Technical report on the structural integrity and the lifetime evaluation for the mercury target vessel

Ishikura, Shuichi*; Futakawa, Masatoshi  ; Kogawa, Hiroyuki  ; Meigo, Shinichiro   ; Maekawa, Fujio  ; Harada, Masahide   ; Sato, Hiroshi; Haga, Katsuhiro  ; Ikeda, Yujiro

This report describes the structural design concept applied to the mercury target vessel used for the spallation neutron source installed in the material and life science experiment facility of J-PARC (Japan Proton Accelerator Complex), and the results evaluated on the basis of the concept. The features of the design concept are as follows: (1) The target vessel design is followed to "Law concerning Prevention from Radiation Hazards due to Radio-Isotopes". That is because (i) there is not the possibility in the target of the RIA (Reactivity Initiated Accident) generally considered in the nuclear power reactors, and (ii) the target vessel is not a permanent structure. (2) Therefore, the Class 1 Vessel of the JIS B-8270 [design code for pressure vessel] that is equivalent to a standard for nuclear power structural design is applicable as a design code for the target to sufficiently keep the safety of target system. The stresses for the design were evaluated using the linear elastic analysis based on the infinitesimal strain theory in order to confirm the safe and rational design.