Life Cycle Sustainability Performance Assessment Method for Comparison of Civil Engineering Works Design Concepts: Case Study of a Bridge

Standardized and transparent life cycle sustainability performance assessment methods are essential for improving the sustainability of civil engineering works. The purpose of this paper is to demonstrate the potential of using a life cycle sustainability assessment method in a road bridge case study. The method is in line with requirements of relevant standards, uses life cycle assessment, life cycle costs and incomes, and environmental externalities, and applies normalization and weighting of indicators. The case study involves a short-span bridge in a design-build infrastructure project, which was selected for its generality. Two bridge design concepts are assessed and compared: a concrete slab frame bridge and a soil-steel composite bridge. Data available in the contractor’s tender phase are used. The two primary aims of this study are (1) to analyse the practical application potential of the method in carrying out transparent sustainability assessments of design concepts in the early planning and design stages, and (2) to examine the results obtained in the case study to identify indicators in different life cycle stages and elements of the civil engineering works project with the largest impacts on sustainability. The results show that the method facilitates comparisons of the life cycle sustainability performance of design concepts at the indicator and construction element levels, enabling better-informed and more impartial design decisions to be made

A harmonized method for automatable life cycle sustainability performance assessment and comparison of civil engineering works design concepts

The life cycle sustainability performance of civil engineering works is increasingly important. The possibility to influence the sustainability of a project design is larger in the conceptual stage than in later stages. Better-informed decisions regarding design choices’ impact on sustainability can be made by comparing conceptual project designs based on an assessment of their life cycle sustainability performance. It is essential that concepts are assessed in a harmonized way and compared impartially. Current standards provide the general framework for the assessment of sustainability performance, but do not give detailed guidance on calculation of sustainability indicators and their aggregation. Since design in automated systems is becoming increasingly common, there is a growing need for machine-readable data and automatable assessment methods. Assessment methods which can be applied using open-access data is important to achieve fair competition. This paper aims to provide a method for life cycle sustainability performance assessment and comparison of civil engineering works design concepts, possible to apply using open-access Environmental Product Declarations (EPDs) and life cycle assessment (LCA) data. The purpose is to enable fair and automatable sustainability assessments of design concepts, to facilitate impartial comparisons of such assessments as a basis for choosing sustainable designs. A literature review of relevant standards and scientific papers on sustainability assessment of construction and civil engineering works was performed. A harmonized, fair and automatable method for life cycle sustainability assessment and comparison of civil engineering works design concepts, well-suited for optimization purposes, is presented. However, the aim currently limits categories and indicators possible to include. The proposed method includes guidance on the calculation of environmental, social and economic indicators, based on LCA, life cycle costing (LCC) and external costs, and aggregation using normalisation and weighting factors of the Product Environmental Footprint (PEF). The proposed method allows for an impartial comparison of the sustainability of design concepts, resulting in better-informed decisions

Multi-criteria decision analysis methods to support sustainable infrastructure construction

The construction of infrastructure projects represents a large sustainability impact, both positive and negative. Increased positive and reduced negative impacts can be achieved through better design and planning of the construction. To make more sustainable choices, well‐defined predictive sustainability assessment methods are required. Multi‐criteria decision analysis (MCDA) is a well-suited method for predictive sustainability assessment. This paper evaluates two MCDA methods for sustainability assessment of infrastructure construction and exemplifies their application with two case studies. The aim of this paper is to discuss if the methods are suitable for identifying the most sustainable alternative during the procurement process of an infrastructure project. It is recommended that MCDA methods are further developed to comply with the recently published EN standard on sustainability assessment of civil engineering works

Traffic-related microplastic particles, metals, and organic pollutants in an urban area under reconstruction

In urban environments, particularly areas under reconstruction, metals, organic pollutants (OP), and microplastics (MP), are released in large amounts due to heavy traffic. Road runoff, a major transport route for urban pollutants, contributes significantly to a deteriorated water quality in receiving waters. This study was conducted in Gothenburg, Sweden, and is unique because it simultaneously investigates the occurrence of OP, metals, and MP on roads and in stormwater from an urban area under reconstruction. Correlations between the various pollutants were also explored. The study was carried out by collecting washwater and sweepsand generated from street sweeping, road surface sampling, and flow-proportional stormwater sampling on several occasions. The liquid and solid samples were analyzed for metals, polycyclic aromatic hydrocarbons (PAH), oxy-PAH, aliphatics, aromatics, phthalates, and MP. The occurrence of OP was also analyzed with a non-target screening method of selected samples. Microplastics, i.e. plastic fragments/fibers, paint fragments, tire wear particles (TWP) and bitumen, were analyzed with a method based on density separation with sodium iodide and identification with a stereo microscope, melt-tests, and tactile identification. MP concentrations amounted to 1500 particles/L in stormwater, 51,000 particles/L in washwater, and 2.6 7 106 particles/kg dw in sweepsand. In stormwater, washwater and sweepsand, MP ≥20 μm were found to be dominated by TWP (38%, 83% and 78%, respectively). The results confirm traffic as an important source to MP, OP, and metal emissions. Concentrations exceeding water and sediment quality guidelines for metals (e.g. Cu and Zn), PAH, phthalates, and aliphatic hydrocarbons in the C16–C35 fraction were found in most samples. The results show that the street sweeper collects large amounts of polluted materials and thereby prevents further spread of the pollutants to the receiving stormwater

Subsurface Environmental Impact in Urban Areas. Shallow Groundwater Composition, Corrosion of Soil-Buried Constructions, and Leachates from Reclaimed Asphalt Pavement

Worldwide, groundwater represents the largest and most important source of potable water. Usually, urbanisation affects shallow urban aquifers in two ways: by radically changing patterns and rates of aquifer recharge, and by adversely affecting the quality of groundwater. The overall objective of this thesis is to illuminate multiple subsurface environmental problems in urban areas. The urban environment, first described generally, is thereafter treated from three angles: (1) leakage water from stockpile storage of reclaimed asphalt pavement (RAP) as a source of groundwater contamination; (2) urban shallow groundwater quality, exemplified by the conditions in G\uf6teborg; and (3) corrosion of soil-buried structures as an effect of the composition of the soil, soil water and groundwater. In the asphalt investigation both field and laboratory works were included. Several semi-volatile compounds were identified frequently in the leakage water from the field stockpiles. The laboratory column test differs in that the concentrations of the compounds were much lower, and the compounds were fewer and to some extent different. The main reason was the much higher ratio of liquid to solid in the column tests than in the field. The most common semi-volatile compounds found in the leakage water from RAP were also observed in shallow urban groundwater, the quality of which was investigated in eighteen observation wells; it was shown that the quality differs greatly from that of rural areas, normally by greater ion strength and a much higher alkalinity. Although the composition of the filling material caused the high alkalinity, the natural geological material also had an influence. The soil analysis from the field corrosion investigation showed large differences between samples taken from places as close to each other as half a metre, which highlights the heterogeneity of the filling material. Results showed that the heterogeneity of the filling material stimulated the corrosion process of soil-buried panels of carbon steel and zinc; however, the high alkalinity of the soil water and the groundwater and the high total hardness of the filling material both retard the corrosion rate

Subsurface Environmental Impact in Urban Areas. Shallow Groundwater Composition, Corrosion of Soil-Buried Constructions, and Leachates from Reclaimed Asphalt Pavement

Worldwide, groundwater represents the largest and most important source of potable water. Usually, urbanisation affects shallow urban aquifers in two ways: by radically changing patterns and rates of aquifer recharge, and by adversely affecting the quality of groundwater. The overall objective of this thesis is to illuminate multiple subsurface environmental problems in urban areas. The urban environment, first described generally, is thereafter treated from three angles: (1) leakage water from stockpile storage of reclaimed asphalt pavement (RAP) as a source of groundwater contamination; (2) urban shallow groundwater quality, exemplified by the conditions in G\uf6teborg; and (3) corrosion of soil-buried structures as an effect of the composition of the soil, soil water and groundwater. In the asphalt investigation both field and laboratory works were included. Several semi-volatile compounds were identified frequently in the leakage water from the field stockpiles. The laboratory column test differs in that the concentrations of the compounds were much lower, and the compounds were fewer and to some extent different. The main reason was the much higher ratio of liquid to solid in the column tests than in the field. The most common semi-volatile compounds found in the leakage water from RAP were also observed in shallow urban groundwater, the quality of which was investigated in eighteen observation wells; it was shown that the quality differs greatly from that of rural areas, normally by greater ion strength and a much higher alkalinity. Although the composition of the filling material caused the high alkalinity, the natural geological material also had an influence. The soil analysis from the field corrosion investigation showed large differences between samples taken from places as close to each other as half a metre, which highlights the heterogeneity of the filling material. Results showed that the heterogeneity of the filling material stimulated the corrosion process of soil-buried panels of carbon steel and zinc; however, the high alkalinity of the soil water and the groundwater and the high total hardness of the filling material both retard the corrosion rate