PROFIS ENGINEERING
Shear Load Parallel to the x- Edge
Figure 4.5.1.
Reference Figure 4.5.1 [ 31 ]. It shows the parameters that will be considered with respect to concrete breakout failure parallel to the x- edge. ACI 318 provisions for shear load acting parallel to the edge assume the load acts towards the edge, but the calculated concrete breakout strength is doubled. For this example, the shear load V ua will be assumed to act towards the x- edge and concrete breakout failure surfaces will be assumed to develop from col 1 and col 2. Based on the x- edge distance and spacing between col 1 and col 2, ACI 318 provisions could be extrapolated as shown below.
Consider Case 1 / Case 2
• The x- edge distance( c a1, col 1) equals 4 in.
• The spacing( s x12) between col 1 and col 2( 6 in) is greater than c a1, col 1
• A complete failure surface can develop from col 1 and col 2.
• Case 1 / Case 2 applies for the interaction between col 1 and col 2.
• V ua is assumed to act towards the x- edge, and to be distributed proportionately between col 1 and col 2.
• V cbg, col1 = A vc, col1 ψ
A ec, V ψ ed, V ψ c, V ψ h, V ψ parallel, V V b where ψ parallel, V = 2.0 vc0
• A Vc, col 1 =( 1.5c a1, col 1 + s y34 + s y23 + s y12 + 1.5c a1, col 1)( 1.5c a1, col 1)
• Check V ua, x, col 1 / ϕ( V cbg, col 1) ≤ 1.0 where V ua, x, col 1 = 0.50V ua
• V cbg, col2 = A vc, col2 ψ
A ec, V ψ ed, V ψ c, V ψ h, V ψ parallel, V V b where ψ parallel, V = 2.0 vc0
• A Vc, col 2 =( 1.5c a1, col 2 + s y34 + s y23 + s y12 + 1.5c a1, col 2)( 1.5c a1, col 2)
• Check V ua, x, col 2 / ϕ( V cbg, col 2) ≤ 1.0 where V ua, x, col 2 = 1.0V ua
• MAX {( 0.5V ua / ϕ( V cbg, col 1);( 1.0V ua / ϕ( V cbg, col 2)} controls with respect to shear concrete breakout towards the x- edge.
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