PROFIS ENGINEERING
Band Width Approach – Concrete Breakout Towards the x- Edge
Figure 5.2.1. Band Width Approach for Shear Concrete Breakout Towards the x- Edge
Reference [ 41 ]. Shear load( V ua, x) acts towards the fixed edge in the x- direction. The“ band width” is utilized because no two anchors are aligned to form either a row or a column. The parameter( L x) corresponds to the distance in the direction of V ua, x between the outermost anchors in the anchorage( i. e. distance between anchor 1 and anchor 8). L x is multiplied by a factor of 0.25 to give a“ band width”, which is shown by the purple shading. Anchors spaced in the direction of V ua, x that are within this band width include anchor 1, anchor 4 and anchor 6. These three anchors will be treated as if they were formed in a column( green dashed lines). This“ column” will be defined by the spacings perpendicular to the direction of V ua, x(= L y). ACI 318 Case 3 will be assumed. Anchor 1 is the closest anchor to the x- edge. The distance from anchor 1 to the x-edge is defined by the parameter c a1, x. The area of influence( A Vc, x) for calculating the design concrete breakout strength( ϕV cbg, x) will be defined as shown in the [ 41 ] elevation view.
A Vc, x = 1.5c a1, x + L y + c a2 1.5c a1, x
where L y = s y8-6 + s y7-8 + s y4-7 + s y5-4 + s y3-5 + s y2-3 + s y1-2 such that A Vc, x =( 1.5c a1, x + s y8-6 + s y7-8 + s y4-7 + s y5-4 + s y3-5 + s y2-3 + s y1-2 + c a2)( 1.5c a1, x)
ACI 318 Case 3 provisions apply, such that 1.0V ua, x is assumed to act on the“ column” formed by anchor 1, anchor 4 and anchor 6( i. e. the anchors within the band width 0.25L, x). The design is satisfied if( 1.0V ua, x / ϕV cbg, x) ≤ 1.0.
Band
Width Approach – Concrete Breakout Towards the y- Edge( page 40) will discuss how to consider concrete breakout towards the y- edge for the application illustrated in [ 38 ].
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