Cracking Of Concrete In The Tuscaloosa Lock

THE TUSCALOOSA LOCK WAS CONSTRUCTED ON THE WARRIOR RIVER NEAR TUSCALOOSA, ALABAMA, BETWEEN 1937 AND 1939. IT WAS NOTED IN 1947 THAT CRACKS HAD DEVELOPED IN THE LOCK WALLS. A BOARD OF CONSULTANTS WAS APPOINTED, AND THE MEMBERS OF THE BOARD EXAMINED THE STRUCTURE AND RECOMMENDED THAT THE CONCRETE RESEARCH DIVISION, WATERWAYS EXPERIMENT STATION, CONDUCT A STUDY TO DETERMINE THE CAUSE OF THE CRACKING. THE DATA DEVELOPED ARE SUMMARIZED AND DISCUSSED. IT WAS CONCLUDED THAT THE CRACKING RESULTED FROM A CHEMICAL REACTION BETWEEN THE ALKALIES IN THE CEMENT AND UNSTABLE SILICA IN THE AGGREGATE. IT IS BELIEVED THAT THIS IS THE FIRST PUBLISHED ACCOUNT OF CRACKING OF CONCRETE THROUGH CEMENT-AGGREGATE REACTION IN WHICH CHALEDONIC CHERT IS THE MAJOR CONTROL RESPONSIBLE FOR THE DELETERIOUS REACTION. /AUTHOR/