Experimental fragility functions for exterior deficient RC beam-column connections before and after rehabilitation

  • Marthong, Comingstarful ;
  • Deb, Sajal K. ;
  • Dutta, Anjan
  • Received : 2016.01.13
  • Accepted : 2016.05.02
  • Published : 2016.06.25


The paper presents the development of experimental fragility functions for exterior RC beam-column connections based on results obtained from extensive testing carried out in the present study. Three typical types of seismically deficient beam-column connections, which are commonly prevalent in Indian sub-continent, were considered. These specimens were tested under cyclic displacement histories with different characteristics to induce different damage states. Rehabilitation specific fragility functions for damaged specimens were developed considering drift angle as a demand parameter. Four probability distributions were fit to the data and suitability of each distribution was evaluated using standard statistical method. Specimens with different damage states were rehabilitated appropriately and rehabilitated specimens were tested under similar displacement histories. Fragility functions for rehabilitated specimens have also been developed following similar procedure. Comparison of fragility functions for both original and rehabilitated specimens for each rehabilitation method showed close agreement, which establishes the effectiveness of the adopted rehabilitation strategies and hence would provide confidence in field application.


fragility functions;beam-column connections;damage states;demand parameter;rehabilitation;cyclic loading


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