Quantity of CO2 Emissions in the Life Cycle of a Highway Infrastructure

There is strong evidence to indicate that carbon dioxide and other greenhouse gases are accumulating at unprecedented concentrations in out atmosphere contributing to global climate change. Evidence is equally strong that human activities, mainly the burning of fossil fuels, are driving force in this process (IPCC 2007). While different industries contribute varying amounts to total anthropogenic greenhouse gases, it is incumbent upon each to understand its contribution and search for sensible ways to reduce overall greenhouse gas production. The aim of this paper is the development of a methodology to determine the amount of CO2 emissions of a highway, allowing providing solutions that can improve the energy footprint and reduce its emissions

Quantity of CO2 Emissions in the Life Cycle of a Highway Infrastructure.

The complexity of climate change and its evolution during the last few years has a positive impact on new developments and approaches to reduce the emissions of CO2. Looking for a methodology to evaluate the sustainability of a roadway, a tool has been developed. Life Cycle Assessment (LCA) is being accepted by the road industry to measure and evaluate the environmental impacts of an infrastructure, as the energy consumption and carbon footprint. This paper describes the methodology to calculate the CO2 emissions associated with the energy embodied on a roadway along its life cycle, including construction, operations and demolition. It will assist to find solutions to improve the energy footprint and reduce the amount of CO2 emissions. Details are provided of both, the methodology and the data acquisition. This paper is an application of the methodology to the Spanish highways, using a local database. Two case studies and a practical example are studied to show the model as a decision support for sustainable construction in the road industry.

Influence of the rheological behaviour of the lubricant on the appearance of pitting in elastohydrodynamic eegime

This paper analyses the influence of lubricant behaviour on the appearance of pitting. It attempts to study the effect of viscosity?pressure relation, compressibility, film thickness?roughness relation and friction coefficient on pitting failure of the contacting elements.To explain these effects, we first deal with the influence of the oil on the lubrication of the contact using elastohydrodynamic theory and secondly two multiaxial fatigue criteria are used, Crossland criterion and Dang Van criterion, to evaluate the influence of the rheology on the appearance of pitting. Finally, different applications are presented together with a discussion on the results obtained.