The results are presented of a laboratory study on the stiffness of bituminous mixes determined by the Indirect Tensile Method, according to the EN 12697-26 Annex C standard. The testing, at the Experimental Road Laboratory of the University of Padova, was performed by means of the Nottingham Asphalt Tester, on high-performance bituminous mixtures, comprising high modulus mixes, stone mastic asphalt and porous asphalt. The purpose was to check the applicability of the above-mentioned standard to both dense graded as well as porous asphalt mixtures, at various temperatures, strain levels and rise times, and to compare the controlled strain with the controlled stress loading procedure, the latter not being included in the Annex C of the standard. The influence of other two important variables, i.e. the number of diameters across which the specimen is to be tested and the number of conditioning impulses before the test, have been evaluated and quantified. The results of this study demonstrate that the standard controlled strain loading procedure could have selective applicability depending on the mix being studied and testing temperatures. The controlled stress loading procedure results are necessary to evaluate the stiffness at extremely low and high testing temperatures and loading frequencies.

Critical Analysis of the EN 12697-26 Standard for the Determination of the Indirect Tensile Stiffness Modulus

PASETTO, MARCO;
2006

Abstract

The results are presented of a laboratory study on the stiffness of bituminous mixes determined by the Indirect Tensile Method, according to the EN 12697-26 Annex C standard. The testing, at the Experimental Road Laboratory of the University of Padova, was performed by means of the Nottingham Asphalt Tester, on high-performance bituminous mixtures, comprising high modulus mixes, stone mastic asphalt and porous asphalt. The purpose was to check the applicability of the above-mentioned standard to both dense graded as well as porous asphalt mixtures, at various temperatures, strain levels and rise times, and to compare the controlled strain with the controlled stress loading procedure, the latter not being included in the Annex C of the standard. The influence of other two important variables, i.e. the number of diameters across which the specimen is to be tested and the number of conditioning impulses before the test, have been evaluated and quantified. The results of this study demonstrate that the standard controlled strain loading procedure could have selective applicability depending on the mix being studied and testing temperatures. The controlled stress loading procedure results are necessary to evaluate the stiffness at extremely low and high testing temperatures and loading frequencies.
2006
9782550490098
File in questo prodotto:
Non ci sono file associati a questo prodotto.
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11577/1557549
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact