Instructions for use on floors undergoing polishing

Transcription

1 Instructions for use on floors undergoing polishing Surface Prep: 1. Trinic CS Densifier will produce a polish on 3,000 PSI and stronger concrete. 2. Low strength floors may require an application of CS Densifier prior to starting polishing operations. 3. Higher strength floors: Polish the floor to grit prior to the application of Trinic CS Densifier. Application: 1. Dilute CS Densifier 4 to 1 with clean water. 2. Apply CS Densifier with a pump sprayer to saturation; coverage should be 40 m2 (400 sq ft) to 60 m 2 (600 sq ft) per 3.8 L (1 gallon). Puddling is not necessary. 3. Keep the surface moist for 15 minutes. 4. Allow the surface to dry for 1 hour. 5. Proceed with polishing steps. 6. Proceed to sealing. Pop Concrete Supplies & Training offers both water based and solvent based polished concrete sealer depending on the degree of protection required.

2 Instruction for use "No Diamond Polished Concrete" hard troweled floors Surface Prep: 1. Surface must be free from all sealer, paint, waxes, mastics, oil and grease. 2. You may need to open up hard troweled surfaces prior to the application of CS Densifier. The surface must accept the densifier to work grit sanding screens can be used to open up a floor to accept densifier. 4. Clean up sanding residue prior to proceeding. Application: 1. Dilute CS Densifier 4 to 1 with clean water. 2. Apply CS Densifier with a pump sprayer to saturation; coverage should be 400sf to 600sf per gallon. Puddling is not necessary. 3. Keep the surface moist for 15 minutes. 4. Allow the surface to dry for 1 hour. 5. Use a floor buffer with a diamond impregnated pad (800 grit) to remove any residue and bring the floor to a luster. 6. Proceed to sealing. Pop Concrete Supplies & Training offers both water based and solvent based polished concrete sealer depending on the degree of protection required.

3 What densifier works better on what concrete? Very few projects are going to specify a minimum compressive strength of 40 MPa (5,500 PSI) just so the floor can be polished without using a densifier. Some overlay products made do not contain Portland cement. With the increasing use of pozzolans in concrete there is less reactive free lime for conventional densifiers to work with on standard concrete. There are also very weak floors (some almost hard sand like in their density) being rescued by floor polishing. The answer is all densifiers work, some work better than other in different situations. Pozzolans and densifiers do similar things internally verses externally. The majority of products added to mixes or used as densifiers are silica based (or course there are exceptions). Pozzolans have a silica component, Slag is about 40% silica (varies with source), Silica Fume about 95% silica. The smaller the particles are the faster they react, in many cases getting small enough to actually act as accelerators rather than retarding the set. Many polished concrete products are also silica based: it started with sodium silicates, then potassium silicates, now on to lithium silicates and colloidal silica. The first three have a metallic salt component, that s why they can cause efflorescence (less so with Lithium Silicate Trinic LS Lockup) if over applied. Why did this floor white out when the last did not even though I applied the densifier the same way? The answer may have been differing porosity and free lime available in the floors. If your floor is dense (MPa / PSI wise) and has enough free lime to work with, lithium silicates (Trinic LS Lockup) or colloidal silicas (Trinic CS Densifier) generally work fine. If your floor contains very little free lime (was cast with a very high pozzolan dosage) or is weak (MPa / PSI wise), or very young, you may need to look for alternatives or in many cases a combination of alternatives. Trinic CS Densifier is a Colloidal Silica which is pure silica with a particle 100 times finer than silicates and 1,000 times finer than silica fume (which is finer than tobacco smoke), silica fume is 100 times finer than Portland cement which is the rough equivalent size of the grit on 300 grit sand paper you get the point. This is why it reacts quickly when as a surface densifier (it begins to gel almost upon contact). It will also form bonds with silica which is important on floors with little free lime to work with or overlays with no Portland cement. If your floor (or overlay) contains no Portland cement, if your floor was cast with a high percentage of pozzolan (they can use up to 20-50% fly ash), if your floor is young (calcium hydroxide needs time to develop internally), if you ve got a decently hard floor in good shape and you don t want to use diamonds, then Trinic CS Densifier would be a good choice. Trinic CS Densifier has been engineered to contain a range of particle sizes (from 1 nanometer to 100 nanometers) in a specific PH to prevent molding. Trinic s research

4 has found this to be more effective and efficient than typical colloidal silica densifiers which contain a narrow range of particle sizes, its particle packing on a nanoscale. The range of particles fit the pores in a floor like locks in a key allowing the contractor to densify a broad range of floor types. The problem occurs when the key is too small to fit the lock; the colloidal silica can disappear into the concrete without effect to the surface. Many of our customers are using Trinic CLS Densifier a blend of Trinic LS Lockup (a lithium silicate based product) and Trinic CS Densifier (a colloidal silica based product). This is a way to cover all bases. You end up with particle sizes with chemistry to cover most situations. Dense, high strength concrete requires just a little help from surface densifiers to polish compared to problem floors. When concrete is cast with high degrees of excess water, the water evaporates out of the concrete leaving channels behind. The more excess water in the mix, the larger and more frequent the channels and the weaker the mix (less ability to hold the aggregate so the polishing machine can shave it rather than pulling it out). This is the main reason most polishing concrete contractors stay away from the residential market, less quality control with the concrete. You don t know what you re walking into or how much it will cost to get it polished if it will polish at all. You will need to start with the largest particle required to fill the pores and work your way smaller to fill the voids, densify, and provide a uniform plain for polishing. Sometimes this can be accomplished in one densification step; other floors will require more or different densification steps. Very weak porous concrete may require a very large particle in the form of cementitious slurry prior to any attempt at densification. The concrete may be so porous that any densifier will simply absorb into the matrix without benefit to the surface. A neat (no sand or aggregate in the mix) reactive slurry will close the very large voids. This may need to be ground off before going to the next step. The next step would be larger particle (lithium silicate) mixed with smaller particles (colloidal silica). A final step (if needed) would be colloidal silica; this would bond to any silica particles present and fill any microscopic low spots readying the concrete for finale polishing. Obviously product and machine usage will be much higher than polishing dense concrete often making this option more expensive than coating the floor with a film type product.

5 Evaluating floors: There are ways to evaluate a floor for polishing before quoting it. You will need to develop benchmarks (test floors you re currently polishing) before you can accurately predict how a future floor will polish and what densifier to use on the floor. The first tool I would recommend every polishing contractor obtain is a Schmidt Hammer also known as a Swiss Hammer. It s a simple non-destructive test device that will give you instant data about concrete strength and thus polishability. Once you gain an understanding of the correlation between PSI and polishability you can gain a sense of how (or if) a floor will polish and to some extent material costs to polish; Low MPa / PSI floor = more densifier required, high MPa / PSI floor = more diamond usage especially if aggregate exposure is required. Another simple test you can perform is an acid resistance test. The higher the pozzolan load in the floor the lower the amount of free lime available, the more acid resistant the concrete will be. Acid staining contractors quickly develop a feel for how different floors take acid stain, due in part to differing free lime content, polishing contractors can evaluate free lime in a similar way. You ll have to develop benchmarks for acid resistance. This will help guide your choice of densifiers or a blend of densifiers; the denser and more acid resistant the concrete is the more I d be inclined to lean towards colloidal silica vs. a lithium silicate, if the acid foams green on contact you know you ve got plenty of free lime for lithium silicates to work with. This test will also reveal any polymer concrete or Portland cement free concrete you may encounter.