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Integral damp proofing in concrete involves adding materials to the concrete mix to make the concrete itself impermeable. [ 4 ] Surface suppressant coating with thin water proof materials such as epoxy resin for resistance to non-pressurized moisture such as rain water or a coating of cement sprayed on such as shotcrete which can resist water ...
For example, pharmaceuticals that pick up more than 5% by mass, between 40 and 90% relative humidity at 25 °C, are described as hygroscopic, while materials that pick up less than 1%, under the same conditions are regarded as non-hygroscopic. [32] The amount of moisture held by hygroscopic materials is usually proportional to the relative ...
Rising damp from the ground may be prevented by most simple means. Six inches of good Portland cement concrete should cover the whole site of the dwelling, and concrete never less than nine inches thick should underlie all walls. A damp course should disconnect the whole of the foundations from the superstructure.
In fresh concrete, air entrainment improves workability and makes it easier to handle and pump. It also helps prevent bleeding and segregation, unwanted processes that can occur during mixing. In hardened concrete, air entrainment strengthens the material by making it better able to withstand freeze-thaw cycles.
The Hygroscopic Cycle is a concept that has evolved recently and is at the heart of intensive research on hygroscopic fluids. Recent developments have been the Kalina cycle , [ 17 ] but with the actual configuration, it is expected to have an impact in locations with poor access to water, and a good integration with combined cycle plants, and ...
Materials such as stones, sand and ceramics are considered 'dry' and have much lower equilibrium moisture content than organic material like wood and leather. [7] typically a fraction of a percent by weight when in equilibrium of air of Relative humidity 10% to 90%. This affects the rate that buildings need to dry out after construction ...
Hempcrete is a construction building material that uses hemp shives, aggregate, water, and a type of binder to act as non-bearing walls, insulators, finishing plasters, and blocks. The material has low mechanical properties and low thermal conductivity, making it ideal for insulation material.
The mechanism of ASR causing the deterioration of concrete can thus be described in four steps as follows: The very basic solution (NaOH / KOH) attacks the siliceous aggregates (silicic acid dissolution at high pH), converting the poorly crystallised or amorphous silica to a soluble but very viscous alkali silicate gel (N-S-H, K-S-H).