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-   -   difference between quartz and quartzitic gravel (http://www.dimcax.com/hust/showthread.php?t=23750)

huangyhg 2009-09-08 06:42 PM

difference between quartz and quartzitic gravel
 
difference between quartz and quartzitic gravel
the aci 224-01 8.3.2 states "typically, some concretes of highly quartzitic gravels have a low strain capacity and a high modulus of elasticity. concretes with a low strain capacity are much more sensitive to shrinkage due to drying (and to a decrease in temperature) and will be subjected to a greater amount of cracking."
however in the same aci 224-01 3.4.2 states "quartz, limestone, dolomite, granite, feldspar, and some basalts can be classified as higher-modulus aggregates, which result in lower shrinkage properties of concrete."
is quartz and quartzitic gravel the same thing? if so, aci is really contradicting themselves
check out our whitepaper library.
quartz is a crystalline mineral while quartzite is a metamorphic rock. both are formed from silica but are otherwise quite different.
ok thanks for the clarification


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