Product and process platforms have been promoted as possible enablers of increased productivity in civil engineering. However, such platforms are traditionally applied in mass manufacturing industries where production assets are employed in continuous production of uniform products, which strongly facilitates continuous improvement. The discontinuous nature of project-based production in civil engineering restricts such possibilities. Thus, if platforms are implemented there is a need for methods capable of evaluating the performance of integrated product and production process configurations in specific projects. A possibility, explored in this paper, is to use database-driven simulation. As a case study, a configurable simulation model, based on standardized process patterns and values stored in a platform, has been developed of the production for a bridge concept. The presented results provide evidence that database-driven simulation can support efficient platform evaluation and development by ...

Greenhouse gas (GHG) emissions from construction processes are a serious concern globally. Of the several approaches taken to assess emissions, Life Cycle Assessment (LCA) based methods do not just take into account the construction phase, but consider all phases of the life cycle of the construction. However, many current LCA approaches make general assumptions regarding location and effects, which do not do justice to the inherent dynamics of normal construction projects. This study presents a model to assess the embodied energy and associated GHG emissions, which is specifically adapted to address the dynamics of infrastructure construction projects. The use of the model is demonstrated on the superstructure of a prefabricated bridge. The findings indicate that Building Information Models/Modeling (BIM) and Discrete Event Simulation (DES) can be used to efficiently generate project-specific data, which is needed for estimating the embodied energy and associated GHG emissions in construction settings. This study has implications for the advancement of LCA-based methods (as well as project management) as a way of assessing embodied energy and associated GHG emissions related to construction.

Meeting increasingly ambitious carbon regulations in the construction industry is particularly challenging for earthmoving operations due to the extensive use of heavy-duty diesel equipment. Better planning of operations and balancing of competing demands linked to environmental concerns, costs, and duration is needed. However, existing approaches (theoretical and practical) rarely address all of these demands simultaneously, and are often limited to parts of the process, such as earth allocation methods or equipment allocation methods based on practitioners’ past experience or goals. Thus, this study proposes a method that can integrate multiple planning techniques to maximize mitigation of project impacts cost-effectively, including the noted approaches together with others developed to facilitate effective decision-making. The model is adapted for planners and contractors to optimize mass flows and allocate earthmoving equipment configurations with respect to tradeoffs between duration, cost, CO2 emissions, and energy use. Three equipment allocation approaches are proposed and demonstrated in a case study. A rule-based approach that allocates equipment configurations according to hauling distances provided the best-performing approach in terms of costs, CO2 emissions, energy use and simplicity (which facilitates practical application at construction sites). The study also indicates that trucks are major contributors to earthmoving operations’ costs and environmental impacts.

Case studies have become more common and accepted among researchers across a wide array of academic disciplines including construction engineering and management (CEM) research. Among mainstream case study literature, the case study approach is seen primarily as a research method to be used in social sciences to study social phenomena. However, CEM is not considered a social science and construction engineering (CE) often do not study social phenomena. Instead, the field revolves around quantitative and engineering-based matters. This paper aims at studying the usage and characteristics of case studies in CEM research to determine if current literatures on case studies are sufficient for the field or if new approaches are needed. This is conducted through a quantitative inquiry into data from scientific databases and a qualitative analysis of several case study papers in the field of CEM. The results show that case studies are common in the field and in CE they often are used to demonstrate proposed frameworks or models. However, case study literature does not sufficiently describe this approach to case studies, which suggests that the literature needs to be complemented to meet the needs in CEM research.

Construction and operation of buildings and infrastructure is a main contributor to emissions of greenhouse gases (GHG) in Sweden. The embodied energy of construction, meaning all the energy that is used until the completion of the construction project (see Figure 1), cause roughly 10 million tones of CO₂ equivalent emissions each year which equals to the emissions from all cars in Sweden (IVA 2014). About 6 million tones of CO₂ equivalent emissions are attributed to the embodied energy of roads, railroads and other civil works while the remaining 4 million tones are attributed to the embodied energy of buildings (IVA 2014). Although reducing energy use and associated GHG-emissions in road and railroad construction is prioritized by the Swedish Transport Administration (Trafikverket 2012), the GHG-emissions from such construction projects have increased in recent years (Boverket 2014). Many of the existing efforts to reduce energy use and associated GHG-emissions focus on individual phases of the life cycle and don’t take into consideration the effects at other stages during the whole life cycle of a project (Boverket 2011). A crucial step in the assessment of energy use and associated GHG-emissions is to clarify and categorize the different phases of a life cycle. Figure 1 shows a proposed categorization of life cycles phases and use of energy based on previous research (Davies et al. 2014). Buildings’ main use of energy happens during its operational phase from e.g. heating, lighting and use of electrical appliances (Sartori and Hestnes 2007). In infrastructure projects such as road construction the embodied energy is roughly equal to the operational energy for roads with lighting, or in fact considerably higher if the road lacks lighting (Stripple 2001).