Product Technical Guides : US-EN Post-Installed Rebar Guide | January 2023 | Page 21

4.0 HOW DO I DECIDE WHICH SYSTEM TO USE
Post-Installed Reinforcing Bar Guide
Options for the installation of post-installed reinforcing bars include cementitious grouts , polymer adhesives , and hybrid systems that combine cementitious components with polymers . The use of cementitious ( e . g ., baseplate ) grouts is typically limited to down-hole applications and is not discussed further in this Guide . Adhesives ( sometimes referred to as thixotropic adhesives ) that have the correct viscosity to provide a void-free bond layer in the annular space between the bar and the concrete while still resisting unrestricted flow have been developed specifically for anchoring and bar embedment . These systems permit installation at all orientations with superior bond strength under a variety of use conditions . The proper selection of the system is dependent on a number of job-specific parameters .
4.1 SYSTEM SELECTION CONSIDERATIONS
Jobsite constraints impact both design values ( bond strength ) as well as installation effectiveness . Typical parameters for Hilti adhesive systems are shown below :
System selection is therefore dependent on the combination of design requirements and jobsite constraints . Note also that each system is offered with a variety of options for injection in terms of cartridge size and injection equipment ( manual vs . battery or pneumatic drive ). Additionally , Hilti offers specialized drilling systems that substantially reduce hole cleaning requirements . An aspect of system selection that is sometimes overlooked is the absolute volume of adhesive that must be placed in the hole . Large diameter and very deep holes may require a greater volume of adhesive than can be reasonably placed even with pneumatic delivery equipment . Furthermore , injection of large quantities of adhesive can result in excessive heat generation due to the exothermic nature of polymerization . These issues should be carefully considered for cases outside of the normal range of post-installed reinforcing bar applications .
Note : Hilti technical staff can provide assistance with unique or non-standard applications .
Jobsite constraints HIT-HY 200-R V3 1 HIT-RE 500 V3
Typical reinforcing bar diameter range
# 3 to # 8 # 3 to # 11 2
Embedment range Up to 25 in . Up to 7 ft .
Temperature of base material ( installation )
14 ° F to 104 ° F 23 ° F to 104 ° F
Working time 3 6 min . to 3 hrs . 12 min . to 4 hrs . Cure time 3 1 hrs . to 20 hrs . 4 hrs . to 72 hrs .
Holes drilled in dry and water-saturated concrete
Water-filled holes and underwater applications
Yes
No
Yes
Yes
Hammer-drilled holes Yes Yes Core drilled holes No Yes
Hilti SafeSet™ technology using Hilti HDB and VC vacuum
Yes Yes 4
Earthquake / dynamic loading
Yes
Yes
1 HIT-HY 200-A V3 ( accelerated cure ) available . Not suitable for larger bar diameters due to short gel time . 2 For larger bar sizes contact Hilti . 3 Temperature dependent . 4 Contact Hilti .
19 November 2022