Nakashima has served on many AIJ research committees as chair or technical secretary, including the Disaster Response Committee, AIJ Journal Editorial Committee, and the Steel Building Committee. He served on the board of directors in charge of foreign affairs for the Japan Association for Earthquake Engineering (JAEE) (2001 to 2003) and helped establish the partnership agreement between EERI and JAEE. He belonged to the Building Center of Japan’s Peer Review Panel for the design of base-isolated buildings (1995 to 2005). Since 2003, he has chaired the Review Panel of the Architecture and Building Engineering Program of the Japan Accreditation Board for Engineering Education (JABEE, equivalent to U.S. ABET).

Nakashima’s fields of research include the inelastic, stability, and collapse behaviour of steel members and frames, seismic analysis and design of steel building structures, experimental techniques for simulating the earthquake responses of large structural systems, and the seismic design of base-isolated buildings. He and his students have published some 250 technical papers, over 100 of them in archival journals.

Nakashima has received seven national research awards, including Best Paper Prize of AIJ (1997), Best Paper Award of the Japan Society for Steel Construction (JSSC) (1999, 2000, 2004), and the Moisseiff Award of the American Society of Civil Engineers (2000). He is editor of the International Journal of Earthquake Engineering and Structural Dynamics (EESD), the official journal of the International Association for Earthquake Engineering (IAEE).