Rutting and Fatigue Resistance of
Asphalt Mix tures Using
Incremental Repeated
Load Permanent
Deformation (iRLPD)
AA SHTO Designation: TP 116- 20 (2021) 1
Technically R evised: 2020 R eviewed but Not Updat ed: 2021 Editorially R ev ised: 2021
Technical Subcommit tee: 2d, Proportioning
of A sphalt–A ggregate Mix tures
A merican A ssociat ion of St at e Highway and Transport at ion Officials
555 12 th
St reet NW , Suit e 1000
TS-2d TP 116-1 AA SHTO
Rutting and Fatigue Resistance of Asphalt
Mix tures Using Incremental Repeated
Load Permanent Deformation (iRLPD)
A A SHTO Designat ion: TP 116- 20 (2021) 1
Technically R evised: 2020 R eviewed but Not Updat ed: 2021 Editorially R ev ised: 2021
Technical Subcommit t ee: 2d, Proport ioning of A sphalt – A ggregat e Mix t ures
1. SCOPE
1.1. Th is stan dard describes a test meth od for mea su rin g th e resista n ce ofasph alt mix tu res to ru ttin g
a n d fa tigu e crackin g u sing min imu m stra in rates (m*) from an in cremen ta l repeated l oa d
perma n en t deforma tion (iRLPD) test cond ucted by mea n s ofa dy n a mic testin g system (DTS).
Th is pra ctice is in tend ed for den se- a n d gap-graded mix tu res w ith n omin a l ma x imu m a ggrega te
sizes to 37.5 m m.
1.2. Thi s standard may i nvolv e hazardous mate ri als, operati ons, and e quipme nt. Thi s standard doe s
not purport to address all ofthe safe ty concerns associ ated w i th i ts use .It is the re sponsi bi li ty of
the use r ofthi s procedure to establi sh appropri ate safe ty and he alth practi ce s and to de termi ne
the appli cabi li ty ofre gulatory li mi tati ons prior to i ts use .
1.3. The quali ty ofthe re sults produced by thi s standard are de pe nde nt on the compe tence ofthe
personne l performing the procedure and the capabi li ty , cali brati on, and mainte nance ofthe
equipme nt use d. Age nci es that meet the cri teri a ofR 18 are gene rally considere d c apable of
competent and objecti v e testi ng/sampling/i nspecti on/etc. Users ofthi s standard are cauti one d that
compli ance w i th R 18 alone does not comple tely assure reli able results. Reli able re sults depe nd
on many factors; follow ing the sugge sti ons ofR 18 or some si mi lar acceptable gui deli ne prov i des
a means ofe valuati ng and controlli ng some ofthose factors.
2. R EFER ENCED DOCUMENTS
2.1. AASHTO Standards:
R 18, Esta blish in g a nd Implem en tin g a Qu ality Man agemen t System for Con stru ction
Ma terials Testin g Laboratories
R 29, G rading or Verify ing th e Performa nce Grade (PG ) ofa n A sph a lt Binder
R 30, Mixtu re Con dition in g ofHot Mix Asph a lt (HMA )
R 83, Prepara tion ofCy lin drical Performa n ce Test Specimen s Usin g th e Su perpa v e G y ratory
Compactor (SGC)
T 312, Prepa ri n g a nd Determin in g th e Den sity ofA sph a lt Mix tu re Specimen s by Means ofth e
Su perpave G y ra tory Compactor
T 378, Determin ing th e Dyn amic Modu l u s an d Flow N u mber for A sph a lt Mixtu res Using th e
Asph alt Mixture Performa n ce Tester (AMPT)
© 2021 by t h e A m erica n A ssocia t ion of St a te High w a y a n d Tra n sport a tion Officia ls.
TS-2d TP 116-2 AASHTO
TRB. Equ ipmen t Specifica tion for th e Simple Performan ce Test System, Version 3.0. In
Appen dix F of Nati onal Cooperati v e Highway Rese arc h Report 629 : Ruggedne ss Testi ng of
the Dynami c Modulus and Flow Numbe r Tests w i th the Simple Performance Te ster. Na tion a l
Coopera tive High w a y Research Progra m, Tran sportation Research Board, W ash ington , DC,
2008.
3. TERMINOLOGY
3.1. De fi ni ti ons:
3.1.1. confi ning pre ssure—stress applied to a ll su rfa ces in a con fin ed test.
3.1.2. contact stre ss—th e consta n t a xial stress applied to h ol d th e specimen in pla ce.
3.1.3. dev i ator stre ss—differen ce betw een th e tota l a xial stress a nd th e con fin ing pressu re in a
confin ed test.loadi ng incre ment—500 cycles ofa repea ted load .
3.1.4. loadi ng i nc rement—500 cycles ofa repeated loa d in th e ru ttin g test and 100 cycles ofa repeated
load in th e fa tigu e test.
3.1.5. mi ni mum strai n rate (m* )—th e low est perman en t stra in per cycle in a loadin g in cremen t, w h ich is
th e perma n en t stra in du e to th e last cy cle ofa loa d in g in cremen t.
3.1.6. permane nt deformati on on -recov ered d eformat ion in a repeated load test.
3.1.7. repe ate d load cy cle —loa din g of0.1 s foll ow ed by 0.9-s rest period .
3.1.8. secondary stage —th e load in g cy cles w h ere th e perma n en t axia l stra in rate is sta ble.
3.1.9. strai n rate—th e perma n en t a x ia l stra in du e to on e repeated loa d cy cle.
3.1.10. strai n acce lerati on—th e rate ofch ange ofth e strain ra te.
4. SUMMA R Y OF THE TEST METHOD
4.1. Th is test meth od describes procedures for evalu a ting resista n ce ofasph a lt m ix tu res to ru ttin g an d
fatigu e cra cking by mea su ring th e min imu m stra in ra te (m*)at th e critica l tempera tu re an d va ri ou s
load lev els u sin g th e iRLPD meth od .
4.2. Th e iRLPD test is con du cted at on e test tem pera tu re an d in severa l in cremen ts. Th e d eviator l oa d
is h eld con stan t d urin g ea ch in cremen t an d is in creased for ea ch subsequ en t in cremen t. Th e load
pu lse is 0.1 s every 1.0 s. Perm an en t axia l strain s du e to each load cycle (perma n en t strain ra te) a re
measu red by th e actu ator. Th e min imu m stra in ra te for ea ch in cremen t is d efin ed a s th e perm an en t
axia l stra in du e to th e last cy cle.
4.3. Th ere a re tw o meth od s ofcon du cting th e ruttin g test.
4.3.1. Meth od A is condu cted on a 150-mm (6.0-i n ) d iameter by 115-mm (4.5-i n .) h igh v ol u metric
specimen w ith ou t applyin g con fin emen t, in on e in cremen t of500 cycles.
4.3.2. Meth od B is con du cted on a 100-mm (4.0-in .) diameter by 150-mm (6.0-in .) h igh cylin d er w ith
69-kPa (10-psi) confin emen t, in fou r in cremen ts of500 cy cles each .
© 2021 by t h e A m erica n A ssocia t ion of St a te High w a y a n d Tra n sport a tion Officia ls.
