Im 3 2017 nl

2017 volume 3

INNOVATIVE MATERIALS

3D printing cellulose World’s first 3D-printed reinforced concrete bridge Materials 2017 Composites improve earthquake resistance in buildings Glass bridge Lina: world’s first biobased car

I N T E R N A T I O N A L

E D I T I O N

CONTENT About Innovatieve Materialen (Innovative Materials) is a digital, independent magazine about material innovation in the fields of engineering, construction (buildings, infrastructure and industrial) and industrial design.

Innovatieve Materialen is published in a digital format, although there is a printed edition with a small circulation. Digital, because interactive information is attached in the form of articles, papers, videos and links to expand the information available.

Scope The digital edition is sent to engineers, scientists, students, designers, decision makers, innovators, suppliers and appliers working in civil engineering, construction, building, architecture, design, government and industry (both manufacturing industry and end users).

Innovatieve Materialen has entered partnerships with several intermediate organisations and universities, all active in the field of material innovation.

More information (in Dutch): www.innovatievematerialen.nl>

Publisher

1 News 12 3D-printing cellulose

Both the Swiss Empa and the American MIT developed separately from each other a method of printing with cellulose.

12 World’s first 3D printed reinforced concrete bridge

The printing of concrete for the 3D-printed bridge has begun. On June 16th the Built Environment department’s concrete printer started printing the world’s first 3D printed reinforced, pre-stressed concrete bridge. The cycle bridge will be part of a new section of ring road around Gemert in which the BAM Infra construction company is using innovative techniques.

18 Materials 2017

On May 31th and June 1th, 2017, Mikrocentrum organized Materials 2017, at the NH Conference Center Koningshof in Veldhoven. ‘Materials’ is a yearly Tradefair & Congress on material innovation and technology, organised by Mikrocentrum.

This year, the organization has chosen a concept based on four building blocks for solutions to material challenges: (new) materials, material analysis, superficial techniques and connection methods.

22 Composites improve earthquake resistance in buildings

A research team from West Virginia University (WVU) has developed a system making use of composite materials that could improve earthquake resistance in buildings. According to WVU professor Hota GangaRao and Praveen Majjigapu, a PhD student in civil engineering, the system could increase the strength and endurance of structures in earthquakes, hurricanes, tornadoes and other large blasts.

24 Glass bridge

Researchers from the faculties of Architecture and the Built Environment and Civil Engineering and Geosciences of TU Delft are jointly developing a glass bridge to demonstrate that glass is very suitable for building structures. A bridge is a good way to demonstrate this material’s loadbearing capacity and safety. It is sustainable (made from sand, infinitely recyclable) and durable (does not corrode, rust or rot).

However, people do not yet trust in the strength of glass. A site has been assigned for the structure at the Green Village on the TU Delft campus.

SJP Uitgevers Postbus 861 4200 AW Gorinchem tel. +31 183 66 08 08 info@innovatievematerialen.nl

Editor

Gerard van Nifterik

Advertizing & sponsoring

Drs. Petra Schoonebeek

28 Lina: world’s first biobased car

A research team from West Virginia University (WVU) has developed a system making use of composite materials that could improve earthquake resistance in buildings. According to WVU professor Hota GangaRao and Praveen Majjigapu, a PhD student in civil engineering, the system could increase the strength and endurance of structures in earthquakes, hurricanes, tornadoes and other large blasts.

NEWS

‘Every surface solar’ A research team of The University of Melbourne developed a new generation of organic photovoltaics (OPVs), printable, lightweight, flexible solar cells, so pliable they can turn any surface into a solar array - from buildings, to vehicles or even clothing. According to dr David Jones, Senior Research Associate and Research Group Leader this new solar panel can be printed on a standard commercial printer, and then rolled up and taken with you.

It now features a new kind of high performance light-harvesting material with unusual crystallisation, which aligns its molecules to improve performance.

OPVs can be produced en masse at low cost, simply by being printed on large

plastic sheets, using standard commercial printers.

‘Quite often flexible, lightweight solar arrays are appealing to retro fit roofs where silicon cells would be too heavy,’ says Dr David Jones on the University of Melbourne-website. ‘They could also work really well as transportable power sources on awnings, shade cloths or umbrellas.’

There is even scope for using window glass to generate solar power, opening up massive areas of building surfaces for energy production. The secret here is to use the windows themselves to direct the light they harvest to OPVs attached to the window edges.

Video

OPVs also have the potential to perform dual environmental functions, like covering surfaces of lakes or other large expanses to water to help prevent evaporation while simultaneously generating energy. Another is as temporary covers on grain silos in central Australia, to prevent overheating while powering the fans that stop the grain from sweating.

The cells’ initial vulnerability to photochemical degradation - or sun damage - has been overcome through new materials and encapsulation technologies developed with partners CSIRO. And most recently, the team’s discovery of new high performance materials has improved the printing process.

The team now needs to scale the printing process to prove its commercial viability, before it is ready for a private company to take to market - a process that should only take a couple of years, according to Dr Jones.

Dr David Jones, Senior Research Associate and Research Group Leader (left) and dr. Wallace Wong, with a printed OVP sheet (watch video link)

University of Melbourne>

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NEWS

Mycelium lab: Mushroom products for building On June 9th the Center of Expertise Biobased Economy (CoE BBE) and the SPARK Innovation Campaign opened a laboratory for research on the application of fungi in the construction industry. In this so called Mycelium Lab research is being carried out on the application of fungi in the construction industry.

Mycelium is the vegetative part of a fungus, consisting of a mass of branching, thread-like hyphae.

It’s the residual product from the mushroom and oyster mushroom culture.

Mycelium, with its natural origin, belongs to one of the biobased building materials where research is conducted

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at the CoE BBE, a collaboration between Avans University and HZ University of Applied Sciences.

In the Mycelium Lab at the SPARK site at Rosmalen, fungi are grown on different substrates such as sawdust or straw to develop mycelial composites. In this material, mycelium acts as a binder to pack loose particles together. By means of molds it is possible to grow products that may be usefull in the construction industry.

In this research project, students from different courses work together, including Architecture, Engineering, Commercial Economics, Environmental Science for Sustainable Energy and Technology,

Chemistry and Chemical Technology. In addition to developing the material, it is also extensively tested for properties such as strength, thermal insulation and water resistance.

More at CoEBBE (Dutch)>

NEWS

Hardened titanium opens up a world of opportunities Researchers of DTU (Danmarks Tekniske Universitet) have developed a new patentable and simple method to harden the surface of the lightweight metal titanium and thus multiply its strength. Titanium is an attractive material due to its lightness. The material finds widespread use in not least the aerospace industry, but also auto parts and professional sports equipment such as race bikes and golf clubs are made of titanium or titanium alloys. In addition, most implants are manufactured from metal, as titanium offers a high degree of biocompatibility. However, titanium is a soft material, which means that it is not particularly durable with a surface susceptible to scratches or damage.

DTU developed a method for hardening the surface based on gases, which can penetrate all small cavities and holes in the material and thus make it strong. It is a mixture of, for example, carbon and oxygen that is used for the treatment and which adds the extra strength.

The two scientists involved - Morten Stendahl Jellesen and Thomas Christiansen, both senior researcher at DTU

Surface-hardened ‘pulley wheels’ in 3D printed titanium alloy (printed by the Technological Institute in Aarhus); after two different ‘DTU hardening processes’

- are well aware that the new hardening method may prove very successful due to the increasingly large industrial use of 3D metal printing in the coming years.

They are in no doubt that the large development in 3D printing for industrial use will make the use of titanium even more attractive. ‘When you can then treat the surface using our method,’ Christiansen

said, ‘and the material becomes up to ten times harder, titanium suddenly becomes an extremely interesting material in many different contexts.’ www.dtu.dk>

The microstructure of the surface-hardened pulley wheel seen in a microscope (cross-section of the component). Left: before hardening. Right: after hardening. In this case, the surface hardness has been increased five times. Images from ongoing MSc project; Emilie H. Valente

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NEWS

INNOVATIEVE MATERIALEN 1 2017

Voeg informatie toe aan de Kennisbank Biobased Bouwen De Biobased Economy speelt een belangrijke rol in de duurzame ontwikkeling van Nederland en biedt nieuwe kansen voor het bedrijfsleven. Via de kennisbank kunt u kennis vergaren en delen over de beschikbaarheid en toepassingsmogelijkheden van biobased materialen, producten en bouwconcepten. Samen versterken we zo de biobased economie.

Ruim dertig partijen in de bouwsector ondertekenden de green deal biobased bouwen. Deze producenten, architecten, adviseurs en kennisinstellingen delen hun kennis rond kansrijke mogelijkheden van biobased bouwen. Ook de ministeries van Binnenlandse Zaken (Wonen en Rijksdienst), Economische Zaken, en Infrastructuur en Milieu ondersteunen de green deal.

Bouw ook mee aan de biobased economie en voeg uw project- of productbeschrijvingen toe aan deze kennisbank.

Kijk op www.biobasedbouwen.nl voor meer informatie> 4 | INNOVATIVE MATERIALS 3 2017

NEWS

The construction of the Crystal Houses façade: challenges and innovations

A year ago the Crystal Houses glass brick facade (MVRDV, Gietermans & Van Dijk) at the P.C. Hooftstraat in Amsterdam was revealed. The Glass & Transparency Research Group (TU Delft) was involved in the development and testing of the facade and the daily supervision of the construction. The involved TU Delft researchers are Prof. Rob Nijsse, Dr. Fred Veer, ir. Faidra Oikonomopoulou and ir.

Telesilla Bristogianni. The results were

recently published in the paper: ‘The construction of the Crystal Houses façade: challenges and innovations.’

The glass brick façade has been designed and engineered to reproduce the original brick façade of a former townhouse in Amsterdam. Based on the original design the resulting façade comprises more than 6500 solid glass bricks, reinterpreting the traditional brick pattern,

and elaborated cast glass elements for the replication of the window and door frames.

To achieve unhindered transparency, the 10 by 12 m glass block façade has to be self-supporting. Previous experimental work by Oikonomopoulou et al. concluded that it was necessary to use a clear, UV-curing adhesive of high stiffness as bonding material. Experimental work on prototype elements indicated that the desired monolithic structural performance of the glass masonry system, as well as a homogeneous visual result, are only achieved when the selected adhesive is applied in a 0.2 - 0.3 mm thick layer.

The nearly zero thickness of the adhesive together with the request for unimpeded transparency introduced numerous engineering challenges. These include the production of highly accurate glass bricks and the homogeneous application of the adhesive to achieve the construction of the entire façade with remarkably tight allowable tolerances.

This paper presents the main challenges confronted during the construction of the novel façade and records the innovative solutions implemented, from the casting of the glass units to the completion of the façade. Based on the conclusions of the research and the technical experience gained by the realization of the project, recommendations are made on the further improvement of the presented glass masonry system towards future applications.

The full article online>

Video: Building the Crystal Houses Glass & Transparency Research Group - TU Delft

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NEWS

SI-Modular: Sustainable building system with timber I-beams the precise milling, no assembly errors arise and the construction is very stable.

Only a hammer is necessary for the assembly.

Metsä Wood>

Video

Architect Hans-Ludwig Stell from Münster, Germany, has developed a sophisticated modular system for one and two-storey house construction.

This quick an easy timber construction, SI-Modular, is based on Metsä Wood´s I-beam Finnjoist.

Hans-Ludwig Stell, the managing partner of the Stellinnovation GmbH, was asked to develop a house type for use in development-aid that could be assembled as simply as possible. The SI-Modular system enables the houses to be constructed completely from timber without

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screws, by simply using interlocking connections in the installation.

The construction of timber I-beams is similar to that of steel I-profiles. Due to the high load capacity, the I-beams are used for the walls, floors and roof. The I-beams are fixed to the horizontal rails which are anchored to the floor plate.

When erecting the walls, the transversely running beams are visible. The individual timber components are connected using precisely interlocking connections.

Due to the stability of the I-beams and

Hét expertisecentrum voor materiaalkarakterisering.

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Wij helpen u graag verder met onderzoek en analyse van uw innovatieve materialen.

Bel ons op 026 3845600 of mail info@tcki.nl www.tcki.nl

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09-05-17 13:19

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NEWS

‘Baubotanic’ Living plant constructions? Prof. Ferdinand Ludwig from the Professorship for Green Technologies in Landscape Architecture and Daniel Schönle (both Technical University of Munich (TUM) Department of Architecture) have realized some socalled 'baubotanical' projects. Recently TUM released on her website the YouTube shortfilm ‘Baubotanik shapes living tree branches into building facades’ by Kirsten Dirksen, wich explains their work and the principles of natural-technical construction methods.

The idea is to use biological processes and structures to develop innovative technical solutions and new approaches in architecture and landscape design. Recent years prof. Ludwig has developped several architectural concepts in which plants play a decisive role.

Ludwig’s first biodesigned structure was the baubotanik footbridge planted in 2005. He thinks his Baubotanik methods can scale to buildings as high as a tree can grow (about 30 meters). ‘We can build a house that is a tree at the same time,’ Ludwig says. ‘A house tree; tree house.’

TUM>

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Video

BERICHTEN NEWS

Noise barrier with integrated solar cells

Along the N470 road in the Dutch town of Pijnacker-Nootdorp (between Rotterdam and The Hague), BAM Infra is preparing to build a noise barrier with integrated solar cells that will generate 30 megawatt hours of electricity a year.

The barrier, designed and built by BAM Infra, is the first to be built.

After the summer, Pijnacker-Nootdorp will see the completion of final houses in the newly developed Keijzershof area, adjacent to the N470 roadway. In order

to create the best possible living conditions for the area’s residents, the municipality has ordered a 480-metre-long and 2.5-metre-high noise barrier.

The noise barrier is easy to maintain, weather proof and fully vandalism resistant. To protect the solar cells from the impact of loose road chippings, BAM Infra’s design places the cells between two extra thick layers of glass (8 millimetres each).

After completion of the noise barrier,

BAM Infra will have the responsibility to generate an average of 30 megawatt hours a year - enough to power ten households - for a period of ten years.

Grid operator will channel the generated energy into the public grid. Completion has been scheduled for mid November 2017.

BAM Infra>

University of Twente opens 3D print lab June, 14th the University of Twente has opened its own 3D printing facility: the Rapid Prototyping Lab. 3D printing is being increasingly used to quickly try out ideas and to produce complex shapes. For example, researchers at the University of Twente can use the Rapid Prototyping Lab to print special parts for the experimental setups used in their research. The Rapid Prototyping Lab is also being used for educational purposes. In addition, research is being carried out into new ways of doing 3D printing, involving the combination of different materials and techniques, for example.

Opportunities

According to the Professor of Biomechanical Engineering, Prof. Bart Koop-

man, the Rapid Prototyping Lab offers a wealth of new opportunities. ‘For everyday users, this lab offers an extra degree of quality that standard printers cannot provide. For example, it can produce prints that are also capable of bearing considerable mechanical loads.

In addition, its educational value lies in the wide range of printing techniques that it offers. In terms of research, there are plans to look into the printing of composites and rubbery materials. For instance, some researchers want to print a complete artificial heart, to test valves or support pumps. We are also keen to combine printing with post-processing techniques – in a single device – to create a more fully-fledged production machine. We also have plans to expand

the lab’s capabilities by installing metal printers.’

The lab is open to all research groups and students at the University of Twente. ‘We think it’s very important for the lab to be a shared facility,’ says Bart Koopman. ‘Teams of students like Solar Team Twente and Green Team Twente are already making full use of the facilities. We also have a direct link with the University of Twente’s DesignLab. The use of the lab and its facilities is currently being integrated into the Mechanical Engineering and Industrial Design programmes.’

More at www.utwente.nl/rpl>

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NEWS

(Image: Block Research Group)

Modern construction using long forgotten techniques Researchers at ETH Zurich’s Department of Architecture (D-ARCH) have developed a concrete floor system that does not require steel reinforcement and is 70 percent lighter than conventional concrete floors. Moreover, the elements help to protect the environment as they require less concrete, whose production gives rise to large quantities of CO2.

Weight reduction is possible because, instead of being flat, the slabs are arched like the vaulted ceilings of Gothic cathedrals. Simply by virtue of their shape, they can support very heavy loads and so do not need to be strengthened with reinforcing steel.

was brought to the USA in the late 19th century by the Spanish architect Rafael Guastavino, who reinforced his brick

Historical

According to the ETH-researchers their design is based on historical construction principles and techniques that have since been forgotten. To this end, the researchers analysed structures in various styles, including the Catalan vault.

This traditional construction method

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(Image: Block Research Group)

vaults with narrow vertical ribs on the upper side. These ribs serve to create a flat surface for the floor, and also provi-

NEWS NEST HiLo NEST is a modular research and demonstration platform for advanced and innovative building technologies in the heart of the Empa-Eawag campus (Empa is the leading Swiss institute on material science and technology). NEST was created in 2016 to accelerate the process of innovation in the building sector.

Part of the NEST-project is HiLo, a research & innovation unit in the domains of lightweight concrete construction and smart, adaptive building systems.

Video NEST: Virtual tour on EMPA TV

de the vault’s stability under asymmetric loading - that is, when the weight of people or objects is not distributed evenly throughout the room.

Pattern of lines

The ETH researchers adopted this principle of strengthening ribs for their concrete elements. Using specially developed computer software, they calculated how the ribs would need to be arranged to produce the optimum distribution of compression forces under loading, resulting in an intricate pattern of thin lines that converge at each of the corners.

The supports are connected by a set of steel ties that absorb the resulting horizontal forces - performing the same role as the flying buttresses that support the vaults in cathedrals. Stress tests have shown that it can withstand an asymmetric load of 4.2 tonnes, which is more than two and a half times what the applicable building codes in Switzerland stipulate.

the first time at HiLo the NEST research building in DĂźbendorf, east of Zurich.

3D printing

Until now, however, the elements were expensive to produce because they had to be cast in double-sided moulds that needed to match each other precisely.

The ETH-team therefore went one step further: to bring the production costs down, they produced the first elements using 3D printing - but instead of concrete, they used sand combined with a binder. These elements can withstand a load of 1.4 tonnes and so also comply with Swiss building standards.

ETH Zurich>

HiLo

The researchers will now test their innovative flooring slabs in practice for

Load tests show that the new type of floor fulfills Swiss construction standards (Image: Block Research Group)

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NEWS

3D printing with cellulose (1) Cellulose acetate ink For centuries, cellulose has formed the basis of the world’s most abundantly printed-on material: paper. Now, thanks to new research at MIT, it may also become an abundant material to print with.

Using cellulose as a material for additive manufacturing is not a new idea, and many researchers have attempted this but faced major obstacles. When heated, cellulose thermally decomposes before it becomes flowable, partly because of the hydrogen bonds that exist between the cellulose molecules. The intermolecular bonding also makes high-concentration cellulose solutions too viscous to easily extrude.

Instead, the MIT team chose to work with cellulose acetate, a material that is easily made from cellulose and is already widely produced and readily available.

Essentially, the number of hydrogen bonds in this material has been reduced by the acetate groups. Cellulose acetate can be dissolved in acetone and extruded through a nozzle. As the acetone quickly evaporates, the cellulose acetate solidifies in place. A subsequent optional treatment replaces the acetate groups and increases the strength of the printed parts.

According to the MIT researchers the strength and toughness of the parts, were greater than many commonly used materials for 3D printing, including acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA).

To demonstrate the chemical versatility of the production process, Pattinson and Hart added an extra dimension to the innovation. By adding a small amount of antimicrobial dye to the cellulose acetate ink, they 3D-printed a pair of surgical tweezers with antimicrobial functionality.

Because most existing extrusion based 3D printers rely on heating polymer to make it flow, their production speed is limited by the amount of heat that can be delivered to the polymer without damaging it. This room-temperature

cellulose process, which simply relies on evaporation of the acetone to solidify the part, could potentially be faster.

Cellulose acetate is already widely available as a commodity product. In bulk, the material is comparable in price to that of thermoplastics used for injection molding, and it’s much less expensive than the typical filament materials used for 3D printing, the researchers say. This, combined with the roomtemperature conditions of the process and the ability to functionalize cellulose in a variety of ways, could make it commercially attractive.

The paper was published earlier this year in Advanced Materials Technologies titled ‘Additive Manufacturing of Cellulosic Materials with Robust Mechanics and Antimicrobial Functionality’ (post doc Sebastian W. Pattinson en prof. A. John Hart).

MIT>

By adding a small amount of antimicrobial dye to the cellulose acetate ink, they 3-D-printed a pair of surgical tweezers with antimicrobial functionality

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NEWS

3D printing with cellulose (2) Inks from the woods the printing of implants or prostheses.

These possibilities are currently being investigated further at Empa, focusing on the further development of the materials and the printing method for other applications.

More at Empa>

Video

Like MIT, Empa attempted to use cellulose for 3D printing. According to the Empa-website reseraches succeeded in developing an environmentally friendly ink for 3D printing based on cellulose nanocrystals, so called CNC’s. Cellulose NanoCrystals CNC’s, are tiny rod-like structures, 120 nm long, with a diameter of 6.5 nm. They can be extracted from cellulose, along with lignin and hemicellulose, one of the main constituents of wood.

In order to produce 3D microstructured materials for composite applications, Empa researchers have been using a 3D printing method called ‘Direct Ink Writing’ (DIW). The advantage of DIW lies in the almost unlimited selection of materials available for inks. The cartridges can be filled with any kind of ink with differing compositions and these can then be printed directly and alternately.

The printer has one high and one low temperature cartridge.

The biggest challenge was optimizing the viscous elastic consistency of the CNC ink. It should be able to squeeze through the 3D printer nozzles. On the

other hand the ink must be thick enough so that the printed material stays ’in shape’ before drying or hardening, and doesn’t immediately melt out of shape again.

Ultimately the researchers developed a polymer based recipe that had a decisive advantage: after printing the material was hardened using UV radiation, which resulted in a composite material with according to Empa outstanding mechanical properties.

Empa thinks this cellulose ink may be of interest to, for example, the automobile industry or for packaging of any kind and certainly to biomedicine, especially in

Rod-like Cellulose NanoCrystals (CNC) approximately 120 nanometers long and 6.5 nanometers in diameter under the microscope (Image: Empa)

A jaw bone printed with the cellulose ink - the outstanding mechanical properties have promising potential uses in implants and other biomedical applications

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NEWS BERICHTEN

Aluminium facade

Earlier this year, the works on a retail complex, located in the city of Enschede, were completed. The facade was designed by BFAS. Two different types of panels have been designed especially for the project. On the corner of the street there are flat aluminum panels (60 mm thick) with oval perforations. A new technique is used for the other vertical cassettes; a pattern of diamond shape was cut out and rotated individually which creates a surprisingly 3D effect. At the moment, stone frames around the aluminum cassettes and panels are being mounted.

The final curved seven meter high glass wall at the corner will be placed soon.

(Photography: Joop van Reeken & Joost Koek) Source: BFAS>

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World’s first 3D printed reinforced concrete bridge The printing of concrete for the 3D printed bridge has begun. On June 16th the Built Environment department’s concrete printer started printing the world’s first 3D printed reinforced, pre-stressed concrete bridge. The cycle bridge will be part of a new section of ring road around Gemert in which the BAM Infra construction company is using innovative techniques.

One of the advantages of printing a bridge is that much less concrete is needed than in the conventional technique in which a mold is filled. By contrast, a printer deposits only the concrete where it is needed. This has benefits since in the production of cement a lot of CO2 is released and much less of this is needed for printed concrete. Another benefit lies in freedom of form: the printer can make any desired shape, and no wooden molding frames are needed.

An extra detail is that the researchers in the group of Theo Salet, professor of concrete construction, have succeeded in developing a process to also print the steel reinforcement at the same time. When laying a strip of concrete the concrete printer adds a steel cable so that the bridge is ‘pre-stressed’ in

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The 3D - printed b

order to no tensile stress can occur in the concrete, because this is something that concrete is not able to cope with adequately.

In recent months Theo Salet’s research group made an initial scale model (1:2) and tested its safety by subjecting it to a 2000 kg load. Now that the safety has been demonstrated, a start can be made on printing the concrete elements that will later be glued together to form a bridge.

It is expected that the bridge elements will be printed and ready this summer. In September the BAM construction com-

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INNOVATIVE MATERIALS 3 2017 pany will put the bridge in place in the Noord-Om, a new section of ring road around the village of Gemert, where the company is also using other new innovative building techniques. Others involved in the project are engineering firm Witteveen+Bos, the Province of Noord-Brabant, the municipality of Gemert-Bakel, Saint-Gobain Weber Beamix B.V., Dywidag-Systems International BV, Verhoeven Timmerfabriek and NV Bekaert SA.

Video: Koninklijke BAM Groep /Royal BAM Group Artist impression of the 3D printed bridge near Gemert (BAM)

bridge of Alcobendas The first 3D printed pedestrian bridge of Alcobendas is considered the first innovation of its kind in which civil engineers used the technology on a large scale. It was inaugurated last December 14 in the urban park of Castilla-La Mancha in Alcobendas, Madrid.

The Institute of Advanced Architecture of Catalonia (IAAC) was in charge of the architectural design of the bridge, which has a total length of 12 meters and a width of 1.75 meters and is printed in micro-reinforced concrete.

According to the IAAC the 3D printed bridge, which reflects the complexities of nature’s forms, was developed through parametric design, which allows to optimize the distribution of materials and minimize the amount of waste by recycling the raw material during

manufacture. The computational design also allows to maximize the structural performance, being able to dispose the material only where it is needed, with total freedom of forms.

The executive project, led by ACCIONA, was developed by a multidisciplinary team of architects, mechanical engineers, structural engineers and representatives of the municipal administration, among them Enrico Dini, an expert inventor of large-scale 3D manufacturing and IAAC collaborator.

IAAC>

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Materials 2017

On May 31th and June 1th, 2017, Mikrocentrum organized Materials 2017, at the NH Conference Center Koningshof in Veldhoven. ‘Materials’ is a yearly Tradefair & Congress on material innovation and technology, organised by Mikrocentrum. This year, the organization has chosen a concept based on four building blocks for solutions to material challenges: (new) materials, material analysis, superficial techniques and connection methods.

The aim of Materials is to connect material science with everyday practice.

But this year there was not just attention for materials. In material challenges, analysis techniques, surface treatments and connection methods also play an important part. Both the exhibition floor and the lecture program were built in their entirety on these four pillars.

Materials offered more than 40 dissertations this year, divided over the four building blocks. Remarkable highlight from the lecture program was the keynote provided by Peter Heideman, Architect AvB, StudioSK / Movares: ‘Design Process Changes by Computational Design.’

Peter Heideman told about the role of software in the design process and robotization of the making process. According to him, the roles in the design process are changing drastically. At the beginning of the design process, integral design parameters are determined (using an

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analogy with the integral recording of information via DNA in cell nuclei). In production, workflows expire and material is applied only where necessary. In the future, processes in the building column will look similar to the processes that are now normal in the automotive and aerospace industry, Heideman said.

With more than 85 exhibitors and more than 40 knowledge sessions Materials says to connect material science and

concrete application. In addition to the sessions, there were so-called ‘experience areas’ with live demos in the Analysis Pavilion, an exhibition of new materials in the Innovative Materials Pavilion and demonstrations of the latest technologies at the Materials Joining Exhibition.

The next edition of Materials 2018 - Trade Fair & Congress is scheduled for 30 and 31 May 2018, NH Conference Center Koningshof, Veldhoven. www.materials.nl>

Innovative Materials pavilion: Solid cast glass units Solid cast glass units are suggested for the restoration of the Lichtenberg Castle in Maastricht, to complete the missing parts of the monument. The components are designed in three different sizes, in respect to the existing construction technique and aesthetics of the original masonry. Aiming for a reversible system, the glass units are interlocking, ensuring the overall stability without necessitating permanent, adhesive connections. The exhibited 1:2 scale samples are kiln-cast at the TU Delft Glass Lab.

TU Delft Glass Transparency Research Group>

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Innovative Materials pavilion: 3D-printed architectural concrete

Innovative Materials pavilion: curved interlocking cast glass components

3D-concrete printing until now has been associated with cold, grey building shells, such as those made in China. Bruil now is taking the first steps in the building industry’s ‘3D-printing revolution by developing software with which the 3D-model of the architect can be easily converted into print paths.

With this innovation, the print process and end result can be simulated instantly, after which the printing can be immediately started.

The Glass Masonry Bridge designed for the TU Delft Green Village is composed by curved interlocking cast glass components, compressed together to form a stable arch. Inbetween the glass bricks, a transparent interlayer is placed, to avoid stress concentrations. Such dry-connections allow for the easy assembly and disassembly of the structure and favour the reuse and/or easy recycling of the individual components. The exhibited 1:2 scale samples are kiln-cast at the TU Delft Glass Lab.

Bruil BV, Ede. www.bruil.nl>

TU Delft Glass Transparency Research Group>

Innovatieve Materialen pavilion: Basalt stone products

Innovatieve Materialen pavilion: WasteBasedBricks

Basalt stone fibers are drawn with means of a catalyst from the melted basalt stone lava. The catalyst influences only the hardens behavior instead of becoming a igneous rock column you can draw fibers out of the lava. The fibers are called roving and are coiled up on bobins. From this stage all kind of products can be made.

WasteBasedBricks are building stones made from various types of waste, and then combined in different ways to create new colours, textures, shapes and sizes. All the products meet today’s industry requirements and can be used for both the interior and exterior of buildings.

Vulkan Europe: www.vulkan-europe.com>

StoneCycling: www.stonecycling.nl>

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INNOVATIVE MATERIALS 3 2017

Computational design and circulair building: prototypes of the 3D printed ‘Concrete Pavilion’ Computational design and the ability of computational thinking are increasingly becoming part of circular construction. In the 3D-model, value is created by adding parameters and wishes are translated into the future of structures. One of the most important currant developments in construction is the circular economy. This development has far-reaching impact on the entire chain. ‘Use’ is the new property.

Within Movares, a multidisciplinary department of computational design has been formed between the departments of Structural Design, Dynamics and StudioSK, with various companies and graduates connected. This collaboration resulted in the use of new software tools allows engineers to use material in construction as efficiently as possible, which benefits the durability of a construction. There is a lot of profit to be achieved, including in the context of CO2 reduction.

Peter Heideman, Architect AvB, StudioSK/Movares: ‘Design proces is changing by Computational Design’

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INNOVATIVE MATERIALS 3 2017

Hota GangaRao (left) and Praveen Majjigapu inspect structure after WVU lab test

Composites improve earthquake resistance in buildings A research team from West Virginia University (WVU) has developed a system making use of composite materials that could improve earthquake resistance in buildings. According to WVU professor Hota GangaRao and Praveen Majjigapu, a PhD student in civil engineering, the system could increase the strength and endurance of structures in earthquakes, hurricanes, tornadoes and other large blasts.

The team developed a three-piece system consists of filler modules (wedges), reinforcing dowels and composite materials. After the wedges are bonded to the joint, team members install steel bars through the wedges and into the concrete to reinforce and lock the pieces into place. Next the team cuts multiple sheets of composite material - fabric made of carbon or glass fibers bonded with a polymer resin - into a series of

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puzzle pieces that are wrapped around the concrete, adhered with additional resin and left to cure. Once the composite has hardened, the totality of dissimilar materials is bonded together and work as a single unit, stronger and more durable.

Simple

At first glance, a wedge nestled into a joint seems like an easy solution, but

‘the beauty of the system is its simplicity,’ GangaRao said on the WVU-website.

According to GangaRao, rehabilitation of old buildings is expensive and labour intensive, and an affordable solution will allow more buildings to be strengthened.

The system can work with structures made of various materials, such as concrete, timber and composites. The wedges can also be made of different

INNOVATIVE MATERIALS 3 2017 advanced materials depending on their application.

Aside from material, one of the most important characteristics of the wedge is its shape, which is meant to eliminate high-stress zones in the joint and depends on factors such as load, material and the configuration of the joint.

Testing for failure

The research team bonds filler modules - white, wedge-shaped pieces - to a concrete joint.

The scientists are testing their system to the point of failure, and they figured out how a column behaves under stress. But still they know little about what happens at the intersection of the two.

However, without the three-part system, GangaRao’s lab tests have shown failure under a 7-ton load. With the system, the team has been able to apply five to seven times that amount - nearly 50 tons - before failure. GangaRao will continue lab testing, but plans to begin field testing on towers, lattice structures and hydrostructures to record repeated performance of the retrofit in real-world applications. His goal is to provide maximum strength and endurance at very low cost, while also making it quick and easy to outfit buildings and bridges with a new system.

Ultimately, he thinks that the success of the system will rely on cooperation with industry, practicing engineers, construction companies, agencies, departments of transportation, cities, states and countries.

West Virginia University>

Applying composite material

Video: testing

Video: interview with WVU-professor Hota GangaRao

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INNOVATIVE MATERIALS 3 2017

Glass bridge

Researchers from the faculties of Architecture and the Built Environment and Civil Engineering and Geosciences of TU Delft are jointly developing a glass bridge to demonstrate that glass is very suitable for building structures. A bridge is a good way to demonstrate this material’s loadbearing capacity and safety. It is sustainable (made from sand, infinitely recyclable) and durable (does not corrode, rust or rot). However, people do not yet trust in the strength of glass. A site has been assigned for the structure at the Green Village on the TU Delft campus.

The Green Village is a terrain on the campus of the Delft University of Technology, where all kinds of technical, sustainability-related, features will find a home. Between the Green village and the campus, there is a fourteen meter wide canal over which a new bridge, 2.2 meters wide, has to be constructed. Since the department of Structural Design of the Faculty of Architecture of Delft University of Technology had a good working experience with an experimental façade, made from cast glass blocks, for the Chanel store in Amsterdam, it was decided that the same building material, massive cast glass blocks, will be used to construct a glass arch bridge for the Green Village.

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INNOVATIVE MATERIALS 3 2017

Sustainable

Glass is a good choice for a Green bridge, for glass is a very sustainable material; it is made from sand, it doesn’t corrode, and itis 100% recyclable without any loss of quality. Moreover, glass is transparent, a beautiful property that makes it shine and sparkle and adds an interesting esthetical value to the bridge.

Tension

To construct a glass arch bridge, a temporarily supporting structure is required.

For this purpose, a steel glass lenticular truss bridge was designed. The diagonals were glued together in a bundle of six massive 20 mm-diameter glass bars with UV hardening adhesive. In the middle, a hollow star shaped central bar exists,

through which a steel bar of a diameter of 8 mm was placed. To make a firm connection between this one steel bar and the six glass bars surrounding it, it was decided to pre-stress the steel bar and thus put a permanent compression load on the glass bars. The pre-stress force was chosen to be identical to the maximum possible tensile force in a diagonal.

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INNOVATIVE MATERIALS 3 2017 So, in reality, the glass will never be loaded in tension; a tensile stress situation is unfavourable for the material.

Temporary

Through the holes in the glass stones, the lengthened steel bar was positioned.

On top of the two completed trusses a corrugated steel plate was mounted that forms the basis of the walking platform of the bridge. This steel-glass lenticular truss bridge is temporary. In

the near future, after all the necessary tests will have been carried out in TU Delft, the final glass arch bridge will be constructed. This means that the cast glass stones of the glass arch will be placed directly on top of the corrugated steel plate. After the last stone is put in position, the arch will be completed, and the supports connected to the concrete foundation blocks of glass truss bridge will be lowered and recycled/reused at another position. What remains is a

shining, shimmering glass arch spanning the 14-meter canal.

Ate Snijder, Rob Nijsse, Telesilla Bristogianni, Joris Smits, Wan-Yun Alice Huang, Kees Baardolf, Christian Louter, Rafail Gkaidatzis, Fred Veer; Glass & Transparency Research Group, TU Delft

During a special event on May 15th 60 students performed several static and dynamic load bearing tests on the glass truss bridge

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INNOVATIVE MATERIALS 3 2017

The making of ...

The bridge was constructed entirely in the CiTG lab. After completion it was hoisted onto a truck, driven to the site, and hoisted in place by Zwatra Transport.

The video below shows the process of making the three structural glass components. The glass bundles were initially developed by Rob Nijsse, Faidra Oikonomoupoulou and Erik van den Broek.

The end connections have been redesigned for better looks and for introducing a prestressing tendon. By prestressing the glass bundles tensile stresses in the glass itself are avoided and the tensile stiffness of the overall diagonal is significantly increased. To guarantee the safety of the bridge all the glass diagonals have been proof loaded to 2.5 times the maximum expected load.

Glass wing

The glass connector blocks and the glass sheets for the wings have been waterjet cut by Alleswatersnijden.nl. The blocks were especially difficult because of their thickness of 65 mm but more so because a hole had to be cut at a tricky angle through the block. These unusual glass pieces were then stuck to the steel frame using a double sided acrylate tape.

The glass wings are completely made from waterjet cut glass. They consists of four layers of 6.6.2 annealed floatglass and have been glued together using UV hardening Delo glue.

The two sheets of glass in the middle are smaller doughnut shapes. Between the doughnuts are the channels that the stainless steel cables are run through.

The holes in the doughnuts are there to save weight and glue. The size of the holes has been optimised for decreasing amount of shear force that occurs along the height of the wing.

Construction of steel-glass lenticular truss bridge at CiTG lab TU Delft

Researcher Ate Snijder with a scale model of the bridge

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INNOVATIVE MATERIALS 3 2017

Lina

World’s first bio-based car A research team from West Virginia University (WVU) has developed a system making use of composite materials that could improve earthquake resistance in buildings. According to WVU professor Hota GangaRao and Praveen Majjigapu, a PhD student in civil engineering, the system could increase the strength and endurance of structures in earthquakes, hurricanes, tornadoes and other large blasts.

Unique to Lina is that her entire chassis, body and interior are made from bio‐ based materials.

Thanks to a weight of just 310 kilograms, the car is extremely efficient. The city car seats four people.

The bio-based car concept is a reaction on a trend towards lighter but energy-consuming materials. Since recent years, improving efficiency has been the focus in the Automotive industry.

While optimizing fuel‐efficiency to reduce emissions is a positive development, it is accompanied with negative side‐effects. Car manufacturers opt for lightweight materials such as aluminium and carbon fibre to create lighter, more efficient cars. Processing of these materials however, requires five to six times more energy than steel, the material which they replace. Consequently, energy that

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INNOVATIVE MATERIALS 3 2017

is saved while driving the car is now spent during the production phase.

In addition, recyclability of these lightweight materials is lacking significantly compared to steel.

Bio-plastic

TU/ecomotive utilizes a combination of bio‐based composites and bio‐based plastics to create their chassis. The bio‐based composite is made from flax,

a plant that can be grown in the any moderate climate. The bio‐composite has a strength/weight ratio similar to glass fibre, but is manufactured in a sustainable manner. A honeycomb shaped core produced from bio‐plastic, known as PLA and made entirely from sugar beets, is placed in‐between two flax composite sheets to provide stiffness to the strong composite.

The drivetrain of Lina is electric. Power is supplied by modular battery packs,

giving a power output of 8 kW using two DC‐motors. This allows Lina to reach a top speed of 80 km/h.

To complement Lina’s sustainability, she is equipped with several high‐tech features. NFC technology implemented in her doors is used to detect and recognize different users, which makes Lina highly suited for car‐sharing platforms. http://tuecomotive.nl>

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INNOVATIVE MATERIALS Innovative Materials Innovative Materials provides information on material innovations, or innovative use of materials. The idea is that the ever increasing demands lead to a constant search for better and safer products as well as material and energy savings. Enabling these innovations is crucial, not only to be competitive but also to meet the challenges of enhancing and protecting the environment, like durability, C2C and carbon footprint.

By opting for smart, sustainable and innovative materials constructors, engineers and designers obtain more opportunities to distinguish themselves.

As a platform Innovative Materials wants to help to achieve this by connecting supply and demand. info@innovatievematerialen.nl

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SJP Uitgevers Digital

Innovative Materials is published in a digital format, although there is a printed edition with a small circulation. Digital, because interactive information is attached in the form of articles, papers, videos and links to expand the information available.

There are two editions. The free one is a non-printable magazine, published online. In this version the interactive links are limited.

Subscribers (€ 39,50) will receive full access to both the digital edition and an interactive PDF, with links to all the extra information.

Postbus 861 4200 AW Gorinchem tel. (0183) 66 08 08 e-mail: info@innovatievematerialen.nl Subscription 2017 (6 editions) € 39,50 (ex. VAT)