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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 ...
ASTM C1293: "Test Method for Concrete Aggregates by Determination of Length Change of Concrete Due to Alkali-Silica Reaction". It is a long-term confirmation test (1 or 2 years) at 38 °C in a water-saturated moist atmosphere (inside a thermostated oven) with concrete prisms containing the aggregates to be characterised mixed with a high-alkali ...
The relationship between water content and equilibrium relative humidity of a material can be displayed graphically by a curve, the so-called moisture sorption isotherm. For each humidity value, a sorption isotherm indicates the corresponding water content value at a given temperature. If the composition or quality of the material changes, then ...
In this technique, a sample of material is weighed, heated in an oven for an appropriate period, cooled in the dry atmosphere of a desiccator, and then reweighed. If the volatile content of the solid is primarily water, the loss on drying technique gives a good measure of moisture content. [ 5 ]
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 ...
Other materials are also used to make a superabsorbent polymer, such as polyacrylamide copolymer, ethylene maleic anhydride copolymer, cross-linked carboxymethylcellulose, polyvinyl alcohol copolymers, cross-linked polyethylene oxide, and starch grafted copolymer of polyacrylonitrile to name a few. The latter is one of the oldest SAP forms created.
Evaluate the quality and homogeneity of concrete materials; Predict the strength of concrete [7] [8] Evaluate dynamic modulus of elasticity of concrete, Estimate the depth of cracks in concrete. Detect internal flaws, cracks, honeycombing, and poor patches. The test can also be used to evaluate the effectiveness of crack repair. [9]
A less dense, and hence lighter material means that HPFRCCs could eventually require much less energy to produce and handle, deeming them a more economical building material. Because of HPFRCCs’ lightweight composition and ability to strain harden, it has been proposed that they could eventually become a more durable and efficient alternative ...