DURABILITY FIELD INVESTIGATION OF AN ABANDONED CONCRETE BRIDGE

摘要

A summary of a detailed field and laboratory investigation, consisting of over 12000 different electrochemical, chemical, physical and mechanical tests undertaken on the abandoned Dickson Bridge in Montreal, is presented. Constructed in 1959, this bridge was abandoned in 1993, after the 1990-92 inspection showed severe delamination, and low air and high chloride contents significantly different from the acceptable threshold levels. Six industrial partners (Corrpro, Inc, PJ Consultants Ltd, SIKA Canada Ltd, SIREM Inc, the City of Montreal and Geo-Centers Inc.) and Queen's University of Belfast, Northern Ireland were involved in the project. The univariate analysis of the results showed considerable scatter, while multivariate analyses (not reported here) correlated the results from the various tests to determine the significance of the various parameters, which caused extensive early deterioration of the bridge. Besides being beneficial to the practising engineers in planning economic condition surveys, the related data bank and the statistics are being used presently to develop a reliability-based method of design for durability against corrosion of the reinforcing steel.