Post-Installed Reinforcing Bar Guide
2.0 HOW ARE THEY DESIGNED ?
Step 3 : Specification Provide post-installed bars at size , spacing and embedment as indicated on construction documents ( Figure 18 ).
Dowels : ASTM A615 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 .
2.6.5 DESIGN EXAMPLE — DEVELOPMENT LENGTH FOR STRUCTURAL JOINT IN A SPECIAL STRUCTURAL WALL
Requirement : Provide a structural joint for a new special structural ( shear ) wall in SDC D . distance and confinement condition . Also , per 18.10.2.3 ( b ) of ACI 318-19 , the development length must be increased by 25 % to account for possible over strength in the bars .
l d
3 f y ψ
= s d b
= 1.25 40 λ c b
+ K tr roughened surface , 1 / 4 in . amplitude d b
Step 3 : Determine the development length for the # 8 vertical wall bars , which are assumed to be exempt from the 1.25 increase factor of 18.10.2.3 ( b ).
3 60000 1.0 l d
= 1.0 = 26 in .
40 1.0√5000 2.5
A-A
A A
3 60000 1.0 40 1.0√5000 2.5
( N ) # 8 drilled-in rebar embedded in drilled holes with Hilti HIT-RE 500 V3 , 12 " OC , typ .
B
1 . 27 = 40 in .
|
A-A
A
|
A
roughened surface , 1 / 4 in . amplitude
|
B |
( E ) FDN |
( N ) 7 - # 10 drilled-in rebar embedded drilled holes with Hilti HIT-RE 500 V3 |
40 in . |
26 in . |
( N ) drilled-in rebar
( E ) mat foundation ( E ) mat foundation
B-B Figure 19 — New special structural wall .
B elevation
Step 1 : Establish requirements for the new bars . Existing construction : Foundation mat 4-ft . thick , 5 ksi concrete , A615 Gr . 60 reinforcing .
New construction : ( N ) 18-inch thick wall detailed and constructed in accordance with 18.10 of ACI 318-19 , two curtains of steel , boundary member reinforcement per 18.10.6 , 6 ksi normal weight concrete , ASTM A706 Gr . 60 reinforcement , boundary member reinforcing 7 - # 10 bars , web reinforcing is # 8 @ 12 in . on center vertical and # 6 @ 10 in . on center horizontal ( see Figure 19 ).
Step 2 : Determine the development length for the # 10 chord bars . As in the previous example ( 2.6.3 ) the confinement term can be taken as the maximum value of 2.5 given the edge
B-B
Figure 20 — Wall to foundation detail ( not to scale ).
B elevation
Step 4 : Specification Provide post-installed bars at size , spacing and embedment as indicated on construction documents ( Figure 20 ).
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 .
Note : Hilti maintains a staff of qualified engineers available to answer inquiries related to design and installation of postinstalled reinforcing bar connections .
12 November 2022