POST-EARTHQUAKE DAMAGE ANALYSIS OF REINFORCED CONCRETE FRAMED BUILDINGS

Abstract

In the present study, post-earthquake damage analysis of two reinforced concrete framed buildings, situated in A`ssm damaged during the North-East India Earthquake of August 6, 1988 have been performed- Dynamic analysis for the two buildings have been carried out using their mathematical models to determine their dynamic characteristics and to asses their performances during the earthquake. Results of the computer analysis show the structural -f de_ciencies with regard to their earthquake resistance and the reasons of the actual damages observed. The first building under the present study, the four storeyed reinforced concrete Post Office Building at Diphu, Assam was heavily damaged at the ground and first storeys, the most significant damage being the shear fai=re of many columns just beneath the floor levels. The computer analyses justify the observed damages showing that the shear stress developed during the ground shaking was much more higher than the actual shear capacity of the columns. For the second building, the staff quarter, Reserve Bank of India, Guwahati, Assam, the most significant damages were located in the region of articulation joint between the main~ building and the front staircase. The computer -analyses show that the expansion gap of 50mm provided was inadequate to accommodate the total out-of-phase displacement of the two seperate structures at the time of severe ground shaking.