-BASE | Opportunities for Additional Graduation Work (CIE5050-09)

Opportunities for Additional Graduation Work (CIE5050-09)

Creep Behaviour of Resin used in Injected Bolted Connections

Injection bolts have been used successfully in engineering practice to prevent slip (relative displacement between members) in bolted shear connections. Slip is prevented by epoxy resin that is injected through the specially designed bolt head into the bolt-to-hole clearance. Injected bolted connections are an alternative to preloaded bolted shear connections, and have the advantage that no preparation of the faying surfaces is required. This allows for easy application of injection bolts in new structures or existing connections (e.g. during renovation). In case of connections with large fabrication or execution tolerances, any remaining gap can be filled using epoxy. An example of such application is the shear connection between a prefabricated concrete slab and a steel beam. Research in the field of injection bolts at TU Delft started in the 1970s, and currently is a high priority in order to achieve demountable and reusable composite structures to reduce both waste and CO2 emissions. One of the challenges is to determine the creep behaviour of the epoxy resin, because creep negatively affects the (effective) stiffness of injected bolted shear connections.

We are looking for a student interested in injected bolted shear connections, and we have the following challenges to be solved within an Additional Master Thesis (CIE5050-09):

Developing of a test set-up for a uniaxial creep test on epoxy resin (RenGel SW404 + HY2404)
Determining the creep behaviour of epoxy resin at various stress levels
Fitting the experimental creep behaviour to a creep model using finite element software (ABAQUS)
Comparing creep behaviour observed in tests (results available) on injected bolted steel- to-steel shear connections to predictions based on finite element analysis
Determining the positive effect of material connement and the resulting multiaxial stress state on the reduction of creep-induced slip

For more info please contact:

ir. M.P. (Martin) Nijgh | M.P.Nijgh@tudelft.nl
prof.dr.ir. M. (Milan) Veljkovic | M.Veljkovic@tudelft.nl