One hectare comprises between 1.2 and 1.6 football pitches, as soccer fields are known in British English. An internationally-sanctioned soccer field is 100 to 110 meters in length by 64 to 75 meters in width, comprising between 0.62 and 0.82 hectares depending on the field. Keep Learning.
From Wikipedia, the free encyclopedia. Alkaliâaggregate reaction is a term mainly referring to a reaction which occurs over time in concrete between the highly alkaline cement paste and non-crystalline silicon dioxide, which is found in many common aggregates.he alkaliâaggregate reaction is a general, but relatively vague, expression which can lead to confusion. More precise definitions include the following: 1  Alkaliâsilica reaction (ASR, the most common reaction of this type); 2  Alkaliâsilicate reaction, and; 3  Alkaliâcarbonate reaction.
Alkali-silica reaction (ASR) can cause serious expansion and cracking in concrete, resulting in major structural problems and sometimes necessitating demolition. This is a short introduction to ASR-for more information, see the Understanding Cement book/ebook.dentification of alkali-silica reaction. Gel may be present in cracks and within aggregate particles. The best technique for the identification of ASR is the examination of concrete in thin section, using a petrographic microscope.