London Underground: nineteenth century railway, twenty-first century standards

Abstract

London Underground (LU) was the first underground passenger railway in the world. It was extended in three phases by different owners, all of whom used new techniques and materials to reduce costs. Like all pioneering works, some of the techniques and materials proved to have inherent faults, and the changes in ownership and the quest for cost reductions resulted in incomplete records. As a result of these various factors, LU suffered in-service failures. This paper describes failures associated with cast iron, longitudinally timbered bridges and clinker aggregate concrete. It outlines how LU dealt with the failures to enable continued safe operation, the investigations carried out to determine why the failures occurred and the solutions adopted to prevent similar failures occurring in the future. In each of the three cases, the paper explains how investigations into the failures enabled LU to retain the structures and avoid the prohibitive costs of replacement.