PSI - Issue 71

Nisha Thakur et al. / Procedia Structural Integrity 71 (2025) 233–240

239

Table 5: Maximum Bending Moment in Column in kN Seismic Load on various types of bracings Not provided Diagonal X-type (intersected) K-type

Floor Level

X-type

4 th 3 rd 2 nd

59.45 82.29 87.10

27.35 29.65 31.46 29.54 88.50

24.20 21.25 20.62 19.45 53.14

29.33 33.32 33.03 35.66 71.27

23.40 20.25 19.66 18.30 33.15

1 st

104.00 150.15

0

3.3. Analysis of Eight, Twelve, and Sixteen Storied Buildings From the above results obtained for the four-storied frame structure building, it was found that the X-type bracing system, compared to other types of bracings, is the most effective bracing system which not only reduces the lateral displacement but also the bending moments of the structures. Hence, an X-type bracing system is more useful for enhancing the strength of a high-rise building. Thus, the X-type bracing system is considered for the analysis of eight, twelve, and sixteen-storied buildings. These buildings are also analyzed for seismic zone IV. 3.4. Comparison of Lateral Displacement For the maximum lateral displacement in X and Z directions for G+4, G+8, G+12, and G+16 storied buildings, the results are observed. It shows that the result of displacement in lateral direction is reduced in the bracing system of X type and the percentage of reduction in lateral displacement decreases with the increase in the number of stories. The lateral displacement for G+4, G+8, G+12, and G+16 storied buildings in seismic zone IV are tabulated in Table 6. The table shows the lateral displacement and percentage reduction in braced frames in comparison to unbraced frames. Table 6: Maximum Displacements in X direction (mm) Number of Storeys Seismic Load % Reduction Bracing not Provided X-type Bracing 4 71.10 19.01 74.31 8 126.32 33.04 73.86 12 188.44 63.39 66.36 16 279.13 105.72 62.12 4.1. Reduction of Forces A steel-braced frame effectively reduces flexural and shear forces on beams and columns during seismic events. This is achieved by dissipating energy through the yielding of the braces, thereby protecting the primary structural elements from excessive damage. 4.2. Lateral Load Resistance The lateral forces produced during earthquakes are effectively transferred by the axial load mechanism of steel-braced frames. This process helps stabilize the building against sideways forces and reduces structural deformation. 4.3. X-type Steel Bracing The X-type bracing configuration is highly effective at reducing lateral displacements in buildings. By distributing the forces diagonally throughout the structure, this type of bracing minimizes sway and helps keep the building stable during earthquakes. 4.4. Minimum Shear force and Bending Moment Compared to other bracing systems, X-type bracing leads to lower shear force and bending moments on structural members. This is advantageous as it reduces the need for additional reinforcement, enabling the existing structures to better withstand the seismic forces. 4.5. Alternative to Other Technologies X-type steel bracing is seen as a substitute for other methods of retrofitting existing structures. It provides a good balance between effectiveness, cost efficiency, and effortless implementation, making it a first choice for many

4. Conclusions