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  • 1.
    Al-Ayish, Nadia
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Samhällsbyggnad.
    Mueller, Urs
    RISE - Research Institutes of Sweden (2017-2019), Samhällsbyggnad.
    Karaxi, E. K.
    National Technical University of Athens, Greece.
    Kartsonakis, I. A.
    National Technical University of Athens, Greece.
    Charitidis, C. A.
    National Technical University of Athens, Greece.
    De Meyst, L.
    Ghent University, Belgium.
    Safety and sustainability of new admixtures for durable concrete2019Ingår i: Durable Concrete for Infrastructure Under Severe Conditions: Smart Admixtures, Self-responsiveness and Nano-additions, 2019Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    The sustainability of concrete infrastructures is highly dependent on the durability. A longer service life with low repair work reduces the resource use and hence the greenhouse gas emissions. New admixtures based on nanomaterials have the possibility to increase the service life. However, it is also important to consider the embodied impact of the material and safety issues concerning new nanomaterials. Here we present an overview on the latest developments on the safety and sustainability of some novel admixtures.

  • 2.
    Appelquist, Karin
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB.
    Mueller, Urs
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB.
    Utveckling av ett nytt funktionstest för ASR i betong2014Ingår i: CBI-nytt, ISSN 0349-2060, nr 2, s. 10-11Artikel i tidskrift (Övrigt vetenskapligt)
  • 3.
    Appelquist, Karin
    et al.
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Mueller, Urs
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Trägårdh, Jan
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Detection of potential alkali-silica reactivity of aggregates from Sweden2017Konferensbidrag (Övrigt vetenskapligt)
  • 4.
    Boubitsas, Dimitiros
    et al.
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Tang, Luping
    Chalmers University of Technology, Sweden.
    Fridh, Katja
    Lund University, Sweden.
    Mueller, Urs
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Utgenannt, Peter
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Frost Resistance of Concrete – Experience from Long-Term Field Exposure2018Rapport (Övrigt vetenskapligt)
    Abstract [en]

    This report presents the results from a research project financed by Trafikverket, the Swedish Transport Administration, co-financed by Cementa AB.

    The purpose of this project is to investigate concrete specimens exposed to a de-icing salt highway environment at Highway 40 close to Borås after about 20 years. The project work was divided into two parts: Part One for frost resistance of concrete and Part Two for chloride ingress and reinforcement corrosion.

    In Part One, more than 100 types of concrete mixes with different binder types/combinations, water-binder ratios (w/b) and air contents exposed at three field test sites were examined for external and internal frost damage by measurements of the changes in volume of, and in ultrasonic transmission time through, the specimens. Furthermore, some laboratory tests were carried out to supply necessary data for modelling and identify the possible mechanisms causing frost damage.

    The results show clearly that the highway environment is the most aggressive with regard to external frost damage. Further, the results from this study show that the existence of entrained air and the water-binder ratio are the main parameters influencing the resistance of concrete to external salt-frost damage. Furthermore, the concrete mixes with CEM I, CEM I + 5 % silica, CEM II/A-LL, CEM II/A-S and CEM I + 30 % slag as binder with entrained air and a water/binder ratio of 0.4 or below, has good resistance to internal and external frost damage. Results show that concrete containing large amounts of slag as part of the binder (CEM III/B) have the severest scaling, irrespective of its content of entrained air.

    Comparing results from laboratory testing of salt-frost resistance in accordance with SS 13 72 44 (the ‘Slab test’ in CEN/TS 12390-9) with results after nineteen years’ exposure at the highway exposure site shows that the laboratory standard classifies most concrete qualities correctly.

    However, there is an indication that the laboratory test method may overestimate the scaling resistance of concrete containing a medium to high content of slag as part of the binder. This indicates a need to consider a revision of the slab test procedure so that aging processes is better taken into consideration. A somewhat longer preconditioning time with at least partially an increased carbon dioxide content would for example lead to that the effect of carbonation is better reflected.

  • 5.
    Chozas, Valle
    et al.
    ACCIONA, Spain.
    Larraza, Iñigo
    ACCIONA, Spain.
    Vera-Agullo, Jose
    ACCIONA, Spain.
    Williams Portal, Natalie
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB, Betong & Berg.
    Mueller, Urs
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB, Betong & Berg.
    Da Silva, Nelson
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB, Betong & Berg.
    Flansbjer, Mathias
    RISE., SP – Sveriges Tekniska Forskningsinstitut.
    Synthesis and characterization of reactive powder concrete for its application on thermal insulation panels2015Ingår i: IOP Conference Series: Materials Science and Engineering, Institute of Physics Publishing (IOPP), 2015, Vol. 96, nr 1, artikel-id 012044Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper describes the synthesis and characterization of a set of textile reinforced reactive powder concrete (RPC) mixes that have been prepared in the framework of the SESBE project which aims to develop facade panels for the building envelope. In order to reduce the environmental impact, high concentration of type I and II mineral additions were added to the mixtures (up to 40% of cement replacement). The mechanical properties of the materials were analysed showing high values of compression strength thus indicating no disadvantages in the compression mechanical performance (∼140 MPa) and modulus of elasticity. In order to enable the use of these materials in building applications, textile reinforcement was introduced by incorporating layers of carbon fibre grids into the RPC matrix. The flexural performance of these samples was analysed showing high strength values and suitability for their further utilization.

  • 6. Falchi, L
    et al.
    Mueller, Urs
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB.
    Influence and effectiveness of water-repellent admixtures on pozzolana-lime mortars for restoration application2013Ingår i: Construction and Building Materials, ISSN 0950-0618, E-ISSN 1879-0526, Vol. 49, s. 272-280Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Pozzolana-lime mortars modified with water-repellent admixtures were designed and studied to obtain mortars for restoration application. Powdered silane and calcium stearates were mixed with pozzolana, lime and sand and the chemical-physical properties of the resulting mortars were evaluated by X-ray diffraction, electron microscopy (SEM-EDX), thermogravimetric analysis and FT-IR spectroscopy. The mechanical behavior, the pore structure and the hygric behavior were measured. The resistance of water-repellent mortars to the salt crystallization was evaluated. Both calcium stearates and powdered silane allowed good water-repellent protection even if the water-repellent agents and their dosage modified some physical properties and the hydration kinetic.

  • 7. Falchi, Laura
    et al.
    Mueller, Urs
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Fontana, Patrick
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Balliana, Eleonora
    Izzo, Francesca
    Zendri, Elisabetta
    Artificial weathering of water-repellent mortars suitable for restoration applications2014Ingår i: Hydrophobe VII / [ed] Mimoso, J.-M., Charola, A.E., 2014Konferensbidrag (Refereegranskat)
  • 8.
    Falchi, Laura
    et al.
    Ca’ Foscari University of Venice, Italy.
    Zendri, Elisabetta
    Ca’ Foscari University of Venice, Italy.
    Mueller, Urs
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB, Betong & Berg.
    Fontana, Patrick
    BAM Federal Institute for Materials Research and Testing, Germany.
    The influence of water-repellent admixtures on the behaviour and the effectiveness of Portland limestone cement mortars2015Ingår i: Cement & Concrete Composites, ISSN 0958-9465, E-ISSN 1873-393X, Vol. 59, s. 107-118Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Abstract Water-repellent mortars were prepared using different hydrophobic compounds as admixtures. Calcium and zinc stearates, silane/siloxane products (as liquid solution and powder) were mixed into limestone cement mortars for obtaining in-bulk water-repellent mortars suitable for building protection and resistant to the degrading action of water. The influences of the admixtures on the hydration and structure of the designed mortars were investigated by SEM, TG–DSC, FT-IR, XRD, and isothermal calorimetry. The effectiveness of these agents against water action was evaluated by using techniques and methods such as mercury intrusion porosimetry, water absorption tests and contact angle measurements. Siloxane products conveyed good water-repellent effectiveness, without strongly influencing the setting and hydration of the binder, while the zinc stearates slowed down the hydration reactions.

  • 9.
    Flansbjer, Mathias
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut.
    Honfi, Daniel
    RISE., SP – Sveriges Tekniska Forskningsinstitut.
    Vennetti, Daniel
    RISE., SP – Sveriges Tekniska Forskningsinstitut.
    Williams Portal, Natalie
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB.
    Mueller, Urs
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB.
    Wlasak, Lech
    Mostostal Warszawa SA, Poland.
    Strutural performance of GFRP connectors in Composite sandwich facade elements2016Ingår i: Journal of Facade Design and Engineering, ISSN 2213-302X, Vol. 4, nr 1-2, s. 35-52Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A systematic testing and modelling program has been developed for the verification of the structural performance of facade sandwich elements to take structural aspects into consideration in the SESBE research project, focusing on the development of “smart” facade elements.

    The present paper mainly focuses on the verification of the mechanical performance of the glass fibre reinforced polymer (GFRP) connectors of the novel type of facade element composed of reactive powder concrete (RPC) panels with foam concrete insulation between them. Because of the reduced thickness of the large facade elements, the performance of the connectors is critical for the entire structural concept. The first series of the testing and modelling programme concerning connector performance are presented here. The results suggest that sufficient strength and ductility of the connectors can be ensured using GFRP in the proposed thin light-weight facade elements.

  • 10.
    Flansbjer, Mathias
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut.
    Honfi, Daniel
    RISE., SP – Sveriges Tekniska Forskningsinstitut.
    Vennetti, Daniel
    RISE., SP – Sveriges Tekniska Forskningsinstitut.
    Williams Portal, Natalie
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB, Betong & Berg.
    Mueller, Urs
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB, Betong & Berg.
    Własak, Lech
    Mostostal Warszawa SA, Poland.
    Structural Concept of Novel RPC Sandwich Façade Elements with GFRP Connectors2016Ingår i: IABSE Congress Stockholm 2016: Challenges in Design and Construction of an Innovative and Sustainable Built Environment. Report, IABSE c/o ETH Hönggerberg , 2016, s. 2164-2171Konferensbidrag (Refereegranskat)
    Abstract [en]

    The SESBE research project aims to develop novel smart sandwich façade elements with high insulating capabilities while providing a reduced thickness in conjunction with superior mechanical and durability properties. The present paper mainly focuses on the verification of the mechanical performance of the glass fibre reinforced polymer (GFRP) connectors in the façade element composed of reactive powder concrete (RPC) panels with foam concrete insulation between them. Because of the reduced thickness of the large façade elements, the performance of the connectors is critical for the entire structural concept. A description of structural performance and results based on experimental methods and finite element (FE) analysis are presented.

  • 11.
    Flansbjer, Mathias
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, SP – Sveriges Tekniska Forskningsinstitut / Hållfasthet (BMh).
    Honfi, Daniel
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Bygg och Mekanik, Strukturer och Komponenter.
    Williams Portal, Natalie
    Mueller, Urs
    Larraza, Inigo
    Edgar, Jan-Olof
    Wlasak, Lech
    Structural behaviour of RPC sandwich façade elements with GFRP connectors2015Ingår i: VII International Congress on Architectural Envelopes. San Sebastian-Donostia, Spain. 2015-05-27--29, 2015Konferensbidrag (Övrigt vetenskapligt)
  • 12.
    Flansbjer, Mathias
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, SP – Sveriges Tekniska Forskningsinstitut / Hållfasthet (BMh).
    Malaga, Katarina
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB.
    Williams Portal, Natalie
    Dias Ferreira Da Silva, Nelson
    Mueller, Urs
    Larraza, Inigo
    Chozas, Valle
    Vera, Jose
    Reactive powder concrete for facade elements – A sustainable approach2015Ingår i: VII International Congress on Architectural Envelopes. San Sebastian-Donostia, Spain. 2015-05-27--29, 2015Konferensbidrag (Övrigt vetenskapligt)
  • 13.
    Flansbjer, Mathias
    et al.
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Williams Portal, Natalie
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Vennetti, Daniel
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Mueller, Urs
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Composite Behaviour of Textile Reinforced Reactive Powder Concrete Sandwich Façade Elements2018Ingår i: International Journal of Concrete Structures and Materials, ISSN 1976-0485, E-ISSN 2234-1315, Vol. 12, nr 1, artikel-id 71Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Within the EC funded project smart elements for sustainable building envelopes, carbon textile reinforcement was incorporated into reactive powder concrete, namely textile reinforced reactive powder concrete (TRRPC), to additionally improve the post-cracking behaviour of the cementitious matrix. This high-performance composite material was included as outer and inner façade panels in prefabricated and non-load bearing sandwich elements along with low density foamed concrete (FC) and glass fibre reinforced polymer continuous connecting devices. Experiments and finite element analysis (FEA) were applied to characterize the structural performance of the developed sandwich elements. The mechanical behaviour of the individual materials, components and large-scale elements were quantified. Four-point bending tests were performed on large-scale TRRPC-FC sandwich element beams to quantify the flexural capacity, level of composite action, resulting deformation, crack propagation and failure mechanisms. Optical measurements based on digital image correlation were taken simultaneously to enable a detailed analysis of the underlying composite action. The structural behaviour of the developed elements was found to be highly dependent on the stiffness and strength of the connectors to ensure composite action between the two TRRPC panels. As for the FEA, the applied modelling approach was found to accurately describe the stiffness of the sandwich elements at lower load levels, while describing the stiffness in a conservative manner after the occurrence of connector failure mechanisms. © 2018, The Author(s).

  • 14.
    Grigoriadis, K.
    et al.
    Queens University, UK.
    Whittaker, M.
    Queens University, UK.
    Soutsos, M.
    Queens University, UK.
    Sha, W.
    Queens University, UK.
    Napolano, L.
    STRESS S.C.AR.L, Italy.
    Klinge, A.
    ZRS Architekten Ingenieure GmbH, Germany.
    Paganoni, S.
    ZRS Architekten Ingenieure GmbH, Germany.
    Casado, M.
    ACCIONA Construction Technology Centre, Spain.
    Brander, Linus
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Rabade, Prieto
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Mueller, Urs
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Mousavi, Marjan
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    During, Otto
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Scullin, M.
    CDE Global Ltd, Uk.
    Correia, R.
    CREAGH Concrete, uk.
    Zerbi, T.
    STAM S.R.L, iTALY.
    Merli, I.
    VORTEX HYDRA S.R.L, iTALY.
    Ingrosso, I.
    CETMA, Italy.
    Attanasio, A.
    CETMA, Italy.
    Largo, A.
    CETMA, Italy.
    Improving the recycling rate of the construction industry2019Ingår i: Sustainable Construction Materials and Technologies, International Committee of the SCMT conferences , 2019Konferensbidrag (Refereegranskat)
    Abstract [en]

    Construction and Demolition Waste (CDW) accounts for approximately 25-30% of all waste generated across Europe each year. However, Waste Framework Directive 2008/98/EC requires from all EU member states to achieve at least 70% re-use, recycling or other recovery of non-hazardous CDW by 2020. In response, the Horizon 2020 RE4 Project (REuse and REcycling of CDW materials and structures in energy efficient pREfabricated elements for building REfurbishment and construction) consortium was set up. Its main aims are to assess the quality of various CDW fractions (e.g. mineral aggregate, timber, plastics, silt & clay), improve the quality of mineral aggregates and develop different building elements/components which contain at least 65% of CDW. Innovative building concepts will also be developed in an effort to improve recycling rates of future buildings through the use of prefabrication and modular design. The developed products and technologies will be assessed in a number of test sites by building 2-storey demonstration houses.

  • 15.
    Helsing, Elisabeth
    et al.
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Parg, Lisa
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Mueller, Urs
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Ellison, Tommy
    BESAB, Sweden.
    Hydrofoberande medel i sprutbetong: Inverkan på egenskaper och beteendet vid sprutning2017Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    Det övergripande målet med projektet är att få fördjupade kunskaper och erfarenheter när det gäller användning av hydrofoberande medel som tillsätts betongmassan i sprutbetong med lågalkaliska bindemedel, med syfte att förbättra sprutbetongens beständighet och brukbarhet. Resultaten från detta projekt bidrar till ökad förståelse för praktiska möjligheter med och begränsningar för hydrofoberande medel som tillsätts betongmassan i sprutbetong, och därmed minskar behovet av kostsamma fältförsök, med ” trial and error”.En stor del av projektet har ägnats åt att studera inverkan av hydrofoberingsmedlen på egenskaperna i det tidiga stadiet, då de är avgörande för den praktiska tillämpningen. Därutöver har inverkan på egenskaper som hållfasthetsutveckling och vidhäftningshållfasthet mätts. Vilken hydrofobicitet som dessa medel ger betongen har också undersökts. Dessa provningar har främst gjorts på pasta, bruk eller betong som gjutits på konventionellt sätt, alltså inte på sprutbetong. Därutöver har provsprutning gjorts med en betong med ett av medlen samt en referens utan hydrofoberingsmedel för att kartlägga beteendet vid sprutning. På prover av den sprutade betongen har vidhäftningshållfastheten, hydrofobiciteten och kloridinträngningen bestämts.Två hydrofoberande medel, Sitren P 750 (E) och Silres BS 1001 (W) har använts, båda baserade på organosilikater. Medel E grundar sig på modifierad siloxan som är anbringad på silikastoft och medel W är en vattenbaserad emulsion av silan/siloxan. De flesta provningarna har utförts dels med ett rent Portlandcement (Degerhamns Anläggningscement från Cementa) och dels ett Portland-flygaskecement (Slite Anläggning FA från Cementa). Båda är sulfatresistenta och lågalkaliska. Provningar med och utan accelerator har utförts.Använda utan accelerator påverkade medel W bindetid och värmeutveckling i betydligt högre grad än medel E. Medel W hade en klart retarderande effekt. Denna effekt kunde dock i hög grad kompenseras genom tillsats av en accelerator. 28-dygnshållfastheten sänktes med båda hydrofoberingsmedlen, mest med medel W, men även i detta fall kompenserades denna effekt till viss del av acceleratorn. Acceleratorn hade inte samma avgörande effekt när medel E användes.Vid provning på gjuten betong var vidhäftningen bättre och mindre spretig (mindre standardavvikelse) med medel W än med medel E. Hydrofobiciteten hos blandningar med de båda medlen vara jämförbar.Provprutningen genomfördes med medel W och accelerator. Med hydrofoberingsmedel erhölls samma konsitens med mindre mängd vatten. Beteendet vid sprutning med medel W var lika bra som eller något bättre än utan. Hydrofoberingsmedlet påverkade inte sprutbetongens vidhäftning. Vattenabsorptionen hos sprutbetongen med hydrofoberingsmedel var c:a 30 % lägre än utan sådant medel, och motståndet mot kloridinträngning ungefär 40 % bättre.

  • 16.
    Hesselgren, Lars
    et al.
    PLP Architecture, Sweden.
    Andreasson, Ingemar
    LogistikCentrum, Sweden.
    Mueller, Urs
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Prieto Rábade, Miguel
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Janhäll, Sara
    RISE - Research Institutes of Sweden, Samhällsbyggnad, Energi och cirkulär ekonomi.
    NuMo – New Urban Mobility: New urban infrastructure support for autonomous vehicles2019Rapport (Övrigt vetenskapligt)
    Abstract [en]

    Foreword All transport systems have a certain capacity determined by its configurations. For cars the most efficient current form is constant speed driving, e.g. the motorway. Its capacity is limited by the time separation between vehicles. Any transport system that stops because of congestion or other causes by definition sees its capacity reduced to zero. Hence traffic jams are hugely disruptive. Public transport operates on a model inherited from the 19 th Century. Vehicles (buses, trams, railways, metros) run on a regular (timetabled) basis and stops at every station (bus stop). Since there is no pre-booking and the need of transport is hard to foresee, the vehicles are often almost empty, at other times hugely congested. The NuMo technology emerges from decades of work across the whole transportation industry. Autonomous electric vehicles (AEVs) equipped with vehicle-to-vehicle (V2V) communication can safely keep shorter distances. In practical terms this means that a platooned car system has the same capacity in one lane as a double-lane motorway. Automated intelligent controls ensure that the NuMo systems never stops, thus achieving the highest capacity. Instead of waiting for the mass deployment of fully automated vehicles, NuMo starts with dedicated networks that integrate tightly with existing infrastructure for step-wise smooth transition to fully automated transport system. NuMo includes an on-demand public transport system which only runs when it is needed. The system will take advantage of close-spacing possible with robot controls – vehicles can run close together and also use less road width by less wiggling. Equally importantly stations and access to the normal road network is arranged such that the traffic flow never stops. The urban impact can be imagined by understanding the impact of modern public transport systems currently under construction. Some of them are underground to avoid disrupting the street patterns. Some are elevated, some rely on physical separation at grade. One interesting option is to use tunnels underground or in water to further reduce disruption. Many cities are abandoning the traditional port infrastructure giving huge opportunities to again regard water as a connector rather than something to cross. The NuMo system uses all of those techniques and detailed design studies are under way for each of those options. NuMo will make an important contribution to environmental sustainability in many respects. Firstly, it will accelerate adoption of electric propulsion; secondly it will encourage vehicle sharing; and thirdly by only running when needed will save on unnecessary movements and finally its construction costs will be less than conventional systems. Sketches of NuMo networks are presented on places as diverse as Stockholm, Gothenburg and New York. Naturally the system will also be crucial in the development of new cities. This report is a summary of the studies performed within the project “New urban infrastructure support for autonomous vehicles” financed by Vinnova through the Strategic Innovation Program InfraSweden2030. The aim is to explore the infrastructure support to accelerate the introduction of autonomous electric vehicles for future mobility.

  • 17. Kargol, M A
    et al.
    Mueller, Urs
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB.
    Properties and performance of silane: blended cement systems2013Ingår i: Materials and Structures, ISSN 1359-5997, E-ISSN 1871-6873, Vol. 46, nr 9, s. 1429-1439Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The paper presents the results of a study dealing with the performance of water repellents on hardened blended cement pastes. Since on the European market Portland cement does not play the dominant role anymore and due to the new national and European policies concerning Greenhouse Gases and sustainability, cement manufacturers produce more and more blended cements (CEM II-CEM V). Nevertheless, the majority of experience concerning the efficacy of water repellents is gained from Portland cement; therefore knowledge in regard to the interactions of blended cement with water repellent agent is minimal. Two silane-based products were applied on 'fresh' and carbonated cement substrates containing limestone, fly ash, slag and trass, and were investigated in terms of their functionality. The evaluation of the treatments' performance and effectiveness were assessed using various laboratory measurements. Hydrophobicity, water absorption, colour changes and the penetration depth of silanes into the substrate were evaluated before and after artificial aging experiments. Moreover, the outdoor weathering test was performed to shed light on treated surface appearance in a 'real' outdoor environment. The results showed that surface wettability was independent on water ingress or colour variations, especially for cement specimens artificially aged by accelerated carbonation. Cement pastes containing slag and trass seemed to more distinctly affect the water repellents' surface performance.

  • 18.
    Lundgren, Monica
    et al.
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Babaahmadi, Arezou
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Mueller, Urs
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Exposure experiments in sulfate containing solution, including exposure at low temperature2018Rapport (Övrigt vetenskapligt)
    Abstract [en]

    This report describes results of an investigation on the sulfate resistance of dual blended binder of mortar and concrete specimens over a period of 1 year. The focus is on showing the importance of the chemistry of the components when discussing sulfate resistance and the relation of that to the hydrate phase assemblage. Moreover the importance of the test method for evaluations is pointed out.

  • 19.
    Lundgren, Monica
    et al.
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Helsing, Elisabeth
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Babaahmadi, Arezou
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Mueller, Urs
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    State-of-the-Art Report on: Material Type, Requirements and Durability aspects of Sprayed Concrete in Tunnels2018Rapport (Övrigt vetenskapligt)
    Abstract [en]

    The report summarizes a state-of-the-art for sprayed concrete applied for ground support in tunnel environments, in Sweden and several European countries, with focus on the components, the mix design and the guidelines and specifications. It focuses also on the addition of supplementary cementitious materials (SCM), where the use, the common practice and the long-term experience vary from country to country. The report presents numerous examples of applications in Sweden and seven other European countries. It also gives an overview about the possible exposure risks and summarizes the relevant durability issues. Along with specifications in international standards and guidelines it also reviews the national requirements in Sweden, Norway, Finland, Austria, France, Germany and Switzerland.

  • 20.
    Malaga, Katarina
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB.
    Mueller, Urs
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB.
    Relevance of hydrophobic and oleophobic properties of antigraffiti systems on their cleaning efficiency on concrete and stone surfaces2013Ingår i: Journal of materials in civil engineering, ISSN 0899-1561, E-ISSN 1943-5533, Vol. 25, nr 6, s. 755-762Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The problem of graffiti is not entirely restricted to urban areas, but also appears frequently in rural communities and along traffic infrastructure. Besides its aesthetic and societal effects, graffiti cause considerable removal costs and subsequent costs for repairing damages caused by improper graffiti removal. Over the last two decades, strategies have been developed to combat graffiti in the built environment, including the development of protective measures in the form of antigraffiti systems (AGSs). Antigraffiti systems promise to be affordable and easily applicable for a wide range of substrates, and many products have already been on the market for many years. In practice, however, successful application of AGS and removal of graffiti depend on many factors in which the type of coating and condition of the substrate play critical roles. The optimal environmental goal is to use AGS without any cleaning chemicals except for pure water. Available studies on the behavior of the same AGS on various substrates can show completely different results concerning the cleaning efficacy and the durability of the AGS under different climatic conditions. The question of which properties of an AGS are most essential for its efficiency has still not been fully investigated. The goal of this study was to investigate cleaning efficacy in conjunction with hydrophobic and oleophobic properties of the AGS on different substrates. The results showed that hydrophobicity and oleophobicity are important for dense substrates but have a low influence on porous substrates. In this case, cleaning efficiency is majorly determined by the physical properties of the substrates.

  • 21. Meng, Birgit
    et al.
    Fontana, Patrick
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Mueller, Urs
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Bürgisser, Philip
    Influence of natural pozzolans on the risk of Alkali Silica Reaction2013Ingår i: International Conference on Advances in Cement and Concrete Technology in Africa, BAM Federal Institute for Materials and Testing , 2013, s. 801-808Konferensbidrag (Refereegranskat)
  • 22.
    Meng, Birgit
    et al.
    BAM Federal Institute for Materials Research and Testing, Germany.
    Mueller, Urs
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB.
    Performance of a new anti-graffiti agent used for immovable cultural heritage objects2014Ingår i: International Journal of Architectural Heritage, ISSN 1558-3058, E-ISSN 1558-3066, Vol. 8, nr 6, s. 820-834Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Cultural Heritage objects are in many cases invaluable and irrecoverable, therefore their protection is a major goal. One threat arises by intentionally defacing such objects with graffiti. One possibility to face the imminent threat is the application of a surface protection in form of anti-graffiti systems (AGS). However, the knowledge about the performance and durability of AGS on substrates used for historical buildings is still fragmented. The goal of the present study was to investigate the performance of a newly developed anti-graffiti agent in comparison to a selection of commercial anti-graffiti agents on different substrates that were used for historical buildings. Four commercial anti-graffiti agents with different chemical formulations were selected and tested with the new agent on different stone and brick substrates. The results showed clearly that AGS based on dense, water-vapor impermeable coatings are not suitable to porous substrates such as sandstone, brick, or porous limestone due to their impairment of the hygric properties and the visual appearance of a substrate. The new agent could not completely reach the cleaning efficacy of the dense coatings but exhibited a much lower impact on the properties of the substrate and was therefore better compatible to historical surfaces.

  • 23.
    Miccoli, L.
    et al.
    BAM Bundesanstalt für Materialforschung und -prüfung, Germany.
    Fontana, P.
    BAM Bundesanstalt für Materialforschung und -prüfung, Germany.
    Mueller, Urs
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB.
    In-plane shear behaviour of earthen materials panels strengthened with polyester fabric strips2016Ingår i: Structural Analysis of Historical Constructions: Anamnesis, diagnosis, therapy, controls - Proceedings of the 10th International Conference on Structural Analysis of Historical Constructions, SAHC 2016, CRC Press/Balkema , 2016, s. 1099-1105Konferensbidrag (Refereegranskat)
    Abstract [en]

    An experimental investigation was carried out to study the in-plane shear behaviour of earthen material panels strengthened with polyester fabric strips. Strengthened panels were developed to exploit the strength potential of earthen materials and to solve its lack of tensile strength, significantly improving not only strength but also ductility. Three earthen materials were considered: cob, earth block masonry (EBM) and rammed earth (RE). As first approach the strengthening configuration, based on different adhesive materials, was tested only for cob panels. As part of the study the results of a big testing campaign of unstrengthened panels were considered. Seven strengthened panels were tested in diagonal compression/shear.A unique reinforcement orientation was used. The results of these tests are presented in this paper, and include the load-displacement behaviours, crack patterns, failure modes. The results showed that the reinforcement was the most effective in EBM panels, with increase in strength and ductility observed. In RE and cob panels the reinforcement did not likely contribute significantly to the shear resistance, due to a lack of embedment length of the strips. Instead, in EBM it was likely that the vertical reinforcement acted in tension to restrain shear induced dilation and to restrain sliding.

  • 24.
    Miccoli, L.
    et al.
    BAM Federal Institute for Materials Research and Testing, Germany.
    Mueller, Urs
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB.
    Fontana, P.
    BAM Federal Institute for Materials Research and Testing, Germany.
    Mechanical behaviour of earthen materials.: A comparison between earth block masonry, rammed earth and cob2014Ingår i: Construction and Building Materials, ISSN 0950-0618, E-ISSN 1879-0526, Vol. 61, s. 327-339Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Earth represents one of the oldest construction materials, which is still utilised both in developed and in developing countries. In this paper a comparison of the mechanical performance of structural elements built in three basic techniques, earth block (adobe) masonry, rammed earth and cob, is presented. In order to gain better knowledge on the structural behaviour under static loads an extensive compression and diagonal compression (shear) test campaign was performed. First compression results showed brittle mechanical behaviour in the case of earth block masonry and rammed earth elements, whereas cob exhibited a very different stress-strain pattern: cob can deform beyond the elastic range with a gradual drop in capacity. Despite its low compressive strength, cob thus presents a relatively good performance within the earthen material range as far as shear behaviour is concerned. The data here reported represents a base for a further investigation on the dynamic behaviour of the three materials considered. The study was carried out within the framework of the project NIKER funded by the European Commission dealing with improving immovable Cultural Heritage assets against the risk of earthquakes.

  • 25.
    Miccoli, L.
    et al.
    BAM Federal Institute for Materials Research and Testing, Germany.
    Oliveira, D. V.
    University of Minho, Spain.
    Silva, R. A.
    University of Minho, Spain.
    Mueller, Urs
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB.
    Schueremans, L.
    Catholic University of Leuven, Netherlands.
    Static behaviour of rammed earth: experimental testing and finite element modelling2015Ingår i: Materials and Structures, ISSN 1359-5997, E-ISSN 1871-6873, Vol. 48, nr 10, s. 3443-3456Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The paper presents an experimental program aiming at assessing the mechanical performance of rammed earth walls, namely under compression and shear loading. Axial compression and diagonal compression tests were carried out for this purpose, which allowed determining important mechanical parameters, such as compressive strength, Young’s modulus, Poisson’s ratio, shear strength and shear modulus. Furthermore, it allowed assessing the level of non-linear behaviour of the respective stress–strain relationships as well as the failure modes. The experimental results were then used in the calibration of numerical models (finite element method) for simulating the non-linear behaviour of rammed earth under shear loading. Both macro- and micro modelling approaches were considered for this purpose. The total strain rotating crack model was used to simulate the behaviour of the rammed earth material, while the Mohr–Coulomb failure criterion was used to simulate the behaviour of interfaces between layers. In general, the numerical models achieved good agreement with the experimental results, but uncertainties related to the definition of the input parameters required to perform a sensitivity analysis. The compressive strength, the Poisson’s ratio, the tensile strength and the tensile fracture energy revealed to be the most important parameters in the analyses.

  • 26.
    Miccoli, Lorenzo
    et al.
    BAM Federal Institute for Materials Research and Testing, Germany.
    Drougkas, Anastasios
    National Technical University of Athens, Greece.
    Mueller, Urs
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB, Betong & Berg.
    In-plane behaviour of rammed earth under cyclic loading: Experimental testing and finite element modelling2016Ingår i: Engineering structures, ISSN 0141-0296, E-ISSN 1873-7323, Vol. 125, s. 144-152Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The purpose of this paper is to numerically simulate the in-plane behaviour of rammed earth walls under cyclic shear-compression tests. The experimental testing allowed obtaining the maximum horizontal loads, the displacement capacity and the level of non-linear behaviour of the respective load-displacement relationships as well as the failure modes. The calibration of the numerical model (finite element method) was carried out based on the experimental results. Within this framework, a micro-modelling approach was considered. The behaviour of the rammed earth material was simulated using a total strain rotating crack model. A Mohr-Coulomb failure criterion was used to reproduce the behaviour of the interfaces between the layers. Although the numerical results achieved a satisfactory agreement with the experimental results a sensitivity analysis of the parameters involved was performed. The sensitivity analysis aimed at determining which parameters of the model have a significant impact in the model's results. As expected the sensitivity analysis pointed out that the sliding failure occurrence is mainly influenced by two parameters of the interface elements: the interface tensile strength fit and the friction angle φ. Moreover the cohesion c and the layers thickness showed a limited effect on the shear behaviour. It should be noted that the results mentioned above are related to the cases where a significant level of vertical compressive stress σ is employed.

  • 27.
    Miccoli, Lorenzo
    et al.
    BAM Federal Institute for Materials Research and Testing, Germany.
    Fontana, Patrick
    BAM Federal Institute for Materials Research and Testing, Germany.
    Johansson, Gabriel
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB, Tillståndsbedömningar.
    Zandi, Kamyab
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB, Betong & Berg.
    Williams Portal, Natalie
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB, Betong & Berg.
    Mueller, Urs
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB, Betong & Berg.
    Numerical modelling of UHPC and TRC sandwich elements for building envelopes2015Ingår i: IABSE Conference 2015: Structural Engineering: Providing Solutions to Global Challenges, IABSE , 2015, s. 195-203Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper a modelling approach is presented to reproduce the mechanical behaviour of sandwich panels via finite element analysis. Two types of panels were investigated in this scope of work. The first sandwich element was a textile reinforced concrete (TRC) panel with cellular lightweight concrete insulation and the second configuration was an ultra-high performances concrete (UHPC) panel with aerated autoclaved concrete insulation. The goal was to obtain a reliable numerical strategy that represents a reasonable compromise in terms of sufficient accuracy of the element characteristics and the computational costs. The results show the possibility of describing the composite action in a full sandwich panel. The achieved modelling approach will later be used for the optimization of TRC and UHPC panels in terms of minimizing the thickness, identifying the number and location of connectors, as well as evaluating varying anchorage systems.

  • 28.
    Miccoli, Lorenzo
    et al.
    BAM Federal Institute for Materials Research and Testing, Germany.
    Fontana, Patrick
    BAM Federal Institute for Materials Research and Testing, Germany.
    Mueller, Urs
    RISE., SP – Sveriges Tekniska Forskningsinstitut.
    In-plane shear behaviour of earthen materials panels strengthened with polyester fabric strips2016Ingår i: Structural Analysis of Historical Constructions: Proceedings of the 10th International Conference on Structural Analysis of Historical Constructions (SAHC 2016), 2016, s. 1099-1105Konferensbidrag (Refereegranskat)
    Abstract [en]

    An experimental investigation was carried out to study the in-plane shear behaviour of earthen material panels strengthened with polyester fabric strips. Strengthened panels were developed to exploit the strength potential of earthen materials and to solve its lack of tensile strength, significantly improving not only strength but also ductility. Three earthen materials were considered: cob, earth block masonry (EBM) and rammed earth (RE). As first approach the strengthening configuration, based on different adhesive materials, was tested only for cob panels. As part of the study the results of a big testing campaign of unstrengthened panels were considered. Seven strengthened panels were tested in diagonal compression/shear.A unique reinforcement orientation was used. The results of these tests are presented in this paper, and include the load-displacement behaviours, crack patterns, failure modes. The results showed that the reinforcement was the most effective in EBM panels, with increase in strength and ductility observed. In RE and cob panels the reinforcement did not likely contribute significantly to the shear resistance, due to a lack of embedment length of the strips. Instead, in EBM it was likely that the vertical reinforcement acted in tension to restrain shear induced dilation and to restrain sliding.

  • 29. Miccoli, Lorenzo
    et al.
    Fontana, Patrick
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Ziegert, Christof
    Perrone, Chiara
    Mueller, Urs
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Charakterisierung und Modellierung der mechanischen Eigenschaften von Lehmsteinmauerwerk - Mechanical Characterization and Modelling of Earth Block Masonry2012Ingår i: Masonry, ISSN 1432-3427, E-ISSN 1437-1022, Vol. 16, nr 6, s. 279-292Artikel i tidskrift (Refereegranskat)
  • 30.
    Miccoli, Lorenzo
    et al.
    BAM Federal Institute for Materials Research and Testing, Germany.
    Garofano, Angelo
    Swiss Federal Institute of Technology in Lausanne, Switzerland.
    Fontana, Patrick
    BAM Federal Institute for Materials Research and Testing, Germany.
    Mueller, Urs
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB, Betong & Berg.
    Experimental testing and finite element modelling of earth block masonry2015Ingår i: Engineering structures, ISSN 0141-0296, E-ISSN 1873-7323, Vol. 104, s. 80-94Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The current paper focuses on the determination of reliable numerical models of earth block masonry wallettes under different loading conditions. Uniaxial compression and diagonal compression tests were performed. Experimental behaviour was modelled with a non-linear model able to describe the cracking behaviour. The simplified approach based on macro-modelling shows a satisfactory accuracy and low computational costs. The results reproducing the uniaxial compression are in good correspondence with the post-elastic behaviour observed in the experimental campaign. The micro-modelling approach adopted to reproduce the shear behaviour, even with high computational cost, represents a suitable tool to predict the masonry collapse mechanism.

  • 31. Miccoli, Lorenzo
    et al.
    Garofano, Angelo
    Fontana, Patrick
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Mueller, Urs
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Static behaviour of earth block masonry: experimental testing and Finite Element Modelling2014Ingår i: 9th International Masonry Conference (IMC), Guimarães, Portugal, 2014Konferensbidrag (Övrigt vetenskapligt)
  • 32.
    Miccoli, Lorenzo
    et al.
    BAM Bundesanstalt für Materialforschung und –prüfung, Germany.
    Mueller, Urs
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Pospíšil, Stanislav
    Institute of Theoretical and Applied Mechanics, Czech Republic.
    Rammed earth walls strengthened with polyester fabric strips: Experimental analysis under in-plane cyclic loading2017Ingår i: Construction and Building Materials, ISSN 0950-0618, E-ISSN 1879-0526, Vol. 149, s. 29-36Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study analyses the mechanical behaviour under pseudo-dynamic loading of structural elements built in rammed earth and strengthened with polyester fabric strips. This strengthening technique was developed to exploit the strength potential of rammed earth and to solve its lack of tensile strength. For this reason, in-plane cyclic tests were carried out to investigate the shear behaviour of unstrengthened and strengthened walls. The strengthening technique requires low-tech equipment and workmanship, uses readily available, not expensive and industrially standardised materials. The experimental results were analysed in terms of stiffness degradation, energy dissipation capacity and equivalent viscous damping. Although the unstrengthened and strengthened walls confirmed a limited ductile behaviour, the findings confirm that the strengthening contributes to limit the spread of the diagonal cracks and provide an increase of strength in terms of horizontal load and displacement capacity.

  • 33.
    Miccoli, Lorenzo
    et al.
    Bundesanstalt für Materialforschung und -prüfung, Germany.
    Silva, Rui
    University of Minho, Portugal.
    Oliveira, Daniel
    University of Minho, Portugal.
    Mueller, Urs
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Static behavior of cob: Experimental testing and finite-element modeling2019Ingår i: Journal of materials in civil engineering, ISSN 0899-1561, E-ISSN 1943-5533, Vol. 31, nr 4, artikel-id 04019021Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The aim of this paper is to implement a numerical model to reproduce the nonlinear behavior of cob walls under shear loading. Axial compression, pull-off, and diagonal compression tests were carried out to derive the mechanical parameters. In addition, the stressstrain relationships, the nonlinear behavior, and the failure modes were defined. The experimental results were then used to calibrate a finiteelement model. The material behavior was simulated through a macromodeling approach adopting the total strain rotating crack model. A sensitivity analysis was conducted to assess the effects of varying the parameters with higher uncertainty on the structural behavior. The numerical model achieved good correspondence with the experimental results in terms of simulation of the shear stress-shear strain relationship and of damage pattern.

  • 34.
    Mueller, Urs
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB.
    Internationella och nationella kommittéer om ASR i betong2014Ingår i: CBI-nytt, ISSN 0349-2060, nr 2, s. 11-Artikel i tidskrift (Övrigt vetenskapligt)
  • 35.
    Mueller, Urs
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB.
    Mechanical behaviour of earthen materials: A comparison between earth block masonry, rammed earth and cob2014Ingår i: Construction and Building Materials, ISSN 0950-0618, E-ISSN 1879-0526, Vol. 61, s. 327-339Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Earth represents one of the oldest construction materials, which is still utilised both in developed and in developing countries. In this paper a comparison of the mechanical performance of structural elements built in three basic techniques, earth block (adobe) masonry, rammed earth and cob, is presented. In order to gain better knowledge on the structural behaviour under static loads an extensive compression and diagonal compression (shear) test campaign was performed. First compression results showed brittle mechanical behaviour in the case of earth block masonry and rammed earth elements, whereas cob exhibited a very different stress-strain pattern: cob can deform beyond the elastic range with a gradual drop in capacity. Despite its low compressive strength, cob thus presents a relatively good performance within the earthen material range as far as shear behaviour is concerned. The data here reported represents a base for a further investigation on the dynamic behaviour of the three materials considered. The study was carried out within the framework of the project NIKER funded by the European Commission dealing with improving immovable Cultural Heritage assets against the risk of earthquakes.

  • 36.
    Mueller, Urs
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    The mineralogical composition of sandstone and its effect on sulphur dioxide deposition2008Ingår i: Materiales de Construcción, Vol. 58, nr 289-290, s. 81-95Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Air pollutants often accelerate stone deterioration in historical buildings and monuments in urban areas. The pollutants are themselves the products of fossil fuel combustion and intensive farming. While this trend seems to have been curbed by strict emission laws in the European Union, in most developing and emerging countries air pollution is an ongoing process due to increasing energy needs and vehicle traffic. Many factors condition natural stone behaviour with respect to gaseous pollutants. Two of the more prominent of such factors are the composition of the atmosphere and the type of stone. Due to their porosity, sandstones are particularly vulnerable to air pollutant attack. Many of the reactions between non-carbonaceous sandstones and these gases are not well understood, however. The present study aimed to acquire an understanding of the processes and factors governing sandstone behaviour when exposed to sulphur dioxide. Seven different sandstones from southern and eastern Germany were analyzed for the study. The binder composition of the stones varied significantly. They also exhibited completely different behaviour in connection with SO 2 sorption. Interestingly, while the amount of SO 2 deposited was unrelated to the specific surface area of the sandstones, this parameter was closely correlated to the iron oxide content. Iron oxide phases are believed to act as a catalyst in the oxidation of SO 2 to SO 3 . The type and amount of clay mineral, in turn, was found to have no significant impact on initial SO 2 deposition in sandstones.

  • 37.
    Mueller, Urs
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB.
    Lundgren, Monica
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB.
    Cement med tillsatsmaterial och risken för ASR i betong2014Ingår i: CBI-nytt, ISSN 0349-2060, nr 2, s. 5-Artikel i tidskrift (Övrigt vetenskapligt)
  • 38.
    Mueller, Urs
    et al.
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Lundgren, Monica
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Babaahmadi, Arezou
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Hydration of concrete binders blended with ground granulated blast furnace slag, fly ash and metakaolin2017Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    Rapporten beskriver en studie om inverkan av tillsatsmaterial (SCM) som mald granulerad masugnslagg, kiselhaltig flygaska och metakaolin på hydratationsförloppet hos cementpastor med sammansatta bindemedel, dvs en blandning av cement och en av dessa SCM.Studien undersökte den tidiga värmeutvecklingen, vilka cementhydratfaser som utvecklas vid olika ålder, hållfasthetsutvecklingen, förändringarna i porositet och porstorlekar, porvattnets OH-koncentration och utvecklingen av mikrostruktur och mikrokemi i cementpastan, beroende bindemedlets sammansättning.Studien visar att samtliga tillsatsmaterial (SCM) påverkar porstorleksfördelningen i cementpastan. Jämfört med en referenspasta med enbart cement, sker i cementpastor med blandcement (cement plus SCM) en ändring mot finare porstorlekar, dvs mindre pordiameter, ju högre andelen SCM i blandningen är. Den totala porositeten beror på vilken typ av SCM som används i blandningen. Slagg visade tendensen att leda till minskad total porositet med ökande slagghalt. Med flygaska ökade däremot den totala porositeten med ökande halt flygaska.Hållfastheten som utvecklas hos bruk med bindemedel med slagg och flygaska är lägre än den hos referensbruk med enbart Portland cement, under de första 28 dygnen. Efter 28 dygn märks däremot en mer markant hållfasthetsutveckling jämfört med referensbruket, i synnerhet hos bruk med flygaska. Med metakaolin noterades en markant ökning av hållfastheten redan under de första dygnen, men hållfasthetsutvecklingen fortsatte därefter i samma takt som (parallellt med) referensbruket.Aluminiumhaltiga SCM leder vid hydratation till bildning av hydratfaser av typen AFm.AFm-faser bidrar till ökad kloridbindning i cementpastan, en fördel för betong som utsätts för t ex havsvatten eller avisningssalter på vintervägar. I synnerhet metakaolin och flygaska, tack vare den höga aluminiumhalten, leder till cementhydrater av typen AFm, samtidigt som de även ökar aluminiumhalten i kalciumsilikathydraten (C-S-H-faser).

  • 39.
    Mueller, Urs
    et al.
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Lundgren, Monica
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Malaga, Katarina
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Development of pore structure and hydrate phases of binder pastes blended with slag, fly ash and metakaolin – A comparison2015Ingår i: ICCC 2015 Beijing: The 14th International Congress on the Chemistry of Cement, 2015Konferensbidrag (Refereegranskat)
    Abstract [en]

    Blended binder systems in concrete have been in use for many years. However, over the recent discussions on the sustainability of cement and concrete the topic became of paramount importance for the construction industry. In Sweden blended binder systems in concrete were applied fairly recently and supplementary cementitious materials (SCM) were not used largely before. In Sweden over the last 30 years engineering structures were built, with exceptions, with a low alkali, sulfate resistant Portland cement due to domestic requirements. Therefore, in context to blended binder systems durability is a major point being discussed. Most interest lays in the resistance towards frost, carbonation and chloride penetration and the experience with blended systems was limited. It is therefore the goal of this study to investigate blended binder systems over a longer hydration period of up to two years in context to durability. The results presented here will focus on the porosity and hydrate phase development within the first 90 days of hydration. In this study in total 9 different binder blends were studied. The blends included different replacement levels with granulated blast furnace slag from a Swedish producer, fly ash from a Danish power plant and commercially available metakaolin. The matrix included also one set of factory-blended cements (with interground fly ash and slag). The pore structure was investigated by mercury intrusion porosimetry (MIP), phase development by powder x-ray diffraction (XRD). The results are based on the evaluation of binder paste samples. Compared to a reference series consisting of a CEM I the slag containing series showed a continuous decrease of the total pore volume with increasing slag content over 90 days of hydration. The phase development showed a constant increase in monosulfate and hydrotalcite. The amount of these phases increased with increasing slag content. Notable was consumption of C4AF, which increased with the amount of slag and a decrease of C2S reaction. Compared to the reference Portland cement paste the fly ash containing pastes showed increased total pore volumes when the fly ash was just added. For the cement paste with interground fly ash the porosity development was the same as for the reference paste. The phase development for these series showed up to 28 days of hydration formation of ettringite, hemicarbonate and monocarbonate. After 91 days monosulfate was dominating and the amount of hemicarbonate was decreasing. The paste series with 15 % metakaolin showed a strong decrease in total pore volume compared to the reference series within 2 days. Afterwards the pore volume almost leveled to a constant value. The hydration phases included in the beginning large amounts of monosulfate, ettringite and hemicarbonate but changed after 91 days in favor to ettringite and monocarbonate. The metakaolin blend showed the lowest amounts of portlandite in all series, indicating a strong pozzolanic reactivity. The different hydrate phases, in particular AFm phases can help to explain a different behavior towards, e.g. chloride binding. The pore structure development has a large impact not only on strength development but also for ion and moisture transport as well as for carbonation in all series.

  • 40.
    Mueller, Urs
    et al.
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Malaga, Katarina
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Influence of hydrophobicity and oleophobicity on cleaning graffiti on concrete panels and natural stones2012Ingår i: Concrete Repair, Rehabilitation and Retrofitting III (ICCRRR), TAYLOR and FRANCIS GROUP, LONDON, UK , 2012, s. 269-275Konferensbidrag (Refereegranskat)
    Abstract [en]

    Anti-Graffiti Systems (AGS) are meant to make the cleaning process more efficient by inserting a layer between the paint and the substrate. This layer can have a low surface energy thus make it difficult for the paint to stick to the substrate or it may be easily removed together with the paint. This paper is presenting results from a study of how hydrophobicity and oleophobicity influence the cleaning efficiency of graffiti paints from concrete and natural stones. The results demonstrated that high hydrophobicity and high oleophobicity are not guaranteeing satisfying cleaning effects. The physical properties of a substrate in combination with the characteristics of the AGS layer decide about the cleaning effect.

  • 41.
    Mueller, Urs
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB, Betong & Berg.
    Miccoli, Lorenzo
    BAM Federal Institute for Materials Research and Testing, Germany.
    Fontana, Patrick
    BAM Federal Institute for Materials Research and Testing, Germany.
    Development of a lime based grout for cracks repair in earthen constructions2016Ingår i: Construction and Building Materials, ISSN 0950-0618, E-ISSN 1879-0526, Vol. 110, s. 323-332Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The study presents the results from the development of a grouting material based on hydrated lime with addition of pozzolana, which is referred to as hydraulic lime, suitable for the repair of cracks in a variety of earthen building techniques. The goal was to develop a material also compatible with earthen structures exposed to dynamic loads. The grouting mortar was designed to be adaptable in strength properties and at the same time to have sufficient robustness for preparation and use on the construction site. Results showed a satisfactory performance of the grout concerning fresh and hardened mortar properties as well as injectability.

  • 42.
    Mueller, Urs
    et al.
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Rübner, Katrin
    The microstructure of concrete made with municipal waste incinerator bottom ash as an aggregate component2006Ingår i: Cement and Concrete Research, Vol. 36, nr 8, s. 1434-1443Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The interaction of municipal solid waste incinerator bottom ash (MSWI bottom ash), when utilized as an aggregate in concrete, with the cement matrix was investigated. The most prominent reaction observed in lab and field concrete was the formation of aluminium hydroxide and the release of hydrogen gas from aluminium grains reacting in the alkaline environment. The expansive aluminium reaction was identified as a main cause of extensive spalling on the concrete surface. Due to the higher content of bottle glass as part of the ash, in all samples, reaction products of an alkali-silica reaction (ASR) could be observed as well. However, damage due to ASR were less severe than those caused by the aluminium reaction. The expansion rates were low and only a few of the lab samples showed cracking. Microstructural analysis of the samples indicated clearly that a large quantity of the alkali-silica gel which was formed was accommodated in the pores and voids without exerting any strain on the material.

  • 43.
    Mueller, Urs
    et al.
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Schlegel, Moriz-Caspar
    Emmerling, Franziska
    Malaga, Katarina
    Novel techniques for studying damage mechanisms of cementitious matrices affected by sulphate attack2012Ingår i: fib symposium Concrete Structures for Sustainable Community / [ed] Bager, D.H., Silfwerbrand, J., 2012, s. 267-270Konferensbidrag (Refereegranskat)
  • 44.
    Mueller, Urs
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB.
    Selander, Anders
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB.
    Nytt Ramprogram på CBI - Beständighet och hydratation2013Ingår i: CBI-nytt, ISSN 0349-2060, nr 2, s. 3-4, 13Artikel i tidskrift (Övrigt vetenskapligt)
  • 45.
    Mueller, Urs
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB.
    von Weschpfennig, Dieter
    Anti-Graffiti-Systeme auf Mauerwerk im Bereich der Bundesfernstraßen2011Ingår i: Bautechnik, ISSN 0932-8351, Vol. 88, nr 7, s. 443–450-Artikel i tidskrift (Övrigt vetenskapligt)
  • 46.
    Mueller, Urs
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB.
    Williams Portal, Natalie
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB.
    Chozas, Valle
    ACCIONA, Spain.
    Flansbjer, Mathias
    RISE., SP – Sveriges Tekniska Forskningsinstitut.
    Larraza, Inigo
    ACCIONA, Spain.
    da Silva, Nelson
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB.
    Malaga, Katarina
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB.
    Reactive powder concrete for facade elements: A sustainable approach2016Ingår i: Journal of Facade Design and Engineering, ISSN 2213-302X, Vol. 4, nr 1-2, s. 53-66Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Reactive powder concrete (RPC) is a fairly novel material with extraordinary strength and durability properties. Due to these properties, it is increasingly being utilized for external fa¸cade cladding thus enabling a considerable reduction in the thickness of concrete elements. Commercial RPC formulations on the market are usually expensive and less sustainable due to high cement clinker contents. In this study, improved RPC formulations with higher amounts of supplementary cementitious materials (SCMs) were developed. The formulations were combined with different types of reinforcements ranging from steel fibres to fibre textile grids primarily to enhance the ductility and tensile strength of the composite material. The results showed that even with clinker replacement levels of up to ca. 40% of the total binder amount, a satisfactory mechanical performance of the RPC mixes could still be achieved. A fairly steep strength gain rendered heat treatment unnecessary. The materials displayed good flow properties and a reasonably short initial setting time. The incorporation of carbon textile fibre grids proved to be highly effective in improving the post cracking behaviour of the RPC. The results validated a more sustainable approach for RPC applied to thin fa¸cade elements. 

  • 47.
    Mueller, Urs
    et al.
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Williams Portal, Natalie
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Flansbjer, Mathias
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Malaga, Katarina
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Textile Reinforced Reactive Powder Concrete and its Application for Facades2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    Reactive powder concrete (RPC) is a fairly novel material with extraordinary strength and durability properties. Due to these properties, it is increasingly being utilized also for external facade cladding thus enabling a considerable reduction in the thickness of concrete elements. Commercial RPC formulations on the market have drawbacks in terms of sustainability due to their high clinker content and heat curing which is often applied to increase final strength and material density. The presented study focusses on improved formulations with higher replacement levels of cement clinker by supplementary cementitious materials (SCMs). One different mix formulation was designed and tested in terms of mechanical properties. The formulation was combined with carbon textile reinforcements primarily to enhance the flexural and tensile behavior of the material. The results showed that even with clinker replacement levels of up to 33 % of the total binder amount, a satisfactory mechanical performance of the RPC mix could still be achieved. Fairly steep strength gains rendered heat treatment unnecessary. The incorporation of carbon textile fiber grids proved to be effective in improving the post peak performance of the RPC. However, their performance depended strongly on the bond between the carbon grid and the RPC. Higher moister contents in the concrete proved to reduce the bond strength between the carbon textile and the cement paste. This is maybe less relevant for facades but structural elements with textile reinforcement and RPC might perform less well in completely submerged environment.

  • 48.
    Mueller, Urs
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB.
    Ziegert, C
    Eigenschaften industrieller lehmbauprodukte für den mauerwerksbau und verhalten von lehmsteinmauerwerk2012Ingår i: Masonry, ISSN 1432-3427, E-ISSN 1437-1022, Vol. 16, nr 1, s. 17-28Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [de]

    Properties of industrially produced earthen building products for masonry and behaviour of earth block masonry. The contribution gives an overview of the properties of industrially produced earthen building products for masonry. In the meantime the quality of the industrial production of this group of building materials reached a level similar to that of other products for construction. Earth plasters exist as plasters for universal, one or multi layer applications or as lower, upper or finish plasters. Earth blocks are provided in different sizes and with different perforations. The mechanical properties of different earth block types are signified by compressive strength of up to 11 N/mm2 but are typically in a range between 2 and 5 N/mm2. A critical point is the correlation of the strength of earthen materials with their moisture content. Results from earth blocks showed that in a relative humidity window between 40 and 70 % rh the compressive strength of earth blocks is fairly constant. Masonry made from earth block and earth mortar exhibited compressive strength and elastic modules similar to masonry made with aerated autoclaved concrete blocks. The shear strength of earth block masonry, however, is fairly low, due to the weak bond between earth block and earth mortar.

  • 49. Schlegel, M C
    et al.
    Mueller, Urs
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB.
    Spatially resolved investigation of complex multi-phase systems using μxRF, SEM-EDX and high resolution SyXRD2013Ingår i: Cement & Concrete Composites, ISSN 0958-9465, E-ISSN 1873-393X, Vol. 37, nr 1, s. 241-245Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Spatially resolved analysis of complex multi-phase systems can be validated through different analytical methods. This study compares investigations by scanning electron microscopy coupled with energy dispersive X-ray fluorescence analysis and high resolution X-ray diffraction. The studied sulfate attacked cement paste containing fly ashes consists of different interacting crystalline and amorphous phases. The complementary methods revealed in detail changes in phase composition due to the chemical attack. The advantages and disadvantages of both methods are discussed and suggestions are given for combining them with additional methods to maximize the information content.

  • 50.
    Silva, Nelson
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB, Betong & Berg.
    Mueller, Urs
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB, Betong & Berg.
    Malaga, Katarina
    RISE., SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB.
    Hallingberg, Per
    Aercrete Technology AB, Sweden.
    Cederqvist, Christer
    Aercrete Technology AB, Sweden.
    Foam concrete-aerogel composite for thermal insulation in lightweight sandwich2015Ingår i: Concrete 2015: Proceedings of the 27th Biennial National Conference of the Concrete Institute of Australia in conjunction with the 69th RILEM Week "Construction Innovations, Research into Practice", Institute of Australia , 2015, s. 1355-1362Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper describes the initial steps towards the development of a foam concrete-aerogelcomposite for thermal insulation in lightweight sandwich façade elements. Fire safety is an important issuepertaining insulation materials. Therefore, the need for low-density inorganic, non-flammable materials israpidly increasing. Foam concrete is a lightweight material with good thermal characteristics; densities aslow as 400 kg/m3 and thermal conductivities as low as 100 mW/m·K can easily be achieved. The mainadvantage when compared to typical inorganic insulations (e.g. autoclaved aerated concrete or mineralwool) is that foam concrete has a much lower embodied energy, in particular due to the simplicity of themanufacturing process. However, in order to be competitive as an effective insulation material, thethermal conductivity needs to be drastically reduced which can be achieved by reducing the density andby incorporating silica aerogels (both measures affecting the compressive strength).

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