  We perform a tomographic analysis of structure growth and expansion rate from
the anisotropic galaxy clustering of the combined sample of Baryon Oscillation
Spectroscopic Survey (BOSS) Data Release 12, which covers the redshift range of
$0.2<z<0.75$. In order to extract the redshift information of anisotropic
galaxy clustering, we analyse this data set in nine overlapping redshift slices
in configuration space and perform the joint constraints on the parameters
$(D_V, F_{\mathrm{AP}}, f\sigma_8)$ using the correlation function multipoles.
The analysis pipeline is validated using the MultiDark-Patchy mock catalogues.
We obtain a measurement precision of $1.5\%-2.9\%$ for $D_V$, $5.2\%-9\%$ for
$F_{\mathrm{AP}}$ and $13.3\%-24\%$ for $f \sigma_8$, depending on the
effective redshift of the slices. We report a joint measurement of $(D_V,
F_{\mathrm{AP}}, f\sigma_8)$ with the full covariance matrix in nine redshift
slices. We use our joint BAO and RSD measurement combined with external
datasets to constrain the gravitational growth index $\gamma$, and find
$\gamma=0.656 \pm 0.057$, which is consistent with the $\Lambda$CDM prediction
within 95\% CL.
