[eng] The Standard Model of fundamental particles and their interactions is one of the most successful theories in physics. In particular, up to the weak scale (a few hundreds of GeV) it agrees to a great degree with a large set of experimental data. However, there are several theoretical reasons, such as the so-called "Hierarchy Problem", as well as experimental ones, such as the neutrino masses and the evidence for dark matter in the Universe, to expect that something new (particles and/or interactions) could lie at TeV scale. Hints and/or answer(s) to these fundamental questions will be provided by the Large Hadron Collider (LHC), a proton-proton collider running at high energies.
The present thesis aims to explore new physics at the LHC through phenomenological studies that employ simulations and computational tools to directly link theories with experimental data. In particular, the focus is on Beyond Standard Model theories that can incorporate a quantum description of gravity, such as extra dimensional theories, Supersymmetry and yet a simplified model where the constant of Newton is scale dependent. Phenomenological analyses are performed in which graviton and gravitino emission in combination with multiple jets are investigated at hadron colliders. Inclusive samples are generated by merging matrix element with parton shower descriptions, and validated by a comparison against next-to-leading order QCD calculations. Predictions for relevant observables at the LHC and Tevatron are obtained.