.0 m was selected by the designers to facilitate three lanes per tunnel. A sequential tunneling technique known in Japan as the "TBM pilot and enlargement method" was used along with NATM principles. The tunnel was used as a reference project, involving performance testing and extensive monitoring in order to verify and standardize support requirements for other tunnels excavated under similar geologic conditions in the Tomei II expressway. The tunnel was excavated in a region consisting mainly of soft sedimentary rocks, such as locally weathered sandstone, underlain by interbedded sandstone and mudstone. Due to observed non symmetric deformations and loads in the tunnel, the distinct element and the convergence-confinement methods were used during the numerical simulations. A parametric analysis was performed initially in a pseudo-continuum approach to study the behavior of the wide tunnel geometry under various conditions. The effects of rock mass elastic modulus, in situ Ko ratio and boundary conditions are discussed. More complex parametric studies were performed in a stochastically generated model by using joint spatial data from geotechnical investigations. The Barton-Bandis constitutive law was assumed for the behavior of the joints. The sensitivity of the ground "characteristic curves" was examined by statistical variation of the joint shear strength parameters. A final simulation using the code UDEC and the convergence-confinement method yields interesting results which are comparable to the monitored data. / Master of Science

Geographically located materials are used by the archaeology to analyze and explain the socio-cultural aspects of ancient life. Thus, Geographical Information Systems (GIS) have started to be used in archaeology for many applications. Although, cooperation of GIS and archaeology is considered as beneficial, it has become insufficient to meet the requirements of archaeologists about excavation study. Therefore, the aim of this thesis is to develop Spatial Decision Support System (SDSS) which includes both the GIS tools and analyses and / analytical modeling capabilities in order to satisfy the needs of archaeologists. Moreover, to develop a specialized system for specific archaeological excavation site is aimed. In this study, Kaunos is selected as a case study area and in order to furnish this aim, firstly, needs of archaeologists working in the excavation study of Kaunos are analyzed. Secondly, GIS tools and analyses are determined which meet the requirements of archaeologists. Finally, SDSS for Kaunos Archaeological Excavation Site is developed. It is composed of four components namely / Database Management, Model Management, Dialog Management and Stakeholder Components. Analyses are conducted under the Model Management Component and results are visualized in Dialog Management Component. Result maps help and assist archaeologists in terms of interpreting and examining the socio-cultural, economical and demographical characteristics of Kaunos.

Due to space limitations in urban areas, underground construction has become a common practice worldwide. When using deep excavations, excessive lateral movements are a major concern because they can lead to significant displacements and rotations in adjacent structures. Therefore, accurate predictions of lateral wall deflections and surface settlements are important design criteria in the analysis and design of excavation support systems. This research shows that the current design methods, based on plane strain analyses, are not accurate for designing excavation support systems and that fully three-dimensional (3D) analyses including wall installation effects are needed. A complete 3D finite element simulation of the wall installation at the Chicago and State Street excavation case history is carried out to show the effects of modeling: (i) the installation sequence of the supporting wall, (ii) the excavation method for the wall, and (iii) existing adjacent infrastructure. This model is the starting point of a series of parametric analyses that show the effects of the system stiffness on the resulting excavation-related ground movements. Furthermore, a deformation-based methodology for the analysis and design of excavation support systems is proposed in order to guide the engineer in the different stages of the design. The methodology is condensed in comprehensive flow charts that allow the designer to size the wall and supports, given the allowable soil distortion of adjacent structures or predict ground movements, given data about the soil and support system.

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.

No / Excavation at a cropmark enclosure in the Upper Severn Valley was undertaken to try and obtain material from which to provide relative and absolute dating for the site. Lying within an area rich in Neolithic and Bronze Age archaeology and in close proximity to a proven long barrow, the conventional later prehistoric date postulated for the enclosure was questioned. Excavation proved the site to have been a ditched enclosure with internal bank and a possible gate structure. Post-pits ran inside the bank. Finds were few but radiocarbon dates from the floor of the ditch proved the early Neolithic credentials of the monument which seemed to have continued in use for at least some 500 years.

Thesis is submitted in partial fulfilment of the requirements for the degree of Master of Science in Engineering to the Faculty of Engineering and the Built Environment, School of Mining Engineering, University of the Witwatersrand, Johannesburg, 2017 / Boring of shafts and tunnels in hard rock mines is more prevalent in recent years in South Africa. This normally takes place under substantial stress conditions, where fracturing of rock occurs around the boundaries and ahead of advancing faces of excavations. Fracturing can have a significant impact on boring activities, in some instances causing sidewall spalling which can be extensive, with machine grippers unable to reach the sidewalls. In brittle rock, these fractures are commonly extensional in nature. This research has been undertaken to predict the initiation of extension fractures and their orientations ahead of machine driven tunnels. Furthermore, it will help to assess the stability of the excavations, by evaluating the potential for slab/plate failures. This was based on the typical in situ stress fields for underground deep level mines. The numerical analyses involved the generation of different plots:  Principal stress contour plots, depicting stress distributions around and ahead of tunnel excavation, using cutting planes;  Isosurfaces, showing zones of extension or potential extents of fracturing, applying the extension strain criterion; and  Trajectory ribbons, to demonstrate the orientations of fractures. Based on the results of the stress analyses, potential slab or plate formation was determined. It was noted that the fracture zone is a function of a tunnel size. For instance, a four-metre diameter tunnel is less likely to give boring problems than an eight-metre diameter tunnel. The failure of the tunnels was predicted by employing slab analysis methods. An eight-metre diameter tunnel had slenderness ratio as low as 22.3 as compared with a four-metre diameter tunnel with a slenderness ratio of 27. Looking at buckling stress versus slenderness ratio, this translates to buckling stress values of above 100 MPa for an eight-metre tunnel and to values just below 50 MPa for a four-metre tunnel. The outcome of the research gives a clear indication that boring activities could be undertaken under severe conditions. This could be detrimental to the cutter head, since large slabs and blocks could be encountered during boring. The results of this research can be beneficial in the evaluation of boring conditions prior to and during boring activities. / MT2018

This thesis presents the results from archaeological test excavations at site 5GN1.2. The focus of this research is to evaluate Stiger's Late Prehistoric settlement-subsistence hypothesis. According to this hypothesis, post-3000 B.P. occupations of the Upper Gunnison Basin were limited to logistically organized big-game hunting forays originating from residential camps located outside of the basin. Since Stiger's model is based on Binford's forager-collector continuum model, archaeological test implications of his hypothesis include hunter-gatherer settlement mobility, site types, feature types, artifact assemblage characteristics, and the organization of lithic technology. Test excavations at 5GN1.2 revealed intact archaeological deposits reflecting aboriginal occupation during the Late Prehistoric between about 3000 and 1300 B.P. Late Prehistoric features include four hearths associated with abundant debitage, small-game faunal remains, burnt seeds, and lithic tools. Identified lithic tools include ground stone, projectile point fragments, cores, and bifaces. Individual flake attribute analysis of the debitage assemblage provides evidence lithic reduction activities were dominated by bifacial reduction of local and non-local raw materials. Archaeological evidence rules out site 5GN1.2 as a Late Prehistoric logistical big-game hunting site. Site 5GN1.2 contains all the hallmarks of a residential base camp, including constructed hearths, rock art, evidence of plant resource processing, small-game procurement, comparatively high tool diversity, high proportion of locally available tool-stone, late-stage tool manufacture, and tool maintenance debitage. Site 5GN1.2 likely served as a short-term residential base camp occupied by whole family groups during the Late Prehistoric. The Late Prehistoric occupations of site 5GN1.2 represent a more diverse settlement-subsistence adaptation than envisioned by Stiger's culture history. Some hunter-gatherers may have occupied the UGB on long-range logistical big-game hunting forays, but at 5GN1.2 this is simply not the case. This lithic technology research project represents the first published comprehensive debitage analysis of an archaeological component at 5GN1.2 and 5GN1. These results and data can serve as a database for later archaeological research within the UGB.