PROFIS ENGINEERING
Conservative assumption
• Only consider concrete breakout with respect to Case 3 for col 1.
•( 1.0V ua / ϕV cbg, col 1) controls for concrete breakout in shear.
Alternate assumption
• Consider Case 1 / Case 2 for col 1 and col 3.
• Check( 0.5V ua / ϕV cbg, col 1) for column 1
• Check( 1.0V ua / ϕV cbg, col 3) for column 3
• MAX {( 0.5V ua / ϕV cbg, col 1);( 1.0V ua / ϕV cbg, col 3)} controls for concrete breakout in shear.
Unequal
Number of Anchors and Equal Spacing
Figure 4.2.
Reference Figure 4.2 [ 12 ]. It illustrates a hypothetical anchorage consisting of ten anchors, which are installed around the perimeter of the plate. The shear load( V ua) acts towards the y- edge, so shear concrete breakout will be calculated with respect to the potential failure surface that can develop from any row being considered. Considering the anchor layout with respect to rows: row 1 and row 4 each consist of three anchors, while row 2 and row 3 each consist of two anchors. Assume V ua acts on all four rows.
For rows 1 and 4, s x12 < 3c a1, row 1 and s x23 < 3c a1, row 1 will be assumed; therefore, the anchors in these rows act as a group. For rows 2 and 3,( s x12 + s x23) < 3c a1, row 1 will be assumed, so the anchors in these rows will likewise act as a group. Therefore, the anchors in each of the four rows act as a group with respect shear concrete breakout calculations( e. g. reference ACI 318-19 Section 17.5.1.3.1).
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