Framework for Life-Cycle Cost Analysis of Trenchless Renewal Methods for Large Diameter Culverts

摘要

According to the Federal Highway Administration of the U.S. Department of Transportation, there are more than 4.1 million miles of road in total length, making it the world's longest and biggest road network with millions of culverts hidden underneath road in the United States. Trenchless technologies rehabilitation employ innovative methods, materials, and equipment that require minimum surface excavation and access. Trenchless technologies can be used when other conventional methods, such as open-cut methods are not applicable or cost-effective. Life-cycle cost analysis (LCCA) is an analytical method used to evaluate long-term investment options, and facilitate the associated costs which consists of three main modules as construction, environmental, and social costs. The objective of this paper is to develop a framework for LCCA for trenchless renewal methods for large diameter culverts and to identify and categorize the potential factors which contribute to LCCA with the help of literature review. It is found that host pipe length and diameter, rehab material, rehab thickness, and rehab design life were the key factors to construction cost. Also, material components, volume of materials, material transportation, project duration and location, and installation equipment were the main influencing factors to environmental cost. Last but not least, study shows that the location and duration of the project, type of traffic control, traffic peak, average annual daily traffic (AADT), pavement restoration cost, and noise indicator were the major potential factors to social cost. It can be concluded that many quantifiable factors are involving to have comprehensive evaluation of LCCA as an essential element when considering trenchless renewal of large diameter culverts. This framework can be utilized to evaluate LCCA in large diameter culverts for different trenchless renewal projects.