Life Cycle Assessment of Portland Cement Concrete Interstate Highway Rehabilitation and Replacement

摘要

Life Cycle Assessment (LCA) is a tool that can be used to identify ways to decrease the environmental impact of a product or process and to inform decision makers of the consequences of changes to the product or process. LCA encompasses all aspects of a process or product from 'cradle to grave', including material extraction, transport, production, maintenance, and removal or recycling. This study is a comparative LCA of three different replacement options for an aging Portland cement concrete (PCC) highway: Replacement with a new PCC pavement, replacement with hot mix asphalt (HMA) pavement, and cracking, seating and overlaying (CSOL) the existing pavement with HMA. Each LCA includes an appropriate maintenance schedule so that the pavements will have a 50 year life span and can be reasonably compared. The environmental impacts have been assessed according to common environmental concerns, such as global warming potential and acidification. This paper summarizes those impacts and provides information and recommendations to build greener highways in Washington State.