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The Province of Zuid-Holland encourages the development of innovations to make the provincial road network more energy efficient. This is one way the province can contribute to reducing energy consumption and CO2 emissions in accordance with the Dutch energy agreement. To this end, the Province of Zuid-Holland, Strukton Civiel and TNO have conducted joint research on road surfacing that reduces rolling resistance and hence reduces fuel consumption and CO2 emissions. This document sets out the objective of the research, as well as the methods used and the research results (both in the laboratory and the field). It also looks ahead at the impact the results could have and how the construction of such energy-saving road surfacing could best be put out to tender by road authorities

De provincie Zuid-Holland stimuleert energie-reducerende innovaties die kunnen worden ingezet bij het (her)inrichten van het provinciaal wegennet. De provincie draagt onder andere op deze manier bij aan de doelstellingen van het Nederlandse energieakkoord betreffende het reduceren van energie en CO2 uitstoot. Eén van de innovaties die de provincie Zuid-Holland het afgelopen jaar heeft gestimuleerd, is het verminderen van het brandstofverbruik van voertuigen, en dus de CO2 uitstoot, door het ontwikkelen en toepassen van speciale wegdekken met een lage rolweerstand. In dit kader hebben de provincie Zuid-Holland, Strukton Civiel en TNO gezamenlijk onderzoek verricht ten behoeve van de realisatie van een wegdek dat de rolweerstand van banden verlaagt en daarmee brandstofverbruik en de CO2 emissies beperkt. In deze notitie worden het doel, de aanpak en de onderzoeksresultaten (in het laboratorium en in de praktijk) uitgelegd en toegelicht. Tevens wordt er een vooruitblik gegeven welke impact de resultaten hebben en hoe zo’n energiebesparend wegdek in de toekomst slim (functioneel) uitgevraagd kan worden door wegbeheerders.

De veroudering van het asfalt bindmiddel is een van de belangrijkste eigenschappen die een invloed hebben op de levensduur van open deklagen. In deze paper wordt de ontwikkeling van de veroudering van bindmiddel in de weg en met kunstmatige veroudering in het laboratorium beschreven in termen van reologische eigenschappen (magnitude en fasehoek van de complex modulus). Hiervoor wordt een database met daarin de ontwikkeling over vele jaren door middel van de reologische eigenschappen van bindmiddelen in proefvakken in het veld vergeleken met kunstmatig verouderde bindmiddelen in het laboratorium. De resultaten zijn geanalyseerd en vergeleken door deze uit te zetten in black space grafieken. Met behulp van deze black space grafieken worden verschillende laboratorium verouderingstechnieken geëvalueerd op basis van het produceren van representatieve reologische eigenschappen van de bindmiddelen.

Six different bitumina of comparable PEN grade were investigated to gain a relation between the composition

In 2008 Europe introduced the CEN standards for Asphalt Concrete. The Netherlands adopted the approach of functional requirements, rather than empirical, recipe based requirement. The experiences since 2008 showed that, although this approach allows for a better, more fundamental understanding of Asphalt Concrete, the current understanding is far from complete. Especially the effect of higher percentages (60-70%) of reclaimed asphalt was surprising, since it appeared to improve all functional requirements without the typical interrelation where an increase in stiffness corresponds with a decrease in fatigue resistance. These experiences led to the initiation of a program using the Dutch road network as a living laboratory (NL-LAB). In combination with actual laboratory research on mixes used in pavement construction projects, this program aims first of all to assess the effects of mixing and compaction on functional properties. Secondly, it tries to establish the predictive quality of lab determined functional properties for field performance. This paper describes the NL-LAB program and the results for the first four projects that are analysed. Considering the variation in the results, it is clear that more results are needed to arrive at any definite conclusions. However, the available data do show that the stiffness can be determined quite well and the values found are consistent. For the resistance against fatigue the results are fairly reproducible, but the trends are not consistent over the different projects. The resistance to moisture damage appears to be predicted fairly well from the lab data, but the variation in the individual indirect tensile tests is such that that actual value of the indirect tensile strength ratio remains to be determined. Finally, the cyclic triaxial test results vary considerably over the first two projects, but they are very consistent over the second two projects. This could be related to the mixing and compaction used in the different projects.

In this work ageing protocols for asphalt and mastics were developed and investigated; i.e representation of the field ageing and their acceleration degree. Here it was aimed to age laboratory prepared specimen analogous to naturally aged materials in the field and compare their material properties. Such simulation of ageing is of importance in order to potentially specify and objectively assess the properties of (novel) binders and asphaltic materials for Porous Aaphalt (PA). Hence, two ageing protocols were developed and investigated; one ageing protocol for asphalt mixtures and one for asphalt mastics. The rheological (DSR) properties of binders from the laboratory aged materials have been evaluated in comparison to binders from field aged specimen.

Het nieuwe onderzoeksproject NederLands Langjarig Asfalt Bemonsteringsprogramma (NLLAB) heeft als doel de materiaaleigenschappen tussen een gerealiseerd werk in de praktijk te vergelijken met de eigenschappen zoals gevonden voor een laboratorium gemengd en verdichte mengsels via typeonderzoek beproevingen. Van hetzelfde mengsel zoals toegepast is een asfaltwerk zijn proefstukken die in het laboratorium gemengd en verdicht zijn, beproefd volgens Proef 62 (RAW standaard 2010). De resultaten van de proefstukken, beproefd op stijfheid, indirecte treksterkte en de watergevoeligheid, weerstand tegen vervorming en weerstand tegen vermoeiing, worden vergeleken met de proefstukken gemengd in een asfaltcentrale en verdicht in het laboratorium en met proefstukken verkregen uit werk in de praktijk. Uit de resultaten van de eerste twee werken lijkt naar voren te komen dat de eigenschappen gevonden voor de in de laboratorium vervaardigde proefstukken zeker niet direct representatief zijn voor de eigenschappen van in werken in de praktijk en dat de reproduceerbaarheid van de resultaten voor een enkele van de beproevingen in een tweede experiment te wensen overlaat.

Omdat Asset Management steeds belangrijker wordt, heeft TNO een Road Map opgesteld waarin staat welke meet-, model- wn simulatietechnieken (MMS) in de toekomst voor goed Asset Management ontwikkeld moeten worden. Het doel is te komen tot hoogwaardige technologie voor de ondersteuning van beheer en onderhoudsbeslissingen van vitale delen van de weginfrastructuur

The work addressed involves the preparation and application of a compartmented polymer fibre, containing multiple separated domains with liquid agent for controlled release. The created fibre is a design for improvement to the existing liquid encapsulated self-healing systems such as fibre reinforced composites, i.e. increasing the released volume per intersection and maintaining self-repairing functionality. Additionally, we have focused on optimization of the fibre mechanical properties and control over liquid vacuole morphology.

Inspired by the current state-of-the-art and the progressing advancements in the field of self-healing materials, this thesis addresses several novel routes to advance the concept of liquid-based self-healing polymer systems. This thesis presents the concept and characterisation of a one-component solvent-based healing mechanism for thermoplastic materials and in addition to the healing strategy, a new capsular architecture is proposed for the purpose of simultaneous release of two reactants at the same location. Other liquid container designs are investigated to enhance the liquid release upon fracture (also in the case of multiple healing events) and come with less scarification of the intrinsic material properties. Chapter 2 describes the theoretical and experimental evaluation of all the material system parameters that are significant in the performance of a one component solvent-induced selfhealing mechanism for thermoplastic materials. Parameters that are investigated include solvent sorption rates, solvent induced depression of Tg and polymer diffusion coefficients. In Chapter 3 autonomous solvent-induced self-healing mechanism for PMMA are presented and investigated. The self-healing of the mechanical properties is experimental validated for different solvents and capsule volume concentration as a function of the healing time. In Chapter 4 the capsule-composite thermoplastic self-healing material is characterised qualitatively and quantitatively by X-ray tomography using SEM-based and Synchrotron X-ray facilities. The techniques allow detailed investigation into the release volume and kinetics ofhealing-agent at the damaged site. Chapter 5 presents a novel microcapsular architecture, designed for the encapsulation of two individual liquids within a single microscopic structure. These binary microcapsules have a central liquid core and are peripherally decorated with the second liquid component, which is achieved by the synthesis and application of liquid-filled Pickering particles. Chapter 6 presents a numerical study into the influence of the microcapsule geometrical shape on the performance of a self-healing material. Classical spherical shapes are compared to cylindrical ones with varying degree of anisotropy and spatial orientation. In Chapter 7 production routes are evaluated to obtain anisotropic rod-like microcapsules. The investigated routes involve droplet deformation and encapsulation in shear and elongational flow, by usage of a modified ink-jet printing technique and by creation of stable anisotropic droplets in suspension using Pickering particles. In Chapter 8 the concept for a compartmented liquid-filled fibre is given, providing an alternative to the continuous capillaries and discrete spherical microcapsules currently applied in the field of self-healing. Control over the morphology allows production of fibres with different mechanical properties that are in the order of standard composite matrix materials and have slightly lower failure strains.

This chapter aims at combining new insights in the field of (liquid encapsulated) self healing polymer systems as well as nanoparticle reinforced polymers to set the direction for the development of nanoparticle reinforced self healing polymers. In the case of self healing polymers the strategy is to minimise the volume fraction encapsulated healing agent for a desired healing performance. In the case of nanoparticle reinforced polymers the challenge is to maximise the mechanical property improvement for a certain fraction of anoparticles. For both systems the property to be optimised, i.e. the healing potential or the strengthening effect, is mathematically shown to depend on the aspect ratio of the added ingredient as well as its volume fraction. The chapter ends with a first exploration of the use of nanoparticle reinforcement to get attractive repetitive self healing behaviour in a polymer system still meeting minimal mechanical properties. 1. Introduction 2. Microstructured self healing polymer systems 2.1 Liquid-based self healing thermosetting polymers 2.2 Liquid-based self healing thermoplastic polymers 2.3 Geometrical aspects in encapsulation 3. Nanoparticle reinforced self healing polymer systems 3.1 Modelling the modulus of nanoparticle reinforced polymers 3.2 Experimental validation for non-self healing systems 3.3 Design of a self healing nanoparticle reinforced composite 4. Concluding remarks References

In this work X-ray microtomography was used to observe fracture and healing processes in a liquid-based self-healing thermoplastic material. The method was able to produce data of sufficient resolution (

In this numerical study the release of healing agent for liquid-based self-healing systems for elongated microcapsules is studied and compared with that for the usual spherical capsules. It is shown that a high aspect ratio and a proper spatial orientation of the elongated capsules have a positive influence on the calculated release of liquid healing agent per crack area. Consequently, considerable reductions of capsule loading concentrations for a particular healing efficiency are suggested in order to preserve the material intrinsic properties to a larger extend. Furthermore, the model predicts the maximal degree of healing as function of the crack opening distance and the capsule dimensions and concentration.