Service Records of Chicago District Breakwater Stone and How These Relate to Test Results

Stank, Kevin R.; Knox, James W.; ,

Service Records of Chicago District Breakwater Stone and How These Relate to Test Results

by Kevin R. Stank, U.S. Army Corps of Engineers, Chicago, United States,
James W. Knox, U.S. Army Corps of Engineers, Chicago, United States,

Document Type: Proceeding Paper

Part of: Durability of Stone for Rubble Mound Breakwaters

Abstract:

Breakwater stone production is limited to areas with geologic outcrops capable of producing large rocks. The most reliable breakwater stone is that which exhibits the highest degree of homogeneity, and is free from blast fractures and weakening sedimentary structures. Stone selectively quarried for use as building stone is generally more homogeneous than stone quarried as aggregate, and lacks problems associated with blast fractures. Laboratory test results of selectively quarried material are more representative of the final product and tend to be more reproducible. Cut stones have survived freeze/thaw conditions on Lake Michigan for over 60 years as have igneous stones blast quarried from Wisconsin granite. In contrast, stones produced as a by-product from nonselective, high volume aggregate production, are showing signs of deterioration after 5 years of service. Durability tests accurately predict the behavior of stones on the breakwater, providing an adequate number of samples are taken.

Return to search