Raw Materials Study at Chicago O’Hare Int’l Airport by Francis B. Nelson III Leslie J. Struble

Overview Material Suppliers IDOT Testing Freeze-Thaw (F/T) Performance Alkali Silica Reaction (ASR) Information Shrinkage*

Material Suppliers Sources identified for: –Coarse Aggregate –Fine Aggregate –Cement –Mineral Admixtures

IDOT Approved Materials IDOT has developed lists of Approved Material Suppliers Lists updated constantly Based on extensive testing programs Available online –

IDOT Testing Every supplier is tested by IDOT Tests constantly updated Only IDOT tests allowed Approval Process available from IDOT Majority of producers only use IDOT approved materials near Chicago

Gradations Tech Note IDOT Art vs. ASTM C33

Freeze-Thaw Performance Met with IDOT to discuss their experience –Determined that their F/T rating list of approved suppliers is best suited for this project –IDOT has extensive testing program in place for quarries to be approved –Use the 40 Year Extended Life Pavement Design List

F/T Testing Program Each quarry tested bi-annually 5 Samples run for 350 cycles CA for concrete must be of quality A Prior to F/T Testing IDOT tests for: –Soundness –Los Angeles Abrasion –Minus #200 sieve material –Maximum % Deleterious Material

Quality A Standards

Top Size Allowable

Additional F/T Testing If larger top sized gradations are deemed beneficial Coordinate with IDOT to test for larger sizes Currently use 0.025” expansion for 40 year Design Life List Approval

ASR Information Good performance in Chicago area IDOT has provided: –Preliminary specification –List of approved fine aggregate suppliers UIUC has extensive experience with ASR Samples will be obtained to do testing in our lab –Compare natural sand vs. manufactured sand

Drying Shrinkage Study will be performed on different top size aggregate gradations –CA’s 5, 7, 11, & 14 –Along with a blend of CA 1 & 7 Additional Study to test different cements –Future work

Thank You Any questions/comments?