Earthquake is the most dangerous and unpreventable natural occurrence, wreaking destruction on buildings, resources, and people's lives. Earthquake loading is extremely variable and is determined by the length, magnitude, and frequency of seismic waves. The number of stories, soilstructure contact, stiffness, mass of the structure, vertical, plan, and tensional disturbances and reentrant corners are all variables that influence how structures respond to earthquakes. Retrofitting is the process of strengthening and improving the efficiency of defective structural components or the whole building. The aim of retrofitting is to improve a building's structural integrity after or before an earthquake to achieve a predetermined level of efficiency. A retrofitted building's seismic strength is comparable to that of the original structure. Complete restoration will be prohibitively expensive. The total cost of redeveloping the house will be significantly greater than the cost of retrofitting.
In the present study a G+6 storey Hospital building retrofitting is carried out which is located in Karimnagar city Telangana State. The building was located in low seismic zone II the analysis is carried out by using SAP 2000 software by Response spectrum method. The results like joint displacements, lateral loads, shear, bending, torsion, time period and frequency values are compared with existing structure and retrofitting structure.
Key words: Earthquake, Retrofitting, Seismic strength.