Product Technical Guides : US-EN Cast-In Anchor Channel Fastening Technical Guide | Page 48

1. Anchor Channel Systems 2. HAC Portfolio 3. HAC Applications 4. Design Introduction 5. Base material 6. Loading 7. Anchor Channel Design Code 8. Reinforcing Bar Anchorage 9. Special Anchor Channel Design 10. Design Software 11. Best Practices 12. Instructions for Use Table 2.2.2.2 and figure 2.2.2.3 provide information about the minimum corner distance for pair of HAC. See chapter 9, Anchor Channel Design for additional design information. 2.2.3 HAC IN TOP AND BOTTOM OF SLAB CORNERS Single HAC in face of slab corners Table 2.2.2.2 — M  inimum substrate edge and corner distances for pair of HAC in corners in normal weight, sand-lightweight and all light-weight concrete Single HAC in top of slab corner Minimum c ca2 HAC-40 In (mm) *1.97 (50) 3.70 (94.00) HAC-50 In (mm) *1.97 (50) 4.31 (109.50) HAC-60 In (mm) 2.95 (75) 6.01 (152.50) HAC-70 In (mm) 2.95 (75) 7.09 (180.00) *For all-lightweight concrete, c a1 = 2.95” (75 mm) Table 2.2.3.1 — M  inimum substrate edge and corner distances for single HAC in a corner in normal weight, sand-lightweight and All light-weight concrete Minimum c a2 Anchor channel Units Minimum c a1 Minimum c a2 HAC-40 In (mm) *1.97 (50) *1.97 (50) HAC-40 In (mm) *1.97 (50) *1.97 (50) HAC-50 In (mm) *1.97 (50) *1.97 (50) HAC-50 In (mm) *1.97 (50) *1.97 (50) HAC-60 In (mm) 2.95 (75) 2.95 (75) HAC-60 In (mm) 2.95 (75) 2.95 (75) HAC-70 In (mm) 2.95 (75) 2.95 (75) HAC-70 In (mm) 2.95 (75) 2.95 (75) *For all-lightweight concrete, c a1 and c a2 = 2.95” (75 mm) Minimum c a1 Units Anchor channel Minimum c a1 Units Figure 2.2.3.2 illustrates a pair of HAC in a corner. Corner distances greater than the minimum corner distance may be required based on the structural adequacy of the concrete at the corner. Table 2.2.2.1 — M  inimum substrate edge and corner distances for single HAC in a corner in normal weight, sand-lightweight and all light-weight concrete Anchor channel AC232 provides design guidelines to account for the influence of corners where only one anchor channel is present. The design of this type of application is covered in ESR-3520. Table 2.2.3.1 provides the minimum edge and corner distances for HAC. HAC requirements for top and bottom of slab corners are equal. corner configuration where the anchor channels are installed perpendicular to each other; see Figure 2.2.3.2. AC232 provides design guidelines to account for the influence of corners where only one anchor channel is present. The design of this type of applications is covered in ESR-3520. Table 2.2.2.1 provides the minimum edge and corner distances for HAC. 14. Design Example 2.2.2 H  AC IN FACE OF SLAB CORNERS 13. Field Fixes *For all-lightweight concrete, c a1 = c a2 = 2.95” (75 mm) Corner distance c ca2 is measured to the center of the anchor. Figure 2.2.3.2– Minimum corner distance for pair of HAC in top of slab, plan view. Design of Top of Slab Corners Figure 2.2.2.2 — Minimum corner distances for pair of HAC, plan view. Figure 2.2.3.3 Corner configuration of pair of HAC in top of slab. Cast-In Anchor Channel Product Guide, Edition 1 • 02/2019 49 Figure 2.2.3.3 — Premature concrete cracking due to simultaneous loading of pair HAC at corner with overlapped anchors, plan view. Additional measurements shall be taken into consideration to account for the negative influence of the adjacent anchor channel, if both channels are to be loaded simultaneously. See chapter 9, Special Anchor Channel Design for additional design information. The minimum corner distances for pair of HAC in top of slab corners (c ca2 ) are consistent with table 2.2.3.1. These minimum distances are based on installation requirements. Both HAC at corners cannot be installed at the minimum corner distance due to physical constraints (clashing of HAC will occur). However, two HAC can be installed next to each other in a view. AC232 does not include provisions to account for the influence of an adjacent and/or corner channel. Technically, HAC can be used in both sides of the corner. AC232 does not include provisions to account for the influence of an adjacent channel in a face of slab corner. Technically, HAC can be used in both sides of the corner, if there is no overlapping of the anchors. 48 Figure 2.2.3.1– Minimum corner distance for single HAC in top of slab, plan Pair of HAC in top of slab corners Pair of HAC in a corner Additional measurements shall be taken in consideration to account for the negative influence of the adjacent anchor channel, if both channels are to be loaded simultaneously. See chapter 9, Anchor Channel Design for additional design information. Although this solution is technically feasible, installing HAC at 4 to 7 inches away from the corner typically results in unpractical bracket sizes, large eccentricities, large forces, and consequently, inadequate concrete strengths. Figure 2.2.2.1– Minimum corner distance for single HAC in face of slab, plan view. Corner distance c a2 is measured to the center of the anchor. Hilti has developed a model to account for the influence of adjacent and corner channels. The model follows the fundamentals of AC232 and allows to analyze more complex but typical applications encountered in a project such as the conditions shown in Figure 2.2.3.3. See chapter 9, Special Anchor Channel Design for additional design information. Corner distance c a2 is measured to the center of the anchor. For face of slab applications, it is not recommended to install HAC in both sides of the corner if overlapping of the rounded head anchors occurs and simultaneous loading will be experienced. The overlapping of the anchors of the corner channels creates a weakened failure plane, making the corner susceptible to premature cracking and reduced concrete strengths. Corner distance c ca2 is measured to the center of the anchor.