Overview
The preview research project AGB 2003/014 was able to show that the deformation capacity of existing Swiss piers is of fundamental importance for their seismic safety. In the case of new bridges, modern design provisions ensure that the piers possess enough deformation capacity by preventing brittle failure mechanisms (e.g. shear failure). However, those provisions call for a specific design and detailing of the piers which are typically not fulfilled by existing piers. For this reason some of the current models available to predict the cyclic-inelastic behaviour of the piers can not be directly applied to existing bridges.
It should be pointed out that this follow-up project was already part of the original proposal for AGB 2003/014 as an important contribution to the optimal completion of the latter.
The objective of the project is the in-depth investigation of the cyclic-inelastic deformation behaviour of bridge piers featuring configurations and seismic deficiencies typical for existing Swiss bridges from the 1960s. The findings of the research project AGB 2003/014 shall be extended by means of additional investigations.
Core of the project is the testing of a series of bridge pier models whose characteristics are complementary to those tested in the framework of AGB 2003/014. The need for additional testing was identified by the ongoing project and it is intended to provide an adequate basis for the development of sound mechanical models capable of realistically describing the seismic behaviour of existing bridge piers
- literature review,
- parametric study,
- investigation of the deformation behavior of wall-like reinforced concrete bridge supports
- analytical and numerical models,
- quasi-static tests on large-scale models
Funding
Results
This follow-up project to AGB 2003/014 starts with an experimental part in which about 4 new test units shall be tested. Important parameters, like e.g. shear span and transverse reinforcement content, that could not be investigated so far or for which adequate experimental evidence is missing (also internationally), will be taken into account during this subsequent campaign.
In a second phase of the project the results of both own and third party experiments shall be used to produce mechanical models capable of reliably predicting the cyclic-inelastic behaviour of existing bridge piers. First priority is to validate and, if needed, further develop the findings of AGB 2003/014. Such models are an indispensable condition for a modern displacement based assessment of existing bridges.
The key results are based on several tests:
- test results
- final report
- models
- recommendations
Technical Implications
It is intended to formulate the models developed and the recommendations drawn up so that they can be used directly in practice.