  We study the local structural changes along the jamming transitions in
asymmetric bidisperse granu\-lar packings. The local structure of the packing
is assessed by the contact orientational order, $\tilde{Q}_{\ell}$, that
quantifies the contribution of each contact configuration (Large-Large,
Small-Small, Large-Small, Small-Large) in the jammed structure. The partial
values of $\tilde{Q}_{\ell}$ are calculated with respect to known ordered
lattices that are fixed by the size ratio, $\delta$, of the particles. We find
that the packing undergoes a structural transition at $\phi_J$, manifested by a
sudden jump in the partial $\tilde{Q}_{\ell}$. Each contact configuration
contributes to the jammed structure in a different way, changing with $\delta$
and concentration of small particles, $X_{\mathrm{S}}$. The results show not
only that the packing undergoes a structural change upon jamming, but also that
bidisperse packings exhibit local HCP and FCC structures also found in
monodisperse packings. This suggests that the jammed structure of bidisperse
systems is inherently endowed with local structural order. These results are
relevant in understanding how the arrangement of particles determines the
strength of bidisperse granular packings.
