Polished concrete, discovered about 14years ago and has taken its path to history as a sustainable andlow-maintenance paving option in almost all market segments.
We have all walkedon a polished concrete surface in recent years. It is such a popular andfast-growing sector that, in many cases, is outperforming consumers andcontractors with new technologies and new methods. This rapid growth has putthe industry in a very volatile state, leaving consumers confused about what isand what is not polished and what aspects of performance to expect. (Burns, 2015)The Concrete Polishing Association of America (CPAA) was formed inNovember 2009 to create standards for concrete processing with a glossy finishand help define these processes so that architects, designers and consumers canbetter understand the selection process. CPAA’s leadership consists of manufacturersand contractors to provide continuity in the creation of these standards andprocedures. The CPAA defined polished concrete as;”The act of changing a concrete floor surface, with or without additionalexposure, to achieve the desired level of glossy finish”. There are threetypes of polished concrete according to the CPAA.
They are abrasive polishesbonded to concrete, burnished polished concrete and topically polishedconcrete. The”polishing process” can divided into three sections. Those are grinding,densifying and polishing.
(wine, n.d.)There are many flooring systems in themarket and big competition also there. So, evaluation and made modificationshould need to polished concrete for survive in industry. 2.
1 Grinding Whenconsidering floor restoration, that not all types of flooring will be similarto glass. Concrete grinding occurs before the polishing process, making it asimpler option and one that takes less time when ultra-bright surfaces are notrequired. The resulting grinding texture is a gritty abrasive that is halfwaybetween an opaque appearance and a low-level gloss, a classic appearance ofsteps or exterior surfaces.The rectified cement can also besealed with a urethane sealant to achieve a finish similar to cement smoothedin fewer steps. In fact, a floor sealed with urethane can work better in manyenvironments than a polished floor.
Since concrete processing is aseries of steps, the level of resistance, durability and brightness improves asmuch as you cut and remodels the concrete. This is the reason why the groundcement is not as bright as its polished counterparts; polishing requires asignificantly higher production. Both, however, offer a professional look, sothe type of concrete we choose depends entirely on our preferences. (O’Shannessy, 2015) Figure 2 – Grinding Steps different exposes of Aggregate (polished-concrete-the-complete-guide-2017, n.d.) · LightSand / Cream FinishThe impactof light sand is a polished, polished surface that, as a rule, expands sandparticles onto the concrete floor.
This finish is considered a”creamy-looking” surface and is the most popular choice for polishedfloors and architectural floors.· Salt & Pepper FinishThe presenceof salt and pepper is a smooth and polished surface, which usually exposes afine-grained spray to the concrete floor. This finish is chosen more often togive the appearance of the old surface. The cutting depth of the surface is1/16 inches.· Medium Aggregate FinishThe averageexposure of the population as a whole ensures the greatest amount of theaverage aggregate in a concrete floor with a low or no aggregate impact inrandom places. Approximate cutting depth of the surface is 1/8 of an inch.· Large Aggregate FinishLarge aggregate exposure is a more “cut” surface, which usually exposes the largest amount of the largest aggregate in the concrete floor. Finishing is preferable when the substrate has been planted using tuned aggregates.
On some floors, including the restoration of the old concrete, there may be limitations in the depth of cut of the floor. The cutting depth is 1/4 inch.(polished-concrete-the-complete-guide-2017, n.d.)2.2Horning Burnishingbegins with a 50-grain resin pad, which is quite aggressive and can be used toexpose the small aggregate slightly.
The scratches and grooves were left with a50-grain resin pad.Sandingrefers to smoothing and removing scratches and generally involves the use of50, 100 and 200 grain discs.A glossysurface with a 200-gram pad is smooth, scratch-free and totally opaque orglossy. There may be vortexes on the surface, but there are no deep scratches.The injection usually takes place after the passage of 200 grains: a 200 gritis not aggressive enough to cut into the concrete and open more holes, but a200 grit is aggressive enough to cut the hardened mortar.One aspectof salt and pepper refers only to the exposed grains of sand. Often, this aspectcan be achieved by removing the cement cream with a 200-grained buffer in onestep, exposing the cement paste matrix. 2.
3 Densifiers TheDensifiers are used to harden the concrete substrate. This is useful in severalaspects. First of all the hard cement is easier to polish and made a glossyfinish. Secondly, a harder concrete substrate works better as a flooringoption. The densifiers are complicated to understand but relatively easy touse.
The densifiers normally consist of lithium, sodium silicate or potassium.The sodium portion, lithium of the chemical composition is used to transfer thesilicate to the concrete. When the silicate meets calcium hydroxide, which iscommonly known as free lime, located within the concrete substrate, ittransforms and creates a crystalline structure. This crystalline structurehelps to add resistance and abrasion resistance to the concrete surface.
When the seal is addedto the concrete during polishing, it is better dictated by the concrete itself.If the concrete is soft and porous, the use of significantly thickeners duringthe process would be very useful. This would help the polishing technicianachieve maximum refinement with diamond tools. However, if the concretesubstrate has a high structural strength, it has been finished on a hard anddense surface, so a small additional densifier would have been required. Most densifiersreact with cement in the same way creating a harder and dense surface. (Harris., n.
d.)2.4PolishingConcreteprocessing consists of several steps, but grindding and polishing are the bestknown. “Polishing”, but “polishing is a separate task”separate from grinding. If you are brilliant, you will have to work on severalsteps to achieve it.The highestlevel of cement, the glossy appearance is strong, durable and full of clarity.
It has a reflective appearance and a high-end look. 2.4 Gloss LevelDepending onthe diamond sand used to polish a concrete floor, various levels of gloss canbe achieved. You can expect to reach the level.· Level 1 (Flat / Ground)In general,you can achieve a level 1 floor sanding by stopping under the 100-grain bond:when you look directly at the ground, it will look a little foggy with littleor no clarity or reflection.· Level2 (Satin / Honed)A level 2polished enamel is obtained by stopping at 400 resinous bonds, producing aglossy finish.
When you look directly at the finished floor and at about 100feet, you can begin to see a slight reflection on your head. This grain levelproduces a low gloss matt finish.· Level3 (Semi-polished)A level 3sanding is achieved by switching to an 800-grit abrasive or higher. The surfacewill have a much higher brightness than the level 2 finish, and you’ll start tosee good light reflectivity. At a distance of 30 to 50 feet, the floor willclearly reflect lateral and top lighting.· Level4 (Highly Polished)This levelof brightness produces a high degree of brightness, so that when you placeyourself directly on the surface, you can see your reflection with totalclarity.
Furthermore, the terrain seems to be wet when viewed from differentstrategic points. A level 4 sanding is achieved by switching to a 3,000-grainedadhesion resin diamond or by polishing the floor with a high-speed burnerequipped with special polishing pads. (polished-concrete-the-complete-guide-2017, n.d.) 2.5 ColouringFigure 4 – Different coloring choices (polished-concrete-the-complete-guide-2017, n.
d.) · integral –considered environmentally friendly and performed at the time· Integralby sowing a cement / pigment mixture in the upper part during power trowel finishing· Penetrating Water Based Dyes – Madeduring the polishing process and considered environmentally friendly.· Penetrating Solvent Based Dyes – Made during the polishing process and is not considered environmentallyfriendly.· Penetrating Acid Stain – Made during the polishing process and is not considered environmentally friendly.· Penetratingcolor surface sealants that also form a film and produce a firmer color.Considered ecological.
(polished-concrete-the-complete-guide-2017, n.d.) 2.6 Comparison 3 ConclusionIn flooring, modern world areexpecting rapid constructing, less time consuming and more economical,aesthetic and less maintaining systems. Because all are in very busy life. Also,there are big competition in flooring industry. So, it is necessary to do acomparative on concrete polishing and traditional flooring systems. The research is to be carried out toovercome the problems mentioned in above.
So as a new emerge to the flooringindustry people should identify what are the defects and what are the benefitsof this. Then considering more facts, we can take a conclusion of concrete flooringis more suitable for the industry or not. 4 AcknowledgementThe authors is grateful to the research supervisorDr.
Lesly Ekanayake for the guidance and to the colleagues for the help.