Study of Failure Patterns in a Reinforced Concrete Beam Subjected to a Varying Range of Blast

Abstract

AbstractBlast load is assumed to cause local failure, which causes progressive collapse of structure globally. A reinforced concrete beam may experience failure in various forms, i.e., shear, flexure, and combined failure. P-I (Pressure-impulse) curves based on a single degree of freedom analysis are used to describe structural response against blast load. The design codes also suggest preparing P-I curves based on SDOF to obtain structural response subjected to blast. The structural dynamic response of R.C. flexure members for local analysis and complete structural frame for global analysis under a varying range of explosion scenarios was predicted by investigations. For distant blast, the model-based on flexure failure mode predicts approximately good results, while for near blast shear failure mode-based model understandably gives better results. A model based on one failure mode will not yield relatively accurate results for various blast ranges. The present study suggests that the model formulation that can capture both flexure and shear response yields an accurate response in the case of the near blast as well as distant blast, irrespective of the structure’s flexibility.KeywordsDistant blastNear blastLocal failureGlobal failureFlexibility