He graduated as a civil engineer from the Faculty of Physical and Mathematical Sciences of the University of Chile in 1948, after publishing his memory of the title called "Oscilations of a high pond".
[2] In 1954 Arias became the director of Chile's first nuclear physics laboratory, built around a Cockroft-Walton multiplier, an accelerator for ionized particles.
In addition, he was director of the Institute for Research and Testing of Materials (IDIEM) between 1958 and 1965, a period in which he developed metal laboratories and industrial radiography.
[4][5] Its main contribution is considered "the most reliable instrumental measure used to date" and "used as a reference parameter" for anti-seismic engineering.
[8] The mathematical formula for Arias Intensity is: Following his investigations, the anti-seismic safety standards in Chile NCH433 Of.72 were established in 1972, successfully tested during the Santiago earthquake of 1985.