UTILIZING EAD 330087 AND EAD 332402 FOR YOUR REBAR DESIGNS

Background
A new post-installed rebar design method TR069 had been published in 2019 by EOTA and it has several differences compared to the traditional design method mentioned in Eurocode EN1992-1. Let’s get started!

The differences in design theory
The new TR 069 combines reinforced concrete design principles (EN1992-1-1) with anchoring to concrete principles (EN1992-4). Design following TR 069 is only possible if injection systems are assessed according to EAD 332402. An assessment according to EAD 330087 is not sufficient. Within TR 069 the individual failure modes of the system connection are explained in detail. They are:
 

• Rebar steel yielding
• Concrete cone
• Bond splitting

 
The design is based on the hierarchy strength design principle, i.e., the lowest resistance of the individual failure modes is decisive. Yielding of the steel, concrete cone failure and bond-splitting failure of the post-installed rebar connection must be verified. In addition, the requirements of EN1992-1-1 in terms of minimum anchorage length must be fulfilled. In addition, TR 069 works within the following framework:
 

• The TR 069 provides a design of the post-installed rebar’s anchorage length. The load transfer between new and existing concrete members shall be verified in accordance with EC2 (e.g., shear transfer at the interface and shear resistance of connecting member as well as nodal panel)

• This technical report covers post-installed rebar connections in reinforced or unreinforced, normal weight, non-carbonated C20/25 to C50/60 concrete

• During the assessment process, the bond-slip behavior for different concrete cover is tested. The resistance corresponding to bond-splitting failure, and its relevant parameters, are provided in the product ETA and obtained following the qualification process of EAD 332402.

• The safety concept (i.e. partial safety factors) adopted in TR 069 is the same as in EC2-1 (for steel yielding) and EC2-4 (for concrete cone and bond-splitting failure modes), which ensure a high level of compatibility of the design output in accordance with TR 069 with the EC2

Below table summarizes the differences comparing the TR 069 versus the EN 1992-1 & the EN 1992-4.

 
If you would like to start designing as per TR069, you can use the Hilti PROFIS Rebar software. Visit the PROFIS Rebar webpage by clicking here