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Highlights: [•] Two tests were applied to evaluate fracture properties of asphalt mixtures. [•] Fénix test and semi-circular bending test. [•] The loading rate and the temperature influence on mixtures were analyzed. [•] The Fénix test is more adequate for high temperatures while the SCB is better at low temperatures. [•] At low temperatures asphalt mixture present an extremely stiff behavior. [ABSTRACT FROM AUTHOR]

Highlights: [•] Fénix is a new monotonic test to assess fracture energy during cracking of bituminous mixtures. [•] EBADE is a new strain sweep test to evaluate fatigue resistance of bituminous mixes. [•] Failure Strain is defined from dissipated energy density obtained through EBADE test. [•] Variation of mechanical behaviour with temperature has been analyzed. [•] Master curve that provides information about mixture response has been defined. [•] Mixture properties at low temperatures must be considered during design phase. [ABSTRACT FROM AUTHOR]

Fatigue is associated with the deterioration caused by applying repeated loads, and is affected by temperature or aging. Generally, time sweep tests are used to simulate fatigue, in order to obtain the fatigue laws. However, this requires too much time, often preventing its use. A method to estimate the fatigue laws from a strain sweep test is presented. The test was performed on a semi-dense mixture with different types of binder (unconditioned or aged) tested at different temperatures. This test is able to estimate fatigue laws more quickly, allowing the effect of different factors on the mixtures' fatigue life to be studied. [ABSTRACT FROM AUTHOR]

One of the basic assumptions of analytical dimensioning models of asphalt pavements is failure due to fatigue cracking of the bituminous layers. Furthermore, it is considered that the damaging effects of different traffic loads are linear and cumulative, per Miner's law. However, the analysis carried out on the effect of temperature, rest periods, and ageing of the bituminous materials questions considering fatigue failure as the only and main assumption for the calculation of the pavement life. Ageing of the pavement asphalt layers results in stiffening and transverse cracking. Consequently, these asphalt layers are no longer of infinite extent in the horizontal direction and their response resembles that of a slab. The application of this last calculation assumption provides pavement sections more in line with those used in Spain in the Catalogue of Structural Sections, which is based on experience gained from the real behavior of those sections. The calculation based on the fatigue laws results in undersized structures. This paper shows the results of a strain sweep test implemented at the UPC Roads Laboratory, which was used to analyse all the aforementioned effects and to propose a calculation procedure for heavy traffic pavements considering transverse cracking of the asphalt layers. [ABSTRACT FROM AUTHOR]

Abstract: Fatigue is one of the most common causes of damage in bituminous pavements. However, since fatigue characterization requires complex cyclic tests, this property is not usually taken into account when designing bituminous mixtures. The present study introduces a new methodology to assess fatigue behavior of bituminous mixtures by means of a simpler procedure based on a new fracture test called Fénix. Several bituminous mixtures were tested at the Road Research Laboratory of the Technical University of Catalonia using the Fénix test and the three-point bending beam fatigue test, which complies with the new European standard UNE-EN 12697-24:2006. Results show that this new methodology assesses fatigue behavior of bituminous mixes by correlations between both tests. In addition, the procedure can be used to relate stiffness and dissipated energy parameters obtained in the cracking process, which allows the choice of mixtures with better fatigue performance considering the thermal conditions to which mixtures will be subjected during their service life. [Copyright &y& Elsevier]

The role of the filler in asphalt mixtures is particularly important because of its influence on mastic behaviour. The filler improves the resistance properties of bitumen against the action of traffic loads and temperature. However, the filler can also adversely affect bitumen in mastics excessively brittle and stiff due to inappropriate design. For these reasons, it is interesting to investigate the effect of filler type and content on mastic composition. This paper presents results from a strain sweep test applied to bituminous mastics prepared with different filler types and contents at several temperatures. The obtained stiffness modulus and failure strain results provide information to assess the fatigue behaviour of the analysed mastics. [ABSTRACT FROM AUTHOR]

Highlights: [•] Fénix test allows assessing fracture energy during cracking of bituminous mixtures. [•] Variation of mechanical behavior with temperature has been analyzed. [•] Several types of bituminous mixtures with a wide stiffness range were studied. [•] Mixture with high performance polymer modified bitumen showed the best response to cracking. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents an experimental study to characterize the mechanical behaviour of bituminous mixtures containing high rates of reclaimed asphalt pavement (RAP). Two semi-dense mixtures of 12 and 20mm maximum aggregate size and containing 40% and 60% RAP, respectively (S-12 and S-20, in accordance with Spanish specifications), which were used for rehabilitation of a highway section, were evaluated. First, the effect of RAP variability on the recycled mixtures was analyzed. Their mechanical properties were then studied by determining the stiffness modulus and indirect tensile strength and cracking and fatigue behaviour. Results show that high rates of recycled material can generally be incorporated into bituminous mixes by proper characterization and handling of RAP stockpiles. [Copyright &y& Elsevier]