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 Soft Metric Bar Sizes vs. Inch-Pound Bar Sizes Bar Size Designation Soft Metric  Inch-Pound #10 #3 #13 #4 #16 #5 #19 #6 #22 #7 #25 #8 #29 #9 #32 #10 #36 #11 #43 #14 #57 #18

  EC2 6.4.2 Load distribution and basic control perimeter (3) For loaded areas situated near openings, if the shortest distance between the perimeter of the loaded area and the edge of the opening does not exceed 6d, that part of the control perimeter contained between two tangents drawn to the outline of the opening from the centre of the loaded area is considered to be ineffective (see Figure 6.14). (4) For a loaded area situated near an edge or a corner, the control perimeter should be taken as shown in Figure 6.15, if this gives a perimeter (excluding the unsupported edges)  smaller than that obtained from (1) and (2) above. (6) The control section is that which follows the control perimeter and extends over the effective depth d. For slabs of constant depth, the control section is perpendicular to the middle plane of the slab. For slabs or footings of variable depth other than step footings, the effective depth may be assumed to be the depth at the perimeter of the loaded area as