Table 19 — Hilti KB1 carbon steel design information in concrete in accordance with CSA A23.3 Annex D 1
Design parameter Symbol Units 3 / 8 1 / 2 5 / 8 3 / 4 A23.3-04
Anchor O . D . d a in . 0.375 0.5 0.625 0.75 ( mm ) ( 9.5 ) ( 12.7 ) ( 15.9 ) ( 19.1 )
Effective min . embedment 2 h ef in . 1-1 / 2 2 2 3-1 / 4 2-3 / 4 4 3-1 / 4 4-3 / 4 ( mm ) ( 38 ) ( 51 ) ( 51 ) ( 83 ) ( 70 ) ( 102 ) ( 83 ) ( 121 )
Min . concrete thickness h min in . ( mm )
Minimum edge distance c min in . ( mm )
Minimum anchor spacing s min in . ( mm )
See Table 5
See Table 5
See Table 5
Min . specified yield strength f ya psi 95,100 84,700 83,500 81,200 ( N / mm 2 ) ( 656 ) ( 584 ) ( 576 ) ( 560 )
Min . specified ult . strength f ut psi 118,900 105,900 104,400 101,500 ( N / mm 2 ) ( 820 ) ( 730 ) ( 720 ) ( 700 )
Effective tensile stress area A se , N in 2 0.053 0.103 0.164 0.239 ( mm 2 ) ( 34 ) ( 66 ) ( 106 ) ( 154 )
Steel embed . material resistance factor for reinforcement
Φ s
- 0.85 0.85 0.85 0.85 8.4.3
Resistance modification factor for tension , steel failure modes 3 R - 0.80 0.80 0.80 0.80 4 D . 5.3
Resistance modification factor for shear , steel failure modes 3 R - 0.75 0.75 0.75 0.75 4 D . 5.3
Factored steel resistance in tension N sar lb 4,315 7,385 11,670 16,520 4 D . 6.1.2 ( kN ) ( 19.2 ) ( 32.8 ) ( 51.9 ) ( 73.5 )
Factored steel resistance in shear V sar lb 1,620 3,330 5,675 6,865 4 D . 7.1.2 ( kN ) ( 7.2 ) ( 14.8 ) ( 25.2 ) ( 30.5 )
Factored steel resistance in shear , seismic V sar , eq lb 1,620 3,330 5,675 5,835 4 ( kN ) ( 7.2 ) ( 14.8 ) ( 25.2 ) ( 26.0 )
Critical edge distance c ac in . 8 5 6 10 11 9 12 11 ( mm ) ( 203 ) ( 127 ) ( 152 ) ( 254 ) ( 279 ) ( 229 ) ( 305 ) ( 279 )
Coeff . for factored conc . breakout resistance , uncracked concrete
Coeff . for factored conc . breakout resistance , cracked concrete k c , uncr
- 10.0 10.0 10.0 10.0 D . 6.2.2 k c , cr
- 7.1 7.1 7.1 8.8 D . 6.2.2
Modification factor for anchor resistance , tension , uncracked conc . 5 y c , N
- 1.0 1.0 1.0 1.0 D . 6.2.6
Anchor category - - 1 1 1 1 D . 5.3 ( c )
Ref
Concrete material resistance factor Φ c - 0.65 0.65 0.65 0.65 8.4.2
Resistance modification factor for tension and shear , concrete failure modes , Condition B 6 R - 1.00 1.00 1.00 1.00 D . 5.3 ( c )
Factored pullout resistance in 20 MPa uncracked lb
2,190 3,390 6,335
N concrete 7 pr , uncr n / a n / a n / a ( kN ) ( 9.7 ) ( 15.1 ) ( 28.2 ) n / a n / a D . 6.3.2
Factored pullout resistance in 20 MPa cracked lb
3,500 6,235
N concrete 7 pr , cr n / a n / a n / a n / a n / a n / a ( kN ) ( 15.6 ) ( 27.7 )
Factored pullout resistance in 20 MPa cracked lb
3,335 3,500 5,605
N concrete , seismic 7 pr , eq n / a n / a n / a n / a n / a ( kN ) ( 14.8 ) ( 15.6 ) ( 24.9 )
1 Design information in this table is taken from IAPMO ER-678 , dated December 1 , 2020 , Tables 4 and 5 , and converted for use with CSA A23.3 Annex D . 2 See Figure 1 of this document . 3 The KB1 is considered a ductile steel element as defined by CSA A23.3 Annex D section D . 2 , with the exception of the 3 / 4x12 KB1 which is considered a brittle steel element with R = 0.70 for steel failure in tension and R = 0.65 for steel failure in shear . 4 For the 3 / 4x12 KB1 , R = 0.70 for steel failure in tension and R = 0.65 for steel failure in shear . Multiply factored steel resistance in tension , N sar
, by 0.875 , and multiply factored steel resistance in shear , V sar , and seismic shear , V sar , eq
, by 0.87 .
5 For all design cases , Ψ c , N = 1.0 . The appropriate coefficient for breakout resistance for cracked concrete ( k c , cr
) or uncracked concrete ( k c , uncr
) must be used . 6 For use with the load combinations of CSA A23.3 chapter 8 . Condition B applies where supplementary reinforcement in conformance with CSA A23.3 section D . 5.3 is not provided , or where pullout or pryout strength governs . For cases where the presence of supplementary reinforcement can be verified , the resistance modification factors associated with Condition A may be used .
7 For all design cases , Ψ c , P
= 1.0 . Tabular value for pullout strength is for a concrete compressive strength of 2,900 psi ( 20.0 MPa ). Pullout strength for concrete compressive strength greater than 2,900 psi ( 20.2 MPa ) may be increased by multiplying the tabular pullout strength by ( f ́c / 2,900 ) n for psi , or ( f ́c / 20.2 ) n for MPa , where n is as follows : 3 / 8-in . diameter : n = 0.16 1 / 2-in . diameter : n = 0.23 5 / 8-in and 3 / 4-in diameter : n = 0.50 NA ( not applicable ) denotes that pullout strength does not need to be considered for design .
D . 6.3.2
D . 6.3.2
388 Anchor Fastening Technical Guide Edition 22 | 3.0 ANCHORING SYSTEMS | 3.3.9 KB1 EXPANSION ANCHOR Hilti , Inc . 1-800-879-8000 | en español 1-800-879-5000 | www . hilti . com | Hilti ( Canada ) Corporation | www . hilti . ca | 1-800-363-4458