Floors are particularly prone to contamination because they are horizontal surfaces and act as the obvious catchment area for spillage of liquids or anything which falls and settles. Even on a new construction, splashes of paint, oils, plaster and mortar are common; not to mention dirt from foot traffic during the operation plus residues of curing compound used during construction. On existing floors, oil and dirt are common in production areas and other materials may have penetrated the concrete surface over long period of time.
New concrete floors:
A first-class, well finished and well cured concrete floor slab may need little preparation other than sweeping or, preferably vacuum cleaning. The use of an industrial vacuum cleaner is always the first choice if is available – as it removes the dust progressively, unlike sweeping which always deposits some dust on previously swept areas.
The most likely problems, if they occur, are surface laitance , plaster for mortar splashes and residues of applied curing compounds. The common choise for surface preparation in these cases is between acid etching and sweep blasting.
Acid etching:
Is effective in removing only light laitance and will remove both plaster and mortar stains by local application.
Remember, it does require protective clothing and thorough hosing down with fresh water to neutralize the acid. This means a soaking wet floor and long drying out period before any further treatment can be applied. Extra water in the building may not be desirable in some cases. Also, acid etching vacuumed when dry. The total financial effect of these procedures is to increase the coast of this treatment almost to the levels of mechanical cleaning methods.
Wire brushing:
Should never be contemplated, except to deal with very small local patches of plaster or mortar.
ليست هناك تعليقات:
إرسال تعليق