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On- and off-site construction activities during transport infrastructure projectsare major contributors to greenhouse gas (GHG) emissions. The SwedishTransport Administration (STA) has stated the goal of gradually reducing itsemissions from transport infrastructure projects to zero by 2050. However,current life cycle assessment (LCA)-based approaches for estimating GHGemissions are static and location-independent, and thus do not account for thedynamics of construction. Some project-based methods have been proposed,but there is little guidance and insight available to facilitate theirimplementation in real projects during project planning.This thesis aims to explore how CO2 emissions can be reduced during differentstages of the planning process for transport infrastructure. The analysis focuseson emissions during project execution, i.e. on- and off-site constructionactivities including material production, and transportation. An exploratoryresearch approach is used to develop practical CO2 reduction methods thatcould be implemented during the feasibility studies, the design stage, and theprocurement stage of the planning process. These methods and models aredeveloped and demonstrated in case studies. This is a similar to the prototypingmethod in which early drafts of a new system are developed and tested toenable further development into a finalized system. The findings show thatconsiderable CO2 reductions can be achieved if project alternatives areevaluated systematically during the planning process. Although most majordecisions are made during the early stages of the planning process, later stagesshould not be ignored because these offer opportunities to include moredefinitive project data and thereby improve the certainty of the assessments.Future research in this area should look at the entire planning process up to thestart of construction.

Complex road projects, particularly near sensitive locations, often have substantial effects on humans and theenvironment caused by construction, production processes and the use phase. Before a road alignment isdetermined, several road corridors are identified and evaluated during early planning stages. Oftentimes thisevaluation focuses on impacts of the finished road whereas construction and production processes frequently areignored, risking viable corridors to be discarded before having been sufficiently evaluated. Existing IT-systemsenables modeling of relevant aspects such as road corridors, noise, pollution, production and construction, butthere is often a lack of interoperability between these systems. Interoperability problems can be faced withExtract Transform Load (ETL) tools but this has not been adequately examined regarding infrastructure projects.Our study presents a novel method for evaluating road corridors that includes production aspects, which arevisualized and analyzed in 3D. By using ETL technology to handle interoperability problems, existing tools forroad corridor planning, production planning and 3D visualization are used to demonstrate the method. Thefindings indicate that large scale production aspects related to road corridors can be modeled, analyzed andvisualized in 3D, which can benefit stakeholders in making decisions.

Road construction operations often require considerable amounts of energy in the form of fossil fuels, thus generating considerable greenhouse gas (GHG) emissions. While fuel efficiency of the heavy construction equipment is extensively studied, limited attention is given to how the construction process can be planned in order to reduce energy use and GHG-emissions. In this paper a conceptual model is proposed for the assessment of energy use and GHG-emission in road construction projects. When applied to a case study the conceptual energy model is a useful tool to asses and evaluate project alternatives in the early planning stages of road construction projects. As a result both the energy use and GHG-emissions in road construction projects can be reduced. Godkänd; 2014; 20141202 (jankra)

With growing concern for rising fuel prices, peak oil, global warming and climate change in the last few decades, efforts have been made to address and alleviate the possible problems resulting from these threats. Within the transport sector these efforts have been made largely with respect to fuel efficiency of vehicles and alternative fuels. However one aspect not addressed to any great extent is the construction of the transportation infrastructure such as roads and railroads although it is known that this process consumes a lot of energy and causes emissions of greenhouse gases.The main idea behind this thesis is to formulate an energy model in order to assess energy use and greenhouse gas emissions in road construction projects. The scope of the thesis focuses on what is called the earthworks which includes the mass hauls, cutting, filling and crushing of materials. The process of forming the energy model was lead with the help of the following research questions:RQ 1: How can earthworks be optimized in a road construction project?RQ 2: How can energy consumption and greenhouse gas emissions of earthworks be assessed with the data available in the planning stage?RQ 3: What is the relationship between energy consumption and greenhouse gas emissions in road construction projects?The proposed energy model helps understanding the energy use in earthworks processes and is complemented with equations for calculating the corresponding energy use. Implementing the model in road projects requires a bill of mass quantities, a mass haul plan and a production plan. Knowledge about the location and project is helpful for further improving the accuracy of assessments when implementing the model.. In the model the energy use of earthworks is divided into three categories of machines or vehicles namely hauling vehicles, off-road mobile machines and crushing plants. Each category requires different methods for assessing their energy use.The application of the earthworks energy model is analyzed using a case study, based on two road projects in the city of Kiruna in Sweden. The source of crushed aggregates for the base course and subbase of the roads are compared. One alternative is to use nearby sources of gangue which is a by-product of the mining industry. This material can be crushed by a mobile crushing plant next to the road line. The other alternative is to buy these products from LKAB, the local mining corporation which also runs a stationary crushing plant located further away from the road projects. The first alternative will mean shorter mass hauls but might require its mobile crushing plant to run by a diesel electric generator instead of electricity from the grid. The latter issue turns out to be of crucial importance when the earthworks energy model is applied to the case study. In short, unless the energy source of the crushing of aggregates is electricity then the second alternative pays off even if the hauls are longer.One conclusion from the case study is that crushing of aggregates is a very energy consuming activity. Therefore it is an activity worth paying close attention to in order to improve the accuracy of its energy consumption. The fuel consumption of mass hauls is another aspect. It is not so well known how much the fuel consumption can differ between articulated haulers and trucks with trailers under given circumstances. They are designed for different types of conditions and hauling distances but there is an area where these uses overlap and within this area it is important to be able to establish which type of vehicle is the most energy efficient.The earthworks energy model is by no means complete. It is possible to expand it to involve more activities in road construction projects as well as increasing the detail. One way to increase the detailing in the energy evaluation is to connect it closer to the production planning and the implementation and use as a module in a planning software such as DynaRoad, which was used in the case study of this thesis. While increased detail and improved accuracy is important, what’s perhaps more important is to make the model more user friendly in order to spread its use to a wider audience. Validerat; 20130611 (ysko)