Altro Pol. Additive for increasing strength of cementitious systems Technical and installation data sheet. Typical applications. Product description

Transcription

1 Atro Po Additive for increasing strength of cementitious systems Technica and instaation data sheet November 2016 Product description Atro Po is a compementary part of the Atro fooring package, faciitating subfoor design and repair, in readiness to receive resiient fooring systems or synthetic resin foor finishes. Atro Po is a stabiised styrene butadiene copoymer designed to enhance the physica properties of cement based foor screeds and repair compounds. It contains integra antifoam and antioxidant agents. The incorporation of Atro Po in cementitious compositions imparts greaty improved fexura strength, which together with the high bonding and fast-curing capacity aows the production of thin section seamess foor screeds with exceent durabiity and overa properties. Atro Po is suppied as a white mobie iquid. It is readiy diuted with water and then used to gauge the screed mixture of cement and aggregates to provide the desired performance characteristics. Thickness The minimum recommended design thickness are as foows: 6mm bonded 50mm unbonded 75mm foating Typica appications Faster curing to aow eary overayment Thin section foor screeds Smoothing screeds to even out the surface of damaged or tamped finish concrete Leveing screeds to receive other finishes Screeds of varying thickness to insta fas for drainage purposes Underayments for resiient foor coverings and resin finishes Patching of worn or damaged concrete Advantages Reduced drying time Easy to use singe component, gauged as required Thinner screeds with exceent durabiity and impact resistance Superb adhesion, maintained even in wet conditions Integra antifoam so no additions on site are necessary Sustainabiity Atro s steps to sustainabiity program seeks to optimise our performance with respect to the panet s resources. Pease refer to for further information.

2 Typica physica properties Atro Po strength/cure vaues, guide ony The foowing data is based on aboratory tests against casting and curing cubes in optimum conditions. Site resuts may vary according to working conditions and batch contro of the mixes and thickness. Mix design Performance Day 1 Day 7 Day 28 Atro Po 4 and Atro Po 5 Compressive Strength N/mm Tensie Strength N/mm Fexura Strength N/mm Packaging Atro Po is suppied in 25 and 200 itre containers. Guide coverage The foowing chart shows standard mix references, appication mix drying times and yied etc. Atro Po mix designs Atro Po 4 Appication and use Thickness Substrate Preparation Bonder Mix design Heavy duty foor screed (Resin overayment) Yied 7.5m 12mm 10mm to 25mm Concrete BS 8204, Part 1 or stabe sound substrate Mechanica (to expose cean sound aggregate) Atro Prime standard variant or Atro Proof (wet into wet) Portand Cement: 50kg Sharp washed sand: 70 90kg 3mm to 6mm grano agg: 60 75kg Atro Po (neat) 7 itres Water (cean) to suit Atro Po 5 Appication and use Thickness Substrate Preparation Bonder Mix design Heavy duty thick section foor screed (Resin overayment) Yied 3m 30mm 25mm+ Concrete BS 8204, Part 1 or stabe sound substrate Mechanica (to expose cean sound aggregate) Atro Prime standard variant or Atro Proof (wet into wet) Portand Cement: 50kg Sharp washed sand: 70 90kg 6mm to 10mm Grano agg: 60 75kg Atro Po (neat) 7 itres Water (cean) to suit Coverage rates are dependent on surface profie and porosity. Storage The containers shoud be stored unopened in covered accommodation and protected against frost, direct heat and sunight. For storage temperatures of 5 C to 25 C, the shef ife wi be 12 months in the origina, unopened containers.

3 Substrate requirements and preparation New concrete: The base sab shoud be constructed in accordance with the recommendations of BS 8204: Part 1 and preferaby any fas required shoud be incorporated in the design. Any services shoud be contained within the base concrete and not aowed to intrude into the foor screed. A damp proof membrane shoud be instaed beneath the sab in accordance with the requirements of CP 102. The base concrete shoud be a minimum of C35 grade with a cement content of at east 300 kg/m 2 and be at east 14 days od before the foor screed is to be appied. The concrete SHOULD NOT contain a water-repeent admixture (surface curing membrane). The surface of the base concrete shoud be prepared by mechanica treatment to remove a aitance. Contained shot basting is the preferred method but the extent of treatment shoud be such that the coarse aggregate is ceany exposed in order to provide a good mechanica key. High intensity scabbing is not favoured because it can cause micro cracking to weaken the underying surface. Od concrete: A substrates shoud be ceaned and mechanicay treated as described above to remove any surface contamination such as oi, rubber or faking paint. For surfaces heaviy contaminated with oi or grease deposits, the buk of the contamination shoud first be removed mechanicay. The surface shoud then be thoroughy ceaned by steam ance or with degreasing sovents, foowed by thorough washing with detergent and cean water before wet vacuum ceaning the entire surface. The effectiveness of the ceaning can be assessed by a water spot test. A drop of water from a syringe or eyedropper is appied to the foor from a height of about 10mm. If the drop remains intact and does not spread out or soak into the concrete within a few minutes then adhesion is ikey to be impaired and further foor preparation is necessary. Where it is not possibe to cean the concrete sufficienty to assure adequate adhesion, a mechanica key shoud be formed by anchoring a fine reinforcing mesh over the contaminated surface and appying the Atro Po screed to encapsuate the mesh entirey. The surfaces of precast units shoud be eft as cast and shoud be thoroughy prepared by contained shot basting to remove a adhering dirt and aitance. Mechanica scabbing shoud be avoided since it may we damage the units. After preparation, the surfaces shoud be vacuumed to remove a traces of dirt and dust. The surfaces shoud then be protected against further contamination unti the foor screed is to be aid. Panning Before proceeding with the instaation, carefu consideration shoud determine the best way of instaing the Atro system. Time spent at this stage wi be invauabe towards the success of your instaation. Appication The foowing appication guide is based on aboratory and simuated site conditions. However, when instaations conditions differ appreciaby from those detaied by Atro, the performance characteristics of both mixing and aying may not be as expected. To achieve the best resuts at a times pease endeavour to estabish the correct conditions which in turn wi aow the materias to be aid effectivey, and meet your customer s expectations. Instaation conditions Atro Po can be safey used at ambient temperatures from 5 C to 30 C. However at the higher end of this temperature range, both working ife and open time for troweing wi be greaty reduced and particuar attention wi need to be given to curing to prevent premature drying-out and cracking (do not attempt to ay beow 5 C). Product instaation Priming / bonding Screed thickness (6mm to 30mm): Screeds within this range of thickness shoud be bonded to a prepared substrate using Atro Prime standard two pack epoxy primer or Atro Proof two part surface damp proof membrane. The Atro Po shoud aways be aid into a tacky Atro Prime or tacky second coat of Atro Proof if a DPM is required, refer to the reevant technica and instaation data sheets. Screed thickness (30mm to 50mm): There is an option to use Atro Prime, Atro Proof or Atro Po surry primer. The Atro Po surry primer is prepared by bending together 1 voume of Atro Po to 1 voume of cean water to 3 voumes of fresh Portand cement. The Atro Po shoud be diuted first with water and then the cement sowy added progressivey, whist stirring continuousy using a sow speed eectric dri fitted with a padde bade. The mixed primer shoud be of creamy consistency and it is good practice to pour it through a fine sieve before use to remove any umps of undispersed cement powder. The primer wi have a usabe working ife of at east 2 hours at 20 C. About one or two hours before the foor screed is to be appied, the base shoud first be saturated with cean water and then a excess water removed by squeegee or vacuum. The primer shoud be thoroughy worked into the surface of the dampened concrete base by brush or roer, ensuring that it dispaces a air and wets out the entire surface particuary in the depth of the texture. Care shoud be taken to avoid ponding of the primer. The foor screed needs to be appied before the primer has dried out, so the priming operation must be baanced against the rate at which the foor screed is batched and aid. The rate at which the primer dries out must be assessed on site, since it wi depend on ambient temperature and humidity as we as the porosity of the concrete. If the priming coat has dried out too far it can act as a reease membrane, in which case it shoud be removed or at east heaviy scored to create a mechanica key.

4 Product instaation Remember to aways use the correct PPE. A forced action mixer, such as a rotating pan or trough type, shoud be used. Free fa mixers are not recommended because the mortar tends to ba up and so prevents fu dispersion. For maximum performance the cement and aggregates shoud first be bended dry. A sma proportion of water shoud be added whist continuing to mix foowed by the fu amount of Atro Po. Additiona water shoud then be added progressivey unti the desired workabiity is attained. Pease note: It may not be necessary to add the fu amount of water given in the mix design section depending on the type of materias used. Care needs to be taken to ensure that any dry materia adhering around the sides and base of the mixer is bended fuy into the mix. Normay a mixing time of 2 to 3 minutes shoud ensure a homogeneous mix. Proonged mixing must be avoided since this may cause entrapment of air to the detriment of the finishing characteristics and eventua performance of the screed. The fuy mixed mortar shoud be spread out over the primed surface, preferaby between battens set to the intended thickness, compacted thoroughy, struck off to eve and then the surface cosed with a foat or trowe. Because the poymer quicky skins on the surface, over-troweing must be avoided since this woud disfigure the finish. The troweing must therefore be competed in a singe operation and care must be taken to eiminate a bubbes or open patches on the surface Curing As soon as possibe after troweing and when the screed has hardened sufficienty not to be damaged, the surface must be protected against drying out by pacing poythene sheeting directy onto the screed. Care must be taken to ensure that the sheeting is in compete contact with the screed: otherwise condensation may occur in the air space between, eading to disfigurement of the surface or to banching of the coour if the screed is pigmented. The freshy aid surface shoud be particuary protected against draughts and exposure to direct sunight before the curing medium is appied. Drying A resiient fooring and synthetic resins must be instaed in accordance with their reevant British Standards. These standards state that the reative humidity within the base screed must be beow 75% RH prior to the instaation of the coverings. The addition of Atro Po to a cementitious screed consideraby reduces the drying time of the screed. These times are indicated on the mix design chart overeaf and are dependent upon the screed thickness, the room temperature, the water content of the mix and the eves of air circuation. The times quoted are at C; ower temperatures may require a onger curing period. If the schedue does not aow sufficient time for the thicker designed screeds to dry out, the programme may be acceerated by the appication of Atro Proof surface damp proof membrane to the screed surface as a moisture barrier. Prior to overcoating, the surface preparation of the screed shoud be carried out as per conventiona concrete surfaces. Joints Athough the main foor can be aid seamess, any movement joints in the base sab shoud be carried through the Atro Po screed. On suspended foors a joint shoud be introduced in the screed over support positions to accommodate stresses due to defection. Isoation joints shoud aso be introduced around the perimeter of the foor sab(s) and around coumns, manhoes and other fixtures. A joints shoud be fied with a tough seaant to accommodate movement and provide support to the joint arises. Atro Expand is a purpose-designed seaant for such appications.

5 Protection Whist of an extremey durabe nature these foor systems must be thoroughy protected from the rigours and abuse that exist during the ongoing contractua works. Disposa Due diigence must be adopted if accidenta spiages occur. Recover using absorbent granues, transferring into a suitaby marked container. Disposa of a empty containers and accidenta spiages shoud be in accordance with the oca waste disposa authority. Pease refer to the most up-to-date technica documents, incuding safety data sheets, for the Atro resin variant prior to beginning your instaation. To order E-mai ResinSaesDesk@atro.com Ca Fax NOTE: Atro Ltd ( Atro ) endeavours to ensure that advice and information given in Product Data Sheets, Method Statements and Materia Safety Data Sheets (a known as Product Literature) is accurate and correct. However, where Atro has no contro over the seection of its products for particuar appications, it is important that any prospective customer, user or specifier, satisfies him / hersef that the product is suitabe for the intended appication. In this process, due regard shoud be taken of the nature and composition of the background / base and the ambient conditions both at the time of aying / appying / instaing / curing of the materia and when the competed work is to be brought into use. However, as site conditions and the execution of the work are beyond our contro, we accept no resutant iabiity. Atro s poicy is one of continuous research and deveopment and we reserve the right to update our products and information at any time without prior notice. If you d ike any more information or guidance pease get in touch, we re here to hep. te: fax: emai: enquiries@atro.com or expore