CLC - LIGHTWEIGHT CELLULAR CONCRETE”MONOLITHE Method””

The CLC - Lightweight Cellular Concrete “MONOLITHE Method” is the result of the synergiesbetween Techno Consulting and a Group of Italian Firms, high specialized in the Building Industry and inthe development of hi-tech innovative dedicated technologies and solutions.

The CLC - Lightweight Cellular Concrete “MONOLITHE Method” is an innovative building method, but it canalso be described as “Building Operational Modality” or “Building Process”, developed by the high skill andconsequential well-advised activities of Techno Consulting, starting from the consolidated basic technologieson the CLC, which material is known and used Worldwide in the Building Industry for decades by now.

The CLC is a concrete, which includes an “Inorganic Expanding Agent” that increases the volume of themixture, while reducing its dead weight. CLC is lighter than the conventional concrete with a dry density from200 kg/m3 up to 1840 kg/m3.

PROPERTIES: CLC concrete is a versatile building material produced in a variety of densities, depending onthe application.

RECENT DEVELOPMENT: In the last decades, CLC has been used extensively in:• highways;• commercial buildings;• disaster rehabilitation buildings;• schools;• apartments; and • housing developments

in Countries, such as: Germany, USA, Brazil, Singapore, India, Malaysia, Kuwait, Nigeria, Botswana, Mexico,Indonesia, Libya, Saudi Arabia, Algeria, Iraq and Egypt, to mention a few.

ADVANTAGES: CLC is of utmost importance to the construction industry. To mention a few, the advantagesof it:

• Reduction of mass and improved thermal, antiseismic, fire proof and sound insulation properties,while maintaining adequate strengtht.

• Structure design, leading to savings in supporting structures and foundation.• Weight reduction of superstructure using CLC concrete walls: less steel reinforcements required for

slabs, columns, beams and foundation due to lesser load. • Earth quake resistant due to lesser weight of building in multistory buildings • Suitable for buildings in hurricane, cyclone and flood affected areas. • Reduced cost of raw materials.• Environmentally-friendly/Energy savings.• Total recyclability of the finished product. There are no production waste, because residues and

scraps (for example: cuts during production or waste in the installation) can be ground and re-used inthe dough even in high percentages, subject to the quality of the sand and the final density to beachieved.

• Cost reduction for transportation and storage: Less raw materials, very efficient foam concentrate. • Faster construction using cast-in-situ application • Improved thermal insulation: CLC can achieve the same insulation results as normal concrete with

only 20% of the weight and 10% of raw materials. • Improved fire protection: A wall of 13cm thickness and 1,250kg/m³ can withstand a fire for 5 hours. A

wall of 10cm thickness and only 400kg/m³ achieves the same result, due to the air enclosed in thecellular concrete.

• Easy to use/producing/handling • Low investment.• High flowing capability: It can fill hollow spaces. • Low water absorption.

USES: The primary use of CLC is to reduce the dead load of a concrete structure, which then allows thestructural designer to reduce the size of columns, footing and other load bearing elements.CLC enhances the fire protection and can be used as insulating blocks.

Structural CLC has been used for bridge decks, piers and beams, slabs and wall elements in concrete andsteel buildings, parking structures, tilt-up walls, topping slabs and composite slabs on metal decking.CLC is fire resistant and its thermal and acoustical insulation properties make it ideal for a wide range ofpurposes, from insulating floors and roofs, to void filling. It is also particularly useful for trench reinstatement.

APPLICATION: Few of the applications of CLC concrete are:• precast blocks / boards / panels;• precast wall elements / panels; • cast-in-situ / cast-in-place structures and walls; • insulating compensation laying; • insulation floor screeds; • insulation roof screeds; • sunken portion filling;• trench reinstatement; • sub-base in highways;• filling of hollow blocks; • prefabricated insulation boards.

CHARACTERISTICS:

• Excellent Acoustic Performance: It can be used as effective sound barrier and for acousticsolutions. Hence, highly suitable for partition walls, floor screens / roofing and panel material inauditoriums.

• Earthquake Resistant: Since lighter than concrete and brick, the lightness of the material increasesresistance against earthquake.

• Insulation: Superior thermal insulation properties compared to that of conventional brick andconcrete, so reduces the heating and cooling expenses. In buildings, light-weight concrete producesa higher fire rated structure.

• Workability: Products made from CLC are lightweight, making them easy to place. It is simpler thanbrick or concrete.

• Lifespan: Weather proof, termite resistant and fire proof.

• Savings in Material: Reduces dead weight of filler walls in framed structures by more than 50% ascompared to brickwork resulting in substantial savings.

• Water Absorption: Closed cellular structures have lower water absorption.

• Skim Coating: Do not require plaster and water repellent paint suffices. Wallpapers and plasterscan also be applied directly to the surface.

• Modulus of Elasticity: The modulus of elasticity of the concrete with lightweight aggregates islower, 0.5 - 0.75 to that of the normal concrete. Therefore more deflection is there in lightweightconcrete.

• Shock-absorption: CLC has been investigated also for use as a bullet trap in high intensity militaryfirearm training ranges. The energy absorption capacity of CLC was approximated from drop testingand found to vary from 4 to 15 MJ/m3 depending on its density. With optimum absorption estimatedfrom a 1000kg/m3 moderate density mix at water to cement (w/c) ratios from 0·6 to 0·7.

MANUFACTURING: CLC concrete typically consists of a slurry of cement and water with the foaming agentmixed in a mixing plant. The foaming agent used will be able to produce air bubbles with a high level ofstability, resistant to the physical and chemical processes of mixing, placing and hardening.CLC concrete mixture is pumped into moulds, or directly into structural elements. The foam enables theslurry to flow freely due to the thixotropic behaviour of the foam bubbles, allowing it to be easily poured intothe chosen form or mould. The material requires up to 24 hours to solidify.

The “MONOLITHE Building Method” engineered and developed by Techno Consulting, is innovative,essentially for the following main aspects:

• Use of a bearing structure made of hot galvanized steel, which, on the base of specific structuralcalculations that the Group's specialized Engineers, Architects and Experts develop on the projectsupplied by the customer, allows the construction of one-or-multi-storey buildings, hospitals, artisanalor industrial settlements, hotels, shopping malls, etc. It only is a question of evaluation of costs,compared to other kinds of bearing structures and of the cohesion of the performances between theframe and the cladding in CLC and the finish materials which, in this case, are called “panels”,contributing to the rigidity and to the structural stability of the building. The structural steel cage is

completely connected, included floors and roof. The CLC casting does not have interrruptions orjoints and therefore, the whole structure results being a “single body” with a “box behavior”, withoutdiscontinuity points, or connections, or fastening.

• Use of “lost formworks”: meaning containment of the casting slabs on CLC that, at the end of thework, become integral and functional part of the structure, besides internal and external plasters. Theformwork do not have bearing purpose but it only is a support and is screwed to the steel frame toensure the necessary continuity. For the finish of the external walls, it is provided the levelling withnet + mortar quartz and acrylic- siloxane paints. For the internal walls, it is provided an insulatinglayer and plasterboard (some pictures here-by attached);

• Use of specific pumps and mixing units designed and produced on Techno Consulting's specification,allowing the correct mixing and the pumping of the CLC concrete mixed with an Inorganic foamingagent;

• Use of a specific and performing Inorganic foaming agent, which lightenings the specific weight ofthe concrete according to the use of it and, while drying (it normally takes 24 hours), makes the CLCstable and homogeneous.

As to the galvanized steel frames needed for structure, partitions and roof, they will be evaluated on thebase of the project of the building to be realized for the drawing and the processing specification of the bars,starting from the materials available locally.

Finally, the Group is available to technically train Builders/Entrepreneurs, allowing them to become licencedfor the use of the “MONOLITHE Building Method” and of the related technologies, as well as trainingworkers.

For South Africa and SADC Countries, TECHNO CONSULTING is represented on exclusive byFINMASTERS SA.

Building with LIGHTWEIGTH CELLULAR CONCRETE -CLC-

The CLC is a new material in the world of construction, although the study and the first production of it datesback to about a century ago. It was found out in 1924 by Swedish Architect J.A. Eriksson, in search of amaterial that had the same characteristics as the timber (insulating, sturdy, easy to work), without itsdisadvantages (the combustibility and the low water resistance). It is now used to build walls of any kind, notonly partitions, but also bearing walls. Thanks to its large capacity of thermal insulation, it can replace thecomposite walls, where it is necessary to provide ventilated walls and insulating materials, besides claybricks, or other common building materials.Based on the quality achieved after years of studies and tests during the production phase (prefabrication orcasting on site), the Group is able to offer a new CLC type: qualitatively enriched with specific characteristicsthat makes it suitable and effective to meet the performance requirements imposed by the new housingstandards, besides being innovative in the production system.

Fundamental logistical, technical and economic parameters- Stability of the product during the production phase; - Performance constancy; - Eco-friendly - 100% recyclable, ideal for seismic zones, needs less power, provides more comfort,

thermal inertia, sound insulation, fire resistance; - Use of raw materials available everywhere in the World (cement and sand) and not subject to special

treatment or adjustments to be compatible with the technology (example: spraying sand with ball mill incase of Aerated Autoclaved Concrete AAC);

- Reduced investments and start-up costs; - Speed of siting; - Immediate possibility of changing density (kg/m³) of the product during the production and/or casting on

site, according to the possible different uses within the same building (load-bearing walls, partitions, floorscreeds, screeds lightweighted until the density of 300 kg/m³).

TECHNICAL FEATURESChemical compositionThe main components of the CLC concrete are: cement, water and a “foam additive”, which is present inevery typology of buildings to be realized. Corrosive substances, such as chlorides, are not contained in it.The usual concretes are generally made of a mixture of cement (about 11 to 18%) water (7÷9%) sand andaggregate (74÷80%).The CLC is different as the aggregate is partially or completely replaced by small air bubbles that arepumped in the dough. The amount of these small cells will determine the characteristics of the material to beachieved: lightweight, insulation, mechanical strength, fireproof, workability, etc. In that way, the concrete gains flexibility, thanks to the homogeneous distribution of the light cells, in theeasiness of the preparation and dosage techniques and in the reliability of the material and its features.

Therefore, the definition of CLC is: a concrete consisting in cement, water, aggregate (if present) and air inthe form of small preformed bubbles, with a density from 300, to 1800 kg/m³.Cellular concretes with a density between 300 and 400 kg/m³ are used as insulation for heat, sound andvibration; underground pipes; fire barrier walls; filler of underground cavities; land settlements; anti-vibrationslabs and similar uses. Cellular concretes with a density from 400 to 500 kg/m³ are used for the construction of light castings for thecoating of ceilings, floors and roofs. Masonry blocks and precast panels require at least a density of 550 to800 kg/m³.

WATER

CEMENT

AGGREGATES

SAND

WATER

CEMENT

AIR

SAND

WATER

CEMENT

ORDINARY CONCRETE CELLULAR CONCRETEdensity 500÷1.800 kg/m³ density 300÷400 kg/m³

AIR

CELLULAR CONCRETE

Cellular concretes with a density from 800 to 1800 kg/m³ can be considered as lightweight structuralconcretes.

Dimensional stability and thermal expansion Industrial cycle results in a high dimensional stability in respect of changes of temperature and humidity.Even large variations in the content of moisture, however obtained with forced experimental procedures, thatdon’t occur in current use of the product, involves small variations in size of 0,033 mm/m (drying shrinkage).The coefficient of linear thermal expansion is 5x10-6 K-1 for the dry material, thus comparable to traditionalbuilding products.

Mechanical strength and thermal insulation CLC has a porous structure (micro and macro pores). The amount of porosity is controlled by the producer inthe formulation stage of raw materials and this involves a control of the density of the final product. Thedensity is, in turn, correlated with the technical specifications. For example, it increases results in animprovement of mechanical strength but, on the other side, in a deterioration of insulation. In order to meetthe needs regarding the most recurring implementations in the construction industry without running the riskof distorting the features that mostly enhances the material, elements with a density of 400 to 600 kg/m3 andthe following features are produced:

Resistance to average compressive strength on the elements of 1.4÷2.5 N/mm²; Thermal conductivity on the elements and on a finished wall of 0.09÷0.175 W/mK -, Modulus of elasticity on "E" tests of 2600 N/mm².

The resistance to traction is about 20% of resistance to compression. The use of lime in the mixture greatlyenhances this value, without compromising the resistance to compression.Concerning the potential of this material in the field of bearing walls, CLC is a material with an excellentbalace between mechanical resistance and specific weight. This is not true for traditional building productsand this feature is more evident when compared to finished building elements, whose siting benefits from theuse of CLC, as well as the installation of blocks with thin layers of adhesive mortar.

Thermal inertia The phase shift, or lag "R(H)", is the time from the moment when the outer face of a wall radiated by the sunreaches the maximum temperature, to when the inner face of it reaches the maximum temperature. Thedamping of the temperature variation is the relationship between internal and external variation oftemperature of a masonry radiated by the sunBoth parameters are a function of mass, thermal conductivity, specific heat and thickness of the wall. Calculations supported by experimental findings showed that a CLC wall with a thickness of 25 cm, a densityof 500 kg/m³ and λ =0.14 W/mK, has a phase shift R(H)=7.21 and a damping of 27.86. These values showexcellent properties of thermal inertia and environmental comfort arising from the use of this material. Another consideration to be noted about the behaviour of CLC with regard to thermal insulation is that theexperimental value of thermal conductivity is the same both on the element and on the finished wallcomposed of elements linked with adhesive mortar. This is due to the fact that the joints of the blocks are sosmall in thickness (1-1.5 mm) to render irrelevant the generation of the thermal bridge, as it happens,instead, with traditional technologies needing mortar joints with a thickness of at least 15 mm.

Soundproofing The sound insulation is typically heavily influenced by structural details. The CLC wall, if well designed, canachieve significant values for this type of insulation. The excellent sound insulationproperties come from the porousstructure, which reduces the soundpressure by over 30%. A CLC wall with a thickness of 12.5 cmand a density of 500 kg/m3, at 500 Hz,has an insulation value of 41 dB and aspecific surface weight of 70 kg/m2. Toachieve such a value with a brick wall, amass of 160 kg/m2 of specific surfaceweight is needed, which means a 18 cmfull wall or an over 25 cm perforatedbrick wall.

Vapor permeabilityThe remarkable vapor permeability ofCLC (μ = 6.9), resulting from the microand macro porosity of the structure,means great comfort. Under normalconditions of humidity and temperature,the flowing stream of water vapor movesfrom inside to the outside of buildings.The vapor permeability, besidesproviding well-being and environmentalcomfort, translates into a betterbehaviour of the product in terms oftemperature and humidity, because it avoids the stagnation of interstitial condensation, which causesdegradation of the insulating performance of all materials.

Fire resistanceCLC is a building material made of cement and is free of Inorganic binders. That is why, in accordance withcurrent legislation, it was given the Zero (0) fire reaction class without any experimental proof.A wall can be described as fire resistant (REI) for a given amount of time (120' or 180') when it respondspositively to a specific laboratory test consisting in exposing a face of a real wall to open flames, until theface reaches a temperature of 1100 degrees. Then, in addition to the static sealing, the temperature notexceeding 150° on the opposite side and the absence of smoke and flame passage are verified.A not plastered CLC wall is found to be REI 120 for the thickness of 7.5 cm and REI 180 for the thickness of10 cm. CLC is then the only material capable of achieving this performance for thicknesses as small and withoutplaster: a 30 cm plastered brick wall is REI 180.

T

thickness 20 cm HD heat diffusion

Environmental featuresCLC is a mineral product and is environmentally friendly because, even when led to rapid combustion withflame, or to slow combustion flameless, does not give off harmful gases to human health, but only water

the sound emerging

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abs

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sound

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880°

A B

20°

HD hours 0,30 HD hours 1,00

25°

A B

990°

HD hours 3,00

30°

A B

1100°

HD hours 6,00

40°

A B

1160°

T T T T

vapor, due to a normal moisture content in the material, as it appears on the certificates of fire resistance.Also, when irradiated by gamma rays or noble gases, it has not radioactive charge.

Frost resistanceIn common applications, for normal moisture content within the material, CLC, even when subjected toseveral cycles of freezing and thawing, has no alteration, which is also confirmed by its extensive use in coldcountries.Ultimately, the high technical standards that the cellular concrete is able to provide, offer great opportunitiesin construction, both residential and industrial. The growing application of this material can allow theachievement of higher and higher building performance and comfort levels, together with a superiorenvironmental sustainability for both the materials used and their combination and the total recyclability ofthe finished product. There are no production waste, because residues and scraps (for example: cuts duringproduction or waste in the installation) can be ground and reused in the dough even in high percentages,subject to the quality of the sand and the final density to be achieved.

Casting on site (MONOLITHIC System)

It is a Building technology with structure in light steel frame, formwork to lose and fills with CellularLightweight Concrete (CLC), for “Monolithic” construction on-site. The construction is called “Monolithic” because, in addition to the type of castings filling, which provideunique phases to each plane of the dwelling, as well as for floors and roofing, steel frame is completelyconnected to all its parts and sections of the dwelling: walls perimeter, partitions, floor and roof. Therefore,the structure is a single body with a box-like behavior, without points of discontinuity or connecting orfastening.As for the thermal insulation, the possibilities offered by this technology are the most diverse. For instance,when meet special or strict requirements in terms of transmittance of vertical and / or horizontal, where theexceptional thermal properties of CLC do not satisfy the requirements depending on the thicknesses of theproject, it is extremely easy and practical to resort to the application of a layer of insulation (ex. EPS, rockwool, etc.) on the internal face and / or exterior of the metal frame before the shuttering and subsequent castof the CLC. The walls thus produced are then shaved or plastered as normal insulation (traditionally insteadmade second phase of construction of the building).

STEEL FRAMEThe main structure will consist of galvanizedsteel profiles suitably shaped with dimensionsto the thickness of functional design of theouter walls and partitions, and connected toeach other with screws or rivets structural. Areal cage made up of the mirrored covering,floors and roofs including, of course integral tothe foundation slab.The mirrored covering is a flat surface portionon the perimeter of which was placed a metaland is located within the cellular concrete,confined by the metal frame.This element has a very strong resistance dueto the peculiarity that the concrete placed in ametal frame can explain the most of itsstructural function.As well known by science and structural engineering, concrete is a material that is not resistant to tractionbut has excellent performance in compression, circumscribed in a durable frame it allows to avoid thetension and make the most of its features compression.

Advantages of using the Steel Frame.Profitable and quick to build.The construction is simple, fastand accurate, because all thecomponents are manufacturedoff-site with forming machinesoperated by CAD / CAM systemthus ensuring extreme precisionof all connections, thendisplayed in diagrams anddescriptions mounting. Thismeans high quality results inany place, even using low skilled labor at low cost, and shorter times. The executive project provides full parts list, with particulars of the holes that allow the passage of the CLCfilling.The profiles are assembled by use of screws or rivets structural.A single wall can also be mounted outside the work and then positioned and connected to the load-bearingwalls and the partition walls.Design flexibility. The inherent strength of the steel allows flexibility and architectural design by encouragingdesigners to think outside the square and make the most of the space available, lending itself perfectly todesign innovative and unconventional lines.Durable and safe. Thanks to exceptional fire resistance, corrosion and pests, steel framed buildings are thefirst choice for even extreme environmental conditions. Since the steel does not need to be treated withpesticides, preservatives or glues, guarantees maximum safety for the people who manipulate, who live orwork around it.Environmentally friendly. The steel frame lasts longer, it is lightweight and easy to carry and build theminimum waste of raw material. At the end of its long life it can be completely recycled. It is the single mostrecycled material in the world.Fire resistant. Housing components in Steel frames have been tested and proven to withstand hightemperatures of fire directed over 1000 ° C. Seismically tested. The strength and ductility of steel, combined with the engineering and design firm, makea safe choice in earthquake zones. For the same reasons also it has a high resistance to wind pressure,having the ability to bend or deform without breaking and being thus able to absorb and amortize these typesof energy. In summary earthquake protection is dealt with according to a design philosophy that accepts the entry intothe plastic range of the structure, using it as a technique of passive protection by the earthquake, reducingstiffness and increasing the energy dissipated with consequent reduction of inertia forces suffered thestructure, without this collapse. Provided that it is "ductile"!

FORMWORKS

Containment system of the casting made of sheets to lose prefabricated in CLC special high-strength,constituting an ideal compromise of resistance to hydrostatic pressure, together with lightness andmaneuverability. They can also be used Magnesite commercial slabs, Fiber cement, etc.

slab formwork CLCdensity 1000 kg/m³

base profile

CLC density 400 kg/m³

transverse profiles

vertical profiles

foundation slab

Traditionally they are used formwork modular plastic, wood or sheet metal. This involves very hard-working,restrictions on the use of cranes according to the dimensions and weight, consumables (i.e.: the spacers)and also handling operations are repeated 2 times (assembly and disassembly). The finished wall never occurs to uniform appearance, in addition to the presence of holes in the rods of theformwork. Moreover, with time, the structural settlings and deficient homogenization with the reinforcing bars(not comparable with the use of structural concretes), will result in inevitable formation of cracks, often not beoffset by smoothing with cement mortar and sand. In the case of our technology, the structural settlings are amortized and offset by the coupling joints of theslabs, guaranteeing the total absence of future cracks.Slabs formwork can be self-produced with a line of low-cost production and special mix design to ensurestrength and lightness, but you can also resort to buying cement sheets if present on the local market, orimport them from the nearest country.

Ease of handling of slabs formwork.A slab of dimensions 75x60 cm (such as thoserepresented in the pictures) weighs 9 kg if thick 2cm and 13.5 kg if of thickness 3 cm, with CLCdensity of 1000 kg/m³.The positioning is very rapid, they are screwed tothe profiles and the joints sealed with adhesivemortar with low elastic modulus (can be self-produced on the basis of our directions withcement, sand and suitable additives).After completing the filling jets you do not havethe burden of dismantling and cleaning offormwork to recovery ... and no trifles!

The inner and outer walls thus constructed, must be protected and finishedby the application of networks by plaster fiberglass and with smoothingmortars, based acryl-siloxane for the exterior. The finishing can be smooth orrough as shown in the picture

They can also be made mold plates with architectural drawings in relief, coloring them with products andwaterproofing impregnating with high capillary penetration, with excellent results in terms of aesthetics andquality.

CASTING CLC

The cast on-site is performed with the aid of special equipment specially made for mobile use, and can be of2 types: Type Compact independently run, in the sense that knead and pump the CLC in the walls and / or

screeds. In a single machine are included foam generator, mixing tank, pump, balance, and generalelectrical panel. As shown in the figure (social House in Zimbabwe, city Harare), the machine can betransported to the site on a truck and supplied with cement and sand with a light load system in theaugers, the necessarywater of 1000 liter tankscarried by the truck itself.

With continuous system.Technology composed bya mixer with foamgenerator, and mono-screw pump incombination with TruckMixer that prepare theslurry (water-cement-sand). The foam will beintroduced directly into thepumping line. With thissystem, the casting iscontinuously, increasingthe production capacity, isthe most suitable for large production volumes.

With both systems are also thrown SCREEDS: Type traditional leveling density 1.800 ÷ 2.000 kg/m³ Structural lightweight leveling with expanded clay Lightened in CLC density variable up to a minimum of 300 kg/m³ (self-leveling) Lightened with polystyrene beads of varying density 250 to 800 kg/m³ and directly Tileable (leveling and

not) No self-leveling for easing of pitched roofs (with polystyrene beads, pumice, expanded clay).

Reference regulationsLaw of 5 November 1971 n.1086Norms for the discipline of the works in reinforced concrete, prestressed concete and metal structure.Law of February 2, n. 64Provisions for buildings with special requirements for seismic zones.Ministerial Decree of 14 January 2008Technical Standards for Construction.Ministerial Circular of February 2, 2009 n. 617.Instructions for the application of the "Technical standards for the buildings” referred to Ministerial Decree January 14, 2008EUROCODE 3 part 1-3In addition, reference is made also to the following Laws/Regulations Italian:Seismic Classification: ORDER 3274 2003Calculation method: linear dynamic analysis with response spectraLIMIT STATES Ministerial Decree of 14 January 2008 - TECHNICAL STANDARDS FOR CONSTRUCTION