Experimental and Numerical Retrofitting of Confined Masonry Buildings with GFRP Under Lateral Cyclic Loading

Abstract This paper studies the structural performance of a retrofitted 3D confined masonry building. A non-retrofitted building was subjected to lateral cyclic loading until the first crack appeared in walls then retrofitted using woven textile glass fiber (GFRP), and the loading restarted until failure. Clay masonry walls, tie beams, tie columns, and R.C. slabs were used for construction then tested under lateral reversed cyclic loading. To study the effect of perforation on the structural performance of the building, the walls were constructed with different perforations, two solid walls, a wall with a door, and a wall with a window. This retrofitting technique was applied on the cracked specimen and then reloaded again under cyclic lateral loading. Results of a control non-retrofitted building with the same dimensions and perforations are used to be compared with our results, lateral resistance of the retrofitted specimen was increased by (26–32%) relative to the un-retrofitted reference specimen [4], as the maximum lateral load at the top of the building were + 217 and -195 kN for both push and pull cases, respectively, while the maximum lateral load of the un-retrofitted reference specimen [4] were + 165 and -155 kN for both push and pull cases, respectively, the maximum lateral displacement at failure was reduced by (23–31%). The total cumulative dissipated energy of the retrofitted specimen was improved by 60%, as the dissipated energy of the retrofitted specimen was 29.88 kN·m at max displacement of 44 mm while the dissipated energy of the un-retrofitted reference specimen [4] was 14.2 kN·m, ductility was improved by 60% while hysteresis damping of the building was improved by 78% compared to the un-retrofitted reference specimen. Diagonal shear failure was prevented and changed to sliding failure and the final collapse of the building was greatly delayed. A nonlinear finite element analysis is performed to verify experimental results and to predict results that are difficult to accomplish through this experiment. Good agreement is found between experimental and numerical results in terms of deformed shapes, shear failure, and lateral resistance. A parametric study is carried out to investigate the effect of all used parameters in the experimental test and study their effect on lateral behavior of the building.