The invention relates to a riveting element (R) for riveting parts which are made from composite materials (M1 and M2) and provided with a through-hole. The invention is characterized in that it consists of: a hollow bushing (200) including, at one end, a head (210) bearing on the surface of one of the parts to be assembled and a hollow rod (220); and a semi-tubular insert (100) including a first end (110) capable of being inserted into the hollow part of the bushing (200) and an open end (130) capable of deforming in order to form an enlarged base that bears on the surface of the other part that is to be assembled once the insert (100) is translatably locked inside the bushing (200). The invention also relates to the installation tool configured for one such element.