Projefct 1_Comparative study of different storey buildings for Seismic forces

• Effect of stiffness on T: Compare fundamental natural periods of buildings E & F as well as G & H. Why is there a marginal or significant difference in the fundamental natural periods?

The time period of E and F are 1.6891.622 . The time pperiod of both building arer same . The column sizes are different . The column are same in below building .

The time period of G and H are 4.527 and 4.802, as we can see that period of H is greater than G . The column size decreases as floor increases in the building (G) which leads to low flexibility compare to same column size distributation building H. Hence building H is more flexbile tahn building G.

If building height increase mass also increase as well stifness decreases .hence time period also increase.

Effect of mass on T: Compare fundamental natural periods of buildings H, J and K. Have the buildings become more flexible or stiff due to change in mass?

natural period of building H J and k are 4.802 ,4.29 adnd 4.3. When imposed loads are increased there is a slight increase in natural period ,building becoms more flexible as maass increase.

• Effect of Building Height on T: How does the fundamental natural periods of Buildings A, B, F and H change with change in building height?

The fundamental natural periods of Buildings A, B, F and H are 0.641, 1.162 , 1.162, 4.802 . if building height are increase time period increase .

• Effect of Column Orientation on T: How does the fundamental natural periods of Buildings B, C and D change with change in column orientation?

The fundamental natural periods of Buildings B, C and D 1.162, 1.151, 1.295. change in direction towards y axis increased time period . so column placed in longer direction.

• Effect of Axial Stiffness of Vertical Members on mode shapes: Compare fundamental mode shape of Building H in two situations when axial cross-sectional area of columns is very small versus when it is large.

Mode shape depends on axial stifness of vertical member in this case that is column.

change in axial stifness cause deformation in column.

• Effect of Degree of Fixity at column bases on mode shape: Compare fundamental mode shape of Building B in two situations when base of columns is pinned versus when it is fixed.

the fundamental natural period when hinged are fixed are 1.036 and 0.9.

When building is fixed at at the base. the rotational moment is restrict and also restricted the sway of building at the base

When building is hinged allows rotational moment.