Product Technical Guides : US-EN Post-Installed Rebar Guide - Page 13

Post-Installed Reinforcing Bar Guide
2.0 HOW ARE THEY DESIGNED ?
( N ) 4 - # 9 top bars embedded in drilled holes with Hilti HIT-RE 500 V3
( N ) 14 x 20 in . beam
20 in . ( E )
51 in .
( N ) 14 x 20 in . beam Roughened surface , 1 / 4 in . amplitude
( N ) 4 - # 9 top bars embedded in drilled holes with Hilti HIT-RE 500 V3 roughened surface , 1 / 4 in . amplitude
( N ) drilled-in dowels
24 in .
( E ) foundation reinforcing
Figure 16 — Beam to column detail ( not to scale ). Figure 17 — New column on existing foundation .
Step 4 : Specification Provide post-installed bars at size , spacing and embedment as indicated on construction documents ( Figure 16 ).
Dowels : ASTM A706 Grade 60
Anchoring system : Hilti HIT-RE 500 V3 epoxy , install as per Manufacturer`s Printed Installation Instructions ( MPII ), permissible concrete temp . range for installation : 55˚F - 90˚F , concrete shall be dry during dowel installation .
Drill holes using a rotary-hammer drill with carbide bit . Locate existing reinforcing prior to drilling — do not damage ( E ) reinforcing without prior authorization of the EOR .
Step 2 : Determine the development length for the column bars . Note that the confinement term can be taken as the maximum value of 2.5 given the edge distance and confinement condition .
Eq . ( 25.4.2.4a ):
l d
3 f y ψ s ψ t ψ e ψ
= g d b
= 3 60000 1 . 0
40 λ c b
+ K 40 1.0√4000 2.5 tr d b
0 . 875 = 25 in .
2.6.4 DESIGN EXAMPLE — DEVELOPMENT LENGTH FOR COLUMN STRUCTURAL JOINT
Requirement : Provide post-installed structural joint for a new column on an existing foundation .
( N ) 4 - # 7 dowels embedded in drilled holes with Hilti HIT-RE 500 V3
( N ) column
roughened surface , 1 / 4 in . amplitude
Step 1 : Establish requirements for the new bars . Existing construction : Foundation grade beam 24 x 36-in ., 4 ksi concrete , A615 Gr . 60 reinforcing
New construction : ( N ) 18 x 18-inch column as shown , 4 ksi normal weight concrete , ASTM A615 Gr . 60 reinforcement , 4 - # 7 column bars
25 in .
( E ) foundation reinforcing
( E ) Grade beam
The column resists moment and shear arising from wind loading .
Figure 18 — Column to grade beam detail ( not to scale ).
11 2021