Brick durability

A stucco of lime mortar will protect the sides. Mud can also be made into unfired bricks for "lump-wall" construction, but unless you have a suitable clay-containing soil, lime or cement must be added to make the bricks durable. 

The absorption value of the burnt brick is a function of the calcium carbonate content in the raw material (within the normal brick-firing temperature range). This can be determined by thermal analysis. The different forming techniques alter this relationship. The saturation coefficient (standard CAN3 -A82.2-7 8) seems to be proportional to the amount of fine particles. It is emphasized that both absorption and saturation coefficients should be used in evaluating brick durability. 

Kung, J. H., Frost Durability Study on Canadian Clay Bricks III. Characterization of Raw Materials and Burnt Bricks, Durability of Bldg. Mater., 5 125-143 (1987)... 

Pa.ints, Paints (qv) prepared from poly(vinyl acetate) and its copolymers form flexible, durable films with good adhesion to clean surfaces, including wood, plaster, concrete, stone, brick, cinder blocks, asbestos board, asphalt, tar paper, wahboards, aluminum, and galvani2ed iron (147). Adherence is also good on painted surfaces if the surfaces are free from dirt, grease, and mst. Developments in emulsion polymeri2ation for paint latices have been reviewed (148). 

Hydraulic limes (84) may be used for mortar, stucco, or the scratch coat for plaster. They harden slowly under water, whereas high calcium limes, after slaking with water, harden in air to form the carbonate but not under water at ordinary temperatures. However, at elevated temperatures achieved with steam curing, lime—silica sand mixtures do react to produce durable products such as sand—lime bricks. 

Other applications of ceramics require clay, either raw or purified, sand, and feldspar. Brick, porcelain, and white wares are made from these raw materials the main expenditure in making these products is in firing the mixtures of powders to a dense solid. Ordinary brick made from fire-clay requires a small amount of energy even refractory brick for high temperatures and chemical durability, made partly from purified oxides such as alumina or chrome ore,... 

Obviously, durability is greatly enhanced by specifying stainless rather than mild steel, engineering rather than common bricks, etc. Comparative life expectancies of materials are tabulated in reference books such as that published by NBA Construction Consultants Limited in 1985. 

Sulfur Coatings (1J>, 18). Molten sulfur, often mixed with fibers or modifiers can be used to spray coatings on unbonded block or brick buildings, linings for ponds, portland cement concrete, and other applications where a durable coating is required or useful. 

What do bamboo stalks, mud bricks, steel-belted radial tires, fiberglass fishing rods, reinforced concrete, and the heat tiles on a space shuttle have in common The answer is that these materials are all composites. A composite is a material consisting of two or more components with overall properties different from and superior to either or any one of the individual components. For example, many pleasure boats today have hulls made of a composite material called reinforced plastic that contains glass, plastic, carbon, or some other type of fiber embedded in plastic. The composite material is stronger, more durable, and less dense than the fibers or plastics of which it is made. 

As a result of thermal stresses, the fireproof brick of a cremation oven inevitably wears out, and eventually this becomes a serious hazard. In the civilian cremation ovens which had been constructed in the usual manner and with the building materials normally used in the 1930s, the lifespan of the fireproof brick was about 2,000 cremations, but the Topf firm had managed to extend its durability to... 

In sulfuric acid production, acid brick lining of membrane coated mild steel tanks and reaction vessels is considered the most durable and versatile construction material for the sulfuric acid plant. Such linings wiil reduce the steel shell temperature and prevent erosion of the normally protective iron sulfate film that forms in stagnant, concentrated (oxidizing) sulfuric acid. Dilute (red uC ing) sulfuric acid solutions are very corrosive to carbon steel, which must be protected by impermeable (e.g., elastomeric) membranes and acid brick lining systems. Such acid brick linings often employ membranes comprising a thin film of Teflon or Kynar sandwiched between layers of asphalt mastic. 

The brick and mortar used in many construction appiications invoives chemicai reactions with caicium and other substances. Although these materials have been used for centuries, chemistry continues to improve their durability and performance. 

The cheapest and least durable chimney is the guyed steel stack. Self-supporting metal stacks and those of reinforced concrete come next. Radial and hollow brick stacks, properly designed, are cheaper than those of common brick of equal excellence. 

Mortar (sometimes called cement) is used to bond surfaces like bricks together, but also for plastering walls. Historically, it has been composed variously of lime, sand, clay, volcanic rock and ash, brick dust, and potsherds. Early lime mortars that set simply by reaction between the lime and carbon dioxide in the air offered little protection from deleterious effects of water to the structure. Aggregate mortars that incorporatepozzolans and silicates, which react to bond with calcium, do not need C02, and some can even set underwater. These are called hydraulic mortars, and offer durability in weather, but are less suitable for situations where plasticity is needed, as in restoration projects, for example. 

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