Concrete and Rock Tests, Major Rehabilitation of Starved Rock Lock and Dam, Illinois Waterway, Chicago District. Phase II. Compliance, Scour Detection

摘要

Drilling for laboratory testing of concrete and foundation rock was carried out for the U.S. Army Engineer District, Chicago, as part of a major rehabilitation program at the Starved Rock Lock and Dam. The structures are on the Illinois Waterway. This report covers the work accomplished during the Phase II program entitled 'Compliance and Scour Detection'. The compliance portion of the work was conducted for purposes of determining selected characterization and engineering design parameters on any foundation materials that were different than previously detected. A secondary purpose of the compliance work was to ascertain the base elevation of the head and taintor gate dams. The scour detection portion of the work was accomplished to determine undercutting of the dam (behind the dam) and the depth of possible scouring behind the taintor gate dam. A loosely cemented sand was discovered under a portion of the head gates dam. Direct shear tests were performed on the material and a cohesion of 0.22 tsf and an angle of internal friction of 27 deg were obtained from the test results. The base of the head and taintor gate dam was found with borings to be significantly different than that shown on original working drawings. of 26 borings through the head and taintor gate dam, 20 showed the base elevation of the dam to be deeper than that shown on the working drawings. Six borings through the head gate dam showed the base of the dam to be resting on the loosely cemented sand and as much as 5.3 ft above the base elevation shown on the original working drawings.