ABSTRACT
Parsons Brinckerhoff has been a leader in the rehabilitation of underground structures and in particular highway and rail tunnels for over 20 years. Over that period of time Parsons Brinckerhoff has developed detailed procedures for the inspection and rehabilitation of tunnel structures and their associated systems. Most underground facilities that require rehabilitation are located in urban areas and are a major element of the infrastructure. The rehabilitation of these facilities requires that the facility be maintained in service during the repair/restoration work. As a result of these requirements, special procedures have been developed to facilitate the inspection, design and implementation of the repairs. These procedures require the use of specialty products, construction methods and in most cases prequalification of the contractor. This paper will discuss the procedures used for the inspection, design requirements, and in particular the use of specialty materials, construction practice, and current methodology using case histories to illustrate successful underground rehabilitation projects.
