  This paper describes simulations of detector response to multi-TeV physics at
the Future Circular Collider (FCC-hh) or Super proton-proton Collider (SppC)
which aim to collide proton beams with a centre-of-mass energy of 100 TeV. The
unprecedented energy regime of these future experiments imposes new
requirements on detector technologies which can be studied using the detailed
GEANT4 simulations presented in this paper. The initial performance of a
detector designed for physics studies at the FCC-hh or SppC experiments is
described with an emphasis on measurements of single particles up to 33 TeV in
transverse momentum. The reconstruction of hadronic jets has also been studied
in the transverse momentum range from 50 GeV to 26 TeV. The granularity
requirements for calorimetry are investigated using the two-particle spatial
resolution achieved for hadron showers.
