Patches concrete

In addition, concrete patches filled in later would have flown out of these holes like corks out of a shaken champagne bottle during an explosion, thus making the holes just as visible as they were before. On closer inspection, Prof, van Pelts allegation turns out to be not only demonstrably wrong, but utterly absurd. 

Americau Associatou of State Highway Trausportation Officials, Laboratory evaluations of rapid set concrete patching materials. Report 99 NTPEP 160, Washington, DC, 2000. 

Reshveld . [H.B. FuUer] Epoxy for adhesive, sealant concrete patching qrplics. 

Uses Accelerator for amine- or mercaptan-cured epoxies and PL) foam systems for adhesives, concrete patching compds., elec, potting/encap-sulation, coatings, laminates, low-color castings Features Lt. color, low odor, formaldehyde-free Properties Straw clear liq. dens. 8.0 Ib/gal vise. 3-3.5 poise amine no. 

Castor oil glycidyl ether epoxies, flexibilizing concrete patching compounds... 

Filler treatment in filled polyester or epoxy coatings (epoxy concrete patching formulations). 

Pike, R. G., and Baker, W. M., Concrete Patching Materials, Federal Highway Admin. Report, FHWA-RD-74-55 (April 1974)... 

In contrast to other polymers the resistance to water permeation is low due to the hydrolysis of the poly(vinyl acetate) (163,164). Ethylene copolymers have been developed which have improved water resistance and waterproofness. The polymer can be used in the latex form or in a spray-dried form which can be preblended in with the cement (qv) in the proper proportion. The compressive and tensile strength of concrete is improved by addition of PVAc emulsions to the water before mixing. A polymer-soHds-to-total-soHds ratio of ca 10 90 is best. The emulsions also aid adhesion between new and old concrete when patching or resurfacing. 

Chlorinated rubber floor paints are probably the most common of the lower-cost floor paints on the market. They produce tough and chemically resistant coatings, but their adhesion to concrete is not always good. They tend to wear off in patches and cannot be considered as a durable floor treatment except under light traffic conditions. However, re-coating is a simple job and floors can easily be repainted over weekend shutdowns, for example. Similar paints based on other resins such as acrylics, vinyls and styrene butadiene are also used. 

These are used to produce prepackaged products such as decorative wall coatings, ceramic tile adhesives, selfleveling floor overlays and patching mortars for concrete structures. On site, addition of the product manufacturers specified amount of water produces a material with the... 

Latex-modified mortars and concretes have become promising materials for preventing chloride-induced corrosion and for repairing damaged reinforced concrete structures. In Japan and the USA, latex-modified mortar is widely used as a construction material in bridge deck overlays and patching compounds, and for finishing and repairs [99]. Polymer-cement hydrate-... 

In a study of 1,752 patients considered to have occupational dermatoses, contact dermatitis was the main diagnosis in 1,496 patients (92% women, 83% men). The allergic type, as opposed to the irritant type, was more prevalent in men (73%) than in women (51%). Positive patch tests to chromium (not otherwise specified) occurred in 8% of the women and 29% of the men. Among 280 chromium-sensitized men, 50% were employed in building and concrete work, 17% in metal work, and 12% in tanneries. In the 42 chromium-sensitized women, 20% were in cement work, 19% in metal work, 28% in cleaning, and 15% in laboratory work (Fregert 1975). 

For applying new concrete over old concrete, such as in the case of a patch, epoxy is often the best solution as an alternative for the new concrete. In these formulations an epoxy... 

Fig. 12.3 SEM (backscattcred electron image) of a concrete showing gel (dark patches) formed by ASR, present in the cement paste in places far removed from the reactive aggregate. Bright regions are of unhydrated clinker. Courtesy WHD Microanalysis Consultants Ltd, Ipswich, UK (H64).

Epoxy seal coating was first applied as test patches in industrial plants in 1953. In 1957 epoxy polymer concrete was first used as a wearing course in the repair of popouts and spalled areas on the surfaces of various bridge decks in California (ACI, 1993). 

Acrylic polymer concrete and mortars fast curing good chemical properties patch repairs... 

As a concrete repair and as patching mortars they are used to ... 

Structural and semistructural adhesives for steel and aluminium, crack repair adhesives for concrete and as patch-repair compounds and grouting compounds (Morton International, 1988 Rees et al., 1994). 

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