Construction is often defined as a project-oriented industry that develops complex one-of-a-kind products using an engineer-to-order (ETO) design process. The technical solutions that are developed in specific projects often have integral product architectures that are difficult to re-use in continuous improvement processes. The ETO process also means that very few components can be produced before being ordered, which is necessary for creating economies of scale in production. In contrast, Modify-To-Order (MTO) Configure-To-Order (CTO) or Select variant-To-Order (STO) design processes based on theories of mass customization reuse technical solutions from earlier projects to varying degrees. However, many researchers argue that results and theories from the manufacturing industry cannot be used in the contexts of construction because each construction project has different functional requirements and local site conditions whose interaction mandates the creation of unique end products that cannot be modularized as is done in manufacturing industries. The purpose of this thesis was to investigate how mass customization principles could be utilized in the design of construction products, especially how the adoption of platform architectures and configurators could support the reuse of technical solutions between projects. Several case studies of projects using different specification levels (MTO, CTO and STO) were conducted to test theories of mass customization in the context of construction. The results obtained show that when working at the MTO and CTO specification levels, platform architectures should be based on modules that can be developed incrementally. STO products can be developed with integral product architectures, but if the needs of customers in the target market segment change this presents a risk of ad-hoc end product customization that will adversely affect the production system downstream in the value chain. For all studied specification levels, it is important to determine whether the target market volume is sufficient to justify the cost of developing a product platform. The introduction of design modules in modular platform architectures enables the development and use of configurators in ETO construction design processes. Such tools allow MTO platforms to be customized using a mixture of traditional ETO design and the configuration of predefined modules. Configuration tools for module customization at the MTO and CTO levels must therefore be integrated with the traditional design tools used in construction. The configuration of modular platform architectures also facilitates the effective use of information and its transfer between domains. As the use of pre-defined modules in the product specification process increases, the need to involve multiple design disciplines decreases. At the STO level, the design work can be reduced to such an extent that customization can be achieved using web-based configurators.Overall, the results presented in this thesis indicate that the Products in Product mass customization concept introduced by Erixon (1998) can be implemented at multiple specification levels in the traditional design of construction products. By introducing the new design module category into the platform architecture, predefined construction product platforms can be integrated with the traditional ETO design process and developed incrementally. / Construction is often defined as a project oriented industry developing complex one-of-a-kind products in an engineer-to-order (ETO) driven process by temporary organizations. That is resulting in a fragmented design process with loose connection between different disciplines. Many studies indicate that the early stages of product development is critical for product constructability, but technical solutions that are developed in specific projects lead to integral product architectures that are difficult to re-use in a continuous improvement process. The ETO process also means that very few components can be produced before ordering, a prerequisite for creating economies of scale in production. By changing the product realization process to "modify- to-Order" (MTO), "configure- to-order" (CTO) or "select variant" (STP), which is based on the theories of mass customization, technical solutions can be reused between the specific projects. However, several researchers in the construction industry proclaim that the contexts of construction industry cannot be compared with other industries and products. The variation of interacting functional requirements creates unique end products that cannot be separated in similar way as in the manufacturing industry. Arguments are based on the uniqueness of the end products that is analysed with regards to the highest level in the product architecture, which is why a more nuanced view is required.Mass Customisation can be described as an approach to combine economies of scale from mass production with increased customization for the end customer. To successfully achieve this, the generic product architecture need to be based on a modular architecture with clear separation between functional requirements (FR) and design parameters ( DP) and well-specified interfaces between the modules. Selected market segment affects the demand for product customization relatively the order point and thus affects its product realization process; MTO, CTO and STP, whereupon the selected specification level also affects the generic product architecture with its product platform and how the customization can be done. The purpose of this thesis is to describe whether and how mass customization can be used in the construction industry by describing the relationships between product architectures and the specification levels.Several case studies in the specification levels MTO, CTO and STP have been made based on theory of mass customization. The case studies have been performed in a deductive approach where theories have been tested in real cases and validated through experiments. Results from the cases have improved the understanding in this area and been used in following case studies, why the thesis as a whole can be described as abduction.Research results shows that in the MTO and CTO specification level, product platforms should be based on modules that can be developed incrementally. STP products can be developed with integral product architecture, but if changes in the customer segment occur there is great risk that production will be affected negatively. In all studied specification levels, it is important to understand the market segment volumes to justify the development costs. Introduction of "Design variant module" for modular systems means that configurators for subsystems can be developed. Customization of MTO platforms then consists of a mixture of traditional design and configuration of modules. But to accomplish this, the link between ICT tools in the MTO and CTO process needs to be connected with traditional ICT tools in the construction industry. However, using modular product architectures in the design greatly reduce the information exchange between disciplines. If STP products are developed customization can be done using a web interface.In conclusion, if using the "Products in Product" concept (Erixon, 1998) it is possible to implement theories from mass customization in construction. It is also seen that modular product architecture creates opportunities to repair information chains and minimizes the exchange of information between different disciplines, enabling the use of ICT tools developed in other industries. By introducing a new module category to the existing theory, namely "Design variant module", the traditional design process (ETO) can be coupled with predefined product platforms and develop incrementally. / Godkänd; 2014; 20140416 (patjen); Nedanstående person kommer att disputera för avläggande av teknologie doktorsexamen. Namn: Patrik Jensen Ämne: Byggproduktion/Construction Engineering Avhandling: Configuration of Platform Architectures in Construction Opponent: Professor Lars Hvam, Department of Management Engineering, Technical University of Denmark, Lyngby, Denmark Ordförande: Professor Thomas Olofsson, Avd för byggkonstruktion- och produktion, Institutionen för samhällsbyggnad och naturresurser, Luleå tekniska universitet Tid: Tisdag den 17 juni 2014, kl 13.00 Plats: F1031, Luleå tekniska universitet

Value and waste are concepts that are used in improvement projects. In lean the concepts are fairly simple. Reduce the waste and the value has increased. However, value is both multidimensional and differs over time. If the concepts value and waste are to be used, the concepts must be clearly defined and measured. Otherwise, value can be reduced for the customer/user and the cost increased for the producer/seller. The purpose in this thesis is to investigate how value and waste are perceived by different stakeholders, how value and waste are related, and how value and waste are measured. The focus of the study is the improvement of production and services. The study does not investigate the product/service development. The conclusions are based on a number of cases and research from different fields such as resource-based view and marketing. The study use mix of qualitative and quantitative methods. Measures of forecasting accuracy and their relations where explored with different statistical tools in order to understand the influence of measures and dimensions. The view of value concerning energy efficiency was examined in a statistical analysis of a survey concerning stakeholders’ view of a specific value, energy efficiency, as well as their influence on the value creation process. A multiple qualitative case study explores the relation between value and waste in different settings and the consequences of waste focus. The findings in the multiple case study are confirmed and elaborated further by an additional case study, both qualitative and quantitative, of value stream mapping.Value and waste are analysed with the use of order winners and qualifiers. Also, a model to clarify the consequences of mixing value creation and value exchange for customer/user and producer/seller have been defined and used in the analysis.Depending on the stakeholder there is a difference between whether value can be regarded as a use value, exchange value or both. Even if exchange value is related to a specific moment in time, use value is not. The view of value differs among stakeholders which increase the risk of sub-optimisation in production.Value and waste have multi-dimensional properties and there are links between the different dimensions. The relationships depend upon the situation in question. The lean seven types of waste are not independent dimensions. Also, the concept of waste as anti-value is too simplistic. In all cases studied the focus is on waste, not value. Also, it is often the symptoms of waste that are of interest in measures taken not the root causes. Reduction of waste without considering the value can create new waste. Since waste is a dependent variable, it should not be measured without considering value. Another complication is that value and waste often occurs at different points in time and in different settings.Single measures are sensitive to its environment. Several measures are more robust. Measures distort and influence the perception and thereby the decision of the studied phenomena. Also, the notion of value and waste becomes harder to define and trace as the resolution and detailing of the studied process increases. / Godkänd; 2016; 20151028 (petwal); Nedanstående person kommer att disputera för avläggande av teknologie doktorsexamen. Namn: Peter Wallström Ämne: Byggproduktion /Construction Engineering and Management Avhandling: On Value and Waste Opponent: Docent Kristian Widén, Avd för Byggproduktion, Institutionen för Byggvetenskaper, Lunds tekniska högskola, Lund. Ordförande: Professor Ove Lagerqvist, Avd för byggkonstruktion och -produktion, Institutionen för samhällsbyggnad och naturresurser, Luleå tekniska universitet, Luleå. Tid: Onsdag 14 september, 2016 kl 13.00 Plats: F1031, Luleå tekniska universitet

<p> </p><p>The aim of this Master Thesis is to assess the load carrying capacity of the Glomman Bridge outside of the Swedish city Örebro. The Glomman Bridge is an unreinforced concrete single span arch bridge with backfill. The bridge was constructed in 1923 on assignment from the Swedish National Railways (SJ).</p><p>The failure criteria used in this thesis is that the bridge collapses when any cross section in the concrete arch reaches its ultimate capacity. In reality, the bridge may manage heavier loads than this. When the capacity is reached in a cross section, a hinge is formed and the arch relocates the forces to other parts of the arch that can carry higher stresses. The real bridge will not collapse until a fourth hinge is formed, and by that a mechanism. To be able to calculate the cross section forces in the arch, it was necessary to know the influences of the loads on the arch when they were run along the bridge. For this purpose, influence lines were obtained from a 2D finite element model created in ABAQUS, a general FE-analyses software. A calculation routine to find the least favourable load combination was then created in Matlab, a numerical calculation software. The routine was made to find the worst case among different load cases and to combine the standardized axle pressures with the present number of axles.</p><p>A parametric survey was also performed because the material properties for the different parts of the bridge are very uncertain. In the survey, the initial values were changed one at a time to study the outcome on the load factor. The load factor is the ratio between the ultimate limit load and the actual load. The studied parameters are the compressive strength, the Young's modulus, the density and the Poisson's ratio of the different parts of the bridge. The parameters are studied individually irrespective of possible correlation. The studied parts of the bridge are the backfill, the arch, the abutments and the asphalt. The clearly most important component is found to be the backfill. With increased stiffness or increased Poisson's ratio in the backfill follows increased load factor.</p><p>The equations behind the failure envelope can be derived from equilibrium equations for the unreinforced cross section. The influence lines are normalised with respect to the capacity of the cross section to get the degree of efficiency along the whole length of the arch, instead of the common influence lines that give the cross section forces. This is done because the failure is not caused by large cross section forces but by an exceeded ultimate stress. As the different loads are run along the bridge, the largest positive and negative efficiency for bending moment and normal force are localised. The normalised cross section forces are plotted together with the failure envelope and the load factor is then calculated.</p><p>Several masonry arch bridges were loaded until collapse in a study performed by the British Transport and Road Research Laboratory. One of the bridges in the study, the Prestwood Bridge, has been used in this thesis as a comparison to the Glomman Bridge. The load carrying capacity of the Prestwood Bridge is known, and is used to verify that the method using the failure envelope is applicable.</p><p>To compare the results from the cross section analysis from the failure envelope model to another method, the Glomman Bridge and the Prestwood Bridge were also tested in the commercial software RING 2.0. The method used in RING 2.0 differs from the failure mode in this thesis by calculating the load factor when four different cross sections reach their capacity and the bridge collapses.</p><p>The failure envelope method allows an A/B-value (Axle- and Bogie load) of 102 kN/147 kN when using very poor values of the parameters and 181 kN/226 kN when using a reference case with normal parameters.</p><p>Although the load capacity is found to be acceptable, the uncertainties are still large. To get a more accurate apprehension of the condition of the actual bridge, further research should be carried out, such as e.g. a non-linear model.</p> / <p>Syftet med föreliggande examensarbete är att uppskatta bärförmågan hos bron Glomman utanför Örebro. Glomman är en oarmerad betongvalvbro i ett spann med ovanliggande jordfyllning. Bron byggdes 1926 på uppdrag av Statens Järnvägar (SJ).</p><p>Brottkriteriet i detta examensarbete är att bron går till brott när något tvärsnitt i betongbågen uppnår sin kapacitet. I själva verket är det möjligt att bron kan klara tyngre last än detta. När kapaciteten nås i ett tvärsnitt uppstår en led och bågen omlagrar krafterna till andra bågdelar som klarar större spänningar. Den verkliga bron rasar inte förrän en fjärde led har utvecklats, och därmed en mekanism. För att kunna beräkna tvärsnittskrafterna i bågen, var det nödvändigt att känna till trafiklasternas påverkan på bågen när de kördes över bron. För detta ändamål erhölls influenslinjer från en tvådimensionell finita elementmodell skapad i ABAQUS, ett generellt FE-program. En beräkningsrutin för att finna värsta tänkbara lastkombinering skapades i Matlab, ett numeriskt beräkningsprogram. Rutinen utformades för att hitta värsta fallet bland olika lastfall samt för att kombinera standardiserade axeltryck med det aktuella antalet axlar.</p><p>En parameterstudie utfördes också då materialegenskaperna för de olika delarna i bron är mycket osäkra. I parameterstudien ändrades ingångsvärdena ett åt gången för att studera utslaget på lastfaktorn. Lastfaktorn är förhållandet mellan brottgränslasten och den verkliga lasten. De parametrar som studeras är tryckhållfastheten, <em>E</em>-modulen, densiteten och tvärkontraktionen för de olika brodelarna. Parametrarna studeras enskilt utan hänsyn till eventuell korrelation. De brodelar som studeras är fyllningen, bågen, fundamenten och asfalten. Den klart viktigaste komponenten visar sig vara fyllningen. Med ökad styvhet eller ökad tvärkontraktion i fyllningen följer ökad last­faktor.</p><p>Ekvationerna bakom brottenveloppet kan härledas ur jämviktsekvationer för det oarmerade tvärsnittet. Influenslinjerna normeras med avseende på tvärsnittets kapa­citet för att få ut utnyttjandegraden längs hela bågen. Detta görs då det egentligen inte är för stor tvärsnittskraft som orsakar brott utan för stor spänning. Högsta och lägsta utnyttjandegrad för böjande moment och normalkraft lokaliseras när de olika typlasterna körs över bron. Utnyttjandegraderna placeras i brottenveloppet för att sedan räkna fram en lastfaktor.</p><p>Ett flertal liknande broar har lastats till brott i en studie genomförd av British Transport and Road Research Laboratory. En av broarna i studien, Prestwood Bridge, har använts i denna rapport som jämförelse med Glomman. Då bärförmågan hos Prestwood Bridge är känd används den till att bekräfta att metoden med brott­enveloppet är tillämpbar.</p><p>För att jämföra resultaten från tvärsnittsanalysen i brottenveloppmetoden med en annan metod, testades även Glomman och Prestwood Bridge i det kommersiella programmet RING 2.0. Metoden som används i RING 2.0 skiljer sig från brottmoden i denna rapport genom att istället beräkna lastfaktorn när fyra olika tvärsnitt har uppnått sina kapaciteter och bron kollapsar.</p><p>Metoden med brottenvelopp tillåter ett A/B-värde (Axel- och Boggitryck) på 102 kN/147 kN när mycket dåliga parametervärden används och 181 kN/226 kN när referensfallet med normala parametervärden används.</p><p>Även om bärförmågan kan anses vara acceptabel är osäkerheterna stora. För att få en nogrannare uppfattning om brons faktiska tillstånd bör fortsatta studier utföras, som t.ex. en icke-linjär modell.</p>

<p>The sales of Ground Source Heat Pumps in Sweden and many other countries are having a rapid growth in the last decade. Today, there are approximately 360 000 systems installed in Sweden, with a growing rate of about 30 000 installations per year. The most common way to exchange heat with the bedrock in ground source heat pump applications is circulating a secondary fluid through a Borehole Heat Exchanger (BHE), a closed loop in a vertical borehole. The fluid transports the heat from the ground to a certain heating and/or cooling application. A fluid with one degree higher or lower temperature coming out from the borehole may represent a 2-3% change in the COP of a heat pump system. It is therefore of great relevance to design cost effective and easy to install borehole heat exchangers. U-pipe BHEs consisting of two equal cylindrical pipes connected together at the borehole bottom have dominated the market for several years in spite of their relatively poor thermal performance and, still, there exist many uncertainties about how to optimize them. Although more efficient BHEs have been discussed for many years, the introduction of new designs has been practically lacking. However, the interest for innovation within this field is increasing nowadays and more effective methods for injecting or extracting heat into/from the ground (better BHEs) with smaller temperature differences between the heat secondary fluid and the surrounding bedrock must be suggested for introduction into the market.</p><p>This report presents the analysis of several groundwater filled borehole heat exchangers, including standard and alternative U-pipe configurations (e.g. with spacers, grooves), as well as two coaxial designs. The study embraces measurements of borehole deviation, ground water flow, undisturbed ground temperature profile, secondary fluid and groundwater temperature variations in time, theoretical analyses with a FEM software, Distributed Thermal Response Test (DTRT), and pressure drop. Significant attention is devoted to distributed temperature measurements using optic fiber cables along the BHEs during heat extraction and heat injection from and to the ground.</p> / QC 20100517 / EFFSYS2 / Efficient Use of Energy Wells for Heat Pumps

This dissertation develops, presents and tests a new international tool, the so-called Road Safety Development Index (RSDI), which indicates in a comprehensive and easy way the severity of the road safety situation in a specific country and/or in comparison with other countries. There are three pillars of outcomes involved in the framework of RSDI. One pillar is the People focus (road user behaviour). The second is the System focus (safer vehicles, safer roads, enforcement, management, etc). The third is the Product focus in terms of accident death rates. This thesis analyses each of these pillars. In addition, RSDI links the key national practices of road safety to each other and to the end-results (accident death rates). The study suggests a master-list of performance indicators to be implemented for assessing road safety level in a country and for RSDI building. Based on the “master-list”, a short key list of performance indicators is chosen and classified into two primary categories that correspond to two groups of countries: LMCs “Less Motorised Countries” and HMCs “Highly Motorised Countries”. RSDI aggregates the key performance indicators into one single quantitative value (composite index). Four main objective and subjective approaches are used to calculate RSDI and determine which one is the best. One approach uses equal weights for all indicators and countries, whereas the other approaches give different weights depending on the importance of indicators. Two empirical studies were carried out, in different parts of the world, to determine the applicability of this tool in real world applications. The first empirical study comes from eight European countries (HMCs). The second empirical study comes from five Southeast Asian countries (LMCs). The RSDI results from this study indicate a remarkable difference between the selected countries even at the same level of motorisation and/or with close accident death rates. The unavailability of comparable and useful data are problems for deeper analysis of RSDI, especially the index should be as relevant as possible for different parts of the world. The empirical and theoretical assessments prove that RSDI can give a broader picture of the whole road safety situation in a country compared to the traditional models and can offer a simple and easily understandable tool to national policy makers and public. / Denna avhandling utvecklar, presenterar och testar ett nytt internationellt verktyg, det så kallade Road Safety Development Index (RSDI), vilket på ett begripligt och lättillgängligt sätt beskriver trafiksäkerhetsläget i ett visst land jämfört med andra länder. Resultatet av RSDI utgörs av tre grundpelare. Den första pelaren är Fokus på människor (vägtrafikbeteende). Den andra är Fokus på systemet (säkrare fordon, säkrare vägar, beivrande, management, osv). Den tredje pelaren är Fokus på produkten med avseende på antal döda per fordon och per invånare. Arbetet analyserar var och en av dessa tre pelare. RSDI kopplar dessutom samman de viktigaste nationella praxisarna och erfarenheterna med varandra och till slutresultaten (antal dödsfall). Studien föreslår en lista med de viktigaste indikatorerna på hur olika länder vidtar åtgärder för trafiksäkerheten. Grundat på denna “master-lista” kan en kort lista med de viktigaste indikatorerna skapas och klassificeras i två huvudkategorier för två typer av länder: LMC “länder med låg andel fordon” och HMC “länder med hög andel fordon”. RSDI aggregerar de viktigaste performance-indikatorerna till ett enda kvantitativt mått (ett sammansatt index). Fyra olika objektiva och subjektiva huvudangreppssätt används för att beräkna RSDI och bestämma vilket av dem som är det bästa. En metod använder sig av lika stora vikter för alla indikatorer och länder, medan en annan metod ger olika vikter beroende på indikatorernas betydelse. Två empiriska studier genomfördes i olika delar av världen för att bestämma tillämpligheten av detta verktyg i verkliga situationer. Den första empiriska studien kommer från åtta länder i Europa (HMC-länder). Den andra empiriska studien har gjorts i fem länder i Sydostasien (LMC-länder). Resultaten från detta RSDI tyder på en anmärkningsvärd skillnad mellan de valda länderna, också om andelen bilägare och/eller andra variabler för trafiksäkerhet hålls konstanta. Bristen på jämförbara och användbara data medför problem vid en djupare analys av RSDI för olika delar av världen. De empiriska och teoretiska skattningarna visar att RSDI kan ge en bredare bild av hela trafiksäkerhetssituationen i ett land jämfört med traditionella modeller och kan erbjuda ett enkelt och lättförståeligt verktyg för de nationella beslutsfattarna liksom för allmänheten.

Hydrophobic impregnations often referred to as water repellent agents, today mainly consisting of alkylalkoxysilanes, are often used on concrete to prolong the service life of the structure. This is accomplished by protecting the reinforcement bars from chlorides or by changing the moisture content inside. When the concrete is treated with a water repellent agent the properties of the surface layer becomes hydrophobic and thereby water droplets are stopped from entering, still allowing water vapour to pass through. This change can reduce chloride ingress and stop heavy rain from penetrating through the surface layer. This thesis presents results concerning how the properties of concrete are affected by a hydrophobic impregnation. Moisture transport and fixation in the surface layer of the concrete are studied as well as the secondary effects of more practical use such as the effect on chloride ingress, water absorption and humidity level. It also presents results on how the penetration depth and concentration of the water repellent agent (i) depend on a number of parameters, and (ii) affect the outcome of the treatment. Water repellent treatments on a number of different concrete structures in Stockholm, ranging from tunnel to high-rice building, are evaluated as well. The three most important factors for the penetration of any water repellent agent into concrete are time, porosity and degree of saturation. A semi-empirical equation is derived that gives an idea on how much these factors affect the efficient penetration depth of the water repellent agent. The depth and concentration have a major effect on the performance of the treatment. The moisture diffusion coefficient for a water repellent treated concrete is close to constant and not nearly as dependent on the relative humidity (RH) as for untreated concrete. Unlike untreated concrete, where capillary suction plays an important role for the moisture transport at high RH, the vapour transport is the dominant transport mechanism even at high RH for water repellent treated concrete. The moisture fixation is affected by a water repellent treatment and the effect is clearest at high moisture levels. The main reason for this is that the capillary porosity is affected by the treatment to a relatively high degree while the gel porosity to a large extent remains unaffected. A hypothesis is presented which suggests that the RH inside the concrete at the time of the treatment affects not only the depth and concentration but also in which range of pore radii the water repellent agent is present and active. The durability of hydrophobic impregnations can be divided into surface effects and in depth effects. The first is sensitive to the environmental and mechanical loadings and normally disappears within a year while the later can be long lasting if a sufficient depth is reached. Hydrophobic impregnations are not the answer to all problems in concrete related to moisture, but if correctly used it can prolong the service life of the structure which will lead to savings of natural resources and thus both economical and environmental savings for the community. / Vattenavvisande impregneringsmedel, som i dagsläget till största del består av alkylalkoxysilaner, används ofta på betong för att förlänga livslängden på konstruktionen. Detta syfte uppnås genom att armeringen skyddas mot klorider eller att fukthalten inuti betongen sänks. När betongen impregneras ändras ytskiktets fuktmekaniska egenskaper från hydrofila till hydrofoba vilket gör att vattendroppar kan stoppas medan vattenånga tillåts passera. Dessa förändrade egenskaper kan medföra att kloridinträngningen minskar och att kraftiga regn inte tränger genom det impregnerade skiktet. Denna avhandling presenterar resultat om hur betongen påverkas av en vattenavvisande impregnering. Fukttransport och fuktfixering i betongens ytskikt har undersökts men även sekundära effekter som kloridinträngning, vattenabsorption och förändring i fuktinnehåll vilka alla är av större praktisk nytta. Avhandlingen presenterar också resultat om vilka faktorer som påverkar impregneringens inträngningsdjup och koncentration samt vilken betydelse dessa har för funktionen. För att utvärdera impregneringars effekt i olika miljöer har ett stort antal objekt i Stockholm undersökts, innefattande olika konstruktioner från en tunnel till höghus. Impregneringens inträngningsdjup och koncentration har en avgörande betydelse för dess funktion. De tre viktigaste faktorerna för alla impregneringsmedels inträngning i betong är tid, porositet och fuktnivå. En semiempirisk ekvation har tagits fram där det framgår hur dessa tre faktorer påverkar det slutliga inträngningsdjupet för impregneringen. Till skillnad från obehandlad betong är transportkoefficienten för en impregnerad betong nästan oberoende av den relativa fuktigheten (RF) i omgivningen. Vid höga RF, där största delen av fukttransporten i obehandlad betong sker på grund av kapillärkrafter, är ångtransporten fortfarande den dominerande transportmekanismen i impregnerad betong. Fuktfixeringen i betong påverkas av en impregnering och effekten är störst vid höga RF. Det är dock tydligt att en viss mängd fukt finns inuti den impregnerade betongen. Detta kan förklaras med att största delen av kapillärporerna påverkas av impregneringen medan gelporerna förblir obehandlade. Resultaten indikerar också att fuktnivån vid impregneringstillfället avgör vilken del av porsystemet som kan behandlas och inte bara koncentrationen och inträngningsdjupet. Långtidsegenskaperna hos impregneringen kan delas upp i yt- och djupeffekt. Effekten på ytan avtar normalt sett inom ett år på grund av damm och partiklar, UV-ljus, slitage mm. Djupeffekten påverkas däremot inte av dessa faktorer och kan finnas kvar i decennier. Vattenavvisande impregneringar är inte lösningen på alla fuktrelaterade problem i betong, men om de används på rätt sätt så kan det förlänga livslängden på många konstruktioner. Detta leder till ett bättre hushållande med naturresurser och därmed både ekonomiska och miljömässiga besparingar för samhället. / QC20100715

Monitoring is an important tool for gaining insight into an organisation’s environmental performance and for learning about the environmental condition and the effectiveness of environmental management measures. Development of environmental monitoring has generally relied on research aiming at improving monitoring methodology, technique or practice within a particular management tool. Little empirical research has taken into account the organisation’s reality where several management tools are used in parallel. This thesis analyses the practice of environmental monitoring in public authorities with the aim of identifying barriers and possibilities for environmental monitoring as an instrument for improving environmental performance, using the Swedish Rail Administration as a case organisation. The study identified two different types of environmental monitoring: environmental performance measurement (EPM) and activity monitoring, both important for achieving environmental improvements. EPM involves gathering and evaluating data to determine whether the organisation is meeting the criteria for environmental performance set by the management of the organisation. EPM can further be used for judging the success and failure of environmental objectives and strategies. Activity monitoring provides each project of the organisation with information to minimise the negative effects on the natural environment or human health and to ensure that the organisation’s operations conform with regulations. Problems encountered comprised a variety of little co-ordinated monitoring activities, poor utilization of the monitoring results as well as limited internal feedback on monitoring results. Some of the problems identified seem to be an effect of the management transition from a traditional ‘command and control’ system to a self-administered organisation managed by economic incentives and voluntary management systems. This thesis suggests several improvements to make monitoring more efficient. Primarily, the monitoring systems must have a clear structure and be adapted to its specific function. The EPE system would benefit from being integrated with the organisation’s central performance measurement, presenting progress towards organisational strategic objectives as well as operational objectives. The system for activity monitoring must not only focus on inputs and outputs to the system but must also include the environmental condition of the system. In order to improve communication and learning, monitoring data within both EPE and activity monitoring must be better transmitted and utilised within the structure of the permanent organisation. Experience from all monitoring activities that now is scattered and inaccessible to the individuals of the organisation could beneficially be stored within a well-structured organisational ‘memory‘. Such a system would facilitate an iterative management process where the monitoring results and the knowledge gained are used for making future plans and projects more adaptive, thereby improving the environmental performance of the organisation. / QC 20100729

This thesis deals with appropriate legislation concerning common utilities, such as infra-structural facilities and natural resources, which can regulate construction, maintenance, use and financing. Appropriate legislation can be viewed in the two main perspectives, effi-ciency and equity, and the thesis concerns primarily on efficiency. The purpose is to develop an analytical model, which can be used to facilitate structured assessments concerning the management of common utilities. The problem field concerned is of great complexity, and the model is therefore to be viewed as a support for decision-making, not as an instrument capable of delivering ready-made solutions. To structure the problem area it’s divided into three parts, the social, physical and institu-tional environments. The social environment is concerned with factors, such as group size and amount of trust and social capital, which can influence the feasibility of co-operation. The analysis leads to a classification of three social groups: Close-knit, loosely-knit and anonymous. The physical environment is concerned with characteristics of utilities, which influences need for, and feasibility of, co-operation. Rivalry of use and excludability are identified as important factors in this aspect. By combining them six types of goods can be identified: Private goods, club goods, common pool resources, toll goods, public goods and local pub-lic goods. The institutional environment is concerned with rules, which can control the use of com-mon utilities. Two concepts are identified as pivotal: property rights regimes and decision-making procedures. There are four property rights regimes: Individual rights, group rights, public rights (limited and unlimited) and no rights. Furthermore there are three decision-making procedures: Market regulation, group decision-making and public decision-making. A fourth possibility is no decision making-forum. By linking together social groups and types of goods a matrix is obtained in which each square represents a unique combination of social and physical environment. In this analyti-cal framework it is analysed which combinations of property rights regimes and decision-making procedures that are best suited to each square. In the end, Swedish legislation on roads, water and sewerage installations and aesthetic design of buildings is analysed with aid of the analytical model. / QC 20100825

This doctoral thesis deals primarily with condition assessment of road equipment. The road equipment concept is defined by five main groups, road lighting, fences and barriers, vertical signs, horizontal signs and traffic signals, respectively. Of these groups, road markings, street lighting and barriers of three-lane roads have been studied more in detail. A state-of-the-art, comprising information obtained by comprehensive literature studies on condition assessment of road equipment is presented. Comparably few fundamental studies were found, which, to some degree, can be explained by the lack of suitable physical measurement methods. However, in the case of road marking retroreflectivity, mobile instruments have been developed, and research published in this area is relatively comprehensive. Furthermore, although not based on mobile measurements, several studies on assessments on performance of road sign sheeting have been published. The experimental part of the thesis is divided into four studies, of which two are dealing with mobile measurement of wet road markings and street lighting, respectively. One of the studies concerns condition assessment of road marking performance accomplished in the Nordic countries. Finally, one study comprises risk analysis related to crashes into the barriers on three-lane roads. At road equipment condition assessment, mobile measurement methods are preferable compared to stationary methods. However, many relevant parameters are tricky to measure at speed. One example in this connection is characterization of performance of wet road markings, which has to be based on one or more parameters obtained by measurements on dry surfaces. Results presented in this thesis indicate that retroreflectivity and skid resistance of wet road markings can be predicted based on retroreflectivity and macro-texture of dry road marking. For traffic safety, street lighting is important. The performance of this type of road equipment is in most cases described in terms of luminance of the illuminated road surface. However, luminance measurements are tricky and time-consuming and not useful for condition assessment. On the contrary, measurement of illuminance is easy to carry out and can be performed at speed. One part of the thesis describes how road surface luminance in street lighting can be estimated based on illuminance and reflection properties of the road surface. With the purpose of comparing road marking performance in the Nordic countries, condition assessment using mobile measurement equipment was accomplished in 2002 and 2003. In each of the five Nordic countries, a number of roads were chosen for measuring retroreflectivity. The study showed that the retroreflectivity of edge, centre and lane lines was poor in some countries, but, at least regarding edge lines, this shortcoming could be compensated by use of wide, continuous lines. In other words, the visibility of longitudinal road markings was approximately equal in the different countries. The purpose of the risk analysis performed on three-lane road barriers was to estimate the influence of the time-period between initial crash and repair on the risk of a secondary accident. The result showed that, especially in winter-time, time-reduction means reduced risk of secondary accidents. / QC 20100824

The focus of this study is on potential damages to buildings resulting from expansive soils in Tanzania, particularly clay soils in Kibaha. For the fact that most of the affected structures are founded on expansive soils, a clear understanding of the behaviour of soils and their interaction with structures has been of interest to the study in order to evaluate properly the source of the problem.The geotechnical behaviour of expansive clay soils is investigated by looking into the geomorphologic, geological and climatic conditions and mineralogical composition of the soils in the study area.Two sites, representative of known problem-areas in Kibaha were selected for geotechnical tests. Geotechnical site investigation consisted of open trial pits, profile description and the collection of both disturbed and undisturbed samples. To extend and amplify the findings, supplementary samples were collected from the environs of the two sites.The collected samples were submitted to soil laboratories at KTH, ARU, SEAMIC and DIT for mineralogical composition tests, natural water content, density, Atterberg limits and swell tests. The results of this investigation indicate that soils in Kibaha contains clay (31%), have high liquid limit (59%) and plastic limit (37%) which indicate high potential swell.Since swell pressure, free swell and swell percent are key properties of expansive soils, the swell properties were measured by free swell tests and one-dimensional oedometer swell tests. The free swell ranged from 100% to 150% and the swell pressure was in the region of 45 kPa. The coefficient of linear extensibility (COLE) was determined for characterizing expansive clays. For all tested samples, COLE ranged from 0.09 to 0.14 indicating that soils fall in the region of high to very high expansion potential rating. The properties of expansive soils were confirmed by the x-ray diffraction test which showed the presence of smectite in the soil. Furthermore, total suction measurement technique using filter paper method indicated that the soils have high suction values, signifying that they have a tendency to swell upon wetting depending on plasticity of particular soil.The depth of the active zone was measured as a function of moisture variations in the profiles during two extreme weather conditions. The active zone depth was found to be between 1.0 and 2.0 m deep. Procedures to assess models to predict swell in the case study were outlined together with their validity.Vertical and horizontal spatial variability in selected soil properties was defined using geostatistical techniques through the fitting of variogram. The indicator semivariograms of both clay contents and free swell gave a range of 20 m horizontally and 1.0 m vertically, with the horizontal variograms exhibiting greater ranges than the dipping variograms.Physical conditions of the surveyed properties in the area confirmed that building damages are associated with poor building materials triggered by expansive soils. In support of the obtained data, the actual behaviour of the foundations was supplemented with prototypes of strip foundations whose performances were monitored over a period of four months. Finally, suggested are the ways forward to solve the problem of foundation on expansive soil / QC 20100824