CONCRETE SIKA VISCOCRETE AND RETARDAN ADDITIVES FOR DRY MORTAR INDUSTRY

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Gavin Hart
6 years ago
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1 SIKA VISCOCRETE AND RETARDAN ADDITIVES FOR DRY MORTAR INDUSTRY

GLOBAL PRESENCE, ACTIVE LOCALLY With a network of 160 offices in more than 90 countries, Sika is positioned not only globally, but also locally enabling global and local customer support.

In addition to concrete, screed, plaster and masonry mortar, floor levelling compounds, tile adhesive, grout and spray concrete, many specialties such as concrete repair mortars or fillers, sealing

2 GLOBAL PRESENCE, ACTIVE LOCALLY With a network of 160 offices in more than 90 countries, Sika is positioned not only globally, but also locally enabling global and local customer support. Dry mortar: For today and tomorrow Industrially prefabricated dry mortars are used in almost all applications in new buildings and refurbishment. In addition to concrete, screed, plaster and masonry mortar, floor levelling compounds, tile adhesive, grout and spray concrete, many specialties such as concrete repair mortars or fillers, sealing slurries, concrete filler and injection mortar are based on dry mortar technology. Individually developed dry-mix formulation ensure maximum security and allows the use of modern mixing and pumping equipment. Building materials with special properties represent a special challenge for dry mortar producers. Flowable, self-levelling screeds and underlayment s or plaster with a controlled setting profile are already standard. Also in the future, the number of dry mortar products and applications will require several innovations. With more than 40-years experience in concrete admixture, Sika is a competent partner for the dry mortar industry. We are motivated to offer sustainable, environmentally compatible and cost-effective solutions. Dry mortars are complex systems. Even the change of only one component, such as the superplasticizer, may make the adaption of other parameters necessary. Sika provides individual support, i.e. in the Sika Technology Center in Leimen (Germany), where appropriate preliminary tests can be performed. Individual customer solutions Customer interaction and support is one mayor component of Sika's company philosophy. Competent and individual product recommendation Preliminary tests in Sika mortar laboratory Adaptation of customer mixtures Tailored additive compounds Application support on site Experienced laboratory employees Global network of specialists Since 2008, Sika provides its superplasticizer Sika Visco- Crete and gypsum retarders Retardan in powder form and thus provides dry mortar manufactures with new opportunities. 2

SUPERPLASTICIZERS Sika ViscoCrete based on PCE (polycarboxylate) technology, was introduced in the early 2000s and has been continually developed.

The production, following demanding industrial standards, ensures a continuously high product quality.

3 SUPERPLASTICIZERS Sika ViscoCrete based on PCE (polycarboxylate) technology, was introduced in the early 2000s and has been continually developed. Today, Sika is a leading producer of PCE-based plasticizers, with 20 ViscoCrete production sites worldwide and international experience in countless applications. The production, following demanding industrial standards, ensures a continuously high product quality. Slump flow Examples for consistency curves of various PCEs Water Reducing ViscoCrete Polymers Slump Controlling ViscoCrete Polymers Slump Controlling ViscoCrete Polymers time Sika ViscoCrete superplasticizers have a double-action dispersion effect: by saturation of electrostatic charges on the particle surface by steric repulsion of the PCE molecules. The comb polymer structure of Sika ViscoCrete was designed to achieve application-specific properties. Polymer specific properties such as backbone chemistry, backbone length, number and length of side chains and charge density have a direct impact on the performance in the respective application field, such as water reduction, workability time, rheology, strength development, air content and adsorption time. By understanding the effect of different polymer designs, Sika is able to offer tailor-made solutions for many applications with different binders! Benefits Up to 10-times lower dosage compared to traditional superplasticizers Short mixing times Allows significant water reduction Long consistency preservation / workability Less shrinkage (up to 30 %) Good price performance ratio Good compatibility and synergy with other additives No release of ammonia (vs. casein) No release of formaldehyde (vs. melamine and naphthalene) Sustainable and available worldwide development ViscoCrete -510 P P Even faster adsorption Ideal for mechanical mixing- and conveying technology ViscoCrete -510 P very broad spectrum of applications ViscoCrete -520 P especially for ternary systems Improved workability by steric repulsion 3

4 RETARDERS FOR GYPSUM BASED DRY MORTARS Retardan additives are very effective retarders in liquid or powder form, used for decades in the gypsum industry. They show excellent performance in the adjustment of the setting and workability time in a variety of calcium sulphate binders, also in combination with other additives such as rheological additives, foaming agents and accelerators. They are characterized by a very low dosage and a high retarding effect in different gypsum binder systems. Retardan is noted for its well-defined retardation. Comparison of the retardation curve Setting time Retardan Setting time Tartaric acid Setting time Citric acid Setting and strength development [%] Time [time units] 5 Benefits Shift the start of hydration without loss of intensity No negative effect on the gypsum crystal growth (contrary to fruit acids) Fast strength development and higher final strengths Low dosage Compatible with citric and tartaric acid Very robust against changes of ph value Optimal control of the retardation curve Consistent quality due to controlled production Test conditions: Constant retarder dosage, alkaline environment 4

APPLICATION EXAMPLE VISOCRETE ANHYDRIT LEVELLING FLOOR SCREED The market share of flowable screeds in Germany is already at about 25 % and will increase in the future.

Sika ViscoCrete shows even at very low dosage excellent liquefaction performance in levelling screeds and is compatible with other additives such as the retarder Retardan.

Material: Binder mixture of natural and synthetic anhydrite.

5 APPLICATION EXAMPLE VISOCRETE ANHYDRIT LEVELLING FLOOR SCREED The market share of flowable screeds in Germany is already at about 25 % and will increase in the future. Very simply installation due to the almost self-compacting properties and even surfaces are the main advantages. Sika ViscoCrete shows even at very low dosage excellent liquefaction performance in levelling screeds and is compatible with other additives such as the retarder Retardan. Compared to melamine, usually less than 25% of the original dosage is required. Mission: Reformulation to a very low emission recipe by replacing melamine to PCE. Material: Binder mixture of natural and synthetic anhydrite Easy surface finishing 2 Convenient installation while standing 3 Higher installation rates feasible 3 Screed dry mortar without superplasticizer [g] Dosage of superplasticizer [g] Reference ViscoCrete -225 P ViscoCrete -510 P ViscoCrete -510 P Water [ml] Initial flow Hägermann 2 min [cm] Initial flow Hägermann 30 min [cm] Strength 7 d (F/C) [N/mm²] Strength 28 d (F/C) [N/mm²] / / / / / / / / 22.6 Solution: To achieve similar fresh and hardened mortar data compared to the reference, only about 13% of the original melamine dosage is needed; with 20% of the original dosage, a water reduction associated with about 10% higher strengths are achieved. 5

APPLICATION EXAMPLE VISOCRETE GROUTING MORTAR Grouts are used during installation in new buildings and in refurbishment, in building construction, civil engineering and engineering.

Grouting of rails or mounting plates, connection of prefabricated, reinforced concrete and backfilling of sleeve foundations are just some of the possible applications.

6 APPLICATION EXAMPLE VISOCRETE GROUTING MORTAR Grouts are used during installation in new buildings and in refurbishment, in building construction, civil engineering and engineering. They are mainly used in safety related areas. Grouting of rails or mounting plates, connection of prefabricated, reinforced concrete and backfilling of sleeve foundations are just some of the possible applications. Very special demands are made on highly dynamically stressed grouts for wind power stations in offshore and onshore areas. Due to these different applications continuously new and improved developments are required also up in the high strength range. Different qualities of cement and special additives are the major challenges for the mortar formulation. Fast adsorption to a high initial flow associated with a long slump keeping without additional liquefaction is required. Mission: Optimize fresh mortar on a target value of 245 mm ± 5 mm Hägermann consistency drop after 2 hours <10%. Fast adsorption to a high initial flow associated with a long slump keeping without additional liquefaction. Material: Cementitious grout Solution: None of the tested superplasticizer fulfills the requirement stated above alone. The combination of a strong water reducer with a slump keeper gives the optimal solution. 1 Flow channel for grout 2 Flow rate with Hägermann 3 Perfect flow properties 4 SLU application Flow over time Slump flow Hägermann [mm] Time [min] Sika VC-430 0,03% Sika VC-510 0,03% Sika VC-150 0,03% + VC-430 0,03% Sika VC-510 0,03% + VC-430 0,03% Competitor 0,03% Competitor 0,03% 2 6

APPLICATION EXAMPLE VISOCRETE SELF-LEVELLING UNDERLAYMENT (SLU) Flow over time and viscosity of the mixture 160 79 140 78 77 3 Slump Flow EN-Ring [mm] 120 100 80 60 40 76 75 74 73 72 71 70 Flow time

1 % on total Initial flow EN-ring [mm] Flow EN-ring 30' [mm] Flow time Fordcup [sec] With the installation of floor coverings, a flat, evenly absorbent substrate is required.

7 APPLICATION EXAMPLE VISOCRETE SELF-LEVELLING UNDERLAYMENT (SLU) Flow over time and viscosity of the mixture Slump Flow EN-Ring [mm] Flow time Fordcup [sec] Reference Sika VC-225 P Sika VC-510 P Sika VC-520 P 68 All superplasticizers with dosage 0.1 % on total Initial flow EN-ring [mm] Flow EN-ring 30' [mm] Flow time Fordcup [sec] With the installation of floor coverings, a flat, evenly absorbent substrate is required. Self-levelling compounds fulfill these tasks. They must be tailored to the particular substrate and floor covering. Excellent flow properties and rapid drying for floor covering application are the key arguments for the floor layers. The use of special mixing and pumping equipment is getting more and more into the focus of the mortar developers. Sika ViscoCrete Superplasticizer shows especially here good liquefaction performance. Mission: Replacement of an existing PCE with comparable flow properties for mechanical mixing and conveying technology. Material: Ternary, CAC-rich floor levelling compound, ph <11.5 Solution: The new VC-510 and VC-520 shows the highest initial flow and the best slump keeping of all tested ViscoCrete types. ViscoCrete -520 P is also characterized by low mortar viscosity and high mortar strengths. The 1:1 replacement is possible and even leads to quality improvements. 4 7

8 APPLICATION EXAMPLE RETARDAN GYPSUM PLASTER Setting profile by ultrasound Velocity [m/s] Velocity [m/s] Time [minutes] Time [minutes] Gypsum-lime lightweight plaster with Gypsum-lime lightweight plaster with 0,06% Tartaric acid/ 0,06% Phosphate retarder 0,06% Retardan P/ 0,06% Tartaric acid 0,03% Retardan -200P/ 0,03% Tartaric acid 0,03% Retardan P/ 0,03% Tartaric acid Reference Curve (insufficient retardation) 0,06% Retardan P/ 0,06% Tartaric acid/ 0,06% Phosphate retarder 0,03% Retardan -200P/ 0,06% Tartaric acid/ 0,06% Phosphate retarder Combination of 2 retarders: The different retarder combinations show a steep setting curve, except the combination with the phosphate retarder. Combination of 3 retarders: With the combination of tartaric acid, Retardan and phosphate retarder an ideal setting curve is achieved Gypsum plaster or gypsum-lime plaster is at present the most frequently used interior plaster. Easy application and a consistent setting behavior are critical for the success of the user. Retardan is especially suitable as a setting regulator for use in gypsum plaster through the large ph-tolerance. It can be optimally combined with other retarders e. g. fruit acids. Mission: Set the processing time with Retardan Material: Gypsum-lime lightweight plaster, ph approx (mixed with 10 % water) The ideal setting curve is reached by a combination of Retardan, tartaric acid and phosphate retarder. After spraying the plaster is levelled with the metal straight edge perpendicular and flush right. Once the stiffening begins after about 90 minutes, ridges and tracks are pulled out with the trowel. After about 3 hours, when the plaster is sufficiently stiffened, the surface can be wetted slightly and felted by using a sponge float. After another 30 to 60 minutes, once the surface is dull, the smoothing can be started. The working practices can vary regionally on what the setting profile of the gypsum plaster can be adapted. Solution: The combination of 3 retarders gives the ideal setting curve. 8

ADDITIONAL ADDITIVES FOR THE DRY MORTAR INDUSTRY Accelerators Sigunit as alkali-free setting accelerator for dry shotcrete allows large layer thicknesses in one working step and rapid strength

9 ADDITIONAL ADDITIVES FOR THE DRY MORTAR INDUSTRY Accelerators Sigunit as alkali-free setting accelerator for dry shotcrete allows large layer thicknesses in one working step and rapid strength development. SikaRapid acts as a hardening accelerator and stimulator for cementitious dry mortars. Foaming agents SikaPoro is a combination of anionic and kathionic surfactants to be applied with a foam generator. With Sika foam unit SG 70 a fine, very stable foam is produced, for example for lightweight mortar. Air pores SikaAir Solid are stable, tiny prefabricated air pores with which mortars with high resistance against frost and de-icing agents can be produced. Retarders SikaTard acts as a retarder and set regulator in cementitious dry mortars without loss of strength and can be combined e.g. with SikaRapid. Fibers Sika Fiber improve the stability of the mixture and increase the impact resistance, tensile strength and fire protection. Other additives Sika Silicoll P uncompact is amorphous silica. It increases the strength and microstructure compaction. Thus improves selectively chemical resistance and frost-thaw resistance of cementitious mortars and injection mortars. 9

10 SIKA VISCOCRETE POWDER SELECTION GUIDE All Sika ViscoCrete powders are pure polycarboxylate ether (PCE). They are free of formaldehyde and ammonia and not defoamed. Binder Basis Typical Application Binder Type Sika ViscoCrete 111 P 125 P 150 P 225 P 430 P 510 P 520 P Cementitious Ternary Binder Combination Calcium Sulphate Bound Self-compacting concrete (SCC) Self-levelling underlayment (SLU) Self-levelling screed (SLS) Self-levelling underlayment (SLU) Gypsum boards Gypsum Blocks CEM I R (rapid) CEM I N (normal) CEM II S (furnace slag) CEM II LL (lime stone powder) Ternary binder system ph > Ternary binder system ph < Thermal anhydrite (FDG) Synthetic anhydrite Natural anhydrite Alpha-hemihydrate ph > Alpha-hemihydrate ph < Beta-hemihydrate FDG Beta-hemihydrate natural Performance Sika ViscoCrete 111 P 125 P 150 P 225 P 430 P 510 P 520 P High initial flow ü ü ü ü Long consistency preservation ü ü ü ü ü Fast adsorption (short mixing time) ü ü ü ü ü Little retardation ü ü ü ü ü High early strength ü ü ü Low early shrinkage ü ü ü Low sulphate dependency ü ü ü ü ü Good compatibility with retarders (fruit acids) ü ü ü ü ü A combination of different superplasticizer types can possibly cover your specific application. Please contact our technical service for more information and specific advice. 10

Retardan Powder Selection Guide Retardan P Retardan 704 D Retardan GK Retardan 200 P Retardan 2025 P Chemical Basis Ca-salt of an amino acid modified amino acid Dosage in % of dry weight 0.01-0.02 0.

11 Retardan Powder Selection Guide Retardan P Retardan 704 D Retardan GK Retardan 200 P Retardan 2025 P Chemical Basis Ca-salt of an amino acid modified amino acid Dosage in % of dry weight Application Gypsum boards and structural elements ü ü Building plaster, stucco, plaster filler, machineplaster, hand plaster, adhesive binder, joint fillers ü ü ü ü ü Model and mold gypsum ü ü ü CaSO 4-flowing screed ü ü ü ü Ternary self-levelling underlayment (SLU) ü 11

ALL AROUND COMPETENCE! FROM FOUNDATION TO ROOF.

Corrosion Protection Fire Protection Flatroof Waterproofing

Sealing and Bonding of facades Sika offers for all requirements

Wether by phone, fax, e-mail or in person we are always at your

Through our partnership with the specialized trade, there you can

com Internet: www.sika.de Sika Services AG / 04.

12 ALL AROUND COMPETENCE! FROM FOUNDATION TO ROOF. Floor Coatings Waterproofing Concrete and Mortar Technologie Corrosion Protection Fire Protection Flatroof Waterproofing Sealing and Bonding of interior Concrete Repair and Protection Sealing and Bonding of facades Sika offers for all requirements the right solutions. Wether by phone, fax, or in person we are always at your service. Through our partnership with the specialized trade, there you can also obtain competently advice. Internet: Sika Services AG / Sika Deutschland GmbH Kornwestheimer Straße Stuttgart Telefon Telefax Contact: Business Unit Concrete Peter-Schuhmacher-Straße Leimen Telefon Telefax

Creating Additive Value

Creating Additive Value RHEOLOGY MODIFIERS Non-ionic Polyurethane Associative thickener Medium pseudoplastic rheology profile Less influenced by surfactants TAFIGEL PUR 40 (in butytriglycol/water) 40% active content Low VOC TAFIGEL