Στην παρούσα Διατριβή παρουσιάζονται τα έργα του συστήματος αντιστήριξης για την κατασκευή του Υπογείου χώρου του τμήματος του νέου κτιρίου, του συγκροτήματος της πρώην «Αγοράς Αργύρη» που ευρίσκεται στη Πάτρα, επί των οδών Αγ. Ανδρέου – Καψάλη – Ζαΐμη, που κατασκευάστηκε στα πλαίσια του έργου «Ανακαίνιση – Ανακατασκευή Αγοράς Αργύρη Πατρών», από το Δήμο Πατρέων. Στα πλαίσια της συνολικής αυτής παρουσίασης των έργων αντιστήριξης, παρουσιάζεται κατ’ αρχάς η τεκμηρίωση του τρόπου επιλογής της μεθόδου αντιστήριξης, που έγινε με μεταλλικό πασσαλότοιχο καθώς και στοιχεία της μελέτης που έγινε για τη διαστασιολόγηση αυτής. Περιγράφεται η κατασκευαστική διαδικασία και η αλληλουχία των φάσεων κατασκευής του συνδυασμένου συστήματος της βαθιάς αντιστηριγμένης εκσκαφής, που περιλαμβάνει : Γενικές εκσκαφές, έως βάθους -1,80 μ. για την απομάκρυνση επιφανειακών σκληρών στρώσεων από συμπυκνωμένο αμμοχάλικο. Εγκατάσταση - κατασκευή μεταλλικού πασσαλότοιχου, με παράλληλη και συστηματική παρακολούθηση των σχετικών εργασιών της έμπηξης αυτών. Τοποθέτηση μεταλλικού σκελετού (χωροδικτυώματος), σε κατάλληλη διάταξη στην κεφαλή του πασσαλότοιχου για την παρεμπόδιση των οριζοντίων μετακινήσεων του συστήματος αντιστήριξης. Τμηματικές εκσκαφές και παράλληλη τμηματική κατασκευή πρόπλακας από οπλισμένο σκυρόδεμα στη βάση της θεμελίωσης του κτιρίου. Σύγχρονη και συστηματική παρακολούθηση της λειτουργίας του συστήματος αντιστήριξης μέσω ήδη τοποθετημένων κλισιμέτρων, αλλά και των παρακείμενων, περιμετρικά της εκσκαφής υπαρχόντων κτιρίων, μέσω των ήδη τοποθετημένων αποκλισιομέτρων. Απεγκατάσταση - εξολκή πασσαλοσανίδων μεταλλικού πασσαλότοιχου με παράλληλη και συστηματική ενόργανη παρακολούθηση των σχετικών εργασιών της εξολκής αυτών. Όλες οι φάσεις της κατασκευής συνοδεύονται με φωτογραφικό υλικό. Παρουσιάζονται τα αποτελέσματα αριθμητικής προσομοίωσης των φάσεων της βαθιάς αντιστηριγμένης εδαφικής εκσκαφής και η σύγκριση τους με αποτελέσματα επί τόπου μετρήσεων. Η διεξαγωγή των αναλύσεων έγινε με τη χρήση του κώδικα πεπερασμένων στοιχείων PLAXIS 2D Foundation (Version 8.6). Παρουσιάζονται τα τεχνικά και διαδικαστικά προβλήματα που παρουσιάστηκαν κατά την εγκατάσταση – λειτουργία και απεγκατάσταση του συστήματος αντιστήριξης. Τέλος, προκύπτουν και διατυπώνονται τα ακόλουθα γενικά συμπεράσματα :  Η προσωρινή αντιστήριξη βαθιών εκσκαφών σε δομημένο αστικό περιβάλλον με χρήση μεταλλικών πασσαλοσανίδων που εγκαθίστανται με δονητικό πασσαλοπήχτη, είναι δυνατή, σε περιπτώσεις που η στρωματογραφία δεν περιλαμβάνει αμμοχαλικώδη στρώματα μεγάλου πάχους και με την προϋπόθεση ότι γίνεται συστηματική παρακολούθηση της έντασης των παραγόμενων εδαφικών ταλαντώσεων κατά την έμπηξη και εξολκή των πασσαλοσανίδων.  Η εξολκή των πασσαλοσανίδων καθίσταται ιδιαίτερα δυσχερής ή και αδύνατη, όταν οι εγκατεστημένες πασσαλοσανίδες παρουσιάζουν αποκλίσεις από την κατακόρυφο.  Η πολύμηνη παραμονή των πασσαλοσανίδων σε παρόμοιας σύστασης εδάφη, με αυτά του έργου (μαλακές Άργιλοι κλπ.), δημιουργούν συνθήκες ανάπτυξης χημικών συνδέσμων μεταξύ αργίλου και χάλυβα δυσχεραίνοντας την εξολκή αυτών.  Είναι δυνατή η ρεαλιστική εκτίμηση της αναμενόμενης συμπεριφοράς του συστήματος προσωρινής αντιστήριξης και των εδαφικών μαζών (και κατασκευών που περιβάλλουν την  εκσκαφή) με βάση τα αποτελέσματα αριθμητικών αναλύσεων με εμπορικά διαθέσιμους κώδικες πεπερασμένων στοιχείων.  Στην περίπτωση του εξεταζόμενου έργου παρατηρήθηκε ικανοποιητική συμφωνία μεταξύ της μετρηθείσας και υπολογισθείσας συμπεριφοράς, όσον αφορά τις μετακινήσεις τόσο του συστήματος αντιστήριξης όσο και των γειτονικών οικοδομών. / In this project are presented the works of Support system for the construction of underground part of the new building complex of the former Market Argyri’s, located in Patras , on the building square of St. Andrew st. – Kapsalis st. – Zaimi st., witch built under the project "Renovation - Reconstruction Argyri’s Market of Patras" by the Municipality of Patras. As part of this total presentation of the project elements, presented first, the documentation of how to choose the method of support, made of metal sheeting and details of the study for sizing it. Describe the manufacturing process and the sequence of construction of the combined system for the support of deep excavation, including: General excavations, to a depth of -1.80 m, to remove surface layers of concentrated hard gravel, Installation - Construction of Metal Sheeting, while monitoring and systematic work on the penetration of these, Mounting frame (space frame), to a suitable device at the head of the sheeting to prevent horizontal movement of this, Partial excavations with parallel partial construction of concrete reinforced slabs, under foundation at the base of the building, Modern and systematic monitoring of the system operation with already installed gradiometers, and the adjacent, around the excavation of existing buildings, through the already installed inclinometer. Uninstall - metal sheeting piles haul-offs, while instrumental and systematic monitoring of the work of these haul-offs. All phases of construction are accompanied by photographs. It also presents the results of numerical simulation phases of the support deep excavated soil and comparison with results on-site measurements. The analysis was carried out using the finite element code PLAXIS 2D Foundation (Version 8.6). A comparison of system behavior that occurs through the roof measurements and calculated behavior was made through numerical simulation. Present the technical and procedural problems encountered during installation - operation and uninstalling the system of support. Finally, obtained and made the following general conclusions: The temporary shoring of deep excavations in urban environment built using steel sheet piles installed with vibratory passalopichti is possible, where the stratigraphy does not include ammochalikodi layers thick and provided with systematic monitoring of the intensity of vibrations produced by the soil punching and puller of the sheet piling. The puller of the sheet piling is very difficult or impossible when the installed sheet piles are deviations from the vertical. The months – long stay of the sheet piles in similar soil composition, with those of this project (soft clays etc.), create conditions for development of chemical bands between clay and steel, hindering the puller them. It is possible a realistic estimate of the expected behavior of a temporary roof and land masses (and structures surrounding the excavating) based on the results of numerical analysis with commercially available finite element codes. In the case of the test project observed satisfactory agreement between the measured and the calculated behavior with regard to movements of both the roof and the adjacent buildings.

This dissertation describes enhancements made to the finite element program, SAGE, and research on the performance of deep excavations. SAGE was developed at Virginia Tech for analysis of soil-structure interaction problems (Morrison, 1995). The purpose of the work described in this text with SAGE was to increase the capabilities of the program for soil-structure analysis. The purpose of the research on deep excavations was to develop a deeper understanding of the behavior of excavation support systems. The significant changes made to SAGE during this study include implementation of Biot Consolidation, implementation of axisymmetric analysis, and creation of a steady state seepage module. These changes as well as several others are described. A new manual for the program is also included. A review of published studies of deep excavation performance and recent case histories is presented. Factors affecting the performance of excavation support systems are examined, and performance data from recent published case histories is compared to data from Goldberg et al.'s 1976 report to the Federal Highway Administration. The design, construction, and performance of the deep excavation for the Dam Number 2 Hydroelectric Project is described. Finite element analyses of the excavation that were performed with SAGE are presented and discussed. / Ph. D.

No description available.

One of the most common retaining systems for deep excavations is by supporting a wall with multiple levels of anchors. In densely built urban areas, preventing soil movement with such a system can be very costly. Additionally, anchored walls are assumed and forced to act independently during design calculations, thus fail to take the advantage of the rigidity of the whole system at the corners of the excavation area. An alternative support system that uses the entire system is bracing of the walls with struts. But such a system greatly hinders construction space. In this research, a new type of supporting system has been investigated by performing a parametric study in finite element analyses program. New system is a single ring at each support level, supporting the system at several locations. A comparative study has been undertaken between the conventional systems and the new system in both 2D and 3D. PLAXIS finite element analysis software was used for the analyses. The primary aim was to investigate the structural and geotechnical performance of the arch supported system. The study revealed that the new system provides improvement for specific cases and can be considered as an alternatve support system for such cases.

In this thesis, hypothetical cases of in-situ walls, that are supported at one, two and four levels, as well as cantilever walls, are analyzed using plane strain and 3D finite element programs. A parametric study is performed by varying the soil stiffness. Deflection, moment, anchor loads and effective lateral earth pressures acting on the walls are examined to understand corner effect. Comparisons are made between plane strain and 3D without corner analysis results to confirm that two programs yield similar results. Moreover, two deep excavation case histories namely: i) Ankara &Ccedil / ankaya trade center and residence and, ii) Ekol construction are analyzed using calibrated models. Calibrations of the models are made using inclinometer data. In hypothetical models, it is found that corner effects on deflections diminish after 20m distance from the corner for excavations that are 8m and 12m deep. Corner effects on deflection decrease as elastic modulus of soil or stiffness of the system increase. Moment diagram pattern changes along the excavation side in cantilever case study. Moment diagram obtained around a corner in 3D analysis and diagrams obtained from the plane strain analyses by modeling the corner as a strut are quite similar. The anchor loads increase until 10-15m distance from the corner. After this distance they become nearly constant. In the analysis of case histories, a trial error solution is adopted to fit the deformed shape of piled wall obtained from 3D analysis to the deformations recorded by inclinometers. These results are compared with the results of plane strain analyses. Ankara-&Ccedil / ankaya project is solved by modeling the corner as strut in plane strain analyses. Results of this analyze agrees with field monitoring data, indicating that corner effects could be simulated by modeling the perpendicular pile wall as a strut in plane strain analysis.

Deep excavations have been used worldwide for underground construction, but they also alter the ground conditions and induce ground movements which might cause risks to adjacent infrastructure. Field measurements are normally carried out during excavations to ensure their safety, and also provide valuable data to calibrate the results from the numerical analysis which is an effective way to investigate the performance of deep excavations. This thesis is concerned with evaluating the capability of advanced finite element analysis in reproducing various aspects of observed deep excavation behaviour in the field through back analysis of case histories. The finite element model developed considers both geotechnical and structural aspects such as (i) detailed geometry of the excavation and retaining structures, (ii) realistic material models for the soil, structures and the soil-structure interface, and (iii) correct construction sequences. Parametric studies are conducted first based on a simplified square excavation to understand the effect of several important aspects, e.g. (i) the merit of shell or solid elements to model the retaining wall, (ii) the effect of construction joints in the retaining wall, (iii) the effect of the operational stiffness of concrete structural components due to cracks, (iv) the thermal effect of concrete beams and floor slabs during curing process and due to variation of ambient temperature, (v) the effect of soil-structure interface behaviour, and (vi) the effect of stiffness and strength properties of the soil. Two more complex case histories are then investigated through fully 3D analyses to explore the influence of various factors such as (i) neglecting the small-strain stiffness nonlinearity in the soil model, (ii) the selected K_0 value to represent the initial stress state in the ground, (iii) the appropriate anisotropic wall properties to consider the joints in the diaphragm wall, (iv) the parameters governing the settlements of adjacent buildings and buried pipelines, (v) the effectiveness of ground improvement on reducing the building settlement, (vi) the variation of construction sequences, (vii) the effectiveness of earth berms, and (viii) ignoring the openings in the floor slabs. This research has strong practical implications, but cautions should also be taken in applications, e.g. element types and parameter selection.

La presente investigación se originó por la necesidad de demostrar que las fallas en el enfoque de la normativa ambiental en el manejo de los residuos sólidos de las actividades de construcción y demolición generan incrementos considerables en el presupuesto de obra de una edificación, pues la normativa ambiental está enfocada hacia residuos sólidos que se generan en menores cantidades a comparación del material extraído producto de la excavación masiva, debido a ello el objetivo de la investigación es orientar la normativa ambiental en el manejo de residuos sólidos de las actividades de construcción y demolición en edificaciones hacia residuos sólidos y materiales naturales generados en grandes cantidades como es el caso del material excavado. La metodología de investigación es de tipo aplicada y el nivel de investigación es descriptivo-correlacional. Se obtuvieron como resultados que el material excavado es un material natural que se puede prescindir del uso de las Empresa Prestadora de Servicios de Residuos Sólidos y que las Empresas Prestadoras de Servicios de Residuos Sólidos no cuentan con capacidad instalada suficiente para poder cumplir con el rendimiento programado para que un proyecto sea viable. This research arises from the need to demonstrate that the flaws in the approach to environmental regulations in the management of solid waste from construction and demolition activities generate substantial increases in budget work of a building, for environmental regulations It is focused on solid waste generated in smaller amounts to comparing the extracted material product of the mass excavation, due to that the aim of the research is to guide environmental regulations on solid waste management activities of construction and demolition buildings to solid waste and natural materials generated in large quantities as is the case of excavated material. The research methodology is applied type and level of research is descriptive-correlational. Results were obtained as excavated material is natural materials that can dispense with the use of a service provider and Solid Waste Services Companies the Solid Waste not have enough installed capacity to meet the scheduled performance for a project to be viable.