BEAM COLUMN CONNECTIONS IN SMART STEEL FRAME SUBJECTED TO EFFECT OF DYNAMIC LOADS

Abstract

his study evaluates the seismic performance of steel frame with new type of partially restrained connection using shape memory alloy (SMA). superelastic form of shape memory alloy has large recoverable deformation upon removal the load is used in current study. The suggested connection consists of 16 steel bars and SMA bars (25.4mm) in diameter. 3D Finite element simulation using ABAQUS v.2017 software is developed, and their result was compared with an experimental test to validate the solution. This study aims to explore the effect of integrated SMA bars within frame on recentering ability, storey drift, residual storey drift, residual displacement, Energy dissipation, peak floor acceleration, stress and residual stress in the system. Eleven steel frame (one storey frame with two damage factor (10, 100) and two storey frame with three different combination of steel bars and SMA bars) (100% steel bars, 50% steel bars and 50% SMA bars, 100% SMA bars for each case), frame equipped with 100% steel bars was chosen as reference model. At the beginning of analysis, models were simulated under effect of free vibration and shows the six Eigen modes and frequency for one storey and two storey. 2 In case of one storey with damage factor =10 the addition SMA bars with percentage is (50%, 100%) instead of steel bars which lead to decease the residual roof displacement by (32.93%, 72%) respectively as compared with reference model , which also lead to decrease the stresses and residual stresses in frames. While increasing earthquake intensity for one storey cases for frame equipped with 50% SMA bars and 50% steel bars they enhance the recentering ability with ratio (83.5%) as compared with reference model, thus lead to reduction in residual displacement and residual storey drift by (47.08%) as compared with reference model. While in case of two storey frame , the results of numerical study shows that the adding SMA bars in frame instead of steel bars with ratio of (100%, 50%) improved strong recentering ability with the ratio (136%- 98%) respectively, as compared with reference model, in addition the reduction in residual roof displacement is (158.72%, 82.7%) in case of frame equipped with 100% SMA bars and frame equipped 50% SMA bars and 50% steel bars respectively, as compared with reference model. Also adding SMA bars instead of steel bars in frame lead to good contributes towards reduces the stress and residual stress.