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Roads are exposed to solar radiation for the entire duration of their service life; depending on the season, the intensity and level of exposure can vary for different locations leading to differences in the magnitude of the damage. In Australia, many local road authorities have already started understanding that their roads are deteriorating faster due to non-load related effects (i.e., environmental damage). The present paper discusses the damage caused by UV radiation on bituminous binders and explores the protecting effect provided by the use of end-of-life tires in the form of crumb rubber. The results suggest that adding crumb rubber to bituminous binders has the potential to significantly reduce the non-load related environmental damage caused by the UV radiation of the Sun.

RILEM Technical Committee 279 WMR is dedicated to the Valorization of Waste and Secondary Materials for Roads. Its Task Group 2 investigated Crumb Rubber (CR) as an additive to enhance the performance of bitumen. CR recycled from end-of-life tires (ELTs) was chosen for this investigation because crumb rubber modified bitumen (CRMB) has been used to improve bituminous mixtures performance for fatigue and reflective cracking. The success of these mixtures is due to the CRMB viscosity that allows the use of an increased amount of bitumen compared to conventional mixtures. Because the viscosity of the CRMB is a function of the CR surface, and presently various types of CRs are produced, it is crucial to verify how these materials perform as a bitumen modifier. Interlaboratory experiments were performed on four types of CR, obtained from mechanical grinding, cryogenic process, waterjet pulverization and reacted and activated rubber. Three base, 35/50, 50/70 and 70/100, bitumen were used for the modification. Mechanical and chemical properties of CRMB were investigated. Despite some differences in the non-mechanical tests, i.e., penetration, softening point and viscosity, the results of the mechanical tests (complex shear modulus) suggest that the bitumen penetration grade ultimately dictates CRMB response.

Supplemental material, sj-docx-1-wmr-10.1177_0734242X231154140 for Stakeholder perceptions on implementing design for disassembly and standardisation for heterogeneous construction components by Kostas Anastasiades, Joos Dockx, Marc van den Berg, Mario Rinke, Johan Blom and Amaryllis Audenaert in Waste Management & Research

Crystals 12(6), 755 (2022). doi:10.3390/cryst12060755, It is well documented that most bituminous binders contain crystallisable material. This crystallisable fraction, often referred to as paraffinic or natural wax, is associated with the bitumen’s origin and has an influence on its rheological performance. In the literature, Differential Scanning Calorimetry (DSC) is the primary technique used to determine the melting and crystallisation behaviour of this waxy fraction. However, in bitumen, thermal transitions in DSC are typically very broad and can be combined with recrystallisation effects upon reheating. This work explores the potential crystallisation and melting process of a waxy and a wax-free bitumen via three different approaches: DSC, Wide-Angle X-ray Diffraction (WAXD) and Confocal Laser Scanning Microscopy (CLSM). The findings reveal that the DSC transitions of the waxy bitumen are in good agreement with the corresponding occurrence of WAXD signals and to some extent with the formation and disappearance of the surface microstructures which were followed at two cooling and heating rates. WAXD results additionally demonstrate that the crystalline material in bitumen is organised in an orthorhombic unit cell, typical for straight chain aliphatic structures. On the other hand, DSC and WAXD support the lack of crystallinity for the wax-free bitumen which could explain its featureless CLSM surface. Overall, the originality of this work resides in the disclosure of connections between crystallographic properties, thermal transitions and the surface micromorphology of bitumen., Published by MDPI, Basel

Light and heat are relevant factors for road pavements since they promote the aging of the asphalt surfaces [1], and a large amount of heating can intensify the Urban Heat Island (UHI) effect [2]. Contrariwise, the lack of light strongly affects visibility conditions, reducing safety [3]. The conventional black color of asphalt pavements absorbs light and stores a large amount of thermal energy, which can be reduced opting by the application of light-colored pavements using, for example, a transparent binder [3]. Industrial activities and road traffic are the main sources of pollutant emissions, mostly SO2 and NOx, which are hazardous atmospheric pollutants. There are several consequences at different scales caused by these harmful gases, such as intensification of the greenhouse effect, acid rain, and public health problems. With the use of nano-TiO2 into/over asphalt mixtures, and consequently with the functionalization process considering the photocatalytic and self-cleaning properties, road pavements become the ideal places to mitigate environmental pollution due to proximity to the emissions [4]. If a transparent binder modified with nanoparticles of TiO2 is used, pavements will present multifunction effects and benefits when submitted to high solar irradiation. The production at laboratory-scale of such pavements is presented in Figure 1. First, the transparent binder was modified with nano-TiO2 (0, 0.5%, 3.0%, 6.0% and 10.0%). Binder's workability was confirmed. It presented similar behavior as a polymer modified binder. In these binder samples, the addition of high contents of nano-TiO2 increased the rutting resistance, but it seemed to reduce fatigue life, except for the 0.5%. Also, the nano-TiO2 modification had a slight effect on the chemical functional indices. The best percentage of TiO2 was 10.0% considering rutting resistance and 0.5% concerning fatigue life.

Transparent binder is used to substitute conventional black asphalt binder and to provide light-colored pavements, whereas nano-TiO2 has the potential to promote photocatalytic and self-cleaning properties. Together, these materials provide multifunction effects and benefits when the pavement is submitted to high solar irradiation. This paper analyzes the physicochemical and rheological properties of a transparent binder modified with 0.5%, 3.0%, 6.0%, and 10.0% nano-TiO2 and compares it to the transparent base binder and conventional and polymer modified binders (PMB) without nano-TiO2. Their penetration, softening point, dynamic viscosity, master curve, black diagram, Linear Amplitude Sweep (LAS), Multiple Stress Creep Recovery (MSCR), and Fourier Transform Infrared Spectroscopy (FTIR) were obtained. The transparent binders (base and modified) seem to be workable considering their viscosity, and exhibited values between the conventional binder and PMB with respect to rutting resistance, penetration, and softening point. They showed similar behavior to the PMB, demonstrating signs of polymer modification. The addition of TiO2 seemed to reduce fatigue life, except for the 0.5% content. Nevertheless, its addition in high contents increased the rutting resistance. The TiO2 modification seems to have little effect on the chemical functional indices. The best percentage of TiO2 was 0.5%, with respect to fatigue, and 10.0% with respect to permanent deformation.

Research on recovery of phosphorus has gained consid erable attention and advancement in academia, and pilot projects have been carried out various private public partnerships during the lastdecade. For this reason nutrients other than phosphorus are the main focus of this study. The geographical scope of this study is the Netherlands and Europe.

Testing is the dominant technique for quality assurance of software systems. It typically consumes considerable resources in development projects, and is often performed in an ad hoc manner. This thesis is concerned with model-based testing, which is an approach to make testing more systematic and more automated. The general idea in model-based testing is to start from a formal model, which captures the intended behavior of the software system to be tested. On the basis of this model, test cases can be generated in a systematic way. Since the model is formal, the generation of test suites can be automated and with adequate tool support one can automatically quantify to which degree they exercise the tested software. Despite the significant improvements on model-based testing in the last 20 years, acceptance by industry has so far been limited. A number of commercially available tools exist, but still most testing in industry relies on manually constructed test cases. This thesis address this problem by presenting a methodology and associated tool support, which is intended to be used for model-based testing of communication protocol implementations in industry. A major goal was to make the developed tool suitable for industrial usage, implying that we had to consider several problems that typically are not addressed by the literature on model-based testing. The thesis presents several technical contributions to the area of model-based testing, including - a new specification language based on the functional programming language Erlang, - a novel technique for specifying coverage criteria for test suite generation, and - a technique for automatically generating test suites. Based on these developments, we have implemented a complete tool chain that generates and executes complete test suites, given a model in our specification language. The thesis also presents a substantial industrial case study, where our technical contributions and the implemented tool chain are evaluated. Findings from the case study include that test suites generated using (model) coverage criteria have at least as good fault-detection capability as equally large random test suites, and that model-based testing could discover faults in previously well-tested software where previous testing had employed a relaxed validation of requirements.

Constructed wetlands are one type of Sustainable Urban Drainage System (SUDS) that have been used for decades in The Netherlands. They provide stormwater conveyance and improve stormwater quality. European regulations for water quality dictate lower and lower concentrations for an array of dissolved pollutants. The increase in the required removal efficiency for these systems imposed in the Netherlands requires a better understanding of the characteristics of stormwater and the functioning of constructed wetlands as SUDs. This paper presents a brief overview of 5 different constructed wetlands from the Netherlands that have been implemented at least more than 10 years ago. Their efficiency and functioning is reviewed and a new method of assessment is described.

This paper presents the results of acoustic emission (AE) monitoring during fracture of textile reinforced inorganic phosphate cement (IPC) beams. The setup is based on three point bending with variable bottom span in order to control the dominant fracture mechanism from matrix cracking to interlaminar shear. The damage developed by the different stress fields is adequately monitored by AE and specifically by waveform parameters like duration, frequency content and energy. The AE parameters enable classification of the waveform according to their origin and shed light to the dominant stress field. In order to check the effect of elastic wave propagation, fracture mode classification is attempted not only by the whole population of AE data, but also separately by sensors at different distances from the center of the specimen. It is shown that the boundaries between matrix cracking and debonding/pull-out events strongly depend on the acoustic signal propagation path in this heterogeneous, laminated, platestructure. Ways to compensate for the effect of wave attenuation and distortion are discussed. Information about the load at the onset of damage and the dominant mode can give valuable input to numerical models for predicting the mechanical and fracture behavior of the TRC structures.

The project concerns a structural restoration study of the roof trusses of cinema theatre 'Roma' (1928) in Antwerp, Belgium. This extract is derived from a student report which was prepared for the course 'Stability of structures 3: finite elements'. A 3-dimensional computational structural analysis is carried out which allows for the verification of the current structural state.

Engineering materials and certain material applications require detailed preconditioning and specific thermal test schedules to be followed to obtain a correct evaluation of thermal expansion. Since a general test method cannot cover all specific requirements, details of this nature should be contained in the relevant material specification. The standard testing method to measure the linear thermal expansion is based on contact methods (ASTM E228-95, Standard Test Method for Linear Thermal Expansion of Solid Materials with a Vitreous Silica Dilatometer). The Thermal Mechanical Analysis (TMA), measures the change of length of the specimen during heating by using a vitreous silica push-rod or tube dilatometer. A big disadvantage of this method is the restricted size of the specimens. When using the TMA method on fiber reinforced composites; the small specimens required (maximum 5 x 5 mm cross section) are not representative for the behavior of the composite, so the method is not applicable. In this paper the coefficient of linear thermal expansion will be determined by using a contact (TMA) and a non contact method based on digital image correlation (DIC). This full field optical non contact method measures the in-plane displacements of the object surface. The aim of this study is to use both testing methods on different material in order to calibrate and verify the usability of the method to determine the linear thermal expansion coefficient. Results are compared with the TMA measuring technique. The reference measurements on aluminum and on pure IPC show that both techniques yield similar results, proving the usefulness of the proposed DIC technique for measuring the in plane deformation of a specimen at elevated temperatures. Results on textile reinforced IPC show the applicability of the DIC method for measuring macroscopic thermal expansion properties of fiber composite materials.

Many materials and certain material applications require detailed preconditioning and specific thermal test schedules to be followed to obtain a correct evaluation of thermal expansion. Since a general test method cannot cover all specific requirements, details of this nature should be contained in the relevant material specification. The standard testing method to measure the linear thermal expansion is based on contact methods (ASTM E228-95, Standard Test Method for Linear Thermal Expansion of Solid Materials with a Vitreous Silica Dilatometer). The Thermal Mechanical Analysis (TMA), measures the change of length of the specimen during heating by using a vitreous silica push-rod or tube dilatometer. A big disadvantage of this method is the restricted size of the specimens. When using the TMA method on fibre reinforced composites; the small specimens required (maximum 5 x 5 mm cross section) are not representative for the behaviour of the composite, so the method is not applicable. In this paper the coefficient of linear thermal expansion will be determined by using a contact (TMA) and a non contact method based on digital image correlation (DIC). This full field optical non contact method measures the in-plane displacements of the object surface [1]. By using software the data of the DIC measurement can be converted to strain values which can be used to calculate the coefficient of thermal expansion. The aim of this study is to use both testing methods on different material in order to calibrate and verify the usability of the method to determine the linear thermal expansion coefficient

I. INTRODUCTION In a market dominated by thermoset composite, new processing techniques need to be developed, in order to meet the new demands of the industry (ref.:1&2).Driven by the need to produce faster, thermoplastic composites seems to be the future. Theoretically that is an interesting alternative, but processing a material that requires 200°C, in conventional metal or thermoharder moulds seems to be impossible. The thermal expansion will be too great when using conventional moulding materials (ref.:3). In this paper a new technique is proposed using textile reinforced cement composite to produce a mould which can be produced faster with less material and is useable at high temperatures. II. THERMOPLASTICS Thermoplastic resins, or those which can be melted and remelted in contrast with thermoset resins, such as epoxy, which are hardened via chemical reaction. Thermoplastics offer a number of important advantages over thermosets like better toughness and damage tolerance, rapid fabrication cycle and the possibility of assembling substructures by welding. In order to produce large thermoplastic composite parts, for example ships or windmill blades, new mould construction techniques need to be developed. The aim of this work is to propose a new technique using textile reinforced cement composite to produce a mould for thermoplastic composites. III. TEXTILE REINFORCED CEMENT (TRC) Textile reinforced cement will be an ideal solution to develop a mould which can be used to produce large thermoplastic components. The TRC used in this study is a combination of inorganic phosphate cement (IPC) with random distributed chopped glass fibre textile reinforcement. IPC has been developed at the Vrije Universiteit Brussel and shows a neutral pH after hardening. Therefore, the glass fibres are hardly attacked by the concrete matrix. By using a fibre volume fraction which exceeds the critical fibre volume fraction, the fibres can ensure strength and stiffness at applied loads far exceeding the range in which matrix multiple cracking occurs. (ref.:4) Textile reinforced cementitious composites with glass fibres as reinforcement exhibit relatively high strength and ductility and thus provides an interesting new material for thin shells. Another big advantage is that it can resist high temperature, without producing toxic gasses and is also the absolute incombustibility, according to the European standard EN13501-1. All this advantages will make TRC an ideal material to develop a mould which can be used to produce thermoplastic composites. IV. MOULD PROTOTYPE Solid moulds were successfully produced using a first generation of inorganic phosphate cement (ref.:5). In this study thin shell type moulds will be produced to test the possibilities of this new moulding technique. Several cases are worked out One of the preliminary cases is the development of mould replacing the original thermo harder mould. Initial test (shrinkage measurements, the influence of temperature on the mass loss, production of moulds with different matrix compositions) were performed in order to optimise the behaviour of the matrix and the composite. The aim is to use these tests to optimize the material properties, shrinkage behaviour and surface quality. The future work of this development is to produce a mould capable to produce large thermoplastic composites. In the scope of this paper an experiential project will be setup in order to determine the possibilities using thermoplastics in a TRC mould. REFERENCES [1] Global Composites Market 2005-2010: Opportunities, Markets and Technologies Lucintel January 1, 2005- Pub ID: EC1469876 [2] Ginger Gardiner, Wind Blade Manufacturing, Part II: Are thermoplastic composites the future? High Performance Composites, 10/21/2008 [3] Lars Weigel, The stuff dreams are made of, New Energy magazine, March 2007 [4] J. Blom , H. Cuypers P,. Van Itterbeeck, J. Wastiels, Modelling the behaviour of Textile Reinforced Cementitious composites under bending, Prague, Fibre Concrete 4th International Conference, p.205- 210, 2007 [5] S. Faignet, P. Bauweraerts, J. Wastiels and X. Wu ,Materials Processing Technology Mineral Polymer tooling system for making Textile Reinforced Inorganic Phosphate Cement composite moulds J. Blom1, P. Van Itterbeeck1, J. Van Ackeren1, J. Wastiels1 1Department of Mechanical Engineering, Vrije Universiteit Brussel Pleinlaan 2, 1050 Brussels Belgium email: johan.blom@vub.ac.be, petra.van.itterbeeck@vub.ac.be, johan.van.ackeren@vub.ac.be,jan.wastiels@vub.ac.be prototype fibre reinforced composite parts V.U.B, Belgium,Journal of Materials Processing Technology 48 (1995) 757-764 This document was created with Win2PDF available at http://www.win2pdf.com. The unregistered version of Win2PDF is for evaluation or non-commercial use only. This page will not be added after purchasing Win2PDF.

Triage är ett relativt nytt begrepp inom svensk akutsjukvård och det är först under senare år som användandet brett ut sig över landets akutmottagningar. Internationellt sett har utvecklingen gått snabbare och bland annat Kanada och Australien har ett väl etablerat triagesystem. Triage används för att prioritera sökande patienters turordning och ett effektivt triagesystem visar på många fördelar. Enligt Hälso- och sjukvårdslagen ska förtur ges till de patienter som är i störst behov av vård. Att fatta beslut om en patients triagenivå kan vara en svår uppgift för sjuksköterskan. Syftet med litteraturstudien var att undersöka vilka faktorer som påverkar sjuksköterskan i beslutsfattandet om patientens triagenivå på akutmottagning. Studien utfördes som en litteraturöversikt och 13 vetenskapliga artiklar granskades och bearbetades. Resultatet visar att triageprocessen är komplex och dynamisk. Beslutsfattandet påverkas av sjuksköterskans färdighet, sjuksköterskans personliga egenskaper samt sjuksköterskans yttre förutsättningar. Erfarenhet och kommunikativ förmåga är grundläggande faktorer vid beslutsfattandet av triagenivå. Svårigheten att fatta enhetliga triagebeslut beror delvis på att bedömningen sker av olika sjuksköterskor med varierande förmågor och egenskaper. Svårigheten att fatta korrekta och enhetliga triagebeslut visar på ett behov av mer forskning och utbildning inom ämnet.

Validerat; 20101217 (root)

Validerat; 20101217 (root)

Validerat; 20101217 (root)

The pavement infrastructure comprises 16.3 million kilometres worldwide, and the pavement-related industrial sectors are said to be responsible for 21% of the global Greenhouse Gas (GHG) emissions worldwide (Plati, 2019). Sustainable actions on materials for those pavement layers mostly consider replacing (i) natural aggregates (NA) with recycled ones and (ii) Portland cement (PC) used as binder/stabiliser with binders with a lower ecological footprint. This research investigates the possibility of incorporating recycled asphalt pavement (RAP) as an aggregate replacement and alkali-activated material (AAM) as Portland cement (PC) replacement in/for base layer materials. So far, most studies focused on the use of RAP and PC or supplementary cementitious materials. The combination of RAP with alkali-activated matrices may be an even more sustainable solution, given that not only the aggregate is recycled, but also PC is absent from the matrix. Properly designed AAMs are stronger and more durable than PC-based materials. It is, therefore, very likely that the employment of RAP in AAM will result in materials that achieve the minimum requirements for road applications. This research produced an alkali-activated material containing fine and/or coarse RAP aggregates (RAP-AAM) as a replacement for natural aggregates to be used as base layers of pavements. The main objective of this thesis is to determine whether AAM can incorporate high amounts of RAP and be used as pavement base layers without compromising mechanical and durability performance. During this research, two innovative characterization methods were used as an alternative to those often employed for Portland concrete. Firstly, the observation of the interfacial transition zone (ITZ) was improved by combining a laser scanning confocal microscope (LSCM) and a scanning electron microscope (SEM). The combination of both techniques permitted a better observation of the heterogeneous asphalt coating of the RAP particles, the presence of clusters, and cracks at the border and within the activated matrix. Secondly, the thesis proposes an alternative methodology to observe and quantify the shrinkage of RAP-AAM or any other cementitious materials by employing simplified optical imaging. Although this method only allows for the observation of total shrinkage, it is an almost inexpensive method that could give a clear indication of volume changes over time. The experimental data demonstrated that an ideal alkali-activated binder composition to produce RAP-AAM lean concrete would have 10% MK replacement (BFS vol%) and the activator would have 8% Na2O and Ms= 0 (i.e., activated with NaOH and no sodium silicate). This selection was based on the minimum activator amount required to reach the target compressive strength for a weak to medium lean concrete (5 to 10 MPa), while also minimizing the shrinkage effect. The durability assessment to freeze and thaw indicated similar performance for RAP-AAM and reference (RAP-PC). The findings of this research showed that RAP-AAM is a promising material for pavement base layers and more investigation is needed on long-term strength and durability.

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