Given a strictly concave rational PL function φ on a complete n-dimensional fan Σ, we construct an exact symplectic structure of finite volume on pC ˆqn and a family of functions H φ, called polyhedral Hamiltonians. We prove that for each the one-periodic orbits of H φ, come in families corresponding to finitely many primitive lattice points of Σ and determine their topology. When φ is negative on the rays of Σ, we show that the level sets of polyhedral Hamiltonians are hypersurfaces of contact type. As a byproduct, this construction provides a dynamical model for the singularities of toric varieties obtained as degenerations of Fano manifolds in any dimension via Okounkov bodies.