Post-Installed Rebar - Product Qualification [Part 2]

Test on Installation Safety in Dry & Wet concrete

Installation safety test investigate the influence of reduce cleaning effort in dry & wet concrete. The installation procedure during the test is simplified to simulate the lack of cleaning effort in jobsite. Please note that even the product passed the installation safety test, it does not imply the installation can be done will less cleaning effort. The adhesive should be installed according to manufacturer's specification under all condition.

Test on Installation Direction & Injection

Installation direction and injection are some of the major concerns during installation. While cementitious grout has a lower viscosity and consistency, horizontal and vertical upward application will significantly increase the amount of void in the drilled hole. Only adhesive with suitable viscosity can have least amount of void thus maintaining the performance of rebar.

What the new assessment document EWAD330087, what are the major difference?

In the new assessment document, there are more tests to be conducted that TR023. Some tests are transferred from the old TR 023 while some are added due to new consideration and therefore there is increased number of tests specified.

Sustained Load Test

One of the transferred tests is the sustained load test which investigate the impact of sustained load on displacement. Loading is applied and the test sample is kept at service temperature. The displacement is measured over a period time, i.e. at least 3 months.

Creep behavior of adhesive anchoring systems

The phenomenon of slow and continuous deformation of a metrial under sustained stress is categorized as creep behavior, and the key factors are the material/ product properties, loading and temperature. If the temperature, magnitude of loading and loading duration increase, the creep displacement will also increase. Looking at the displacement-time graph, the initial displacement is more significant and while time progress, the rate of displacement will be reduced and stabilized.

100 years service life for concrete-to-concrete connections

The result obtained from sustain load test is related to the service life of the connection. In order to obtain service life test for 100 years, a sustained load test of 6 months must be carried out. 

Fire Resistance condition

Fire resistance is a new consideration in EAD document. As discussed, under the fire condition, different structure will have different temperature profile and adhesive will subject to different degree of heat transfer. Therefore, the relationship between the performance reduction and temperature must be identified in order to give an accurate Fire limit state (FLS) design.

[To be continued...]