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Η εργασία έχει πραγματοποιηθεί στην περιοχή της ΤΡΑΠΕΖΑ (ΔΙΑΚΟΦΤΟ). Κατά την διάρκεια της διαδικασίας είχαμε την ευκαιρία να μελετήσουμε όλες τις μεθόδους εκσκαφής της γαλαρίας και να παρθούν ορισμένα δείγματα για περαιτέρω εξέταση στο εργαστήριο. Έτσι σε γενικές γραμμές μπορούμε να πούμε ότι: Οι σχηματισμοί που συναντούμε είναι κυρίως από χαλικοπαγή - κροκαλοπαγή με στρώσεις μάργας και το αντίθετο. Δεν υπάρχει σημαντική παρουσία υπόγειων υδάτων, κυρίως συναντούμε μικρούς θύλακες νερού κατά την διάρκεια της εκσκαφής. Η μέθοδος που ακολουθήσαμε είναι η ΝΑΤΜ και σύμφωνα με αυτή έχουμε καταγράψει όλα τα αναγκαία μέτρα που έχουν ληφθεί. Επίσης πρέπει να αναφερθεί η γεωμηχανική ενοργάνωση που έχει εγκατασταθεί στην γαλαρία. Κλείνοντας όσον αναφορά τις εργαστηριακές δοκιμές που έχουν ολοκληρωθεί έχουμε καταλήξει στα κύρια φυσικά και μηχανικά χαρακτηριστικά της μάργας. Τα σχετικά αποτελέσματα των δοκιμών παρουσιάζονται αναλυτικά στην εργασία. This project has taken place in the area of TRAPEZA (Diakofto). During the process we had the opportunity to study all the excavation methods of the tunnel and to take some samples for further study in our lab. So in general lines we can say that: The formations that we encounter are mainly of gravel conglomerates with layers of marls and the opposite. There is not significant presence of underground water, mainly we introduce small pockets of water during the excavation process. The method that we followed is the NATM and according with this method we have recorded all the necessary measures that have been taken place. Also must be mentioned the geomechanical instrumentation that has been installed into the tunnel. In conclusion as far the lab tests we have conclude to the main physical and mechanical characteristics of the marl. A Thorough documentation of the obtained results is included in the project.

Nonlinear finite element method and Serendipity eight nodes element are used for determining of ground surface settlement due to tunneling. Linear element with elastic behavior is used for modeling of lining. Modified Generalized plasticity model with nonassociated flow rule is applied for analysis of a tunnel in Sao Paulo – Brazil. The tunnel had analyzed by Lades- model with 16 parameters. In this work modified Generalized Plasticity is used with 10 parameters, also Mohr-Coulomb model is used to analysis the tunnel. The results show good agreement with observed results of field data by modified Generalized Plasticity model than other models. The obtained result by Mohr-Coulomb model shows less settlement than other model due to excavation., {"references":["Shahrour, I. and Ghorbanbeigi, S. (1994). \"Calculation of tunnels in soft\nground.\" Numerical Method in Geotechnical Engineering, Smith (ed.),\nBalkema, Rotterdam.","Dias, D. and Kastner, R. (2000). \"Three Dimensional Simulation of Slurry\nShield Tunnelling.\" Geotechnical Aspects of Underground Construction\nin Soft Ground, Kusakabe, Fujita & Miyazaki (eds), Balkema,\nRotterdam.","Mroueh, H. and Shahrour, I. (2003). \"A Full 3-D Finite Element Analysis\nof Tunneling-Adjacent Structures Interaction.\" Computers and\nGeotechnics 30, 245-253.","Meguid, M. A. and Rowe, R. K. (2006). \"Stability of D-Shaped Tunnels\nin a Mohr-Coulomb Material under Anisotropic Stress Conditions.\"\nCanadian Geotechnical Journal, 43, 273-281.","Stallebrass, S. E., Jovicic, V. and Taylor, R. N.(1994). \"Short Term and\nLong Term Settlements around a Tunnel in stiff clay.\" Numerical\nMethod in Geotechnical Engineering, Smith (ed.), Balkema, Rotterdam.","Karakus, M. and Fowell, R. J. (2003). \"Effect of Different Tunnel Face\nAdvance Excavation on the Settlement by FEM.\" Tunnelling and\nUnderground Space Technology, 18, 513-523.","Dasari, G. R., Rawlings, C. G. and Bolton, M. D. (1995). \"Numerical\nModelling of a NATM Tunnel Construction in London Clay.\"\nGeotechnical Aspects of Underground Construction in Soft Ground,\nMair & Taylor (eds), Balkema, Rotterdam.","Clough, R. W. and Woodward, R. J. (1967). \"Analysis of embankment\nstresses and deformation.\" J. Solid Mech. Found. Div. ASCE, 93, 529-\n549.","Ghaboussi, J. and Pecknold, D. A. (1984). \"Incremental Finite Element\nAnalysis of Geometrically Altered Structures.\" International Journal for\nNumerical and Analytical Methods in Engineering, 20, 2051-2064.\n[10] Zienkiewicz, O. C., Leung, K. H. and Pastor, M. (1985). \"Simple Model\nfor Transient Soil Loading in Earthquake Analysis, I. Basic Model and\nits Application.\" International Journal for Numerical and Analytical\nMethod in Geomechanics, 9, 453-476.\n[11] Pastor, M., Zienkiewicz, O. C. and Leung, K. H. (1985). \"Simple Model\nfor Transient Soil Loading in Earthquake Analysis. II. Non-Associative\nModels for Sand.\" International Journal for Numerical and Analytical\nMethod in Geomechanics, 9, 477-498.\n[12] Chen, W. F. and Baladi, G. Y. (1985). Soil Plasticity Theory and\nImplementation, Developments in Geotechnical Engineering, Vol. 38,\nElsevier Science Publishers, U.S.A.\n[13] Pastor, M., Zienkiewicz, O. C. and Chan, A. H. C. (1990). \"Generalized\nPlasticity and the Modelling of Soil Behaviour.\" International Journal\nfor Numerical and Analytical Method in Geomechanics, 14, 151-190.\n[14] Liu, H. and Ling, H. I. (2002). \"A Sand Model Based on Generalized\nPlasticity.\" 15th ASCE Engineering Mechanics Conference, Columbia\nUniversity, New York, NY.\n[15] Liu, H. and Song, E. (2005). \"Seismic Response of Large Underground\nStructures in Liquefiable Soils Subjected to Horizontal and Vertical\nEarthquake Excitations.\" Computers and Geotechnics, 32 ,223-244.\n[16] Akhaveissy, A.H., Desai, C.S., Sadrnejad, S.A., Shakib, H.,\n\"Implementation and Comparison of a Generalized Plasticity and\nDisturbed State Concept for the Load-Deformation Behavior of\nFoundations\", Transaction D: Civil Engineering Vol. 16, No. 3, Sharif\nUniversity of Technology, Scientia Iranica, June 2009.\n[17] Akhaveissy, A.H. (2007). \"Evaluation of Tunnel-Structure Interaction\ndue to Strong ground movement.\" Ph.D. Thesis, Civil Engineering\nDepartment, Tarbiat Modares University, Tehran, Iran.\n[18] Azevedo, R. F., Parrerira, A. B. and Zornberg, J. G. (2002). \"Numerical\nAnalysis of a Tunnel in Residual Soils.\" Journal of Geotechnical and\nGeoenvironmental Engineering, 128(3), 227-236.\n[19] Potts, D. M. and Zdravkovic, L. (1999). Finite Element Analysis in\nGeotechnical Engineering, Published by Thomas Telford, First\nPublished."]}

The paper analyses the relationship between categories of excavation of certain tunnels. A relationship is given in natural and financial sense. Based on the analyzed relationship of forecasted and achieved categories of excavated tunnel, various approaches to this categorization and analyzed from the point of view of the designer, investor and contractor, depending on their approach to the goals of the construction as an investment project. Based on previous analyses, risk in categorization of tunnel excavations is explained as a key technological and key design risk in construction, especially for long tunnels in karsts. At the end, a model for managing risk in categorization of tunnel excavations between investor and contractor is given.

The paper analyses the costs in connection to the applied mode of blasting in the course of the excavation of the Grič Tunnel. The adjustment of blasting parameters has been done in accordance with dynamic of the works, the cost efficiency of undertaken blasting taking into consideration the change of the existing geological surroundings alongside the tunnel tube. The success of blasting and the price for the cost of drilling/blasting directly influences at the cycle of excavation of the tunnel that is to follow, by regarding the aspect of timing (dynamic aspect)as well as by influencing the entire investment for the tunnel in the end. Continued monitoring of the tunnel conditions as well as harmonization of blasting factors ensures optimal progress of the excavation with minimum price per metre of progress in the tunnel.

In this study, a 3D finite element model is applied to simulate the conventional procedure of tunnel excavation and lining. Both shallow and deep tunnels are considered in soils modelled with Mohr–Coulomb elasto-plastic constitutive equation. A polycentric tunnel cross-section with temporary lining and soil-nailing of the face excavation is studied. The numerical results show the influence of the soil properties and excavation procedures on face deformation and ground settlements. The model allows to evaluate the lining–soil interaction and the stress distribution in both the lining and the reinforcing structural elements.

Construction (or building), as the technological component in realising aconstruction or building industry project and arriving at the finished work, must be specifically structured and developed for every project. In this paper the authors analyse the implementation plans and the implementation itself of a construction project, the "Sveti Rok Tunnel" road tunnel through Mount Velebit, and compare the plans with the realised averige advance of tunnel excavation. This comparison enabled them to reach conclusions about selecting and planning engineering and technological methods (techniqes) for excavating long tunnels. The conclusions generally show that there is a risk factor involved in planning times and expenses for excavating especially long tunnels in karst regions.

This work is a discussion on the impact of blasting style, the type of explosive, the energy of ignition, the location of ignition and the plugging of blastholes on the efficiency of blasting of the blasthole perpendicular to the open surface.Experiments were carried out on the plexiglass models utilising low-energy explosions. Series of blasting was performed with specially produced capsules with explosive charge made of Pb-azide and PENT, 50 to 150 mg weight, in order to determine the rules and regularity of changes in the zone of plastic deformations in relation to concentration of explosive charge.Utilizing the models made of trikosal, funnel experiments were carried out changing the depth of explosive charge location. Specific volume of discharge was measured in relation to the depth of explosive charge. Measuring results were approximated by the second degree polinom."In situ" experiments were carried out on the construction-sites Tuhobić, Sljeme and Sopač. By method of funnel experiment, with blastholes 32 mm and 45 mm in diameter, several series of experiments with four types of explosives have been carried out. The following explosives were tested: amonal, detonal, methankamniktit and creox A1. The following relations were analysed: specific break-off related to depth of the gravity centre of explosive charge, specific break off related to plug length, and the depth of blasted funnel related to gravity centre depth of explosive charge. Based on these data it is easy to conclude which one of the tested explosives gives the best blasting effects.

The paper presents a constitutive model for argillaceous rocks, developed within the framework of elastoplasticity, that includes a number of features that are relevant for a satisfactory description of their hydromechanical behaviour: anisotropy of strength and stiffness, behaviour nonlinearity and occurrence of plastic strains prior to peak strength, significant softening after peak, time-dependent creep deformations and permeability increase due to damage. Both saturated and unsaturated conditions are envisaged. The constitutive model is then applied to the simulation of triaxial and creep tests on Callovo-Oxfordian (COx) claystone. Although the main objective has been the simulation of the COx claystone behaviour, the model can be readily used for other argillaceous materials. The constitutive model developed is then applied, via a suitable coupled hydromechanical formulation, to the analysis of the excavation of a drift in the Meuse/Haute-Marne Underground Research Laboratory. The pattern of observed pore water pressures and displacements, as well as the shape and extent of the damaged zone, are generally satisfactorily reproduced. The relevance and importance of rock anisotropy and of the development of a damaged zone around the excavations are clearly demonstrated.

Nagli pomaci u tlu mogu dovesti do oštećenja armiranobetonskih građevina. Takvi pomaci mogu između ostalog biti uzrokovani gradnjom tunela, pa se utjecaj takve gradnje treba uzeti u obzir u postupku projektiranja građevina. U ovom se radu na primjeru postojeće bolničke zgrade analiziraju konstrukcijska oštećenja armiranobetonske građevine uslijed naglih pomaka tla. Kako bi se dobili što točniji podaci za potrebe analiza, primijenjen je multidisciplinarni pristup radi povezivanja raznih inženjerskih disciplina koje su sudjelovale u ovom istraživanju., Structural damages to RC (Reinforced concrete) buildings occasionally occur as a consequence of sudden ground movements. One of these is effect of tunnel excavation on the structures and the design process should be carried out by taking the effect into account. In this study, the structural damages caused by the impact of sudden movement emanating at the ground were investigated for a selected hospital building. Within the scope of this study, it was aimed to obtain the most accurate data by combining different engineering disciplines through a comprehensive approach.