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Michigan Concrete Association recommends a regular salt like Morton table salt instead of an ice melter because it’s 100 percent sodium chloride (NaCl). This, however, is recommended for ...
When atmospheric carbon dioxide (CO 2), or carbonate ions (HCO − 3, CO 2− 3 dissolved in water) diffuse into concrete from its external surface, they react with calcium hydroxide (portlandite, Ca(OH) 2) and the pH of the concrete pore water progressively decreases from 13.5 – 12.5 to 8.5 (pH of water in equilibrium with calcite).
Water intrusion into the indoor environment can be attributed from causes other than rising damp. Moisture penetration has been an ongoing problem for residences as evaporation occurs at the edge of the damp area, resulting in "tide marks" due to salt deposition. [30] The "tide mark" is commonly distinguished as a feature of rising damp.
Weathering carbonation occurs in concrete when calcium compounds react with carbon dioxide (CO 2) from the atmosphere and water (H 2 O) in the concrete pores. The reaction is as follows. First, through chemical weathering, CO 2 reacts with water in the concrete pores to form carbonic acid: CO 2 + H 2 O ⇌ H 2 CO 3
A fairly well-defined reaction front can often be observed in thin sections; ahead of the front the concrete is normal, or near normal. Behind the reaction front, the composition and the microstructure of concrete are modified. These changes may vary in type or severity but commonly include: Extensive cracking; Expansion
To convert the oxide notation in LDH formula, the mass balance in the system has to respect the principle of the conservation of matter. Oxide ions (O 2−) and water are transformed into 2 hydroxide anions (OH −) according to the acid-base reaction between H 2 O and O 2− (a strong base) as typically exemplified by the quicklime slaking ...
The water diffusion time is thus proportional to the square of its transport distance. As a consequence, the water saturation degree inside thick concrete structures often remains higher than 80%, a level sufficient to provide enough water to the system and to maintain the alkali-silica reaction on going.
The water will slowly seep into the ground and make its way into soil. It’s recommended to use the soaker hose method at least three times a week for around 15 to 20 minutes each time.