Modelling the seismic response of RC bridge piers with lap splices in the plastic hinge region

• Forschungsstelle: ASTRA SBT
• Projektnummer: AGB2015/002

Schlüsselwörter (Englisch)

Bridge piers, seismic response, reinforced concrete, lap-splice, modelling

Kurzbeschreibung (Englisch)

- Understand the behaviour of lap-splices when subjected to cyclic loading. A series of uni-directional monotonic and cyclic tests on lap-splices will be carried out to complement previous large-scale tests on entire piers. The objective is to develop and calibrate a model for the cyclic degradation of lap-splice strength.
- Validate the plastic hinge model for bridge piers against a larger data set: The plastic hinge model by Hannewald (2013) was validated against the three wall tests with lap splices that were carried out within the two FEDRO projects. The model will be improved based on the new experimental results. To validate the model further, all tests on walls with lap splices that are reported in the literature have been compiled and will be used for model validation.
- Develop a computationally efficient tool for the analysis of bridges with column-type or wall-type piers by means of nonlinear beam element models. A new beam element will be developed and implemented in the open source code OpenSEES and is hence publically available.
- Provide modelling recommendations for performance-based assessment of bridges with nonlinear beam elements, in order to stimulate a generalized and reliable use by researchers and engineers when modelling the seismic response of RC bridges.
- The project builds on the two previous FEDRO projects:
Bimschas, M., Dazio, A., 2014. Seismic safety of existing bridges, Report on the FEDRO research project AGB 2003/014. Bern, Switzerland.
Hannewald, P., Beyer, K., 2014. Seismic Safety of Existing Bridges – Cyclic Inelastic Behaviour of Bridge Piers, Report on the FEDRO research project AGB 2008/001. Bern, Switzerland.

Projektziele (Englisch)

Most bridges in Switzerland were constructed before modern seismic design provisions were in place. As a result, the longitudinal reinforcement of reinforced concrete (RC) column- or wall-type bridge piers are spliced at the base, where plastic hinges are expected to form in the event of a significant earthquake. Cyclic tests on RC bridge piers with lap-splices have shown that microcracking can lead to a sudden strength loss of the lap-splice. The project aims at contributing to the understanding of the behaviour of lap-splices under cyclic loading and at developing computationally efficient tools for the nonlinear analysis of RC bridges.

Berichtsnummer (Deutsch)

711