  Following the discovery of the Higgs boson at LHC, new large colliders are
being studied by the international high-energy community to explore Higgs
physics in detail and new physics beyond the Standard Model. In China, a
two-stage circular collider project CEPC-SPPC is proposed, with the first stage
CEPC (Circular Electron Positron Collier, a so-called Higgs factory) focused on
Higgs physics, and the second stage SPPC (Super Proton-Proton Collider) focused
on new physics beyond the Standard Model. This paper discusses this second
stage.
