In the system given, $k1=2197392\frac{N}{m},$

$k2=197392\frac{N}{m}.$ The value of mass $(m)$ is

$2500kg.$ The $1st$ Mode and $2$ nd Mode

frequencies of the structure are $1=6\mathrm{.}283$

$ra\frac{d}{s}$ and $2=12\mathrm{.}566ra\frac{d}{s}.$

a$)$ Find the periods of Mode $1$ and Mode $2[1$OP$]$

b$)$ Find the mode shapes. $[20$P$]$

c$)$ Find the modal participation coefficients. $[25$P$]$

d$)$ Spectral acceleration$-$period graph was

obtained for $2\%$ damping. The value corresponding

to the period value found according to the first

mode is $6\mathrm{.}17\frac{m}{s}2$ in the graph, and the value

corresponding to the second mode is $10\mathrm{.}582\frac{m}{s}2$

in the graph. Accordingly, find the base shear

force. $[20$P$]$