Determining The Elongation Energy Of PmB At Various Extension Lengths

Abstract

The topic of the work is evaluation of standardized method for determining force in ductility measurement according to the standard EN 13589. Standard EN 13589 specifies a method for determining the tensile properties of bituminous binders, in particular those of polymer-modified bitumens by means of a force ductility test. A molded test specimen is extended in ductilometer at the test temperature and at constant speed until fracture or an elongation of at least 1333 % (400 mm) is achieved. Standard EN 13703 specifies a method for determining energy of bituminous binders from tensile characteristics. During the standardized test, the force and elongation are recorded, and the deformation energy is calculated. The deformation energy (Ei) is determined from the recordings of the tensile curves. Conventional energy (E*i) is obtained as a quotient of the deformation energy and the initial cross-area of the test specimens. The main results of the investigation are the readings of the energy consumed up to an elongation of 0.2 m (E'0.2) and 0.4 m (E'0.4). The final result of the investigation is the difference between the readings of the measured energy, i.e. E's = E'0.4 - E'0.2 = E*0.2-0.4.
The main objective of the work was to investigate whether the energy E's, as defined according to the draft standard prEN 13589: 2016, is in correlation with the results of other properties of bitumen. Estimates of the achieved correlation were also performed in the case when the elongation lengths were different from those defined in the standard. Three different test temperatures were used 5°C, 10°C and 25°C. In the work it was also investigated whether the requirements in these standards are applicable to all polymer bitumen types PmB 45/80-65 available on Slovenian market.