Introduction and History

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1 Introduction and History

2 Page 2 (ERASE) Page 3 * BASIC CONCEPTS CHEMISTRY OF CONSTRUCTION - CONCEPTS / DEFINITIONS BINDERS - LIME (product manufacturing, chemical, cured) - CEMENT (product manufacturing, chemical, cured) HARMFUL SALTS - COMPOSITION - PROPERTIES Page 4 (ERASE)

Page 5 CHEMISTRY OF CONSTRUCTION BINDER / LIMES FOR THE CONSTRUCTION Lime mine (Pict.) The lime for construction is a binder used in works such as building material.

3 Page 5 CHEMISTRY OF CONSTRUCTION BINDER / LIMES FOR THE CONSTRUCTION Lime mine (Pict.) The lime for construction is a binder used in works such as building material. It is used for the preparation of basic lime mortars for masonry or plaster mortars. In the area of application for the improvement of areas of land, construction lime can be used for soil stabilization. Moreover is added to different types of cements to modify these properties. Lime for construction single used, once cured, has less than a mortar cement-based bonding strength. During the manipulation with limes for the construction must be taken into account, that this material is highly alkaline ( ph- value 13) and can cause irritation / skin burns. From according to the rules, the limes for construction differ basically between air lime and hydraulic limes. Air limes need the influence of air to cure. Hydraulic limes also can dry without the influence of the air, as for example under the water, and is commonly referred to as as water lime. Air limes are different at the same time among white lime (abbreviation CL) and dolomitic lime (abbreviation DL).

4 Page 6 CHEMISTRY OF CONSTRUCTION BINDER / LIMES FOR THE CONSTRUCTION HYDRATION To hydraulic limes (abbreviation HL) added the subgroup of the natural hydraulic limes (abbreviation NHL). If these limes adds hydraulic element Pozzolan the material receives the designation of natural hydraulic lime with Pozzolanic additives (abbreviation NHL-Z) The development of lime for construction from limestone and volcanic earth is already known since antiquity and has not changed much in its basic composition. Air lime is obtained from limestone, which burns at a temperature of approx. 900 C and then will be slake. Carbon dioxide is released during the burning process. Calcium oxide is obtained. For slake, water is added to calcium oxide. In this way it becomes calcium hydroxide. Curing occurs when calcium hydroxide and the carbon dioxide from the air are combined. This process is part of the technical cycle of lime.

aluminates. For the curing is not necessary the intervention of the air.

5 Page 7 CHEMISTRY OF CONSTRUCTION BINDER / LIMES FOR THE CONSTRUCTION Neuschwanstein castle (Pict.) Hydraulic lime is generated from the mixture of calcium hydroxide with adequate elements, such as calcium silicates and calcium aluminates. For the curing is not necessary the intervention of the air. Instead the performance of hydraulic elements (so-called hydraulic factors), such as silicates, aluminates and iron oxides, allow curing. Rules and standards at DIN -EN Limes for the construction Limestone (Pict.) Lime (Pict.)

6 Page 8 CHEMISTRY OF CONSTRUCTION - LIME CYCLE Decomposition above 898 C Burn the lime Calcium oxide Quicklime CaO Calcium carbonate formerly: acid carbonate of lime In the nature: in egg shells, shells of molluscs, etc... CaCO3 At 580 ºC Lime slake Very exothermic DH=-67kj/mol Calcium carbonate Set in lime mortar formerly: acid carbonate of lime In the nature: in egg shells, shells of molluscs, etc... CaCO3

carried out in large factories, which is manufactured

7 Page 9 CHEMISTRY OF CONSTRUCTION PORTLAND CEMENT It is usually a grey powder, which is obtained in processes carried out in large factories, which is manufactured from materials such as limestone, clay, sand and iron ore.

Page 10 CHEMISTRY OF CONSTRUCTION Furnaces of Joseph Aspdin (Pict.) Portland Cement History As inventor of the cement Portland is considered Englishman Joseph Aspdin (1778-1855).

8 Page 10 CHEMISTRY OF CONSTRUCTION Furnaces of Joseph Aspdin (Pict.) Portland Cement History As inventor of the cement Portland is considered Englishman Joseph Aspdin ( ). In 1824 obtained the patent for An improvement in the mode of producing an articial stone, in which he first used the term "Portland cement. This was not a cement in the form we know it today, but an artificial Roman cement. The meaning of the sintering process is attributed to Isaac Charles Johnson ( ), who recognized him in the year 1844, who with their improved process introduced the 'authentic', on burning Portland cement in the construction industry, in which and due to its extreme hardness quickly displaced the Roman cement.

Page 11 CHEMISTRY OF CONSTRUCTION The factory of Portland cement in Itzehoe, around 1895 (Pict.) Portland cement - History In 1838 was founded in Ulm the first cement factory by the pharmacist Dr.

9 Page 11 CHEMISTRY OF CONSTRUCTION The factory of Portland cement in Itzehoe, around 1895 (Pict.) Portland cement - History In 1838 was founded in Ulm the first cement factory by the pharmacist Dr. Ernst Gustav Leube and his brothers. The first German factory of cement Portland's agreement to the originating English was built in 1850 in Buxtehude. The basis for the manufacture of cement in Germany were sitting by Hermann Bleibtreu ( ), which also built two factories of cement, one in Züllchow in Stettin (1855) and the other at Oberkassel in Bonn. Wilhelm Michaelis ( ) had a decisive influence on the subsequent development. In his book published in 1868 under the title "Hydraulic mortars", as first detailed accurate data for the more economical composition of the primary elements of the mixture.

10 Page 12 CHEMISTRY OF CONSTRUCTION BINDER / CEMENT Cement is a finely ground, inorganic, non-metallic element which, when mixed with water, and as a result of chemical reactions with the mixing water produces a process of self curing and hardening; after it hardens also stays stable and non-deformable under water. From the purely chemical point of view, the cement is a silicic acid of calcium, with parts of aluminium and iron, which is presented as a complicated elemental mixture. In general, it also presents parts of sulfates. Page 13 CHEMISTRY OF CONSTRUCTION BINDER / CEMENT The most important application area is the preparation of mortar or concrete, i.e. the union of artificial or natural elements to get a construction material, highly resistant to the harshness of the environment... In the wake of the durability and high resistance of the concrete, cement is worldwide one of the most important binders used. Page 14 CHEMISTRY OF CONSTRUCTION HYDRATION OF CEMENT Curing and hardening of cement is based on the formation of aqueous combinations, which are generated in the reaction between cement components and mixing water. General cement reacts in a low-water relationship, such as a plastic mixture with a ratio water - cement (value W / Z) between 0.3 and 0.6. The reaction is called hydration, resulting as hydrates or hydrated phases products.

Page 15 CHEMISTRY OF CONSTRUCTION HYDRATION OF CEMENT A consequence of the initial reactions is a rigidity of the paste of cement, mild at the beginning but that is strengthening with the passage of

The aftermath of the rigidity of the cement paste is called solidification, solidification period referred to as hardening.

11 Page 15 CHEMISTRY OF CONSTRUCTION HYDRATION OF CEMENT A consequence of the initial reactions is a rigidity of the paste of cement, mild at the beginning but that is strengthening with the passage of time. When a certain rigidity of the cement paste point is reached, it is start of solidification. The aftermath of the rigidity of the cement paste is called solidification, solidification period referred to as hardening. Page 16 CHEMISTRY OF CONSTRUCTION HYDRATION OF CEMENT The cause of the stiffness, solidification and hardening is training in greater or lesser degree of rigid structures of hydration products, which fill the space occupied by water between the solid particles of cement, mortar or concrete paste. The temporal development, but not the kind of hydration products, depends primarily on measure spaces, i.e. value water - cement. Page 17 CHEMISTRY OF CONSTRUCTION - DEVELOPMENT OF CEMENT PORTLAND CEMENT Approximate equilibrium of the reaction LIMESTONE + CLAY AT ºC Slag Portland cement: C 3S + C 2S + C 3A + C 4AF

12 Page 18 CHEMISTRY OF CONSTRUCTION Carbonation, hydration CO 2 + H 2O << >> Ca(OH) 2 + [ H 2CO 3] >>>> CaCo 3 + 2H 2O Page 19 CHEMISTRY OF CONSTRUCTION Carbonation, hydration Page 20 CHEMISTRY OF CONSTRUCTION Carbonation, hydration 2 C 3S + 6 H >>>> C 3S 2H 3 + 3CH Alit Afwillit C 2S + 2 H >>>> CSH + CH Belit

13 Page 21 CHEMISTRY OF CONSTRUCTION Carbonation, hydration

14 Page 22 Mengenanteil = Mixing ratio

15 Page 23 CHEMISTRY OF CONSTRUCTION Expansion of the ettringite C3AH6 + 3Cs + 26H C3A (Cs)3 H32 Ettringite Page 24 Page 25 PICTURE

Page 26 CHEMISTRY OF CONSTRUCTION Hydration of cement The ettringite (also called woodfordite) is a rare mineral of the

It crystallizes in the monoclinic crystals with the following composition system: Ca6Al2[(OH)12 (SO4)3] 26 H2O And usually

It is also known as white satin or salt of Candlot as synthetic by-product.

16 Page 26 CHEMISTRY OF CONSTRUCTION Hydration of cement The ettringite (also called woodfordite) is a rare mineral of the mineral group from aqueous sulphate with anions. It crystallizes in the monoclinic crystals with the following composition system: Ca6Al2[(OH)12 (SO4)3] 26 H2O And usually develops well-defined crystals, either binocular or needles or pseudo hexagonal, yellow color, but may also be white. It is also known as white satin or salt of Candlot as synthetic by-product. The representation of the formula for the sum of elements used in the chemistry of the construction is as follows : 3CaO Al2=3 CaSO4 32 H2O Page 27 CHEMISTRY OF CONSTRUCTION Chemical corrosion Loss of binder by transformation of binder in soluble salts (solvent attack)

Page 28 CHEMISTRY OF CONSTRUCTION Chemical corrosion Often attached to a volume expansion = propeller attack Page 29 CHEMISTRY OF CONSTRUCTION Salt crystallization CaCO 3 + H 2SO 4 + 2 H 2O >> CaSO 4

17 Page 28 CHEMISTRY OF CONSTRUCTION Chemical corrosion Often attached to a volume expansion = propeller attack Page 29 CHEMISTRY OF CONSTRUCTION Salt crystallization CaCO 3 + H 2SO H 2O >> CaSO 4 x 2 H 2O + CO 2 + H 20 +/- 100 % (Calcite) (Plaster) MgCO 3 + H 2SO H 2O >> MgSO 4 x 7 H 2O + CO 2 + H 2O +/- 430 % (Magnesite) (Epsom salts) FeCO 3 + H 2SO 4 + 7H 2O >> FeSO 4 x 7 H 2O + CO 2 + H 2O +/- 480 % (Siderite) (Ferrous sulphate) Al 2O H 2SO H 2O >> Al 2(SO 4) 3 x 18 H 2O +/ % (Clay) (Aluminium sulphate)

18 Page 30 CHEMISTRY OF CONSTRUCTION Salt crystallization Page 31 BASIC CONCEPTS Physics of construction - Concepts / Definitions Pores - Types, size - Typical measurements for moisture transportation * Hydrophility << = >> Penetrating sealer * Possibilities of penetrating sealer

Page 32 PHYSICS OF CONSTRUCTION Pores space Table Poren = Pores Untersuchungsmethoden = Research methods Verdichtungspohren = Pores of compaction Auge = Eye / Visual

19 Page 32 PHYSICS OF CONSTRUCTION Pores space Table Poren = Pores Untersuchungsmethoden = Research methods Verdichtungspohren = Pores of compaction Auge = Eye / Visual Luftporen = Air voids Mikroskop = Microscope Kapillarporen = Capillary pores Elektronenmikroskop = Electron microscope Gelporen = Gel pores Indirekte Methoden = Indirect methods

20 Page 33 PHYSICS OF CONSTRUCTION Pores space (air voids) Page 34 PHYSICS OF CONSTRUCTION Pores space (air voids)

adding water b) grain of cement shortly after adding

21 Page 35 PHYSICS OF CONSTRUCTION Capillary pores Page 36 CEMENT Pores space a) grain of cement before adding water b) grain of cement shortly after adding water c) end of the hydration Page 37 CEMENT Pores space

Page 38 CEMENT Ettringite / Pores space Cement hydration / Expansion of the ettringite In the initial phase of the development of the binder, the production of ettringite, is desirable to counteract

22 Page 38 CEMENT Ettringite / Pores space Cement hydration / Expansion of the ettringite In the initial phase of the development of the binder, the production of ettringite, is desirable to counteract the rapid processes of hydration of the binder. But also after the hardening of the concrete mixture, it can produce a transformation of mono-sulfate to ettringite. This process is accompanied with an increase in volume of up to three times and is known by the name of expansion of the ettringite. This is usually generated by the intrusion of water with high sulphate content. The typical form of the presence of the ettringite are its isomorphic growth needle-like crystals. But the effect of the expansion of the ettringite is essentially based on the extreme multiplication of the volume of water gel, crystals are a side effect resulting from the drying process.

23 Page 39 CEMENT Pores space Wasser = Water Zementkorn =Cement grain Hydratation = Hydration >>>>>>>>>>>>>>>>>> Wasserzementwert = Ratio water - cement w/z = 0,20; 0,40; 0,60 Kapillarporen ( Wasser) Capillary pores (Water)

24 Page 40 CEMENT Pores space Table Luftporen = Air voids Unhydratisierter Zement = Not hydrated cement Kapillarporen = Capillary pores Gelporen = Gel pores Zementgel(Feststoff) = Cement gel (solid element) Hydratationsgrad = Degree of hydration a = 1,0 Wasserzementwert = Ratio water - cement

25 Page 41 PHYSICS OF CONSTRUCTION Concrete Concrete / Binder cement Stone beads / measured sieve 0-16 (Pict.) Concrete is a mixture of cement, stone beads, or aggregates (sand and pebbles or gravel) concrete and mixing water. Can contain also other elements or additives. In combination with iron construction or prestressed steel, reinforced concrete or pre tensioned concrete can be obtained. The word "Beton" (concrete) comes from the French and was first mentioned by Bernard de Bélidor in a book of architecture.

26 Page 42 PHYSICS OF CONSTRUCTION Concrete Concrete / Binder cement Intrincate (Pict.) The cement made of binder to keep together all other components. The hardness of the concrete results from the crystallization of the part of the cement clinker, which is forms small needles that are embedding including The crystals growth continues for months, so that the final hardening is obtained long after the dumping of concrete. But splitting rules, such as those contained in DIN 1164 (kinds of hardening of cement), by which under normal conditions of temperature and humidity, according to the hardening is obtained at 28 days.

27 Page 43 PHYSICS OF CONSTRUCTION Concrete Concrete / Binder cement Concrete artificial stone has two particular temporal properties. First, presents a reduction in volume or shortening following drying, also known as reduction. Second, deforms under the weight without an increase in weight, usually called drag.

28 Page 44 PHYSICS OF CONSTRUCTION Concrete Concrete / Binder cement Damage of concrete by breaks of frost or corrosion (Pict.) Most of the water is not removed by drying, but it focuses on the concrete as crystallized water. This means that the concrete does not dry, but rather that bind. Means that the initial cement liquid paste (cement water) gets rigidity, solidifies, and finally hardens.

29 Page 45 PHYSISCS OF CONSTRUCTION - transportation of moisture First (1st) transport mechanism Diffusion Gaseous liquid Filled with air or water >>>>>>>>>>>>> Difference of concentration D C Page 46 (Ducks) ERASE?????

30 Page 47 PHYSISCS OF CONSTRUCTION - transportation of moisture Second (2nd) transport mechanism Capillary pipe Liquid Filled with air >>>>>>>>>>>>>>>> Surface tension Contact angle

31 Page 48 PHYSISCS OF CONSTRUCTION - transportation of moisture Maximum height > capillary suction (Pict.) Deduction: Capillary suction 2 Pc = R 1) A porous material absorbs water. 2) Small pores absorb water of large pores = free water remains among the free spaces

32 Page 49 PHYSISCS OF CONSTRUCTION - transportation of moisture Third (3rd) transport mechanism Laminar flow > Gaseous liquid > Filled with air or > water Page 50 IMPREGNATION Pressure difference D p

REPELLENT IMPREGNATION Wet a building material

33 Impregnation impraegnare = penetration / filtration the greatest possible penetration Page 51 WATER REPELLENT IMPREGNATION Wet a building material hydrophilic surface: - Good dampening - Small contact angle

WATER REPELLENT IMPREGNATION Page 53 WATER REPELLENT

34 Wet a a building material-hydrophobic surface: Page 52 - Little dampening - Big contact angle. WATER REPELLENT IMPREGNATION Page 53 WATER REPELLENT IMPREGNATION Moisturizing capillary ascension No moisturizer capillary depression

35 Page 54 WATER REPELLENT IMPREGNATION Secession of H 2 O molecules Drawning Drawning The water repellent treatment ========== Surface of material of construction not treated (with adsorbed water molecules) Surface of material of construction with water-resistant treatment (Well compacted Siloxan molecules and their repulsive molecular parts of water - here simplified as groups CH-3 - outsideoriented).

36 Page 55 WATER REPELLENT IMPREGNATION * The capillary activity is reduced - Valor w < 0,1 kg/ (m 2. h 0,5 ) * The diffusion capacity is unchanged - Value u slight increase - Value S d ( ux d ) slight increase Page 56 WATER ABSORPTION COEFFICIENT Water absorption coefficient w [ kg / ( m 2 x h 0,5 )] on a normal substrate according to DIN (1998) W < 0,1 kg / ( m 2 x h 0,5 ) W = 0,1 0,5 kg / ( m 2 x h 0,5 ) Water repellent e.g.: Resin silicone; Emulsion paints Water resistant e.g.: Dispersion and emulsion paints W > 0,5 kg / ( m 2 x h 0,5 ) Very permeable to water e.g.: Paints or emulsions based on lime Page 57 THE DIFFUSION CURRENT DENSITY OF WATER VAPOUR (permeability) DIN - EN ISO (1999) Difusion of steam: water transport in gaseous form in porous building materials.

37 Value S d [m] : Thickness of a layer of air at rest, which presents the same density of the diffusion current of steam to cover under the same conditions S d < 0,14 m high permeability to water vapour e.g.: Resin silicone, emulsifiers paints, lime paints S d = 0,14 1,4 m S d > 1,4 m intermediate permeability to water vapour e.g.: Synthetic or dispersion paints low permeability to water vapour e.g.: Oil paintings or lacquers Page 58 THE CONTROLL SERIES Our task? * How to act * Arguments

38 Page 59 THE CONTROLL SERIES * Controll Innerseal * How to act * Controll Topseal * Arguments Page 60 CONTROLL INNERSEAL Controll Innerseal has been manufactuerd to achieve an effective sealing of concrete. Controll Innerseal is used for the waterproofing in large industries, e.g.: the pillars of concrete of drilling rigs.

39 Page 61 HOW TO ACT Controll Innerseal penetrates deeply (up to about 20 cm.) on wet building material and reduces their ability to absorb water Surface tretaed with Innerseal

40 Page 62 HOW TO ACT Controll Innerseal generates a permanent barrier, permeable yet against moisture and corrosive chemicals. Crystallization of Innerseal 1

41 Page 63 HOW TO ACT Controll Innerseal chemically reacts with the lime Controll Innerseal acts by filling cracks Ca 2+ Chemical reaction with Further cracks are filled Innerseal in porous wall AL 3+

42 Page 64 HOW TO ACT Controll Innerseal It hardens Seals Refine Retain and sanitizing the concrete in a single procedure Page 65 HOW TO ACT Controll Innerseal use the valuable properties of the soluble sodium silicate for sealing concrete with an open diffusion. Unlike other sealants, which are applied as a sealed surface and cause a physical barrier on the concrete (e.g.: epoxies; polyester, polyurethane, acrylic or vinyl) Controll Innerseal penetrates deeply into the concrete and reacts with the calcium in the same form a hydrated calcium silicate gel: Na 2SiO 3 + y H 2O + x Ca(OH) 2 >>> x CaO SiO 2 y H 2O + 2NaOH

43 Page 66 HOW TO ACT Controll Innerseal Silicon gel hydrates below and it will gradually harden to form a pseudo-vitreous insoluble crystalline structure within the structure of the pores and the capillary system. As a result of this process are obtained improved properties of concrete as a reduction of permeability, hardness and in general a greater resistance. Through advanced production techniques, Betonseal technicians, with the help of experts have managed to develop sodium silicate truest of all time for use in the manufacture of our products. The average size of the particles in Controll Innerseal is 0.7 NM, where 20% of them are between 0.1 and 0.4 NM ( 1 Nanometre NM = 1/ mm ). Together with a special formula, which also includes calcium silicates (Ca 2SiO 4), confer to Controll Innerseal greater penetration for all products of sealed concrete present on the market. Page 67 HOW TO ACT It makes the concrete: Water proof resistant to acids, salts and oils and avoids at the same time the carbonation, corrosion and the efflorescence the attack of bacteria, algae and fungi and molds.

44 Page 68 CONTROLL TOPSEAL

45 Page 69 CONTROLL TOPSEAL A dry wall is warmer and prevents the formation of dew or fungi. >> Limit value of the dew point <<

46 Page 70 CONTROLL TOPSEAL Controll Topseal was developed as a product for sealing of surfaces It protects the concrete surface (up to a depth of approx. 60 mm) of exogenous attacks, such as the filtration of water, chemicals, salts and acids. Page 71 CONTROLL TOPSEAL Controll Innerseal y Controll Topseal are natural products made on the basis of Silicate of sodium and calcium (in the case of Topseal added potassium methylsilantriolate) with a special organic catalyst. They are colourless, odourless, non flammable and suitable for drinking water tanks. Controll Products can be used on any type of concrete

47 Page 72 Thanks for your attention Page Cologne www.

Wikipedia.org BUILDING STONES. Chapter 4. Materials of Construction-Building Stones 1

Wikipedia.org BUILDING STONES. Chapter 4. Materials of Construction-Building Stones 1 Wikipedia.org BUILDING STONES Chapter 4 Materials of Construction-Building Stones 1 What is Stone? Stone is a concretion of mineral matter. Used either as a; Construction material, Manufacture of other