<p>This dissertation deals with (1) experimental measurements on petrophysical reservoir engineering and morphological properties of Ekofisk chalk, (2) numerical simulation of core flood experiments to analyze and improve relative permeability data, (3) stochastic reconstruction of chalk samples from limited morphological information, (4) extraction of pore space parameters from the reconstructed samples, development of network model using pore space information, and computation of petrophysical and reservoir engineering properties from network model, and (5) development of 2D and 3D idealized fractured reservoir models and verification of the applicability of several widely used conventional upscaling techniques in fractured reservoir simulation. </p><p>Experiments have been conducted on eight Ekofisk chalk samples and porosity, absolute permeability, formation factor, and oil-water relative permeability, capillary pressure and resistivity index are measured at laboratory conditions. Mercury porosimetry data and backscatter scanning electron microscope images have also been acquired for the samples. </p><p>A numerical simulation technique involving history matching of the production profits is employed to improve the relative permeability curves and to analyze hysteresis of the Ekofisk chalk sample. The technique was found to be a powerful tool to supplement the uncertainties in experimental measurements. </p><p>Porosity and correlation statistics obtained from backscatter scanning electron microscope image are used to reconstruct microstructures of chalk and particulate media. The reconstruction technique involves a simulated annealing algorithm, which can be constrained by an arbitrary number of morphological parameters. This flexibility of the algorithm is exploited to successfully reconstruct particulate media and chalk samples using more that one correlation function. A technique based on conditional simulated annealing has been introduced for exact reproduction of vuggy porosity in chalk in the form of foraminifer shells. A hybrid reconstruction technique that initialized the simulated annealing reconstruction with input generated using the Gaussian random field model has also been introduced. The technique was found to accelerate significantly the rate of convergence of the simulated annealing method. This finding is important because the main advantage of the simulated annealing method, namely its ability to impose a variety of reconstruction constraints, is usually compromised by its very slow rate of convergence.</p><p>Absolutely permeability, formation factor and mercury-air capillary pressure are computed from simple network models. The input parameters for the network models were extracted from a reconstructed chalk sample. The computed permeability, formation factor and mercury-air capillary pressure correspond well with the experimental data. The predictive power of a network model for chalk is further extended through incorporating important pore-level displacement phenomena and realistic description of pore space geometry and topology. Limited results show that the model may be used to compute absolute and relative permeabilities, capillary pressure, formation factor, resistivity index and saturation exponent. The above findings suggest that the network modeling technique may be used for prediction of petrophysical and reservoir engineering properties of chalk. Further works are necessary and an outline is given with considerable details.</p><p>Two 2D, one 3D and a dual-porosity fractured reservoir models have been developed and an imbibition process involving water displacing oil is simulated at various injection rates and with different oil-to-water viscosity ratios using four widely used conventional upscaling techniques. The upscaling techniques are the Kyte & Berry, Pore Volume Weighted, Weighed Relative Permeability, and Stone. The results suggest that the upscaling of fractured reservoirs may be possible using the conventional techniques. Kyte & Berry technique was found to be the most effective in all situations. However, further investigations are necessary using realistic description of fracture length, orientation, connectivity, aperture, spacing, etc. </p> / Paper 3,4 and 5 reprinted with kind persmission of Elsevier Science, Science Direct.

<p>This research project studies the feasibility of developing and applying an integrated field simulator to simulate the production performance of an entire oil or gas field. It integrates the performance of the reservoir, the wells, the chokes, the gathering system, the surface processing facilities and, whenever applicable, gas and water injection systems.</p><p>The approach adopted for developing the integrated simulator is to couple existing commercial reservoir and process simulators using available linking technologies. The simulators are dynamically linked and customized into a single hybrid application that benefits from the concept of open software architecture. The integrated field simulator is linked to an optimization routine developed based on the genetic algorithm search strategies. This enables optimization of the system at field level, from the reservoir to the process. Modeling the wells and the gathering network is achieved by customizing the process simulator.</p><p>This study demonstrates that the integrated simulation improves currentcapabilities to simulate the performance of an entire field and optimize its design. This is achieved by evaluating design options including spread and layout of the wells and gathering system, processing alternatives, reservoir development schemes, and production strategies.</p><p>Effectiveness of the integrated simulator is demonstrated and tested through several field-level case studies that discuss and investigate technical problems relevant to offshore field development. The case studies cover topics such as process optimization, optimum tie-in of satellite wells into existing process facilities, optimal well location, and field layout assessment of a high pressure high temperature deepwater oil field.</p><p>Case study results confirm the viability of the total field simulator by demonstrating that the field performance simulation and optimal design were obtained in an automated process with reasonable computation time. No significant simplifying assumptions were required to solve the system and tedious manual data transfer between simulators, as conventionally practiced, was avoided.</p>

This dissertation deals with (1) experimental measurements on petrophysical reservoir engineering and morphological properties of Ekofisk chalk, (2) numerical simulation of core flood experiments to analyze and improve relative permeability data, (3) stochastic reconstruction of chalk samples from limited morphological information, (4) extraction of pore space parameters from the reconstructed samples, development of network model using pore space information, and computation of petrophysical and reservoir engineering properties from network model, and (5) development of 2D and 3D idealized fractured reservoir models and verification of the applicability of several widely used conventional upscaling techniques in fractured reservoir simulation. Experiments have been conducted on eight Ekofisk chalk samples and porosity, absolute permeability, formation factor, and oil-water relative permeability, capillary pressure and resistivity index are measured at laboratory conditions. Mercury porosimetry data and backscatter scanning electron microscope images have also been acquired for the samples. A numerical simulation technique involving history matching of the production profits is employed to improve the relative permeability curves and to analyze hysteresis of the Ekofisk chalk sample. The technique was found to be a powerful tool to supplement the uncertainties in experimental measurements. Porosity and correlation statistics obtained from backscatter scanning electron microscope image are used to reconstruct microstructures of chalk and particulate media. The reconstruction technique involves a simulated annealing algorithm, which can be constrained by an arbitrary number of morphological parameters. This flexibility of the algorithm is exploited to successfully reconstruct particulate media and chalk samples using more that one correlation function. A technique based on conditional simulated annealing has been introduced for exact reproduction of vuggy porosity in chalk in the form of foraminifer shells. A hybrid reconstruction technique that initialized the simulated annealing reconstruction with input generated using the Gaussian random field model has also been introduced. The technique was found to accelerate significantly the rate of convergence of the simulated annealing method. This finding is important because the main advantage of the simulated annealing method, namely its ability to impose a variety of reconstruction constraints, is usually compromised by its very slow rate of convergence. Absolutely permeability, formation factor and mercury-air capillary pressure are computed from simple network models. The input parameters for the network models were extracted from a reconstructed chalk sample. The computed permeability, formation factor and mercury-air capillary pressure correspond well with the experimental data. The predictive power of a network model for chalk is further extended through incorporating important pore-level displacement phenomena and realistic description of pore space geometry and topology. Limited results show that the model may be used to compute absolute and relative permeabilities, capillary pressure, formation factor, resistivity index and saturation exponent. The above findings suggest that the network modeling technique may be used for prediction of petrophysical and reservoir engineering properties of chalk. Further works are necessary and an outline is given with considerable details. Two 2D, one 3D and a dual-porosity fractured reservoir models have been developed and an imbibition process involving water displacing oil is simulated at various injection rates and with different oil-to-water viscosity ratios using four widely used conventional upscaling techniques. The upscaling techniques are the Kyte &amp; Berry, Pore Volume Weighted, Weighed Relative Permeability, and Stone. The results suggest that the upscaling of fractured reservoirs may be possible using the conventional techniques. Kyte &amp; Berry technique was found to be the most effective in all situations. However, further investigations are necessary using realistic description of fracture length, orientation, connectivity, aperture, spacing, etc. / Paper 3,4 and 5 reprinted with kind persmission of Elsevier Science, Science Direct.

This research project studies the feasibility of developing and applying an integrated field simulator to simulate the production performance of an entire oil or gas field. It integrates the performance of the reservoir, the wells, the chokes, the gathering system, the surface processing facilities and, whenever applicable, gas and water injection systems. The approach adopted for developing the integrated simulator is to couple existing commercial reservoir and process simulators using available linking technologies. The simulators are dynamically linked and customized into a single hybrid application that benefits from the concept of open software architecture. The integrated field simulator is linked to an optimization routine developed based on the genetic algorithm search strategies. This enables optimization of the system at field level, from the reservoir to the process. Modeling the wells and the gathering network is achieved by customizing the process simulator. This study demonstrates that the integrated simulation improves currentcapabilities to simulate the performance of an entire field and optimize its design. This is achieved by evaluating design options including spread and layout of the wells and gathering system, processing alternatives, reservoir development schemes, and production strategies. Effectiveness of the integrated simulator is demonstrated and tested through several field-level case studies that discuss and investigate technical problems relevant to offshore field development. The case studies cover topics such as process optimization, optimum tie-in of satellite wells into existing process facilities, optimal well location, and field layout assessment of a high pressure high temperature deepwater oil field. Case study results confirm the viability of the total field simulator by demonstrating that the field performance simulation and optimal design were obtained in an automated process with reasonable computation time. No significant simplifying assumptions were required to solve the system and tedious manual data transfer between simulators, as conventionally practiced, was avoided.

The planned new railway station in Holmestrand whose location will be inside a basalt plateau poses challenges concerning the grouting and water and frost protection. Based on grouting works in adjacent tunnels Snekkestad and Sj&#248;skogen as well as the entrance tunnels of the station hall, a loosely attempt to predict the grouting sitatuation for the station hall will be made. Pre-construction investigations including CPTU, oedometer, piezometers and ERT tomography have hardly revealed any signs of inflows. The precipiation pattern causes seasonal fluctuations in the groundwater. Hydrologically, the Holmestrand plateau is naturally drained by the existing Holmestrand road tunnel. The Holmestrand plateau consists of column basalt and various soil masses cover its top. There exists a weakness zone that may cause problems for the station hall, meaning that grouting will have to be extensive to maintain the inflow criterion. By the aid of a formula of calculating the expected inflow for the station hall, a strict requirement emerges when comparing this to a standard double-lane railway. Grouting works will take place at an inflow criterion of 5 L/(min/(100 m)) by pre-grouting fans. Should difficult geological conditions occur, control fans, extra fans and post-grouting fans may be applied. Measuring water loss and inflow may happen, both by construction of dams in the tunnel and directly measuring the inflow from boreholes. Alternatives to grouting include concrete lining, etc. Likely water and frost protection solutions are PE foam plates, concrete elements, sprayable membranes such as the BASF masterseal 345, etc. The latter has been tested in a frost laboratory and the Geving&#229;sen tunnel, where the most important conclusions are that the freezing index has no effect of how deep the zero-degree isotherm penetrates into the rock mass and that the temperature pattern is not cumulative. The tunnel results show no significant leakages. Also, the BASF masterseal 345 shows high deformation load capacities.Results from the grouting show highly varying trends according to the difference in geology, both when studying the distribution of grout amounts and the pressure per borehole per grouting fan and the total amounts of grout mass and the average pressure per grouting fan. In areas of the cross-section with low-quality rock the pressure seems to decrease and the amounts of grout mass increase. Also, the inflow criterion does not always control the amounts of injected mass, as the overburden and surface installations, as well as the rock mass and joint system situation play an important role. 3D measurements giving the rock stress distribution may also serve as guidelines for the grouting works, as will the vertical joint situation of the station hall. The water and frost protection solution is likely to be either the PE foam plates or the concrete elements. The author argues that the BASF masterseal 345 shows decent qualities but requires more testing before being applied at such a project.

Som del av nye E6 fra Trondheim til Stj&#248;rdal skal det bygges en ny tunnel fra Nyhavna til Strindheim. Strindheimtunnelen vil ved ferdigstillelse i 2014 best&#229; av to parallelle l&#248;p med tverrsnitt T9,5 og lengde 2,5 km. Ved dagsonen p&#229; Nyhavna (dagsone vest) vil tunnelen ligge som en 300 meter lang betongtunnel i kvikkleire ved nedre M&#248;llenberg f&#248;r den kommer ut i dagen ved Nyhavna. P&#229;grunn av det tettbebygde omr&#229;det og den ustabile kvikkleira er det satt strenge krav til utf&#248;relsen av prosjektet. Dette har gitt en rekke utfordrende ingeni&#248;rgeologiske problemstillinger, som hovedsakelig er rettet mot p&#229;hugget der betongtunnelen g&#229;r inn i berget. Hvert av tunnell&#248;pene vil her ha et tverrsnitt p&#229; 96m2, og kun v&#230;re adskilt av en to meter bred pilar. Overdekning er ned mot tre meter.Sikringen av portalomr&#229;det og tunnelen ved dagsone vest er omfattende, og kan deles inn i fire hoveddeler:&#149;Stagforankring av spuntr&#248;rvegg&#149;Betongdrager og stagforankring over portalen&#149;Generell sikring i tunnelen&#149;Konstruksjon av pilarenGjennom analyser i form av beregninger og numeriske modeller, er det gjort en vurdering av de sikringstiltak som utf&#248;rt. Generelt er sikringstiltakene ved dagsone vest optimale. Den totale sikkerheten er ivaretatt, men analysene viser at det enkelte steder er sm&#229; marginer. Analysemetodene er vurdert til &#229; v&#230;re gode, men som for alle bergmekaniske beregninger og modeller m&#229; det gj&#248;res en rekke forenklinger og antagelser. Dette krever god ingeni&#248;rgeologisk forst&#229;else n&#229;r resultatene skal vurderes. Selv om prosjektet ved dagsone vest er et unikt p&#229; mange m&#229;ter, kan det forventes liknende prosjekter i fremtiden. Spesielt gjelder dette tunneldriving med liten overdekning. P&#229; denne m&#229;ten vil de erfaringer, i form av sikringsmetode og beregningsmetode, som gj&#248;res ved dagsone vest og generelt i Norge v&#230;re nyttig for fremtidige tunnelprosjekter. For alle tunnelprosjekter m&#229; ulike p&#229;huggsplasseringer vurderes. Ofte er det et valg mellom et p&#229;hugg med liten overdekning og liten p&#229;virkning p&#229; omgivelsene, eller et p&#229;hugg med st&#248;rre overdekning der det kreves at det fjernes store mengder masser inn mot p&#229;hugget. Dette er ogs&#229; tilfellet ved dagsone vest. Basert p&#229; kostnadsdata fra dagsone vest, er det gjort en vurdering av de to alternativene. Ved dagsone vest ble det valgt et p&#229;hugg med liten overdekning for &#229; hindre flytting av hus rundt byggegropen. Dette viser seg &#229; v&#230;re det mest kostnadseffektive valget. Hadde det ikke v&#230;rt n&#248;dvendig &#229; fjerne hus, ville den opprinnelige p&#229;huggsplasseringen v&#230;rt den mest kostnadseffektive. Generelt er dette er en problemstilling som m&#229; avgj&#248;res basert p&#229; gjennomf&#248;rbarheten, omgivelsene, kostnadene, tidsforbruk og estetikk.

The 22nd of February 1756 the largest historically recorded rockslide in Norway took place at Tjelle in Langfjorden, M&#248;re &amp; Romsdal County. Three displacement waves of up to 50 meters were created in Langfjorden by the impact of the failed rock mass constituting the Tjellefonna rockslide. A total of 32 people were killed, and 168 houses and 196 boats around the fjord were destroyed.This thesis is continuation of a project assessment carried out in 2011, and comprises a back-analysis of the Tjellefonna rockslide. The ante-rockslide topography (ART) is reconstructed and a detailed volume calculation of the rockslide is carried out using two modern techniques: the Slope Local Base Level (SLBL) and a manual ART reconstruction in the PolyWorks software. The reconstructed pre-rockslide topography is then used in the 2D numerical modelling software Phase2, for a detailed study of the parameters and trigger factors that affected the slope stability. The volume of the deposits (on- and offshore) is calculated to be around 11 million m3, giving an initial volume of the rockslide between 9 to 10 million m3. This is less than the earlier calculations of 12 to 15 million m3, and could have consequences for previous rockslide-generated tsunami modelling (e.g. for the &#197;knes rock slope). The Phase2 analyses include shear strength reduction (SSR) investigations and sensitive parameter tests. It is demonstrated that the failure of the Tjellefonna slope must have required strain softening in combination with triggering factors, where high groundwater is an essential feature. Earthquake, on the other hand, is ruled out as a triggering factor. Additionally, the analyses show that a sub-horizontal structure is critical in order to induce slope instability. This could be represented either by the J5 joint set or an observed sub-horizontal fault, although fieldwork and modelling indicates that the fault is the most important.The sliding surface has been evaluated using the Phase2 and SLBL results. It is concluded that the Tjellefonna rockslide was not composed of a uniform plane, but of a complex surface consisting of joints, faults, foliation and intact rock bridges. Moreover, it is obvious that the Tjellefonna failure was closely related to the tectonic deformation of the rocks in this area. The failure was likely also a consequence of progressive accumulation of rock weakening (strain softening), acting to degrade the equilibrium state of the slope. This could have generated a hillside creep explaining the growing tension cracks observed at the present crown prior to the rockslide.

Today, the larger cities in Norway are linked with railways, but the rail transport system is in need of an upgrade in order to compete with other means of transport. Long journey times associated with the Norwegian railway is one of the main factors contributing to that most people prefer travelling by air when travelling longer distances. Thus, a great potential exists for high-speed railway lines between the major cities of Southern Norway, which will reduce journey times significantly.On February 19, 2010, in a mandate from the Ministry of Transport and Communications, the Norwegian National Rail Administration was asked to study the possibilities of constructing high-speed railway lines in Southern Norway. One of the assessment&apos;s main conclusion is that development costs for the alternative routes are substantial and vary considerably depending on the proportion of tunnels on the respective lines. This is especially relevant for the link between Oslo and Bergen which will have to cross large mountainous areas. With strict requirements regarding inclination and stiffness of alignment, there will be numerous long ($&gt;$ 5 km) to very long ($&gt;$10 km) and partly deep tunnels along this particular route.In addition to large investment cost, challenges related to long and deep tunnels are considerable. Important aspects which needs to be considered are related to construction works, geology, environment and operation. Geology plays an important role since adverse and especially unforseen geological conditions may influence construction time and costs. In Southern Norway, the rock mass mainly consists of crystalline basement rocks of good quality. However, rock mass in faults and weakness zones found within the basement rocks have reduced quality. Cambro-Silurian sedimentary rocks also exist, which generally have lower strength and higher deformability than the basement rocks.This thesis focuses on one long tunnel proposed for the high-speed railway link between Oslo and Bergen. The tunnel will be about 40 km long, has a maximum overburden of 900 m and crosses under the Hardangerj{o}kulen glacier. The thesis evaluates engineering geological conditions of the tunnel and the most crucial aspects of tunnel stability problems are covered. Theoretical aspects of main factors influencing on tunnel stability are evaluated, including water inflow, potential swelling, faults and weakness zones and stress induced problems. Water inflow, tunnel squeezing and spalling are analysed and predicted by analytical and empirical approaches. Numerical modelling is used for analysing brittle failure in the rock mass. Special challenges related to long and deep tunnels are also emphasized. Based on findings in the stability assessment, construction costs and construction time for the tunnel are estimated. This includes estimates for both conventional and TBM tunnelling methods.It is concluded that the tunnel will face different geological challenges such as 1) spalling in massive brittle basement rocks, 2) tunnel squeezing in weak phyllite and 3) considerable water inflow under high pressure in fractured rock and weakness zones, which most likely will influence on the stability during tunnel excavation. Using conventional excavation methods, estimated construction time for one tunnel tube is 9.5 years. On the other hand, using TBM, estimated construction time is 4.9 years. Total costs for both main tunnel tubes are estimated to be 9.9 and 10.7 billion NOK for conventional and TBM excavation methods, respectively.

Rogfast er ein planlagt 26 km undersj&#248;isk to l&#248;ps T12,5 tunnel som skal kryssa Boknafjordenmellom Randaberg og Bokn. Djupaste punkt er p&#229; 390 meter under havet og skal i tillegg haeit toplans kryss med ein T10,5 enkel 4 km tunnel til Kvits&#248;y. Det siste &#229;ret er det gjort eindel unders&#248;kingar for armen opp til Kvits&#248;y. Desse unders&#248;kingane er brukt som grunnlagfor denne oppg&#229;va. Drivetekniske og bergmekaniske parametrar for bergartane som er funneunder kjerneboring er unders&#248;kt. Det er ogs&#229; vurdert sikringsbehov for tunnelen etter StatensVegvesen sine sikringsklassar. Dette er gjort ut fr&#229; seismikk, flyfoto og numeriske analysar.Seismikken som er utf&#248;rt kring Kvits&#248;y, viser ein del svakhetssoner med i hovudsak str&#248;kN-S. Det er oppdaga l&#229;gast seismisk hastighet i Kj&#248;rkjesundet. Dei borhola som er bora nordp&#229; Kr&#229;g&#248;y viser h&#248;g Q-verdi (&gt;10) for subvertikalt hol, 80 grader, medan 30 gradershol viserh&#248;g Q-verdi dei &#248;vste 150 metrane med d&#229;rlegare fjell under (Q-verdi&lt;1). I desse borhola ogtidlegare utf&#248;rte borhol er det utf&#248;rt vasstapsm&#229;lingar som visar tett materiale med lite vasstap.Samanliknar ein Lugeon-verdien med Q-verdien er det ein viss samanheng. Det subvertikaleborholet blei bora for spenningsm&#229;ling som er sv&#230;rt usikre grunna f&#229; m&#229;lingar og lite eignamateriale for testing. Det blei funne spenning ved omlag 77 meter (v=2,9 MPa, h=0,4 MPa,H=1,7 MPa) og 202 meter (v=7-11 MPa, h=2-6 MPa, H=4-8 MPa med antakingar) djup.Utf&#248;rte resistivitetsm&#229;lingar indikerer at fallet til svakhetsoner i omr&#229;det er steilt, eller svaktfall mot aust.Testing av bergmekaniske eigenskapar stadfestar tidlegare utf&#248;rte m&#229;lingar. Bergartane somer testa er gr&#248;nnstein og svartskifer. Dei drivetekniske parametrane til svartskiferen indikerermiddels sprengbarhet (SPR), l&#229;g til h&#248;g borbarhet (DRI), l&#229;g til veldig l&#229;g borslitasje (BWI) ogmedium til h&#248;g levetid p&#229; TBM kuttarar (CLI). Testar p&#229; gr&#248;nnsteinen indikerer god sprengbarhet,middels borbarhet, veldig l&#229;g borslitasje, og veldig h&#248;g til ekstremt h&#248;g CLI.Phase2 er brukt som modelleringsprogram i numerisk analyse. Inngangsparametra er valgtut fr&#229; dei bergmekaniske testane, spenningsm&#229;lingane, i tillegg til samanlikning med tidlegareutf&#248;rte analysar. Det er modellert med gr&#248;nnstein, tre kvalitetar p&#229; svartskifer i tillegg til&#229; sj&#229; p&#229; kryssing av svakhetssoner. Analysen har i hovudsak lagt vekt p&#229; deformasjonar somer oppn&#229;dd med ulike sikringstypar. Gr&#248;nnsteinen og beste kvaliteten p&#229; svartskiferen er dettilstrekkeleg &#229; sikra med spredt bolting, sikringsklasse I. Svartskifer av middels kvalitet b&#248;rspr&#248;ytebetong og systematisk bolting kombinerast (sikringsklasse III). Forbehandling av bergetvil vera ein fordel, men ikkje naudsynt ut i fr&#229; deformasjonar. D&#229;rleg svartskifer og vedkryssing av svakhetssoner b&#248;r forbehandling av berget utf&#248;rast. Dette kan gjerast som injeksjonog forbolting. Analysen viser at det b&#248;r leggast ein del arbeid ned i &#229; f&#229; god injeksjonog forbetring av eigenskapane til berget. Tunnelen b&#248;r anten ha full utst&#248;yping eller boltast im&#248;nster og brukast spr&#248;ytebetongbogar for knusingssona og d&#229;rleg svartskifer. Ein kan ogs&#229;vurdera &#229; st&#248;ypa s&#229;len, men d&#229; b&#248;r han krummast. Ved kryssing av svakhetssone er det end&#229;viktigare &#229; forbehandla berget. Dette for &#229; avlasta sikringa og la fjellet ta opp meir krefter.Analyse av sikringsomfang for tunnelen viser at omlag 55 % av tunnellengda er forventa&#229; koma i sikringsklasse I og II, medan omlag 10 % vil koma i sikringsklasse V og VI. Detb&#248;r fokuserast spesielt kring kryssing av fjordarmane p&#229; Kvits&#248;y, og kjerneboring p&#229; stuff b&#248;rutf&#248;rast for &#229; vita om forbehandling av berget er naudsynt.

I Trondheim bygger Statens vegvesen ny del av E6 Trondheim &#150; Stj&#248;rdal. NCC Construction anlegger en 300 m lang l&#248;smassetunnel med 4 felt. Det er mange utfordringer i denne entreprisen. Grunnen best&#229;r av kvikkleire der utgravingen er dypest, og et tett befolket nabolag best&#229;ende av verneverdige bygninger ligger helt inntil byggegropa. Med bakgrunn i dette er det i kontrakten satt strenge krav til innlekkasje i byggegrop og rystelser. Denne rapporten tar for seg den opprinnelig planlagte og den gjennomf&#248;rte drivemetoden for forskj&#230;ringen og tunnelen. I innledende fase ble wiresaging lansert som metode for berguttaket. Uttaket er imidlertid gjennomf&#248;rt med s&#248;mboring. Med utgangspunkt i funksjonskravene i kontrakten for Dagsone vest ser det ut til at valget av s&#248;mboring har v&#230;rt et fornuftig valg. Dette er fordi kravet om tett byggegrop veier tyngre enn kravet om begrensning av rystelser. Med bruk av s&#248;mboring kunne man bruke s&#248;mhullene til videre injisering der man opplevde innlekkasje. Og per i dag finnes det ingen direkte metode for &#229; bruke et wiresaget sliss som utgangspunkt for injeksjon. Dersom kravet til reduserte rystelser hadde blitt vektlagt tyngst ville wiresaging v&#230;rt en god metode. Men for &#229; oppn&#229; full rystelsesdempende effekt hadde man m&#229;ttet sage konturen f&#248;r sprengning ble utf&#248;rt. Dette hadde f&#248;rt til forsinkelser fordi det hadde tatt lengre tid &#229; skape adkomst til p&#229;hugget dersom man ikke kunne sprengt ut midtpartiet av byggegropa f&#248;r sagingen var gjort. Dessuten m&#229;tte spuntfoten v&#230;rt forankret f&#248;r man kunne begynt &#229; sage. Alts&#229; ville wiresaging skapt st&#248;rre avhengigheter enn man fikk ved bruk av s&#248;mboring. I tillegg til dette underbygges et valg om s&#248;mboring med at wiresaging berammes av en stor sikkerhetssone. I den trange byggegropa p&#229; M&#248;llenberg hadde man raskt f&#229;tt problemer med utf&#248;relsen av samtidige prosesser med et plasskrevende wiresagingsoppsett.Ut i fra geologiske forhold hadde wiresaging v&#230;rt fullt gjennomf&#248;rbart i Dagsone vest. Men hensyn til omgivelser, logistikk og plasshensyn gj&#248;r at s&#248;mboring er &#229; foretrekke.