Blast Retrofitting of Reinforced Concrete Structures Using Jacketing Schemes

In the present study a case study is discussed incorporating the retrofitting techniques primarily in the form of reinforced concrete (RC) jacketing to enhance the structural stability and strength of civil engineering structures damaged under violent forces generated by the blast vibrations. Finite element approach is adopted to analysis and design the structure with finite element software ETABS. The case study considers an existing five storey reinforced concrete building located in the vicinity of frequent mining activities making the structure vulnerable to blast induced damages. The structure is designed considering the conventional loadings namely dead loads, live loads, and seismic loads along with the seismic load combinations. The study explores the performance of a seismically safe building subjected to underground blast induced vibrations. The objective and novelty of the study is to evaluate the deficit demand of the structure against the blast induced in terms of flexural and shear demand of the existing structure. The study compares the structural performance of the building in terms of shear force and bending moment under seismic and blast loadings. The study suggests retrofitting the failed members with RC jacketing to avoid such failures. Retrofitting the structure resulted in the reduction of displacement values by 31% when subjected to blast induced vibrations when compared with without retrofitting structure. The demand capacity ratio is also evaluated for with and without retrofitting condition and it is observed that retrofitting technique is an excellent method in improving the performance of the building damaged due to blast vibration.