Transcript Investigation of rrheologi
EUROMAT 2005 CONFERENCE PRAGUE
Reological Model and Reological Properties of Asphalt Mixtures
L. A. Gömze and A. Kovacs University of Miskolc, (Hungary) [email protected]
Tel: +36-30-7462714 - Fax: +36-46-565103
EUROMAT 2005 CONFERENCE PRAGUE
Subjects
Characterization of Burgers reological model Introduction of combined reo-tribometre instrument Review of shearing tests Review of relaxation tests Determination of mechanical static yield-point of asphalt mixtures Conclusion L. A. Gömze and A. Kovacs University of Miskolc, (Hungary) [email protected]
Tel: +36-30-7462714 - Fax: +36-46-565103
EUROMAT 2005 CONFERENCE PRAGUE
Reological Model of Burgers Materials
Till today asphalt mixtures were characterised by reological model of Burgers Using Bourgers reological model means asphalt mixtures will endure non reversebile deformations as: m(t)= t/ 1 in each cases, when affected on it pressure stress >0 L. A. Gömze and A. Kovacs University of Miskolc, (Hungary) [email protected]
Tel: +36-30-7462714 - Fax: +36-46-565103
EUROMAT 2005 CONFERENCE PRAGUE
Combined Reo-tribometre Instrument
1.table; 2. worm-gear; 3. electromotor; 4. cable-drum; 5. cable-way or ropeway; 6. Moveable car with shearing plate; 7. inductive meassurer of moving; 8. force meassurer; 9. heatable speciment-fixture; 10. pneumatic cylinder; 11. magnetic valve; 12. meassurer of pressure; 13. compressor; 14. termostate; 15. control panel; 16. spider; 17. computer L. A. Gömze and A. Kovacs University of Miskolc, (Hungary) [email protected]
Tel: +36-30-7462714 - Fax: +36-46-565103
EUROMAT 2005 CONFERENCE PRAGUE
Photo of Combined Reo-tribometre Instrument
L. A. Gömze and A. Kovacs University of Miskolc, (Hungary) [email protected]
Tel: +36-30-7462714 - Fax: +36-46-565103
EUROMAT 2005 CONFERENCE PRAGUE Tipical Shearing-force Deformation/displancement Diagrammes, Measured on Marshall-Probes
1200 -50 1000 800 600 400 200 0 0 -200 50 100 150 200 250
100 fok 110fok Elmozdulás [mm] 120 fok, 130fok 140 fok
L. A. Gömze and A. Kovacs University of Miskolc, (Hungary) [email protected]
Tel: +36-30-7462714 - Fax: +36-46-565103
EUROMAT 2005 CONFERENCE PRAGUE
Some Resultes of Shearing Tests
Effective viscosity of asphalt mixtures can be determined as: e = (H/v); [MPa s] T [°C] 100 110 120 130 F max [N] 974 952 845 810 max [MPa] 0,1192 0,1165 0,1034 0,0991 e [MPa s] 0,216 0,198 0,136 0,119 F dny [N] 348 294 284 262 dny [Mpa] 0,0426 0,0359 0,0348 0,0321 d [MPa s] 0,0232 0,0191 0,0128 0,0074 140 775 0,0945 0,106 217 0,0265 0,0053 L. A. Gömze and A. Kovacs University of Miskolc, (Hungary) [email protected]
Tel: +36-30-7462714 - Fax: +36-46-565103
EUROMAT 2005 CONFERENCE PRAGUE
Relaxation Test of Asphalt Mixtures on Combined Reotribometre
F 1 =var – shearing force [N] P ny =F 2 /A=var – pressure stress in body [MPa] A=const . – working surface of Marshall-probe; [mm2] Q=var – Materials in asphalt mixture T=const – temperature of asphalt mixture [°C] L. A. Gömze and A. Kovacs University of Miskolc, (Hungary) [email protected]
Tel: +36-30-7462714 - Fax: +36-46-565103
EUROMAT 2005 CONFERENCE PRAGUE
Tipical Specific Deformation-Time Functions of Asphalt Mixtures
L. A. Gömze and A. Kovacs University of Miskolc, (Hungary) [email protected]
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EUROMAT 2005 CONFERENCE PRAGUE
Rheological Model of Asphalt Mixtures made with Bitumen Binders
E 1 E Kelvin body plastic body r pl k 2 0 1 2 – Hookean dinamic modulus – Elasticity modulus of Voigt – Static liquid limit of the visco – – Viscoity of the plastic-viscose – Viscosity of the – actual elastic deformation plasticy-viscous delayed elastic Voigt-Kelvin’s deformation deformation L. A. Gömze and A. Kovacs University of Miskolc, (Hungary) [email protected]
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EUROMAT 2005 CONFERENCE PRAGUE
Effective Viscosity of Shattered and non-shattered material Structures
0 t r First derive of specific deformation by time; - Second derive of specific deformation by time; – Static yield-point of the material strucure/systeme ; [MPa] – Time of delay of elastic deformation in the material structure/systeme of asphalt mixtures; [s] t fr – Time intervall of relaxation of mechanical stress in L. A. Gömze and A. Kovacs University of Miskolc, (Hungary) [email protected]
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EUROMAT 2005 CONFERENCE PRAGUE
Tipical Relaxation Curve of Shearing Stress in Asphalte Mixtures at Shearing Force 100 N
Relaxáció100 N 0,01 0,008 0,006 0,004 0,002 0 -0,002 0 500 idő (s) 1000 1500 2000 L. A. Gömze and A. Kovacs University of Miskolc, (Hungary) [email protected]
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EUROMAT 2005 CONFERENCE PRAGUE
Effective Viscosity as Funktion of Shearing Stress
0,09 0,08 0,07 0,06 0,05 0,04 0,03 0,02 0,01 0 0 0,0122238; 0,031876 0,018357; 0,0201311 0,030595; 0,043722 0,042833; 0,0383164 0,024476; 0,018608 0,036714; 0,030067 0,048952; 0,076223 0,01 0,02 0,03 0,04
Nyírófeszültség [MPa]
0,05 0,06 L. A. Gömze and A. Kovacs University of Miskolc, (Hungary) [email protected]
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EUROMAT 2005 CONFERENCE PRAGUE
Static Yield-point of Asphalt Mixture
Up to 75 N-there is no deformation = 0,009178 [MPa] Between 75 N-95 N there is an elastic deformation Over 95 N- there is a residual deformation in the examined asphalt mixture = 0,010402 [MPa] L. A. Gömze and A. Kovacs University of Miskolc, (Hungary) [email protected]
Tel: +36-30-7462714 - Fax: +36-46-565103
EUROMAT 2005 CONFERENCE PRAGUE
Conclusion
Using the new reo-tribometre patented by Dr. Gömze we could develop a new reological model for asphalt mixtures and determine the values of their mechanical and reological characteristics and coefficiences like E, , ...
The new reological model can be used by the engineers of road-building industry in wide range in development of asphalt mixtures with different microstructural and mechanical, reological properties.
L. A. Gömze and A. Kovacs University of Miskolc, (Hungary) [email protected]
Tel: +36-30-7462714 - Fax: +36-46-565103
EUROMAT 2005 CONFERENCE PRAGUE
Conclusion Conclusion
Using the new reological model of asphalt mixture developed by authors, engineers can determine the maximum values of shearing stresses, which asphalt roads can endure (wear out) without demages.
Using the new reological model and meassured mechanical and reological coeffitiences engineers can determine the values of mechanical stresses, affect on surfaces of concrete and stone particles of roads throught the asphalt mixtures.
L. A. Gömze and A. Kovacs University of Miskolc, (Hungary) [email protected]
Tel: +36-30-7462714 - Fax: +36-46-565103
EUROMAT 2005 CONFERENCE PRAGUE
Conclusion
Determining the values of statistic yield-points of different asphalt mixtures on the combined reotribometre, the authors could contravene the statement that asphalt mixtures made with bitumen binders, generaly loss their strength when their temperature higher than 25 °C .
The authors have find that high values of effective viscosity of asphalt mixtures during their spreading and rollering are the causes of shortages of macrostructure, density and mechanical strength of asphalt roads in several times.
L. A. Gömze and A. Kovacs University of Miskolc, (Hungary) [email protected]
Tel: +36-30-7462714 - Fax: +36-46-565103
EUROMAT 2005 CONFERENCE PRAGUE
THANK YOU FOR YOUR ATTENTION
L. A. Gömze and A. Kovacs University of Miskolc, (Hungary) [email protected]
Tel: +36-30-7462714 - Fax: +36-46-565103