Special Concrete Typologies IvĂĄn Iglesias GarcĂa KEA 7th Semester Specialization Report Spring 2015
Special Concrete Typologies
Abstract This dissertation is a final specialization report along with my final exam project in 7th semester at Copenhagen School of Design and Technology in order to achieve a degree as a Bachelor of Architectural Technology and Construction Management. This report discusses the special types of one of the most present material in the field of construction and architecture, the concrete. Describing the properties and applications of concrete specially designed to resolve specific needs in a more efficiently way than the traditional concrete. I have selected this topic because I believe that despite having extensive knowledge of the application of concrete, is a little bit outdate, moreover in a short time I will incorporate to the construction sector, therefore I need to have a broad range of knowledge in different special typologies of a material as used such as concrete.
Keywords Concrete, standard concrete, self-compacting concrete, fiber reinforcement concrete, translucent concrete, biological concrete, Special typologies, construction typologies, innovation, sustainable concrete, new concrete.
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Index 1.
INTRODUCTION ...................................... ¡Error! Marcador no definido. - 7
2.
SELF COMPACTING CONCRETE ......................................................... 8 - 12
3.
FIBRE REINFORCED CONCRETE ......................................................... 13 - 17
4.
TRANSLUCENT CONCRETE ................................................................. 18 - 22
5.
BIOLOGIC CONCRETE ....................................................................... 23 - 26
6.
COMPARATIONS ......................................................................................... 27
7.
CONCLUSION .............................................................................................. 28
8.
BIBLIOGRAPHY .................................................................................... 29 - 32
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1. INTRODUCTION 1.1 Background To begin this report I would like to clarify that this is a basic report prepared for the development and progress of the architecture and construction knowledge at a student or a recent graduate level. It is destined to a reader with enough technical knowledge and interested in make it bigger, in this case being one of the most popular materials in our area, the concrete, but from a different point of view not as well known, special concretes. The desire to focus this work to this issue, arose when I realized that after my education in Spain at the Polytechnic University of Madrid in the School of Building and the University of KEA here in Copenhagen, I have acquired a high level of knowledge of everything that encompasses the common concrete, their properties, typologies, composition, applications, etc ... but as I've been going deeper in this sector of the construction and architecture I´ve notice the little knowledge that I have of the varieties of concrete we have at our disposal for many different needs. In as little innovative sector as is the construction compared to other more technological sectors at the industry, it seems very interesting to delve into different types of special concretes that are within our reach in the market today. Nowadays the specialization, in my opinion, is a virtue, both for individuals, professionals, or in this case the materials. I think we should stop using that phrase ¨this material fits all¨. We have enough technology to create materials that fit exactly to each specific need and that is exactly what happens to concrete technology. It is a material that has traditionally been used for everything practical with the same specifications, regardless if we were interested in the resistance, texture, colour, weight ... It was just modified on occasion with regard some sand, the water or add some additive to change the colour, but without seeking the exact adaptation to the needs we had.
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Long since there are many different types of concrete, I've met briefly during my studies and more enthusiastically on television or magazines architecture, calling my attention how in large buildings this type of concrete were used in contrast in construction standards. The fact is that even existing in the market for some time, ignorance of its existence, along with the low productive culture in this sector that was not willing to pay more for something that for them it was still concrete, makes the use of special concrete has not spread like a more regular use. Logically I will not be able to treat all special concretes that exist, but I will develop which have seemed more interesting to me in order to have a wider range for the moment I need to decide for the correct concrete and which one would conformed more to our needs: 1. Self-Compacting Concrete 2. Fibre compacting concrete 3. High resistance concrete 4. Light concrete 5. Biological concrete 6. Translucent 7. Fill concrete Before developing one by one the different special types of concrete I would like to clarify a brief description consisting of conventional concrete.
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1.2 Standard Concrete The concrete is a composite material used in the construction sector, consisting essentially of a binder to which are added particles or fragments of an aggregate, water and additives. The binder is in most cases the cement (usually Portland cement) mixed with a suitable proportion of water for a hydration reaction occurs. The aggregate particles, depending mainly on their average diameter, is aggregate cement mixture alone (classified in gravel, gravel and sand) . Sand and water (without the participation of an aggregate) is called mortar. Cement is a powdery material that by itself is non-agglomerating mixed with water and, upon hydration becomes a mouldable paste with adhesive properties, in a few hours and hardens forge becoming a stony material consistency. The cement consists essentially of hydrated calcium silicate (SCH), this compound is primarily responsible for its adhesive properties. It is called hydraulic cement when the cement hydration resulting is stable under aqueous environment. In addition, to modify some of its characteristics or behaviour, you can add additives and supplements (in amounts less than 1% of the total mass of concrete), and there is a variety of them: dyes, accelerators, retarders, flow, sealants, fibres, etc. Conventional concrete, normally used in floors, buildings and other structures, has a specific density ranging from 2200 to 2400 kg / mÂł. The main structural feature of concrete is very resistant compressive stresses, but has not good resistance to other stresses (tensile, bending, shear, etc.), for this reason it is customary to use certain associated with steel reinforcements receiving in this case the name of reinforced concrete, reinforced concrete or pre-in places; the set behaving very favourably to the various stresses. When a reinforced concrete structure is projected size of the elements are established, the type of concrete and steel additives to be placed depending on the efforts must support and be exposed to environmental conditions. In the late twentieth century, it is the most used material in the construction industry. It is shaped by the use of so-called rigid moulds: formwork. Its use is common in works of architecture and engineering, such as buildings, bridges, dams, harbors, canals, tunnels, etc.
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1.3 Research Method After making a small description of the properties and applications of standard concrete I´m going to focus with more detail one by one in the different special concretes on which this report is based. The methodology I will use for it will be the same for each type of concrete, with the following structure: 1. Properties: making a brief introduction to the material highlighting what makes it different from others concretes and what necessities would resolve. 2. Composition and Dosage: specifying the different components and materials that conform this type of concrete and the amounts of each. 3. Types: In some cases there will be special concretes that have different types depending on their uses or compounds so I will clarify what would be the goal of each one. 4. Execution on site works: Developing the execution process on site with the most appropriate method. 5. Applications: Main uses and needs covering the use of this concrete 6. Examples in Construction: I will take a real case of a building or construction to analyse how it was resolved the necessity that this special concrete fix. After the description of each of the types of special concrete, I will make a comparison in terms of their benefits to know in what situations will be the most appropriate concrete to use.
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2. SELF COMPACTING CONCRETE Self-compacting concrete appears as a response to the difficulties involved in the work of traditional compaction in certain situations. Could be defined as one concrete able to flow through the inside of a formwork naturally, allowing it to pass between the bars of the reinforcement without any segregation or blockage and consolidated without internal or external compaction by the action of its own weight .
2.1 Properties The main differences and advantages of these concretes with respect to traditional lie in: •
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High fluidity due to the use of superplasticizers which allows the concreter each inaccessible places and fill completely sections with a high density of reinforcement. It doesn´t need vibrated and compacted by the action of its own weight, saving corresponding energy and avoiding the high level of noise generated by the vibration. Very easy mold filling even if they are narrow and complex shapes. Improving safety and health in the work to avoiding during the process of pouring the concrete, the use of electrically conductive hoses, generation noise. Improved environmental conditions in the environment works to prevent noise and reduce delays execution. Improving the quality of surface finish views increasing uniformity due to eliminate the heterogeneity that produces vibration.
Pic. 2.01 Civil Center with complex facade, Cordoba, Argentina.
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On the other hand, the main disadvantage this concrete has is the necessity of a much more complex study than the traditional regarding dosing and determining its characteristics.
2.2 Composition and Dosage The components used and the dosing are essential in the proper elaboration of this type of concrete. We can use any of the cement collected by the normative, using an inter filler as needed in order to correct the finer fractions of the sand to ensure that the amount of fines of sizes less than 0.125 is sufficient to achieve the self-compactability. The dosage of cement in a self-compacting concrete is usually between 350 and 500 kg / m3. If the dosage is less than 350 kg / m3, it is necessary to include inert active additions that increase the fines mixture. On the other hand, if the dosage is greater than 500 kg / m3 we must be careful with the retraction of the future concrete. The coarse aggregate usually has a limit of maximum size of 20 mm, being between 12 and 16 mm the size of the more used aggregates. Rolled arid make easy the displacement of the concrete in the mold while the crushing improve its resistance to bending. Coarse aggregate shall have a continuous granulometry and granulometric module less than 2.5 module. Regarding water content is usually around 150 to 200 l / m3 and water / powder ratio between 0.9 and 1.05 resulting a very little concrete cohesive. In this aspect, the additives are totally essential, using superplasticizers in dosages from 1 to 1.5% on weight of cement. Also can be used viscosity modifiers, but only on certain occasions. The manufacture of these concretes is usually done in Central where the appropriate adjustments in the amount of mixing water are performed and the granulometry of the aggregated is systematically controlled. The mixing time of self-compacting concrete should be longer than the traditional ones to make the additive get full effect on the dough.
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2.3 Types •
Basic Self-Compacting Concrete
As its name indicates it´s the standard type of self-compacting concrete, is used when the necessities of a self-compacting concrete are the basic ones. It has an easy execution on site allowing concreting in slightly inclined planes with a simple pumping. We will use in case of slightly reinforcement concrete structures like slabs, walls and columns. The cost of this typology due to its basic characteristics it is also cheaper than the Superfluid or the Architectonic. •
Superfluid Self-Compacting concrete
Because of its great fluidity is distributed uniformly by the formwork with minimal compaction effort. This type of Self-Compating concrete extends life of formworks and has a safer execution on site. The Vibration phase is reduced so also is reduced the labour force. We will used in case of high reinforcement concrete structures with complex form and difficult access. •
Architectonic Self-Compacting concrete
This concrete is distributed and self-expanding reaching every corner of the formwork without using any external compacting method. Saving in labour and vibration tools, flowing easily in remote areas of the discharge point, with a super easy pumping. We use it in case of high aesthetic requirements and very complex forms with high reinforcement structures in works of extremely shorts periods of execution.
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2.4 Execution on site works Execution on site involves substantial advantages over traditional concrete, being able to be pouring pumping or by injection. The most used method is pumping but being careful with the tightness and stiffness of the molds. The concrete is able to move within reach higher than 15 meters distance. One advantage of this type of concrete is that we don’t need to pour the concrete in different tiers or batches, since it´s not necessary to keep together the different tiers neither vibrate it, so the pouring may be continuous as the concrete will be distributed and uniformly compacted itself without vibrated. It can also be concreted from the bottom of the formwork, through special molds which allow the connection of a placing pump by which enters the concrete to the element, rising from below and avoiding the disintegration of the concrete in elements with high elevations. In this way we get a continuous concreting, without stops or PIC. 2.02 Worker concreting on the formwork concrete joints, with the guarantee of complete filling of the formwork, without gaps or voids and, of course, any disintegration of the concrete. It is essential to use formwork and well-sealed airtight, ensuring that the formwork doesn’t present imperfections and distortions because the selfcompacting concrete would exactly replicates these forms. We would pay attention that the appropriate release agent is used, as for example release agents. Once in place, it´s recommended to have the curing of the concrete as soon as possible to avoid shrinkage cracks
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2.5 Applications One of the main uses is the manufacture of concrete parts with very complicated shapes. The result are pieces with very nice and flawless surfaces. They are also used in the construction of major infrastructure, such as bridges or tunnels, where the work of compaction is complicated.
PIC. 2.03 Complax shapes panels
2.6 Examples in Construction This product was chosen to build the spectacular building car company BMW in Germany, designed by architect Zaha Hadid. The building of great constructive complexity was conceived entirely in exposed concrete which was decisive to the develop a self-compacting high performance concrete able to solve formal and structural seemingly irreconcilable demands and aesthetic requirements of high quality and sophistication. Also due to the extraordinary dimensions of the project was important to achieve high productivity in the execution on site and high resource efficiency.
PIC 2.04 Exterior façade, BMW, Germany
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PIC 2.05 Interior area, BMW, Germany
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3. FIBER REINFORCEMENT CONCRETE It is known that concrete is a perfect material to resist compression forces but it ceases to be when he has to resist the tension. However this particular typology of fiber reinforced concrete has a revolutionary change to the traditional conception of concrete.
PIC 3.01 Fiber reinforced beam
The fiber reinforced concrete is a concrete made with cement containing coarse and fine aggregates and discontinuous fibers. The fibers can be natural or artificial which aim is to strengthen the cement mass increasing the tensile strength and the crack growth is retarded and increases the hardness transmitting the effort through the cracked section. The fiber reinforcement improves the impact resistance and fatigue resistance and curing shrinkage decreases.
3.1 Properties • •
•
The real contribution of the fibres is to increase the toughness of the concrete under any type of loading. The fibre reinforcement may be used in the form of three – dimensionally randomly distributed fibres throughout the structural member when the added advantages of the fibre to shear resistance and crack control can be further utilised. The role of the fiber reinforcement in concrete is not to increase strength, although modest strength increases may occur. Rather, the role of discrete, discontinuous, randomly oriented fibers is to bridge the cracks that develop in concrete either due to environmental changes (such as drying) or as it is loaded. If the fibers are strong enough, stiff enough, and present in sufficient quantity and develop sufficient bonds with the cementitious matrix, they will serve to keep the crack widths small and will permit the fiber reinforcement concrete to withstand significant stresses over a relatively large strain capacity in the post-cracking (or strain-softening) stage.
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3.2 Composition and Dosage The amount of fibers added to a concrete mix is measured as a percentage of the total volume of the composite (concrete and fibers) termed volume fraction (Vf). Vf typically ranges from 0.1 to 3%. Fibers with a non-circular cross section use an equivalent diameter for the calculation of aspect ratio. If the modulus of elasticity of the fiber is higher than the matrix (concrete or mortar binder), they help to carry the load by increasing the tensile strength of the material. Increase in the aspect ratio of the fiber usually segments the flexural strength and toughness of the matrix. However, fibers which are too long tend to "ball" in the mix and create workability problems. Fibres aligned in the direction of the tensile stress may bring about very large increases in direct tensile strength, as high as 1.33% for 5% of smooth, straight steel fibres.
3.3 Types •
Polymeric fibers reinforced concrete
In this case the fibers are polymer (plastic) and this fibers are also resistant to alkali. The problem they have is that their mechanical properties are low (with small elasticity modules and reduced adhesion) PIC 3.02 Polymeric Fiber
The lengths of the fibers are between 10 to 60 mm. These are added in the mixer in amounts of 1 to 3% by volume. Are mostly used as reinforcement of mortar, controlling shrinkage cracking, for prefabricated elements (improve the impact resistance and the splitting of the finished pieces) and concretes projected achieving greater thicknesses material without sagging. With these fibers will increase the impermeability and durability of concrete and notice a reduction in costs compared to other typologies.
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Glass fiber reinforced concrete
The length of this type of fibers is up to 40 mm and the usual contents are about 5% in the totality of the dosage. The fiberglass must be resistant to attack by alkali cement. Especially are used in sprayed concrete, since it is a kind of flexible material allowed to mingle with the concrete without disintegrating.
PIC 3.03 Glass Fiber
They are widely used in façade panels mostly with architectural or coating purposes. It is also used for resistant fire and noise walls and partition .
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Steel fiber reinforced concrete As In this case the fibers have diameters from 0.3 to 1 mm and its length 25 to 75 mm. They usually have different shapes and wavy being the most common hooked. The steels used are carbon steels or stainless. PIC 3.04 Steel Fibers
The mixing of the fibers occurs at the end of the kneading process. These concretes have less docility than traditional concrete. we should anticipate a uniform dispersion of the fibers and prevent a segregation or entanglement of the fibers. The steel fiber concrete is also used as spray concrete. The fiber content is generally between 1 to 3% in volume and increasing it the mechanical properties are increased but the workability is impaired. Flexural strength is increased 3 times that of a non-reinforced concrete. The impact resistance increases 4 to 6 times normal concrete. Are very expensive, 1% fiber aggregate of this type involves doubling the cost of concrete approximately. They are used for industrial flooring, airport runways, precast, tunnels avoiding placing the electro welded mesh.
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3.4 Execution on site works Although the fiber prevents cracking, we have to watch over the curing conditions avoiding drying of the top layer of concrete Do not make any alteration of the mixture on site (such as adding water, fiber). Fiber already has the perfect dosage of all elements due to it comes mixed from the factory. It doesn´t need special care with the pouring of the concrete to prevent the formation of tangles. The distribution of the fiber in the concrete is homogeneous because it is premixed in the factory.
3.5 Applications One of the most important applications is the execution of concrete slabs and screeds, making easy the execution thereof by eliminating the retraction reinforcement and even making bigger the distance between expansion joints. Also for prefabricated elements whose dimensions and thicknesses are optimized. Transportation, placement of these elements make susceptible to cracking and chipping that is why the fibers in these cases are very useful because cracking of the elements is reduced and if it happen, they allow the unit to continue operating without discard it. Also in rehabilitation can be used to make fiber concrete screeds slabs or tiles. They can be particularly suitable the plastic fibers for the execution of more exposed elements, eliminating much of the reinforcement steel avoiding corrosion problems of the armor, so we eliminate one of the biggest problems of concrete that are for example in contact with the ground. Especially in tunnel applications the polypropylene fibers have an additional advantage, the fire resistance. The fire in a tunnel is one of the most complex risk situations due to the difficult renewal of air, so this type of fibers becomes the best choice.
Iván Iglesias García
PIC 3.05 Tunnel site
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3.6 Examples in Construction The Oceanographic is a complex located in the city of Valencia (Spain) designed by architect Felix Candela where different marine habitats are represented. With an extravagant shape reminiscent of the waves, its structure had a difficulty to withstand the loads both bending and torsion, it is for this reason that it was decided to reinforce the concrete with steel fibers. A thin sheet of concrete, was executed by dry spraying. The percentage of rejection in the spraying process was about 15% in the lower areas of the cover and it was reduced to zero through the areas on the top due to the reinforcing fibers. Also thanks to this type of reinforcement in the concrete was possible to achieved that the time of concreting of the sheet was half the time of construction than with a standard concrete without steel fibers.
PIC 3.06 Oceanographic museum, Valencia, Spain.
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4. TRANSLUCENT CONCRETE The purpose of this special type of concrete arises from the monotony of dull and grey traditional concrete; therefore his days are coming to an end. The translucent concrete it´s exactly this, a kind of material that allows light to partially pass through it without being considerably affected its mechanical and structural properties, displaying a view of the outside world, such as the silhouette of a tree for example.
PIC 4.01 Shadows through the façade wall
4.1 Properties The main advantage of transparent concrete is that it can transmit light. •
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It can be used to make green buildings. Since it can transmit more than a 70% of light from natural as well as artificial sources, the building can have fewer lights to meet its demand for lighting. Thus saving huge energy cost. Transparent concrete uses sunlight as source of light instead of electrical energy and reduces power consumption. This concrete can also be used cold countries to transmit heat with sunlight. We wouldn’t need any coated because the porpoise is to get the light pass through, causing savings in finishing materials as plaster and paint, achieving with this way a reduction in emissions of greenhouse gases. Due to the incorporation of the optical fiber in its composition we also improved its waterproof property making it up to 25% more efficient in this respect than traditional concrete. It is around 20% lighter than a traditional concrete. On the other hand we must take into account that the cost of translucent concrete is twice or half twice the price of the traditional concrete, but its price is justified by the benefits it provides.
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4.2 Composition and Dosage Transparent concrete is manufactured by using combination of fine concrete and fiber optics. These fibers blend into the concrete like any other aggregates. These optical fibers can transmit light from natural and artificial sources into spaces enclosed by the translucent concrete panels. The principal reason for using optical fiber in concrete is that it can transmit light even an incident angle greater than 600. • •
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Cement: The binder used here is a white cement with a whiteness index higher than 85% realized by inserting titanium dioxide. Sand: Since the transparent concrete is manufactured only using fine materials, the size of sand should pass through 1.18mm sieve. The sand should be free from any impurities such as vegetation, large stones etc. Water: Water to be used for transparent concrete should be of drinking water quality, free from any impurities. Optical fibers: Optical fiber consists of three layers called as core, cladding and buffer coating or jacket. The light is transmitted through the core of the optical fiber. The proportion of the fibers is very small (4%) compared to the total volume of the blocks. Thickness of the optical fibers can be varied between 2 µm and 2 mm to suit the particular requirements of light transmission.Moreover, these fibres mingle in the concrete because of their insignificant size, and they become a structural component as a kind of modest aggregate.
PIC 4.02 Cross section of optical fiber
Since the finish of this concrete depends on the components and additives with which it is made, it can achieve higher transparency
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4.3 Types •
Translucent optic fiber concrete
Incorporating thousands of fiber optic strands with a diameter between 2 microns and 2 mm, all oriented in the same direction from one face to the opposite of a plate concrete. In the direction of the fibers transmits light and translucent plate is perceived as concrete, while in the transverse direction to the fibers is not transmitted light and is perceived as opaque. The smaller the thickness of the concrete slab (and the greater the intensity of the light behind the panel) translucency greater effect is obtained. In the pictures you can see as clearly perceive silhouettes. PIC 4.03 Optic fiber concrete blocks
It is produced in pieces with a maximum size of 30 x 60 inches. With a strength of 250 to 900 kg/cm² and a volumetric weight of 2100-2400 kg/m³ . These pieces reach their final strength at 28 days and then will be transported to the site. •
Polymeric Translucent Concrete
Replacing all (or most) of the normal binder of the concrete (cement) of a material that also has (therefore adhesive) binders properties while translucent properties, such as polymers. This ensures that the mass is translucent glass in all directions, with a light transmission of up to 80%. Consist on a translucent paste that is PIC 4.04 Polymeric Translucent concrete Wall attachable in the necessary formwork on site acquiring its strength at 7 days. With a resistance of 2500 to 4500 kg/cm² and a volumetric weight of 1900-2100 kg/m³.
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4.4 Execution on site works There are only a select few companies, and the process is somewhat low-tech and slow. It can only be produced as precast or prefabricated blocks and panels; it cannot be poured on site like traditional concrete. The blocks can be produced in various sizes with embedded heat isolation too. IPIC 4.05 Prefabricated blocks
The surface of blocks remains homogeneous concrete, therefore union of the blocks and tiles is made by a common bond, with transparent features to keep the conditions of translucency. It can be also arrange together with the support of a frame or structural framing. Vertical joints are made on expansion, in this way the panels act independently to other construction elements. Joints also will have waterproof seal with a compatible nature with the other elements.
4.5 Applications Regarding the strength to resist high loads this material is still not sufficiently prepared, but is true that its development could lead to start using it as such. However it can be used as coating systems for vertical façades allowing the light pass through it, saving electricity light and heating energy. That is why is starting to be used to illuminate the interior of offices and shops. In Addition also is applying this versatile material for the production of both exterior and interior furnishings illuminated from the interior creating a more modernist effect.
PIC 4.06 Interior Illuminated Furniture
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4.6 Examples in Construction This original project is the Italian Pavilion at the Shanghai World Expo 2010 designed by IodiceArchitetti and is the first major application of translucent concrete in a building. The translucent blocks of concrete were interspersed with opaque blocks to create a seamless façade that allows diffused light in at certain areas, PIC 4.07 Exterior façade of the Italian Pavilion and emanates a glow at night, giving an effect of lightness against the tough external effect. 3,774 transparent panels were used to cover a total area of 1,887 square meters, amounting to about 40% of the entire facade of the pavilion. To date, it is the only building that has used this material, but is an example of progress constructions will be incorporated in the future soon.
Iván Iglesias García
PIC 4.08 Interior view of the Transparent facade
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5. BIOLOGICAL CONCRETE This type of concrete is an example that shows how the future of design requires thinking innovatively about the way construction techniques function so we may expand upon their capabilities. Sustainability has evolved far beyond being a trend and has become an indelible part of this design process. Sustainable solutions have always pushed against the status quo of design, and now the biological concrete has been developed sustaining and encouraging the growth of a multitude of biological organisms on its surface.
PIC 5.01 Green facade
5.1 Properties The main characteristic of biological concrete is that supports the growth of organisms on its own surface.
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The innovative feature of this special concrete is that it acts as a natural biological support for the growth and development of certain biological organisms, to be specific, certain families of microalgae, fungi, lichens and mosses. From an environmental perspective, the new concrete absorbs and therefore reduces atmospheric CO2, thanks to its biological coating. It has the capacity to capture solar radiation, making it possible to regulate thermal conductivity inside the buildings depending on the temperature reached. The biological concrete also acts as an ornamental alternative.
5.2 Composition and Dosage The composition of this typologies of special concrete has been based in two cement-based materials. The first of these is conventional carbonated concrete (based on Portland cement), with which they can obtain a material with a pH of around 8. The second material is manufactured with a magnesium
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phosphate cement (MPC), a hydraulic conglomerate that does not require any treatment to reduce its pH, since it is slightly acidic. On account of its quick setting properties, magnesium phosphate cement has been used in the past as a repair material. It has also been employed as a bio cement in the field of medicine and dentistry, indicating that it does not have an additional environmental impact. In order to obtain the biological concrete, besides the pH, other parameters that influence the bio receptivity of the material have been modified, such as porosity and surface roughness. The result obtained is a multilayer element in the form of a panel which, in addition to a structural layer, consists of three other layers: the first of these is a waterproofing layer situated on top of the structural layer, protecting the latter from possible damage caused by water seeping through. The next layer is the biological layer, which supports colonisation and allows water to accumulate inside it. It acts as an internal microstructure, aiding retention and expelling moisture; since it has the capacity to capture and store rainwater, this layer facilitates the development of biological organisms. The final layer is a discontinuous coating layer with a reverse waterproofing function. This layer permits the entry of rainwater and prevents it from escaping; in this way, the outflow of water is redirected to where it is aimed to obtain biological growth.
5.3 Types Because of the novelty and complexity of this type of concrete still research continues on the standard and basic biological concrete way therefore it has not been created different typologies within this. In the future we could see different kinds of biological concrete able to withstand small medium and large species of vegetation, or able to resist soft medium and extreme weather. But for the moment the biological concrete continues developing and researching in the standard line.
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5.4 Execution on site works In contrast to the biological concrete, the vegetated façades and vertical gardens depend on a plant substrate in some type of container, or they use cultures that are totally substrate-independent, such as hydroponic cultures. However, they require complex systems attached to the construction itself (layers of material) and even adjacent structures made of metal or plastic. This can lead to complications associated with additional loads, the reduction of light, or the reduction of space PIC 5.02 Biological Panels Facade around the building. With the new “green” concrete, the organisms can grow directly on the multi-layered material because complex supporting structures are not required, and it is possible to choose the area of the façade to which the biological growth is to be applied. Therefore the execution in work of this kind of special concrete will be manufactured as prefabricated panels and supplied in different sizes at the site. Placed modularly as facade cladding.
5.5 Applications The material, which has been designed for the façades of buildings or other constructions in Mediterranean climates The biological concrete has been designed for the colonisation of certain areas with a variety of colours, without the need to cover an entire surface. The idea is to create a patina in the form of a biological covering or a “living” painting. This type of concrete would be a nice alternative for façades and buildings or other constructions in the Mediterranean climates due to the conservation of its vegetables characteristics, Currently being investigated the best way to promote the accelerated growth of these types of organisms on the concrete. The goal of the research is to succeed in accelerating the natural colonisation process
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so that the surface acquires an attractive appearance in less than a year. A further aim is that the appearance of the façades constructed with the new material should evolve over time, showing changes of colour according to the time of year and the predominant families of organisms. On these kinds of buildings, other types of vegetation are prevented from appearing, lest their roots damage construction elements. There are also possibilities for its use in garden areas as a decorative element and as a sustainable means of blending buildings and constructions into the landscape. The material lends itself to a new concept of vertical garden, not only for newly built constructions, but also for the renovation of existing buildings. Giving to the new ones a green and sustainable aspect.
5.6 Examples in Construction The Aeronautical Cultural Center in El Prat de Llobregat designed by Sergi Godia, Berta Barrio and Eloi Juvillà in 2009 is a Hangar to house, display and repair aircraft of the Second World War and the Spanish Civil War. The project explores the types, building systems and materiality of the hangars and old airplanes mixing past and present, old and new. The exterior skin is continuous made of concrete panels, alternating precast concrete standard, and biological concrete panels, giving the facade both, grey concrete of the past in the Spanish civil war, and green concrete of a sustainable present. With this biological concrete facade acts as a vertical garden maintenance, changing throughout the seasons.
PIC 5.03 Aeronautical cultural centre, Cataluña, Spain.
Iván Iglesias García
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6. COMPARATIONS The table below shows in a schematic and brief form a comparison of the most important aspects of each different special typology of concrete I have discussed throughout this report.
SELF-COMPAC.
FIBER
TRANSPARENT.
FEATURE
High fluidity.
High resistance to tensile forces & hardness in cracked sections.
Allows light to partially pass through it.
ADDITIVE
Superplasticizers.
Polymeric fibers, glass fibers, steel fibers.
Optical Fiber
Magnesium phosphate cement.
EXECUTION SITE
Pumping and injection in high density of reinforcement.
The correct dosage comes from the factory.
Precast or prefabricated blocks and panels.
Prefabricated panels placed modular.
STRUCTURAL
Complemented with reinforcement and other bearing elements.
Appropriate to withstand all types of structural loads.
Not sufficiently prepared to resist high loads.
Not sufficiently prepared to resist high loads
EXTERIOR COATING
High quality of heterogeneity exterior surface with complex forms.
Doesn’t have an aesthetic finish so it needs a finish coating
Vertical coating for illuminated facades.
Modular panels making a green façade that changes colour along the time.
APPLICATION
Panels with complicated shape.
Slabs and screeds eliminating the reinforcement. Prefabricated elements.
Illuminate the interior of buildings and production of illuminated furnishings.
Vertical gardens in new and renovating buildings.
ECOFRIENDLY
Save vibrated and compacting energy. Avoiding noise.
The polymeric fibers replace the steel making it more sustainable.
Totally sustainable saving electricity light and heating energy.
Ecological Material reducing CO2 & regulating thermal conductivity.
Iván Iglesias García
BIOLOGICAL
Supports the growth of organisms on its own surface.
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7. CONCLUSION We must prepare to deal with the technological advances that the future is presenting us, taking into account aspects such as efficiency and sustainability. The standard concrete is a material which in itself already has fabulous construction features but we should choose the most appropriate special version to cover the most indicated necessities without fear to get into something not so known and investigate or investing more budgets because it is demonstrated that over time the election will be more sustainable and profitable. In this report I have analysed four types of special concretes, two of them, self-compacting concrete and fiber reinforced concrete are already known worldwide and its use is expanding over the world as a common alternative, this special concrete are two cases that should be an example for the other two special concrete that I have analysed, the transparent and biological. We must rely more on new types and invest more in this type of project, because only on this way we will improve our architecture and little by little getting that necessary sustainability aspect. I hope that this study will make both me and the readers to have a greater range of choices to make wiser choices of concrete, always thinking on the more sustainable and efficient aspects without getting stuck in obsolete.
Thank you for your time reading this report, Iván Iglesias García
Iván Iglesias García
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8. BIBLIOGRAPHY 1. Standard Concrete WEBS / FOROS / INTERNET •
http://www.concreteconstruction.net/table-ofcontents/magazine.aspx
•
http://www.concretecentre.com/technical_information/buildi ng_solutions/modern_methods_of_construction.aspx
BOOKS •
Technical Building Code - CTE Spain - 2013
2. Self-Compacting Concretes WEBS / FOROS / INTERNET •
http://masqueingenieria.com/2015/01/29/hormigonesespeciales-hormigon-autocompactante/
•
http://www.hormigonespecial.com/familia/hormicompac3.html
ARTICLES •
¨Self-compacting concretes for the new cities¨ James Connely – 29 February 2011.
•
¨Typologies of concrete¨ - Enrrique Lario - 25 Agoust 2010.
BOOKS •
¨EUROCODE 2: Design concrete structure – Part 1: General Rules¨ 2010.
•
¨European
Guidelines
Specifications
for
production
self-compacting and
use¨
concrete: BIMBM,
CEMBUREAU,ERCO,EFCA - Year 2010. •
¨Structural application of self-compacting concrete¨ RILEM publications PRO 33 – Walraven, J - Agoust 2011.
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Special Concrete Typologies
PICTURES •
Picture 2.01: http://www.vaingenieria.com.ar/civico1.html
•
Picture 2.02: Article ¨Typologies of concrete¨ - Enrrique Lario 25 Agoust 2010.
•
Picture 2.03: Article ¨Typologies of concrete¨ - Enrrique Lario 25 Agoust 2010.
•
Picture 2.04: www.openbuildings.com
•
Picture 2.05: www.openbuildings.com
3. Fiber Reinforcement Concrete WEBS / FOROS / INTERNET •
http://www.monografias.com/trabajos12/hores/hores.shtml
•
http://theconstructor.org/concrete/fibre-reinforced-concretein-pavements/4781/
•
http://theconstructor.org/concrete/applications-of-steel-fiberreinforced-concrete/6117/
•
http://www.hormigonespecial.com/hormiFibra_PP.php
•
http://oceanografic.wordpress.com/
ARTICLES •
¨Typologies of concrete¨ - Enrrique Lario - 25 Agoust 2010.
•
¨ Superintending Engineer¨- Dr. K.M.Soni – 10 March 2012.
•
¨Construction of the JCHYPAR, a steel fiber reinforced concrete membrane at the oceanographic park in Valencia¨ - Alberto Domingo – 15 March 2003
PICTURES •
Picture 3.01: www.sika.com
•
Picture 3.02: www.fibretech.com
•
Picture 3.03: www.brigthubengineering.com
•
Picture 3.04: www.brigthubengineering.com
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Special Concrete Typologies •
Picture 3.05: www.tunneltalk.com
•
Picture 3.06: Article ¨Construction of the JCHYPAR, a steel fiber reinforced concrete membrane at the oceanographic park in Valencia¨ - Alberto Domingo – 15 March 2003
4. Translucent Concrete WEBS / FOROS / INTERNET •
http://jm3studio.com/el-hormigontranslucidoexhibicionismo -constructivo
•
http://theconstructor.org/concrete/transparentconcretelight-transmitting-concrete/9271/
•
http://constructionduniya.blogspot.dk/2012/02/newmaterils -in-construction-concrete.html
ARTICLES •
¨Construction exits¨ Cristina Lopez - 7 June 2014
PICTURES •
Picture 4.01: www.kliton.com
•
Picture 4.02: www.equestionsanswers.com
•
Picture 4.03: www.revitcity.com
•
Picture 4.04: Article ¨Construction exits¨ Cristina Lopez 7 June 2014
•
Picture 4.05: www.litracon.com
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Picture 4.06: www.techzug.com
•
Picture 4.07: www.landscape.com
•
Picture 4.08: www.landscape.com
Iván Iglesias García
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Special Concrete Typologies
5. Biological Concrete WEBS / FOROS / INTERNET •
http://www.dezeen.com/2013/01/03/spanish-researchersdevelop-biological-concrete-for-moss-covered-walls/
•
http://www.archdaily.com/315453/biological-concrete-fora-living-breathing-facade/
ARTICLES •
¨Research at the UPC New biological concrete for construction¨ Universidad Polytechnic de Cataluña – 12 December 2012
PICTURES •
Picture 5.01: http://www.upc.edu/
•
Picture 5.02: www.blogdeldiseño.com
•
Picture 5.03: www.construccion21.com
Iván Iglesias García
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