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  • The results in the spreadsheet can be

    2018-10-25

    The results in the spreadsheet can be reproduced by downloading PeakFit (PF) at https://www.ncnr.nist.gov/instruments/bt8/PF.zip and pasting the spreadsheet contents into the stress calculation worksheet. When doing this, ׳D0׳ should be a fixed parameter, all other stresses should be “free” or unchecked. There are comment boxes in the Excel sheet providing instructions.
    Disclaimer
    Acknowledgements This work was supported by the National Science Foundation under Grant #1657195. We acknowledge the support of the National Institute of Standards and Technology, U.S. Department of Commerce, in providing the neutron research facilities used in this work.
    Data This article describes the average output polarization (AOP) for basic reversible logic gates of Double Feynman, Toffoli, TR, R, NG, SCL and BVF gates at different temperature levels are shown in Table 1.
    Experimental design, materials and methods
    Data The dataset within this article provides averaged values of ultrasonic pulse transit time and velocity measurements (Table 3) and transmission ratios (Table 4) on prismatic laboratory samples of different bituminous mixtures: semi-dense asphalt concrete (AC-S), gap-graded asphalt concrete for very thin layers (AC-TL, also known in Europe as BBTM) and porous asphalt (PA). All of these materials are commonly used in surface layers of asphalt pavements. By means of regression analysis, the aforementioned data was used to calibrate an analytical model in order to determine the depth of a surface-breaking crack on asphalt pavements using ultrasounds (Eq. 6).
    Materials Slab specimens (300×300×60mm) of 3 different types of hot mix asphalt (HMA) were prepared: a) semi-dense asphalt concrete (AC 16 surf 50/70S); b) gap-graded asphalt concrete for very thin layers (BBTM 11B PMB 25/55–65); c) porous asphalt mixture (PA 11 PMB 25/55–65). Given that ultrasonic techniques are non-destructive, these specimens were subsequently used to monitor the self-healing and the CMX001 of the crack depth after repeated heating cycles applying microwaves (see Ref. [1]). For this reason, a steel filing with corumdum powder of size less than 0.063mm (90% steel / 10% corumdum, approximately, obtained from radial saw grindings) was used to substitute the mineral filler (metallic filler). The three different aforementioned asphalt mixtures were produced following the Spanish road specifications (PG-3) [2] (in particular, aggregate gradation for each type of mixture, minimum bitumen content and air void content) and compacted by rolling according to EN 12697-33. The main properties of the mixtures and the component materials are summarized in Table 1. Additional characterization properties of the mixtures can be seen in Ref. [1].
    Instruments The ultrasonic device was a CSI type CCT-4 “concrete tester” (resolution ±0.1µs) with cylindrical couplant plate contact (CPC) piezoelectric transducers of 26mm diameter and 54kHz. Despite the fact that high-frequency ultrasounds present better beam directivity, defined onset, sensitivity and lateral resolution characteristics, high energy pulses and relatively low excitation frequencies are necessary when working with bituminous mixtures (inhomogeneous and viscoelastic materials) due to the high wave attenuation caused by absorptive and scattering phenomena as well as to the limited size of the aggregates and cracks being investigated. Ultrasonic testing on Portland cement concrete, for instance, is usually restricted to frequencies of less than 150kHz [3] to avoid considerable levels of coherent (microstructure) noise. The frequencies employed during ultrasonic testing should decrease as crack depth and temperature increase to compensate for elastodynamic wave scattering. According to the experience obtained from data in Ref. [1], working frequencies for bituminous mixtures should be less than 70kHz, recommending if possible transducers with a frequency between 24 and 54kHz, being low frequencies more suitable for very long path lengths and greater maximum size of aggregate.