Presentation on theme: "Performance of Exposed Aggregate Surface of Composite Pavements at MnROAD Bernard Izevbekhai Alexandra Akkari Minnesota Department of Transportation International."— Presentation transcript:
Performance of Exposed Aggregate Surface of Composite Pavements at MnROAD Bernard Izevbekhai Alexandra Akkari Minnesota Department of Transportation International Symposium on Pavement Performance Trends Advances and Challenges ASTM Committee E17 on Vehicle Pavement Systems Tampa Florida December
MNROAD MAINLINE Interstate 94 Westbound Live Traffic 28,000 AADT Mainline Passing Lane Vs. Driving Lane Traffic; ESALs Total Truck Volume 15% approx.
Introduction Targets of EA Surface Quiet pavement surface Increased durability Increased friction Objective of Composite Pavement Minimize cost with high quality EA surface layer over low cost (relaxed gradation) layer Sustainability Investigate Cost effectiveness of 2-lift Concrete Cell 70Cell 71Cell 72 Innovative Diamond Grind Traditional Diamond Grind Exposed Aggregate 3" HMA3" EAC 6" RAC 6" CHP 8" Class 58" Class 68" Class 7 Clay Composite Cells Compare EAC to cells 70 and 71 to evaluate performance
Mix Design Fly Ash15% Water (lbs/cy)283 Cement (lbs/cy) (Type I/II) (SG=3.15) 616 Fly Ash (lbs/cy) (Class C/F) (SG = 2.5) 109 W/CM0.39 C. Sand (OD lbs/cy) (SG = 2.63) (Abs= 0.90%) 843 CA1 (OD lbs/cy) (1/2 W. Chips, SG=2.72, Abs= 0.40%) 1133 CA2 (OD lbs/cy) (3/8 W. Chips, SG= 2.72, Abs= 0.40%) 843 Max Slump (in)3 % Air7 Multi-Air 25 (oz/cy) Adm 686 (oz/cwt)1 - 5 Adm 3 (oz/cwt) (as needed for slump retentions) % Passing 3/8
Performance Evaluation On Board Sound Intensity AASHTP TP Friction ASTM E-247 International Roughness Index ASTM E-950 Profile Depth ASTM E-2157 Sound Absorption ASTM E-1050
Ride Quality Anomalous laser-induced IRI was not observed in EAC.
SPIKINESS CONCEPT & QUANTIFICATION dx
Conclusions EAC does not provide significant noise reduction higher OBSI than both the HMA and traditional diamond grind. Innovative diamond grinding of composite pavements may be beneficial for noise reduction lower OBSI than the HMA, EAC, traditional DG surfaces, and higher sound absorption than EAC. EAC can provide more than adequate friction for driver safety, but does not show any improvement from typical HMA or DG. Anomalous laser-induced IRI was not observed in EAC. Going Forward Changing the quality and type of aggregate in EAC could lead to a change in texture orientation / spikiness and improve surface performance. Need to examine Elongation, flatness etc in mix design to minimize spikiness.