  Motivated by recent studies on the resurgence structure of quantum field
theories, we numerically study the nonperturbative phenomena of the SU($3$)
gauge theory in a weak coupling regime. We find that topological objects with a
fractional charge emerge if the theory is regularized by an infrared (IR)
cutoff via the twisted boundary conditions. Some configurations with nonzero
instanton number are generated as a semi-classical configuration in the Monte
Carlo simulation even in the weak coupling regime. Furthermore, some of them
consist of multiple fractional-instantons. We also measure the Polyakov loop to
investigate the center symmetry and confinement. The fractional-instanton
corresponds to a solution linking two of degenerate $\mathbb{Z}_3$-broken vacua
in the deconfinement phase.
