8 research outputs found

    Effects of reclaimed asphalt and warm mix asphalt on the availability of the road network

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    This repot reviews the EARN project, which was undertaken under CEDR Call2012 in order to investigate the effects of using reclaimed asphalt (RA) and/or lower temperature asphalt on the road network. The work consisted of a review of existing data on service lifetime and availability of road materials and structures, a site trial to evaluate varying proportions of RA, experimental evaluation of moisture damage and ageing in asphalt mixtures and development of an impact assessment model. The site trial involved four different mixtures containing varying proportions of RA and warm mix additive and was monitored for international roughness index, mean profile depth, corrected SCRIM Coefficient, indirect stiffness modulus, water sensitivity and indirect tensile strength, the latter with and without artificial ageing. The monitoring was extended to 40 months with two extensions to the project, when monitoring of the binder mechanical and other properties were also made.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Pavement Engineerin

    Effect of using of reclaimed asphalt and/or lower temperature asphalt on the availability of the road network

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    The use of reclaimed asphalt, secondary component materials and/or additives and lower temperature asphalt are being increasingly used in order to improve the sustainability of asphalt production. The use of reclaimed asphalt reduces the need for virgin materials whilst lower temperature asphalts have reduced CO2 emissions, increased sustainability, improved working conditions for construction and maintenance crews, reduced noise level on the work sites, extended paving season and provided financial benefits from lower production and transport costs. However, there is uncertainty about the ageing and durability performance of these technologies because there is limited information available on their long-term performance. Changes in durability will affect the availability of the road network for highway authorities. CEDR commissioned a European project to assess these uncertainties. A site trial was commissioned on one of the Irelands busiest motorways (M3), comprising stone mastic asphalt mixtures containing varying proportions of the reclaimed asphalt with some using warm mix technology. The site has been monitored regularly over a full calendar year for the material performance. A suite of laboratory tests have been undertaken concentrating on the combined effect of ageing and moisture damage on the performance of asphalt mixtures on the site trial. The findings have been used to develop life-cycle analysis models to customise them for the effect of using alternative component materials on the availability of the network and their overall financial and environmental cost, both initial and whole-life. The costs identified are both direct (of the construction and maintenance) and indirect (on society in general, such as congestion). The paper describes the model and the assurance that can be given to the assumptions made within the model from the research findings. Comparative sensibility studies are included.Structural EngineeringCivil Engineering and Geoscience

    Effect of using of reclaimed asphalt and/or lower temperature asphalt on the availability of the road network

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    There is a need for a method for assessing the results from changes in the potential durability of road materials due to the inclusion of reclaimed and secondary component materials in the manufacture of new road materials. Such changes will have an effect on the cost of the construction maintenance, both financially to the client and environmentally to society in general, and any savings may be transitory. A site trial has been laid of mixtures with and without reclaimed asphalt and work started to assess their durability from early-life properties. The trials are being monitored for their initial performance whilstlaboratory trials are concentrating on the combined effect of ageing and moisture damage on the performance of asphalt mixtures on the trial. All three strands are being used to develop life-cycle analysis models to customise them for the effect of using alternative component materials on the availability of the network and their overall financial and environmental cost, both initial and whole-life. The costs will be identified as being direct (of the construction and maintenance) and indirect (on society in general, such as congestion).Structural EngineeringCivil Engineering and Geoscience

    Magnetic field compatible circuit quantum electrodynamics with graphene Josephson junctions

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    Circuit quantum electrodynamics has proven to be a powerful tool to probe mesoscopic effects in hybrid systems and is used in several quantum computing (QC) proposals that require a transmon qubit able to operate in strong magnetic fields. To address this we integrate monolayer graphene Josephson junctions into microwave frequency superconducting circuits to create graphene based transmons. Using dispersive microwave spectroscopy we resolve graphene's characteristic band dispersion and observe coherent electronic interference effects confirming the ballistic nature of our graphene Josephson junctions. We show that the monoatomic thickness of graphene renders the device insensitive to an applied magnetic field, allowing us to perform energy level spectroscopy of the circuit in a parallel magnetic field of 1 T, an order of magnitude higher than previous studies. These results establish graphene based superconducting circuits as a promising platform for QC and the study of mesoscopic quantum effects that appear in strong magnetic fields.QRD/Kouwenhoven LabQuTechApplied SciencesQRD/Goswami La

    Magnetic-Field-Resilient Superconducting Coplanar-Waveguide Resonators for Hybrid Circuit Quantum Electrodynamics Experiments

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    Superconducting coplanar-waveguide resonators that can operate in strong magnetic fields are important tools for a variety of high-frequency superconducting devices. Magnetic fields degrade resonator performance by creating Abrikosov vortices that cause resistive losses and frequency fluctuations or suppress the superconductivity entirely. To mitigate these effects, we investigate lithographically defined artificial defects in resonators fabricated from Nb-Ti-N superconducting films. We show that by controlling the vortex dynamics, the quality factor of resonators in perpendicular magnetic fields can be greatly enhanced. Coupled with the restriction of the device geometry to enhance the superconductors critical field, we demonstrate stable resonances that retain quality factors ≃105 at the single-photon power level in perpendicular magnetic fields up to BùƠ„ ≃20mT and parallel magnetic fields up to Bù„ ≃6T. We demonstrate the effectiveness of this technique for hybrid systems by integrating an In-Sb nanowire into a field-resilient superconducting resonator and use it to perform fast charge readout of a gate-defined double quantum dot at B=1T.QRD/Kouwenhoven LabQuTechApplied SciencesBUS/GeneralQCD/DiCarlo LabQN/Kouwenhoven La

    Ballistic superconductivity in semiconductor nanowires

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    Semiconductor nanowires have opened new research avenues in quantum transport owing to their confined geometry and electrostatic tunability. They have offered an exceptional testbed for superconductivity, leading to the realization of hybrid systems combining the macroscopic quantum properties of superconductors with the possibility to control charges down to a single electron. These advances brought semiconductor nanowires to the forefront of efforts to realize topological superconductivity and Majorana modes. A prime challenge to benefit from the topological properties of Majoranas is to reduce the disorder in hybrid nanowire devices. Here we show ballistic superconductivity in InSb semiconductor nanowires. Our structural and chemical analyses demonstrate a high-quality interface between the nanowire and a NbTiN superconductor that enables ballistic transport. This is manifested by a quantized conductance for normal carriers, a strongly enhanced conductance for Andreev-reflecting carriers, and an induced hard gap with a significantly reduced density of states. These results pave the way for disorder-free Majorana devices.QRD/Kouwenhoven LabQN/Conesa-Boj LabQRD/Wimmer LabQubit Research DivisionQN/Bakkers LabBUS/GeneralQRD/Goswami La

    Measurement of the diffractive cross-section in deep inelastic scattering

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    Diffractive scattering of γ∗p→X+N\gamma^* p \to X + N, where NN is either a proton or a nucleonic system with MN < 4M_N~<~4~GeV has been measured in deep inelastic scattering (DIS) at HERA. The cross section was determined by a novel method as a function of the γ∗p\gamma^* p c.m. energy WW between 60 and 245~GeV and of the mass MXM_X of the system XX up to 15~GeV at average Q2Q^2 values of 14 and 31~GeV2^2. The diffractive cross section dσdiff/dMXd\sigma^{diff} /dM_X is, within errors, found to rise linearly with WW. Parameterizing the WW dependence by the form d\sigma^{diff}/dM_X \propto (W^2)^{(2\overline{\mbox{\alpha_{_{I\hspace{-0.2em}P}}}} -2)} the DIS data yield for the pomeron trajectory \overline{\mbox{\alpha_{_{I\hspace{-0.2em}P}}}} = 1.23 \pm 0.02(stat) \pm 0.04 (syst) averaged over tt in the measured kinematic range assuming the longitudinal photon contribution to be zero. This value for the pomeron trajectory is substantially larger than \overline{\mbox{\alpha_{_{I\hspace{-0.2em}P}}}} extracted from soft interactions. The value of \overline{\mbox{\alpha_{_{I\hspace{-0.2em}P}}}} measured in this analysis suggests that a substantial part of the diffractive DIS cross section originates from processes which can be described by perturbative QCD. From the measured diffractive cross sections the diffractive structure function of the proton F^{D(3)}_2(\beta,Q^2, \mbox{x_{_{I\hspace{-0.2em}P}}}) has been determined, where ÎČ\beta is the momentum fraction of the struck quark in the pomeron. The form F^{D(3)}_2 = constant \cdot (1/ \mbox{x_{_{I\hspace{-0.2em}P}}})^a gives a good fit to the data in all ÎČ\beta and Q2Q^2 intervals with $a = 1.46 \pm 0.04 (stat) \pmComment: 45 pages, including 16 figure
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