PSI - Issue 71

Varsha Harne et al. / Procedia Structural Integrity 71 (2025) 279–286

285

4.5 Comparison of outcomes in terms of Maximum Stiffness

Table 5 . Stiffness of Analyzed Frames No. Model Characteristic

Bare Frame (kN/m)

Infilled Wall (kN/m)

Soft Storey (kN/m)

Ratio (Bare Frame / Infilled Wall)

1 Strong Beam-Weak Columns 189709.3

784001.1

768173.6

4.132

2 Weak Beam-Strong Columns 154441.6

1167244

1094471

7.557

(a) Prototype 1 (c) Prototype 3 Fig. 11. Evaluation of plastic hinge formation for G+10 storied RC buildings frames featuring with weak columns-strong beams at the final phase. (b) Prototype 2

(a) Prototype 4 (c) Prototype 6 Fig. 12 Evaluation of plastic hinge formation for G+10 storied RC buildings frames featuring with strong columns-weak beams at the final phase. Conclusions Based on the numerical analysis of multiple two-dimensional prototypes conducted in this study, the following conclusions emerge about the enhancement of seismic load resistance in reinforced concrete buildings through infill masonry walls: 1) The inclusion of masonry infill walls reduces the fundamental time period of a building. 2) For bare frame structures, the displacement demand is significantly high. However, infill walls enhance the building's efficiency by reducing storey displacement. 3) Multi-storey buildings with infill walls have a substantial effect on the stiffness and lateral resistance of the structure. Infill should be evenly spaced throughout the frame structure for best performance. 4) Infill walls significantly enhance the resistance of reinforced concrete structures designed with a weak column strong beam approach, with an increase of shear capacity of over 210%. In contrast, their impact is reduced to 50% in structures designed with a strong column-weak beam approach. 5) The study revealed that, in an earthquake-prone region, the uniform placement of infill walls throughout the height of buildings did not prevent the occurrence of the soft-storey phenomenon at the first-floor level, regardless of the column-to-beam size ratio. This was notably different from bare structures, where the phenomenon was more pronounced. (b) Prototype 5