<p>Exploration for oil and gas is moving towards deeper waters. Steel has been the most common riser material. Related to deep water concepts titanium has become an alternative to steel for these applications.</p><p>Several codes exist today for predicting collapse loads for marine pipes. However, the capacity formulas are developed for steel. If the formulas are applied directly to titanium several parameter uncertainties will be unknown. Ideally, extensive model testing of titanium pipes is required. This thesis discusses and investigates utilisation of experimental material test data and a supplementary numerical approach based on finite element analysis. The relationship between material model parameters as input to the analysis and the collapse capacity is investigated by performing a series of nonlinear FEM analyses.</p><p>Statistical models for the input material model parameters are established based on tests on small specimens cut from titanium pipes. These models are subsequently combined with results from the FEM analyses by application of response surface methods. As output from the analysis, the probability distributions of the pipe capacity with respect to local buckling/collapse are obtained.</p><p>Finally, the data from the nonlinear finite element analyses are compared to a relevant design code. Suggestions for a possible basis for design formulas to check for the local collapse capacity of deep water titanium risers are provided.</p>

<p>This thesis presents an evaluation of statistical methods for modelling pipe failures for each individual pipe in a water distribution network. This thesis introduces the Non Homogeneous Poisson Process (NHPP) with covariates (i.e. explanatory variables) as an appropriate method for modelling pipe failures in water networks. As part of this research, a computer program has been developed that estimates the parameters in the NHPP (“Power law” model). The results from this NHPP model are compared to the results obtained from a modified Weibull Proportional Hazards Model (PHM), where the hazard function is allowed to continue beyond the pipe’s first failure. The models are applied in a case study using data for the water distribution network in Trondheim, Norway.</p><p>The statistical models have been calibrated, verified and used to predict failures for both networks (i.e. group of pipes) and individual pipes. Covariates that have a significant influence on the rate of occurrence of failures (ROCOF) are documented. Based on the results from the case study, NHPP is recommend over the Weibull PHM for modelling failures in water networks.</p><p>The output from the statistical models can be used for a variety of purposes in water network management. In the long term the models can be used to estimate future budget needs for rehabilitation. In the short term the models can be used to define candidates for replacement based on poor structural condition. Information about failure intensity is also required for carrying out network reliability analysis. For this purpose reliability data for each individual pipe is required, which is exactly what the predictive models described in this thesis provide.</p>

<p>The main purpose of the thesis work has been to improve the existing prediction models and to provide a toolbox for the TBM tunnelling industry (project owners, consultants, contractors, manufacturers, etc.) to be used through all phases of a project:</p><p>• Preliminary and feasibility studies</p><p>• Project design and optimisation</p><p>• Site investigations</p><p>• Tendering and contract</p><p>• Construction</p><p>• Possible disputes or claims.</p><p>The various reports of the thesis treat various subjects of TBM tunnelling. Combined with other estimation models published in the Project Report Series from the Department of Building and Construction Engineering, the reports of the thesis provides a reliable and practical tool to be used for:</p><p>• Estimating net penetration rate and cutter life</p><p>• Estimating construction time and costs, including risk or uncertainty</p><p>• Assessing risk with regard to deviation or variation in estimated rock mass boreability, machine parameters and tunnelling performance</p><p>• Designing auxiliary systems such as ventilation, muck transport, etc.</p><p>• Establishing and managing price regulation in contracts</p><p>• Verifying machine performance</p><p>• Back-mapping and verification of the geological conditions</p><p>• Collecting, normalising and analysing of rock samples, machine performance data and cutter wear data.</p><p>The thesis work has not been focused on basic principles, theoretical modelling or laboratory experiments of rock cutting with disc cutters, although observations and results from field studies are presented and analysed in [11]. Several other researchers and institutions have covered those topics. To be mentioned here is the prominent and comprehensive research done at Colorado School of Mines in the USA and at Luleå University of Technology in Sweden. Both institutions have a series of publications ranging over three decades in this area.</p> / This thesis consists of 10 volumes. Only volume one is available for download. See http://www.tunnel.no/ for more information or contact the author: amund.bruland at ntnu.no

<p>The project was made in cooperation with Coffee Queen AB, Arvika. The task was to develop and design a new cooler for the milk to Jura Impressa X9, an espresso machine. The good assistance with staff at Coffee Queen and engineers in China and at KPA in Karlstad led to a solution to the problem. It was a long road to get there, many different concepts was developed. When the day came to decide which concept to work with, the choice stood between two different technical solutions. Alt 1: The classic mini-fridge with today’s technique but a new design. Alt 2: Thermos with external cooling and a design which follows the X9. We choice alt 2 because of the fact that part of the production would fit Coffee Queens factory and therefore would it be possible to keep the costs down. The fact that it is a totally new idea in this business made it even more interesting and easier to make a choice. Both design and function is new, which make it interesting to keep working with. In cooperation with engineers in China there will be made a construction so they can make all necessary tests. This will probably happen autumn 2006. The new technique which the group has come up with is that all technique lays external, in a shell made of polypropen, which make it possible to clean the thermos in the dishwasher. Thermos: Vacuum-shaped in stainless steel with bottom of aluminium, covered with a protected surface, that works like a cold plate. Shell made of pp: shape-molding in polypropen and enclose the coolingsystem. This system are Peltiere, where the cooling is generated, spacer block and heat sink, where the heat are led away, and the fan which takes in cold air and blows out warm. The project has become much larger than Coffee Queen expected from the beginning so they will continue this work even after the students have done their share of the project. The new technique is the big question which requires more tests. These tests will carry through as soon as the group has sent all drafts of design and all info that has been gathered during the project. When the factory in China has made a construction of it they will send it to Coffee Queen and the project-group will be contacted to have a chance to take part of these tests.</p> / <p>Projektet genomfördes i samarbete med Coffee Queen AB i Arvika. Uppgiften bestod i att utveckla och formge en ny förvaring av mjölk till kylning till espressomaskinen Jura Impressa X9. Genom nära samarbete med personalen på Coffee Queen samt ingenjörer i Kina och på KPA i Karlstad togs en lösning fram. Vägen dit var lång. Efter att konceptvalet gjordes stod det mellan två olika tekniska lösningar. Alt 1: Klassiskt minikylskåp med befintlig teknik men ny formgivning. Alt 2: Termos med dockningsstation med kylanordning i och formgivning som följer X9:an. Då delar av tillverkningen skulle passa Coffee Queens fabriker, vilket kan bidra till att hålla kostnaderna relativt låga, valde studenterna alt 2. Att det sedan är en helt ny idé som ännu inte finns i branschen bidrog till att valet underlättades. Både funktionen och designen hade ett nyhetsvärde som var värt att jobba vidare med, enligt Coffee Queen. Under hösten 2006 kommer det att göras tester av en prototyp. Denna prototyp med den nya tekniken kommer att konstrueras av ingenjörer i Kina. Den teknik som studenterna arbetat fram bygger på att all teknik ligger i dockningsstationen och termosen skall vara anpassad för att kunna rengöras i diskmaskin. Termos: Vakuumformad i rostfritt stål med en botten av lackad aluminium. Aluminiumplattan fungerar som en kylplatta och lacken ser till att mjölk och aluminium inte kommer i kontakt med varandra, vilket är ett måste för att uppfylla livsmedelskraven. Dockningsstation: Formsprutas i plast och innesluter kylanläggningen. Denna anläggning innefattar peltiereelement, där själva kylan genereras, kylfläns och kylblock, där värmen leds bort, samt fläkt som suger in kall luft och blåser ut varm. Då projektet visat sig bli mycket större än Coffee Queen från början räknat med, kommer detta att resultera i fortsatt arbete från deras sida. Den del som inte kunnat arbetats igenom är själva kylanordningen, då det är en ny teknik som kräver tester. Dessa tester kommer att genomföras så fort som projektgruppen har lämnat alla formgivningsförslag och det som tagits fram under projektets gång. När en prototyp har tagits fram av ingenjörerna i Kina kommer den att sändas till Coffee Queen för att genomgå tester. När det är dags för dessa tester kommer projektgruppen att kontaktas för att få chansen till att vara med och ta del av dessa.</p>

The background for this thesis is based on the assumption that the success of solar buildings relies on the assessment and integration of all the different design objectives, called criteria. These criteria are often quite complicated to deal with (e.g. environmental loading) and may be conflicting. The different design issues and the many different available energy technologies call for different areas of expertise to be involved in the design of solar buildings. This makes it difficult to evaluate the overall “goodness” of a proposed design solution. Also, the communication between design professionals and the client becomes complicated. The goal of this work was therefore to produce a means for the design team and clients to be able to better understand and handle holistic solar design. A first hypothesis was that a structured approach for evaluating design alternatives might be a means to this end. In order to specify an approach that would fit into the building design process, an analysis of design process theory and building design practice was carried out (chapter 2). Also, special solar design issues were investigated. This analysis resulted in the following conclusions: · Most building design processes start out with no clearly defined goals or criteria of success. The design criteria are refined and discovered through evaluation and feedback on alternative design proposals. · Design involves a lot of subjective value judgements, and decisions are often based on experience, “gut feeling”, or intuition. Design options are evaluated based on quantitative and qualitative performance measures. There exists no objective optimal design solution. · It is possible to identify some main activities that are common to most design processes. These are categorized into 4 main tasks: problem formulation, generation of alternatives, performance prediction and evaluation. The activities are very much overlapping and dependent on each other. · Decision-making in design happens mainly through evaluation of proposed design solutions.

Exploration for oil and gas is moving towards deeper waters. Steel has been the most common riser material. Related to deep water concepts titanium has become an alternative to steel for these applications. Several codes exist today for predicting collapse loads for marine pipes. However, the capacity formulas are developed for steel. If the formulas are applied directly to titanium several parameter uncertainties will be unknown. Ideally, extensive model testing of titanium pipes is required. This thesis discusses and investigates utilisation of experimental material test data and a supplementary numerical approach based on finite element analysis. The relationship between material model parameters as input to the analysis and the collapse capacity is investigated by performing a series of nonlinear FEM analyses. Statistical models for the input material model parameters are established based on tests on small specimens cut from titanium pipes. These models are subsequently combined with results from the FEM analyses by application of response surface methods. As output from the analysis, the probability distributions of the pipe capacity with respect to local buckling/collapse are obtained. Finally, the data from the nonlinear finite element analyses are compared to a relevant design code. Suggestions for a possible basis for design formulas to check for the local collapse capacity of deep water titanium risers are provided.

This thesis presents an evaluation of statistical methods for modelling pipe failures for each individual pipe in a water distribution network. This thesis introduces the Non Homogeneous Poisson Process (NHPP) with covariates (i.e. explanatory variables) as an appropriate method for modelling pipe failures in water networks. As part of this research, a computer program has been developed that estimates the parameters in the NHPP (“Power law” model). The results from this NHPP model are compared to the results obtained from a modified Weibull Proportional Hazards Model (PHM), where the hazard function is allowed to continue beyond the pipe’s first failure. The models are applied in a case study using data for the water distribution network in Trondheim, Norway. The statistical models have been calibrated, verified and used to predict failures for both networks (i.e. group of pipes) and individual pipes. Covariates that have a significant influence on the rate of occurrence of failures (ROCOF) are documented. Based on the results from the case study, NHPP is recommend over the Weibull PHM for modelling failures in water networks. The output from the statistical models can be used for a variety of purposes in water network management. In the long term the models can be used to estimate future budget needs for rehabilitation. In the short term the models can be used to define candidates for replacement based on poor structural condition. Information about failure intensity is also required for carrying out network reliability analysis. For this purpose reliability data for each individual pipe is required, which is exactly what the predictive models described in this thesis provide.

The main purpose of the thesis work has been to improve the existing prediction models and to provide a toolbox for the TBM tunnelling industry (project owners, consultants, contractors, manufacturers, etc.) to be used through all phases of a project: • Preliminary and feasibility studies • Project design and optimisation • Site investigations • Tendering and contract • Construction • Possible disputes or claims. The various reports of the thesis treat various subjects of TBM tunnelling. Combined with other estimation models published in the Project Report Series from the Department of Building and Construction Engineering, the reports of the thesis provides a reliable and practical tool to be used for: • Estimating net penetration rate and cutter life • Estimating construction time and costs, including risk or uncertainty • Assessing risk with regard to deviation or variation in estimated rock mass boreability, machine parameters and tunnelling performance • Designing auxiliary systems such as ventilation, muck transport, etc. • Establishing and managing price regulation in contracts • Verifying machine performance • Back-mapping and verification of the geological conditions • Collecting, normalising and analysing of rock samples, machine performance data and cutter wear data. The thesis work has not been focused on basic principles, theoretical modelling or laboratory experiments of rock cutting with disc cutters, although observations and results from field studies are presented and analysed in [11]. Several other researchers and institutions have covered those topics. To be mentioned here is the prominent and comprehensive research done at Colorado School of Mines in the USA and at Luleå University of Technology in Sweden. Both institutions have a series of publications ranging over three decades in this area. / This thesis consists of 10 volumes. Only volume one is available for download. See http://www.tunnel.no/ for more information or contact the author: amund.bruland at ntnu.no

In this investigation strength and structural behaviour of prestressed concrete is studied with one full scale test of one flat slab, 16000 mm x 19000 mm, and three slabs on ground each 4000 mm x 4000 mm with thickness 150 mm. The flat slab was constructed and tested in Aalesund. This slab has nine circular columns as support, each with diameter 450 mm. Thickness of this test slab was 230 mm and there were two spans in each direction, 2 x 9000 mm in x-direction and 2 x 7500 mm in y-direction from centre to centre column. The slab was reinforced with twenty tendons in the middle column strip in y-direction and eight tendons in both outer column strips. In x-direction tendons were distributed with 340 mm distance. There were also ordinary reinforcement bars in the slab. Strain gauges were welded to this reinforcement, which together with the deflection measurements gives a good indication of deformation and strains in the structure. At a live load of 6.5 kN/m2 shear failure around the central column occurred: The shear capacity calculated after NS 3473 and EuroCode2 was passed with 58 and 69 %, respectively. Time dependent and non-linear FE analyses were performed with the program system DIANA. Although calculated and measured results partly agree well, the test show that this type of structure is complicated to analyse by non-linear FEM. Prestressed slabs on ground have no tradition in Norway. In this test one reinforced and two prestressed slabs on ground were tested and compared to give a basis for a better solution for slabs on ground. This test was done in the laboratory at Norwegian University of Science and Technology in Trondheim. The first slab is reinforced with 8 mm bars in both directions distributed at a distance of 150 mm in top and bottom. Slab two and three are prestressed with 100 mm2 tendons located in the middle of slab thickness, and distributed at a distance of 630 mm in slab two and 930 mm in slab three. Strain gauges were glued to the reinforcement in slab one and at top and bottom surface of all three slabs. In slab two and three there were four load cells on the tendons. Each slab were loaded with three different load cases, in the centre of slab, at the edge and finally in the corner. This test shows that stiffness of sub-base is one of the most important parameters when calculating slabs on ground. Deflection and crack load level depends of this parameter. Since the finish of slabs on ground is important, it can be more interesting to find the load level when cracks start, than deflection for the slab. It is shown in this test that crack load level was higher in prestressed slabs than in reinforced slab. There was no crack in the top surface with load in the centre, but strain gauges in the bottom surface indicate that crack starts at a load of 28 kN in the reinforced slab, and 45 kN in the prestressed slabs. Load at the edge give a crack load of 30 kN in reinforced slab, 45 kN and 60 kN in prestressed slabs. The last load case gives crack load of 30 kN in reinforced slab, 107 kN and 75 kN in prestressed slabs. As for the flat slab, FE analyses were performed for all of the three slabs on ground, and analyses shows that a good understanding of parameters like stiffness of sub-base and tension softening model, is needed for correct result of the analyses.

The thesis deals with experimental and numerical modelling to characterize early age tensile and compressive creep and its associated stress relaxation - which are very important properties in stress simulation of early age concrete. For this purpose a comprehensive work was carried out involving construction of a new tensile creep test equipment and development of test procedures to generate basic experimental data. The experimental program is subdivided into four series. Each of the series involves one varying parameter, which is relevant to the time-dependent behaviour of early age HPC. Most of the tests are repeated to check the reproducibility of the test results. The reproducibility of the test results for the BASE concretes confirmed that the experimental setup is reliable, and that it can be used to determine tensile creep of concrete at early ages. An extensive test program has been performed on HPC, with w/b = 0.40. The primary parameters studied were concrete ages at loading (1, 2, 3, 4, 6 and 8 days), stress/strength levels (20-80%), and temperature levels (20, 34, 40, 57 and 60 oC) in addition to the effect of silica fume (0-15%) on tensile creep. The testing apparatus was new and significant efforts were devoted to develop reliable procedures in terms of accuracy and reproducibility. In parallel, compressive creep tests were conducted on a separate testing apparatus, and the results are compared to tensile creep behaviour. It was found that the instantaneous deformation under tension is smaller than under compression, and that the corresponding creep curves also are different. Creep in tension is found to be lower initially, but an almost linear rate is soon established which is much higher than in compression. The consequence is greater creep magnitude and thus greater creep coefficient in tension than in compression. The tests on non-linearity showed that the proportionality limit between stress and sealed tensile creep strain is about 60% of the strength. Creep tests under isothermal temperatures showed that, as for compressive creep, the sealed tensile creep accelerates for temperatures higher than 20 oC. In addition, the maturity principle describes this effect reasonably well, for the tested loading ages of about 3 days. The relatively large amount of experimental data, available in this study, has been used to investigate mathematical models. Comprehensive test results from the TSTM apparatus are analyzed with respect to creep and relaxation, where the effect of temperature on creep and relaxation is emphasized. Simulations of self-induced stresses are performed using the creep model denoted the Double Power Law (DPL). As solution method, the theory of linear viscoelasticity with aging is used. The model (M-DPL) is modified to take into account the effect of irrecoverable creep. For increasing temperatures during the hardening phase, the transient creep, which takes place during heating is taken into account by an additional creep term. Its contribution to stress relaxation was found to be up to 10%. This transient creep term is considered to be irrecoverable during the subsequent temperature decrease. The modified model captures the various characteristics of sealed creep and describes the tensile behaviour at early ages more accurately than the original Double Power Law. The effect of relaxation is found to be relatively large and significant in development of selfinduced stresses. Under isothermal temperature of 20 oC, the relaxation increases to about 40% of the fictive elastic stresses after 3 days and remains about constant after that. On the other hand, presentation of relaxation under realistic temperature histories is much more complicated, because the stresses change from compression to tension. This might also lead to increased tensile stresses because compressive creep reduces compressive stresses, but increases the subsequent tensile stresses. Underestimation of creep in this early period will lead to underestimation of the cracking risk. Creep development at very early ages has an important effect in determination of the creep model parameters. After an evaluation of the test results using six loading ages (1, 2, 3, 4, 6 and 8 days) it was concluded that an optimal test program should include at least 3 loading ages, in which the loading ages 1 and 2 must be included. Furthermore, the test results indicate that partial replacement of cement with silica fume (5-15%) increases the sealed tensile creep. However, the reference concrete without silica fume dose not fit to this systematic pattern.