Seismic Fragility Estimation Of Corroded Reinforced Concrete Frame Structures

In recent years, more and more attention is paid on the durability of reinforcedconcrete structures by researchers all over the world. The reinforcing bar corrosion isthe prevalent factor deteriorating the durability of reinforced concrete structures,which has caused tremendous economic loss all over the world. In the past30years,considerable efforts have been made on the research of reinforcing bar corrosion.However, regarding the existing researches, there are still some deficiencies, such asneglecting some necessary damage, missing validating with experimental data andmissing the probabilistic seismic performance estimation of corroded reinforcedconcrete structures. In order to improve these problems, some work has been finishedin this thesis:(1) The damage of corroded reinforced concrete structures covers many aspects,i.e. nominal strength of reinforcing bar, compressive buckling of reinforcing bar,concrete cover, concrete core and bond-slip relationship. Through modifying thematerials’ stress-strain relationships, a fiber based model was established to simulateseismic performance of reinforced concrete structures, which was validated withselected experimental data of corroded reinforced concrete structures subject toreversed loadings.(2) Regarding the issue “whether the corrosion damage has remarkable influenceon the seismic performance of reinforced concrete structures”, different researchershave drawn contrary conclutions. Seismic fragility of a simple corroded reinforcedconcrete pier was conducted, concluding that reinforcing bar corrosion remarkablydeteriorated seismic performance of reinforced concrete structures.(3) The behaviour of IDA curves is complicated such as back-and-forth twisting,non-monotonic and platform behavior. In order to improve this problem, a Bayesianmethodology based method was proposed for statistical analysis of IDA curves.(4) Uncertainty is the physical nature of ground motion. IDA is an efficientmethod to calibrate ground motion uncertainty. An IDA based method was proposedto estimate seismic fragility of corroded reinforced concrete frame structures.