North Central Asphalt User Producer Group January 24, 2013 St. Louis, MO

Transcription

1 North Central Asphalt User Producer Group January 24, 2013 St. Louis, MO LABORATORY EVALUATION OF PPA MODIFIED BINDERS & MIXTURES IMPACT OF PPA MODIFICATION ON RUTTING AND MOISTURE SENSITIVITY by Gerald Reinke Doug Herlitzka Steve Engber Scott Veglahn John Jorgenson Dave Tranberg

2 SCOPE OF PRESENTATION 1. THIS PRESENTATION IS TO BE A SUMMARY OF THE BINDER AND MIXTURE TESTING PERFORMED IN PREPARTION FOR THE MNROAD TEST PROJECT TO EVALUATE PPA CONTAINING BINDERS? 2. ALSO TESTING OF THE FIELD MIXES AND BINDERS RECOVERED FROM THE FIELD MIXES IS DISCUSSED 3. THE MNROAD TEST PROJECT WAS DESIGNED TO SPECIFICALLY INVESTIGATE THE MOISTURE SENSITIVITY OF PPA CONTAINING BINDERS WHEN COMBINED WITH HYDRATED LIME AS AN ADDITIVE.

3 IN 2007 THERE WERE SOME VERY ENTRENCHED POSITIONS REGARDING THE USE OF PPA IN ASPHALT Quod enim mavult homo verum esse, id poitus credit What man wishes were true, he more readily believes.

4 CONTRIBUTORS 1. THE STUDY DESIGN CONSISTED OF 4 MIX TYPES a. PG PRODUCED WITH 2% KRATON 1184 CROSSLINKED b. PG PRODUCED WITH 0.75% PPA c. PG PRODUCED WITH 1% KRATON 1184 & 0.3% PPA d. PG PRODUCED WITH 1% ELVALOY AM & 0.3% PPA 2. MARATHON REFINING FROM ST. PAUL PARK, MN SUPPLIED THE PG BASE BINDER 3. KRATON POLYMERS SUPPLIED THE SBS & DUPONT SUPPLIED THE ELVALOY 4. INNOPHOS & ICL SUPPLIED THE PPA + SIGNIFICANT FUNDING 5. MTE PERFORMED THE FORMULATION AND TESTING OF BINDERS AND MIXTURES 6. MATHY S ASPHALT TERMINAL MADE THE BLENDS

5 BACKGROUND 1. In 2010 I co-authored a TRB paper with Darryl Fee, Rene Maldonado & Henry Romogosa of ICL 1 2. In part that paper dealt with research MTE conducted for ICL into the impact of PPA modified asphalt and PPA + polymer modified asphalt on mix performance a) MTE s work was conducted over the time period during which the MNRoad research was designed and conducted 3. Point was made that an estimated % of pavements in the previous 5 years contained PPA or million tons of mix. In the 3 years since 2010 This that discussion amount will has cover only increased data 4. Given these quantities if there related are wholesale to the MNROAD problems test with this additive shouldn t there be awareness project and of other them? PPA modified binder mixture laboratory results 1 Polyphosphoric Acid Modification of Asphalt, Fee, et al, TRB 2010

6 COMPARE MNROAD ACID STUDY RUT TEST WITH PG MADE WITH DIFFERENT FORMULATIONS TESTED IN PMW HAMBURG WET AT 50 C NO INNOVALT W ADDED TO ANY, HYDRATED LIME IN ALL 0 MNROAD ACID STUDY (0.75% PPA) 50 C AVERAGE BOTH WHEELS MNROAD ACID STUDY ELVALOY 50 C AVERAGE BOTH WHEELS MNROAD Acid Study Letdown (1% 1184, 0.3% 50 C AVERAGE BOTH WHEELS MNROAD Acid Study, (2% 50 C AVERAGE BOTH WHEELS RUT DEPTH IN mm Lab prepared mix with job aggregates using lab prepared binders, loose mix aged 2 hrs prior to compaction RUT CYCLES AT 50 C & 158 LBS (702 N) 03/31/08 22:46:21 C:\DRIVE_E\PMW 2007\MNROAD ACID STUDY\COMPARE RUT TEST MNROAD ACID STUDY C.spf

7 MNROAD ACID STUDY RUT TEST WITH PG BINDERS TESTED IN PMW HAMBURG WET AT 50 C WITH INNOVALT W 0 MNROAD Acid Study, (2% 50 C AVERAGE VOIDS 7.7%, GYRATIONS 33 MnRoad Acid ELVALOY+PPA +.5% Inn 50 C AVERAGE VOIDS 6.4%, GYRATIONS 67 MNRoad Acid, (1% 1184, 0.3%PPA,0.5% INN 50 C AVG VOIDS 6.5%, GYR 62 MNROAD Acid, PPA +0.5% Inovalt 50 C AVERAGE VOIDS 6.7%, GYRATIONS 42 RUT DEPTH IN mm Lab prepared mix with job aggregates using lab prepared binders, loose mix aged 2 hrs prior to compaction RUT CYCLES AT 50 C & 158 LBS (702 N) 03/31/08 22:52:26 C:\DRIVE_E\PMW 2007\MNROAD ACID STUDY\COMPARE ALL RUT TEST MNROAD Acid 50 C.spf

8 EVALUATION for INNOPHOS of PPA MODIFIED BINDERS MNROAD ACID STUDY TESTED IN PMW HAMBURG WET AT 50 C COMPARE ALL PG BINDERS 0-5 RUT DEPTH IN mm MN Road 50 C Wet AVERAGE BOTH WHEELS MN Road C Wet AVERAGE BOTH WHEELS MN Road Cell 34, C Wet AVERAGE BOTH WHEELS Mn Road Cell 77, Elvaloy & 50 C Wet AVERAGE BOTH WHEELS Field produced mix, reheated to 135 C prior to compaction So, what happened, why the difference? RUT CYCLES AT 50 C & 158 LBS (702 N) 04/02/08 08:29:34 C:\DRIVE_E\PMW 2008\MN ROAD PPA STUDY\COMPARE RUT TEST MN Road C Wet.spf

9 PG GRADE OF BINDERS AS SHIPPED BINDERGRADE PRODUCED TRUE PG GRADE PG SBS ONLY PG PG SBS + PPA PG PG PPA ONLY PG PG ELVALOY + PPA PG

10 PG GRADE OF BINDERS AS RECOVERED FROM FIELD MIX BINDERGRADE PRODUCED TRUE PG GRADE PG SBS ONLY PG PG SBS + PPA PG PG PPA ONLY PG PG PPA ONLY 2 nd sample PG PG ELVALOY + PPA PG NOTE: NO PAV AGING OF THESE BINDERS

11 PG GRADE OF BINDERS AS RECOVERED FROM FIELD MIX + PAV BINDERGRADE PRODUCED TRUE PG GRADE PG SBS ONLY PG PG SBS + PPA PG PG PPA ONLY PG PG ELVALOY + PPA PG PAV OF BINDER SHIPPED

12 EVALUATION for INNOPHOS of PPA MODIFIED BINDERS MNROAD ACID STUDY TESTED IN PMW HAMBURG WET AT 50 C COMPARE ALL PG BINDERS 0-5 RUT DEPTH IN mm MN Road 50 C Wet AVERAGE BOTH WHEELS MN Road C Wet AVERAGE BOTH WHEELS MN Road Cell 34, C Wet AVERAGE BOTH WHEELS Mn Road Cell 77, Elvaloy & 50 C Wet AVERAGE BOTH WHEELS Field produced mix, reheated to 135 C prior to compaction Basically due to excess rain the hot mix plant happened on at least 2 of the mixes RUT CYCLES AT 50 C & 158 LBS (702 N) 04/02/08 08:29:34 C:\DRIVE_E\PMW 2008\MN ROAD PPA STUDY\COMPARE RUT TEST MN Road C Wet.spf

13 C O M PA R E D R Y R U T T EST f or IN N O PH O S O F A LL PG BIN D ER S IN PM W H A M BU R G A T 5 8 C, 15 8 # LO A D COMPARE DRY HAMBURG RUT RESULTS FOR FIELD MIX SAMPLES OF ALL PG MIXES APPLIED AT MNROAD AT 58 C, 158 LB LOAD 0 MN Road Cell ( C AVERAGE BOTH WHEELS MN Road Field Mix, PPA 58.8 C AVERAGE BOTH WHEELS MN Road Cell C AVERAGE BOTH WHEELS Mn Road Cell C AVERAGE BOTH WHEELS - 5 RUT DEPTH IN mm These results are counter intuitive the reasons for which will become apparent as we proceed RUT CYCLES AT TARGET 58 C & 158 LBS (703 N) 04/02/08 08:32:54 C:\DRIVE_E\PMW 2008\MN ROAD PPA STUDY\COMPARE DRY RUT TEST MN Road ALL 58 C.spf

14 MSCR RESULTS OF RTFO RESIDUES & BINDER RECOVERED FROM FIELD MIX Keep in Jnr that % with very few BINDER exceptions % BINDER there are 58 C naturally RECOVERY occurring (RECOVERED PG s. 58 C RECOVERY (RTFO) We begin 3.2 kpa with PG kpa and FIELD alter MIX the 3.2 kpa temperature grade. If MSCR is 52 C % kpa recovery increases by approximately 20 PG percentage PG SBS SBS 1.27points for 19.3% each of the recovered binders PG PG SBS + SBS + PPA % PPA % PG PPA 2.0 3% PG ELVALOY + PPA PG PPA % PG ELVALOY + PPA

15 Rut wheel passes in Hamburg Rut Tester, 58 C, 158 lbs As a function of 3.2 kpa for RTFO residue RUT TEST PERFORMED ON FIELD MIX MATERIAL Rut_Depth_10000_wheel_passes_mm10.5 RUT DEPTH = F(Jnr of RTFO RESIDUE) Rank 4 Eqn 8002 Exponential(a,b,c) r 2 = DF Adj r 2 =0 FitStdErr= Fstat= a= b= c= Jnr_3200Pa(new system) RTFO residue Rut_Depth_10000_wheel_passes_mm

16 Rut wheel passes in Hamburg Rut Tester, 58 C, 158 lbs As a function of 3.2 kpa for recovered binder from mix RUT TEST PERFORMED ON FIELD MIX Rut_Depth_10000_wheel_passes_mm 10.5 C:\Program Files\TableCurve2Dv5.01\CLIPBRD.WK1 Rank 53 Eqn 8002 Exponential(a,b,c) r 2 = DF Adj r 2 = FitStdErr= Fstat= a= b= c= Jnr_3200Pa(new system) Recovered binder Rut_Depth_10000_wheel_passes_mm

17 CONCLUSIONS FOR MNROAD BINDERS AND MIXES 1. HYDRATED LIME IMPROVES THE MOISTURE SENSITIVITY OF ALL MIXES REGARDLESS OF THE USE OF ACID 2. PHOSPHATE ESTER ANTI-STRIP IN ADDITION TO HYDRATED LIME IMPROVED THE MOISTURE SENSITIVITY OF THE MNROAD MIX IN THE HAMBURG WHEN PPA WAS USED (FOR LAB SPECIMENS)

18 CONCLUSIONS FOR MNROAD BINDERS AND MIXES 3. AT LEAST THE PPA ONLY AND THE SBS + PPA MIXES APPEAR TO HAVE BEEN OVERHEATED BASED ON HAMBURG WET AND DRY RESULTS AND THE RECOVERED BINDER PROPERTIES 4. IT IS NOT YET EVIDENT WHETHER THIS OVERHEATING WILL IMPACT THE LONG TERM THERMAL CRACKING PERFORMANCE

19 THANK YOU FOR YOUR ATTENTION QUESTIONS COMMENTS

20 MOISTURE SENSITIVITY 1. IN A BINDER RHEOLOGY AND RUTTING STUDY-- WE LOOKED DRY AND WET HAMBURG RUTTING RESULTS ON SEVERAL MIXES 2. WET HAMBURG CONDUCTED ON 7 BINDERS (6 CONTAINED SOME LEVEL OF PPA) a. PPA ONLY BLENDS HAD 0.75% PPA b. POLYMER AND PPA BLENDS HAD 0.3% PPA 3. 3 AGGREGATE TYPES LIMESTONE, GRAVEL AND GRANITE 4. A 1 MILLION AND A 10 MILLION ESAL MIX FOR EACH AGGREGATE

21 ONSET OF STRIPPING FOR E-1 LIMESTONE, GRAVEL & GRANITE PPA PPA Elvaloy Elv SBS+ PPA SBS + PPA + phos ester + PPA Elv +PPA + PPA PPA PPA+ GRIPPER ELVALOY + PPA ELVALOY+PPA ELVALOY + PPA E-1 LIMESTONE E-1 GRAVEL E-1 GRANITE

22 ONSET OF STRIPPING E-10 LIMESTONE, GRAVEL & GRANITE PPA PPA PPA+ PPA ELVALOY Elvaloy ELVALOY Elv SBS + SBS+ PPA PPA + phos GRIPPER ester + PPA ELVALOY+PPA Elv +PPA PPA + PPA E-10 LIMESTONE E-10GRAVEL E-10 GRANITE

23 RUT PASSES TO 12.5 mm FOR E-1 LIMESTONE, GRAVEL & GRANITE PPA PPA+ PPA ELVALOY Elvaloy ELVALOY Elv SBS + SBS+ PPA PPA GRIPPER PPA ELVALOY+PPA PPA + phos ester + PPA Elv +PPA + PPA E-1 LIMESTONE E-1 GRAVEL E-1 GRANITE

24 RUT PASSES TO 12.5mm FOR E-10 LIMESTONE, GRAVEL & GRANITE PPA PPA PPA+ PPA ELVALOY Elvaloy ELVALOY Elv SBS + PPA SBS+ PPA GRIPPER PPA ELVALOY+PPA PPA + phos ester + PPA Elv +PPA + PPA E-10 LIMESTONE E-10 GRAVEL E-10 GRANITE

25 IMPACT OF PPA ON RECOVERED BINDER PROPERTIES IN THE FOLLOWING SLIDE DATA IS SHOWN OF BINDER RECOVERED FROM A STRIPPING PRONE MIX MIXES MADE WITH PG PRODUCED USING 0.75% PPA & A PG IN SOME CASES MIXES WERE TESTED THAT CONTAINED HYDRATED LIME (HL) AND SOME HAD NOT LIME SOME MIXES WERE MOISTURE SATURATED (BUT DRIED) PRIO TO EXTRACTION

26 DSR STIFFNESS OF PG (PPA MODIFIED BINDER) RECOVERED FROM TSR SPECIMENS DSR 70 C, kpa Orig DSR RTFO DSR SPEC TSR HL Soaked TSR HL Soaked TSR HL Dry TSR NO HL Soaked TSR NO HL Dry HAMBURG HAMBURG RUT PILL RUT PILL NO HL + HL

27 CONCLUSIONS FOR MOISTURE SENSITIVITY A. FOR ANY BINDER THERE IS A LEVEL OF PPA THAT IS TOO HIGH THAT WILL RESULT IN DECREASED MOISTURE RESISTANCE PERFORMANCE DATA NOT SHOWN BUT IS AVAILABLE + TERRY ARNOLD S WORK AT FHWA SHOWS SIMILAR RESULTS a. It seems preferable to me to limit the amount of PPA modification to 1 PG grade and set an upper limit on the amount of PPA that can be used. Some binders are just not suitable for PPA modification

28 CONCLUSIONS FOR MOISTURE SENSITIVITY 4. SOME BINDERS MODIFIED WITH PPA ONLY MIGHT EXPERIENCE A REDUCTION IN DSR STIFFNESS WHEN MIXED WITH HYDRATED LIME CONTAINING MIXES BASED ON EXTRACTED BINDER TESTS a. Lime may cause some reversal of PPA effect. b. Lime may retard binder aging c. Mixes should be tested for G* or E* properties to determine if adequate stiffness is present the extraction process itself may cause some of the loss of binder stiffness that we observe

29 CONCLUSIONS FOR MOISTURE SENSITIVITY PPA MODIFICATION BY ITSELF IS NOT THE EQUIVALENT TO POLYMER MODIFICATION IN TERMS OF RUTTING AND MOISTURE SENSITIVITY THE USE OF PPA IN CONJUNCTION WITH PPA RESULTS IN MIX PERFORMANCE THAT IS GENERALLY EQUAL TO OR BETTER THAN POLYMER ALONE (POLYMER & ASPHALT DEPENDENT)

30 FATIGUE 1. DSR TORSIONAL FATIGUE 2 WAS PERFORMED ON MIXES PRODUCED WITH % PPA ONLY AND PRODUCED WITH ELVALOY + 0.3% PPA 2. MIXES WERE TESTED UNAGED, AFTER 5 AND 10 DAYS OF AGING AT 85 C IN A FORCED DRAFT OVEN 2 The torsional fatigue test was developed by Joe Chevron in the 1980 s and reported in late 80 s & early 90 s in several AAPT papers by Goodrich and/or Ron Reese of Cal Trans

31 CYCLES TO 20 C COMPARISON OF FATIGUE FAILURE BETWEEN PG POLYMER MODIFIED AND PG ACID REACTED 1E+06 1E+05 1E+04 PG POLYMER MIX, UNAGED PG ACID REACTED MIX, UNAGED MICROSTRAIN 2000

32 CYCLES TO 20 C COMPARISON OF FATIGUE FAILURE BETWEEN PG POLYMER MODIFIED AND PG ACID REACTED 1E+06 1E+05 1E+04 PG POLYMER MIX, UNAGED PG ACID REACTED MIX, UNAGED PG POLYMER MIX, 5 DAY AGED PG ACID REACTED MIX, 5 DAY AGED MICROSTRAIN 2000

33 CYCLES TO 20 C COMPARISON OF FATIGUE FAILURE BETWEEN PG POLYMER MODIFIED AND PG ACID REACTED 1E+06 1E+05 1E+04 PG POLYMER MIX, UNAGED PG ACID REACTED MIX, UNAGED PG POLYMER MIX, 5 DAY AGED PG ACID REACTED MIX, 5 DAY AGED PG POLYMER MIX, 10 DAY AGED PG ACID REACTED MIX, 10 DAY AGED MICROSTRAIN 2000

34 FATIGUE CONCLUSIONS? 1. IT DOES APPEAR THAT MIXES PRODUCED WITH POLYMER HAVE BETTER FATIGUE PERFORMANCE THAN THOSE PRODUCED WITH JUST ACID 2. THIS NEEDS TO BE STUDIED IN MORE DEPTH DESPITE WHAT MANY WOULD SAY IS OBVIOUS

35 THANK YOU FOR YOUR ATTENTION QUESTIONS COMMENTS