  Eclipsing binaries (EBs) are unique benchmarks for stellar evolution. On the
one hand, detached EBs hosting at least one star with detectable solar-like
oscillations constitute ideal test objects to calibrate asteroseismic
measurements. On the other hand, the oscillations and surface activity of stars
that belong to EBs offer unique information about the evolution of binary
systems. This paper builds upon previous works dedicated to red giant stars
(RG) in EBs -- 20 known systems so far -- discovered by the NASA Kepler
mission. Here we report the discovery of 16 RGs in EBs also from the Kepler
data. This new sample includes three SB2-EBs with oscillations and six close
systems where the RG display a clear surface activity and complete oscillation
suppression. Based on dedicated high-resolution spectroscopic observations
(Apache Point Observatory, Observatoire de Haute Provence), we focus on three
main aspects. From the extended sample of 14 SB2-EBs, we first confirm that the
simple application of the asteroseismic scaling relations to RGs overestimates
masses and radii of RGs, by about 15% and 5%. This bias can be reduced by
employing either new asteroseismic reference values for RGs, or model-based
corrections of the asteroseismic parameters. Secondly, we confirm that close
binarity leads to a high level of photometric modulation (up to 10%), and a
suppression of solar-like oscillations. In particular, we show that it reduces
the lifetime of radial modes by a factor of up to 10. Thirdly, we use our 16
new systems to complement previous observational studies that aimed at
constraining tidal dissipation in interacting binaries. In particular, we
identify systems with circular orbits despite relatively young ages, which
suggests exploring complementary tidal dissipation mechanisms in the future.
Finally, we report the measurements of mass, radius, and age of three M-dwarf
companion stars.
