1. Portorož, Slovenia Quantifying the Impact of Jointed Concrete Pavement Curling and Warping on Pavement Unevenness George Chang, PhD, PEGeorge Chang, PhD, PE Transtec GroupTranstec Group Project ManagerProject Manager gkchang@theTranstecGroup.comgkchang@theTranstecGroup.com T RANSTEC GROUP THE

2. Portorož, Slovenia US FHWA Curl/Warp Study oImpact of Curling and Warping on JCP Performance

3. Portorož, Slovenia Outlines oCurl/Warp Measurement oProfile Synchronization and Joint ID o2GCI Curvature Index oRoCK System for Curvature- Impact-Roughess Analysis

4. Portorož, Slovenia Curl/Warp Measurement oWhat to be measured? Site Selection Data Collection oHow to measure? Profiling Temperature Others

5. Portorož, Slovenia Seasonal Site Non-seasonal Site Selected Sites Dry-Freeze Wet-Nonfreeze Dry-Nonfreeze Wet-Freeze

6. Portorož, Slovenia Diurnal Profiling Inertial Profiling Early AM Mid-AM Late AM - Early PM Evening Critical Passes!!

7. Portorož, Slovenia Outlines oCurl/Warp Measurement oProfile Synchronization and Joint ID o2GCI Curvature Index oRoCK System for Curvature- Impact-Roughess Analysis

8. Portorož, Slovenia Raw Profile IA_023A

9. Portorož, Slovenia Spike Profile Filter with moving average anti-smoothing Normalize by RMS Search deepest dip by a threshold

10. Portorož, Slovenia Spike Incidence Assemble the dip count across the data set

11. Portorož, Slovenia Weeded Spike Incidence Weed/clear false hits Extract the joint locations

12. Portorož, Slovenia Outlines oCurl/Warp Measurement oProfile Synchronization and Joint ID o2GCI Curvature Index oRoCK System for Curvature- Impact-Roughess Analysis

13. Portorož, Slovenia Westergaard Curling Formula

14. Portorož, Slovenia Adjusted Westergaard Curling Parameters oAdjusted to overcome Westergaard assumptions oFit to actual slab deformation oMore fundamental than an arbitrary geometric function oFitted parameters: Pseudo-radius of relative stiffness Pseudo-strain gradient

15. Portorož, Slovenia 2GCI Fit – Curled Down Slab 25-mm data

16. Portorož, Slovenia 2GCI Computation oIsolate the individual slab segments oDe-trend and de-mean the profile segment oMask joints oDefine model parameters oPerform nonlinear curve fitting

17. Portorož, Slovenia 2GCI Analysis AZ_001am - winter

18. Portorož, Slovenia 2GCI Analysis AZ_001am - winter

19. Portorož, Slovenia 2GCI Analysis MN_046a - summer

20. Portorož, Slovenia 2GCI Analysis MN_046a - summer

21. Portorož, Slovenia Mean Curvatures

22. Portorož, Slovenia Outlines oCurl/Warp Measurement oProfile Synchronization and Joint ID o2GCI Curvature Index oRoCK System for Curvature- Impact-Roughess Analysis

23. Portorož, Slovenia 2GCI vs Roughness AZ_001m

24. Portorož, Slovenia 2GCI vs Roughness AZ_001m

25. Portorož, Slovenia 2GCI vs Roughness AZ_001m

26. Portorož, Slovenia Roughness Curvature (downward) Curvature (upward) 0 CrtClf Rub Rlb Rzc The RoCK Chart

27. Portorož, Slovenia 0 R ub R lb R zc R btc Curvature-related Roughness Non Curvature-related Roughness Roughness Decomposition

28. Portorož, Slovenia Roughness Curvature (downward) Curvature (upward) 0 CrtClf Rub Rlb Rzc TYPE I-A Sites Curled up Curvature dominates roughness Src < 0 Rbtc > 0

29. Portorož, Slovenia Roughness Curvature (downward) Curvature (upward) 0 CrtClf Rub RlbRzc TYPE I-B Sites Curled up mildly Curvature affects roughness Src < 0 Rbtc ~ 0

30. Portorož, Slovenia Roughness Curvature (downward) Curvature (upward) 0 CrtClf Rub RlbRzc TYPE II Sites Curled up and down Curvature affects Roughness mildly Src < 0 Rbtc ~ 0 Src > 0 Rbtc ~ 0

31. Portorož, Slovenia Roughness Curvature (downward) Curvature (upward) 0 CrtClf Rub Rlb Rzc TYPE III-A Sites Curled down Curvature dominates roughness Src > 0 Rbtc > 0

32. Portorož, Slovenia Roughness Curvature (downward) Curvature (upward) 0 CrtClf Rub RlbRzc TYPE III-B Sites Curled down mildly Curvature affects roughness Src > 0 Rbtc ~ 0

33. Portorož, Slovenia Bolivian Project oTwo-lane undivided JCP oMountainous terrain with moderate fills and cuts o24-ft wide, 12-ft joint spacing o8-inch slab on 6-inch granular base oLocal climate is arid with rains from December to March oDrastic overnight temperature drops

34. Portorož, Slovenia Bolivian Project oLow relative humidity and extreme temperatures oMix with a relatively high water cement ratio, high CTE aggregate, and inadequate curing techniques. oLongitudinal cracks at the center of the slab in both travel directions after the first winter

35. Portorož, Slovenia Bolivian Project AM

36. Portorož, Slovenia Bolivian Project

37. Portorož, Slovenia Bolivian Project Strength FEM Analysis

38. Portorož, Slovenia The Implications… oWhat’s timing to measure roughness for a pavement acceptance testing? oWhat’s the best practice to avoid curl and warp? oWhat’s the best time to grind the pavements to improve smoothness?

39. Portorož, Slovenia Tools you can use… oNew, robust profile synchronization and joint identification techniques oInvention of 2GCI to better characterize slab curvature oNew, effective slab curvature analysis framework oRoCK System to assess curvature’s impact on roughness

40. Portorož, Slovenia Acknowledgement oUS FHWA Sponsorship oCo-authors: Steven M. Karamihas, University of Michigan, USA Robert Otto Rasmussen, P.E., Ph.D., The Transtec Group, Inc., USA David Merritt, P.E., M.S., The Transtec Group, Inc., USA Mark Swanlund, P.E., US DOT Federal Highway Administration, USA oMany US State DOT for assistance in field measurements