Ribeneke:
Cylinder test for uni-axial compression should not experience tension and thus the failure can be shear with compression. Depends on material - i.e. weaker in shear than compression. But, knowing this about a material we can limit the allowable design compression to preclude a shear...
Drew:
Ron just about has it. There is a lot of literature available on this subject that you should be able to locate. Core sampling is the most common, typically 100mm diameter, ideally diameter at least three times the maximum aggregate size, trimmed to 1:1 length:diameter and crushed in a...
Awe:
Non-contact lap requirements apply also to dowels and vertical rebar. In high seismic areas mechanical splices would be required for larger diameter bars. Refer ACI 349-01, 12.14.
In concrete column design, with negligible moments and shears applied i.e. say uniaxial compression, would we check for the maximum shear stress resulting at 45 degress due to the compression? What would be the allowable?
Let me ask this. For a column that has very little externally applied shear or moment, that is in uniaxial compression say, do we check for the maximum (diagonal) shear stress which we would say is about half the compressive stress?