huangyhg

astm c42
can anybody tell me the specifications for core drilling a 4" slab for testing.
diameter, etc.
pray like everything depends on god
work like everything depends on you.
astm c 42
some points to note for 4 inch slab.
1. use pachometer to avoid rebar
2. length to diameter ratio of between 1.9 to 1 and 2.1 to 1 is preferable. correction values for l/d ratios between 1.00 to 1.75 are provided in c42 and in link below in item 5. values same as c 42 values
3. nominal core diameter greater than or equal to 3 x msa
4. at least 3.75 inch diameter core is preferable...smaller diameters may yield unreliable results. for this diameter, length of core before capping must be at least 0.95 x 3.75 = 3.56 inches. after preparation of ends of core you might not get that with core from 4 inch sog. you may have to use smaller core.
5. found link below on net. similar to astm c42. moisture conditioning in sect 7.3 seems slightly different to c 42 sec 7.3 provisions.
thanks!!!
pray like everything depends on god
work like everything depends on you.

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