The moisture susceptibility of a mixture is determined based on the combined effect of material properties as well as mixture properties.

Transcription

1 Asphalt Research Cnsrtium

2 Misture Damage Hypthesis The misture susceptibility f a mixture is determined based n the cmbined effect f material prperties as well as mixture prperties. Material prperties aging f binder ph f water surface energy interfacial adhesin; misture transprt interfacial adhesin interfacial adhesin Mastic & Mixture prperties vid structure misture transprt; pre pressure misture cntent mechanical prperties filler type & cntent mechanical prperties

3 Misture Damage Objectives Identify the mechanisms fr misture damage (Interactin f material mastic mixture prperties and its effect n misture damage) Understand relative cntributin f material and mixture prperties (Islate prperties that have significant effect n the prcess and are essential fr mdeling and predictin) Develp e and validate: tests t evaluate the misture susceptibility f mixes, and mdels t predict effect n perfrmance due t misture induced damage

4 Deliverables Misture Damage Imprved understanding f misture damage mechanisms Cmpnents f system t predict misture damage Tests fr mixture cmpnents Tests fr mixture Mdel t predict perfrmance Research and labratry prcedures Budget $ 4.99 M fr 5 years

5 Misture Damage Categry Specific Wrk Element Cnsrtium Partner WRI TTI UWM UNR AAT a) Affinity f asphalt t aggregate (test) X M1. Adhesin b) Wrk f adhesin X X c) Quantifying misture using DMA X a) Wrk f chesin (surface energy) X X M2. Chesin b) Impact f misture diffusin X c) Thin film rhelgy and chesin X M3. Aggregate a) Aggregate surface characterizatin X M4. Mdeling a) Develpment f mdel X M5. System a) Misture damage predictin system X X X X X

6 Misture Damage Wrk Elements Hypthesis 1a. Affinity f asphalt t aggregate (mechanical) 2c. Thin film rhelgy & chesin (mechanical) 3a. Aggregate characterizatin Explain interfacial behavir Cmpare Results Cmpare Results 1b. Wrk f adhesin (thermdynamic) 2a. Wrk f chesin (thermdynamic) Material prperties input 1c. Quantifying misture damage using DMA 2b. Impact f misture diffusin (mixture mastic interface) Mechanical prperties (mastic) input Kinetics related input 4a. Develpment f system and mdels fr predicting affect f misture damage n perfrmance

7 Fatigue Hypthesis Fatigue damage is a result f the grwth f small cracks and vids t frm larger cracks that result in damage. A unified mdel f fatigue damage based n sund principles i f mechanics must cnsider: adhesive and chesive bnd strengths in the cmpsite mixture viscelastic prperties micr damage fracture and flw impact f misture n mixture prperties ability f the mixture t heal and recver damage stress distributin within the mixture impact f aging n mixture prperties

8 Fatigue Objectives Develp a fundamental understanding f the material prperties and mechanics assciated with fatigue Develp an implementable unified fatigue damage mdel fr asphalt mixtures that integrates relevant factrs (chesive and adhesive bnd strengths, viscelastic and viscplastic prperties, aging etc.) Implement the unified fatigue damage mdel by integrating it int a numerical scheme t assess the fatigue behavir f mixtures under different labratry and field bundary cnditins Develp testing prtcls fr mdified and unmdified binders, mastic, mixture fr the unified mdel

9 Fatigue Deliverables Imprved understanding f fatigue damage and healing mechanisms Micrmechanics mdel t predict mixture behavir Unified fatigue damage mdel that can be implemented in structural design Structural mdel that incrprates unified fatigue damage mdel Test prtcls t determine prperties required fr the unified fatigue damage mdel Cmpnent selectin guidelines fr perpetual pavements based n the unified apprach Budget $ 5.52 M fr 5 years

10 Fatigue Categry F1. Material / Mixture Prperties F2. Test methd Develpme nt F3. Mdeling Specific Wrk Element Cnsrtium Partner WRI TTI UWM UNR AAT a) Chesive and adhesive prperties X b) Viscelastic prperties X c) Aging X d) Healing X a) Binder tests and effect f cmpsitin X b) Mastic testing prtcl X c) Mixture testing prtcl X d) Micrstructure characterizatin (X-Ray CT) X e) Verificatin (DSR vs. mixture fatigue) X X a) Asphalt micrstructure mdel X X X b) Micrmechanics mdel X c) Unified cntinuum fatigue mdel X d) Calibratin and validatin X X X

11 Fatigue Wrk Elements Hypthesis 1c. Aging Incrprate aging effect 1a. Chesive and Adhesive Prperties 1b. Viscelastic Prperties 1d. Healing Prperties Material Prperty Inputs 3c. Cntinuum fatigue mdel 3b. Micrmechanics mdel Mdels Cmpare results / prvide parameters Test Methds 2a. Binder test and effect f cmpsitin 2b. Mastic / FAM testing prtcl 2c. Mixture testing prtcl 2d. Micrstructure characterizatin (CT)

12 Hypthesis Engineered Materials 1. All materials f which asphalt cncrete is cmpsed have mechanical and gemetric prperties which may be cmbined, using micrmechanics, t btain the net prperties f the cmpsite materials 2. Using additives and/r new prductin prcesses, mdified asphalt binders and mixtures can be designed t deliver superir perfrmance that can tlerate extreme traffic and climatic cnditins 3. Using fundamental engineering principles in design f mixtures superir perfrmance can be achieved with using high cncentratin f recycled asphalt mixtures, emulsins, r warm mixture additives 4. Practical and effective prtcls fr testing and mdeling f such superir materials can be develped t prvide guidance fr selecting high perfrmance materials with predictable (less risky) perfrmance

13 Objectives Engineered Materials Develp analytical mdels fr the prperties f binders, mastic, and mixtures using the principles f mechanics Develp guidelines fr prducing and selecting engineered pavement materials fcused n limiting risk f pavement failures Develp guidelines fr high h level l use f recycled pavement mixtures, warm mixtures, and cld mixtures. Validate these guidelines using labratry damage resistance testing and field full scale trials.

14 Engineered Materials Deliverables Design mdels and guidelines fr cmpnents used in: RAP mixtures Warm mixtures Cld mixtures Thermal resistant mixtures Stable mixtures Budget $ 3.68 M fr 5 years

15 Engineered Materials Categry E1. Mdeling E2. Design Guidance Specific Wrk Element a) Analytical and micr-mechanics based mdels fr cmpsite mixture behavir Cnsrtium Partner WRI TTI UWM UNR AAT b) Damage resistance characterizatin fr binders X c) Warm mixtures X X a) Cmparisn f mdificatin techniques X b) Use f high percentage f RAP X X X X c) Critically designed HMA mixtures X d) Thermal cracking resistant t mixes X X fr intermuntain states e) Design f fatigue and rut resistant mixtures X X

16 Vehicle Pavement Interactin Gal Develp simplified tls t cmpute dynamic tire-pavement interactin fr special lading cnditins Use existing knwledge f macr and micr texture t design mixtures t enhance safety Objective Develp mdels t predict dynamic lads f mving vehicles and their effect n the respnse f flexible pavement Design surface curses t increase safety by increasing the fi frictin and r skid resistance

17 Vehicle Pavement Interactin Deliverables A near term cmputer mdel and database t estimate pavement respnses t dynamic lads fr user agencies Dynamic lad mdel and database t serve as input fr future integratin with cmprehensive pavement structural mdel Methd t estimate nise and frictin prperties f asphalt mixtures as a part f the mixture design prcess Budget $ 1.05 M fr 5 years

18 Vehicle Pavement Interactin Cnsrtium Partner Categry Specific Wrk Element WRI TTI UWM UNR AAT V1. a) Wrkshp n super single tires X Wrkshp V2. a) Mix design t enhance Design Guidance safety and reduce nise X V3. a) Pavement respnse mdel t X Mdeling dynamic lads

19 Validatin Gal Evaluate selected existing specificatins and validate research prducts frm this study under realistic lading and envirnmental cnditins encuntered in the field Objective Validate and refine research prducts using data frm validatin sites including MEPDG sites

20 Validatin Deliverables Cnstruct and mnitr cmparative pavement validatin sites n public highways in cperatin with State DOT s r at accelerated lading facilities Develp a materials reference library fr materials used in cmparative pavement sites in rder t supprt the research activities f the Cnsrtium and ther researchers Evaluatin f the MEPDG Asphalt Materials Mdels Imprved Superpave PG specificatins based n findings frm this research Budget $ 5.78 M fr 5 years

21 Validatin Categry Specific Wrk Element Cnsrtium Partner WRI TTI UWM UNR AAT V1. a) Mnitring f Warm Mix pavements X Field Validatin b) Cnstructin and mnitring f additinal pavement sectins V2. Accelerated Pavement Testing a) Third-Scale Mdel Mbile Lad Simulatr b) Cnstruct sectins at the Pecs RTC X X V3. R&D Applicatin a) Cntinual Assessment f Specificatins b) Validatin thrugh MEPDG sites and evaluatin f the MEPDG Asphalt Materials Mdels X X X

22 Technlgy Develpment Gal Develp implementable prducts frm this and ther related research Objective Begin refining selected prducts frm the Fatigue, Misture Damage, Engineered Pavement Materials, and Vehicle Pavement Interactin ti research prgrams int useful tls fr engineers and technlgists invlved in the design, cnstructin, and maintenance f asphalt pavement systems.

23 Technlgy Develpment Deliverables New r imprved standard test methds prpsed specificatin type guidelines mdels fr materials and pavements Specific design guidance fr imprving the perfrmance f flexible pavements. Budget $ 3.94 M fr 5 years

24 Technlgy Develpment Categry TD. Technlgy Develpme nt Specific Wrk Element 1) Priritize and select prducts fr early develpment 2) Develp early prducts 3) Identify prducts fr mid-term and lng-term develpments Cnsrtium Partner WRI TTI UWM UNR AAT X X 4) Develp mid-term and lngterm prducts X

25 Technlgy Transfer Categry Specific Wrk Element Cnsrtium Partner WRI TTI UWM UNR AAT TT1. Technlgy Transfer a) Cnsrtium web site X b) Cmmunicatins X c) Presentatins and publicatins X X X X X d) Materials database X e) Research database X