  In this article, we have investigated the role of bulk viscosity to study the
accelerated expansion of the universe in the framework of modified $f(Q)$
gravity. The gravitational action in this modified gravity theory has the form
$f(Q)$, where $Q$ denote the non-metricity scalar. In the present manuscript,
we have considered a bulk viscous matter-dominated cosmological model with the
bulk viscosity coefficient of the form $\xi =\xi _{0}+\xi _{1}H+\xi _{2}\left(
\frac{\dot{H}}{H}+H\right) $ which is proportional to the velocity and
acceleration of the expanding universe. Two sets of limiting conditions on the
bulk viscous parameters $\xi _{0},$ $\xi _{1},$ $% \xi _{2}$ and model
parameter $\alpha $ arose here out of which one condition favours the present
scenario of cosmic acceleration with a phase transition and corresponds to the
universe with a Big Bang origin. Moreover, we have discussed the cosmological
behaviour of some geometrical parameters. Then, we have obtained the best
fitting values of the model parameters $\xi _{0},$ $\xi _{1},$ $\xi _{2}$ and
$\alpha $ by constraining our model with updated Hubble datasets consisting of
$57$ data points and recently released Pantheon datasets consisting of $1048$
data points which show that our obtained model has good compatibility with
observations. Further, we have also included the Baryon Acoustic Oscillation
(BAO) datasets of six data points with the Hubble \& Pantheon datasets and
obtained slightly different values of the model parameters. Finally, we have
analyzed our model with the statefinder diagnostic analysis and found some
interesting results and are discussed in details.
