Seismic Analyses Of The ADS Zero-power Facilities

Accelerator Driven System(ADS) offers interesting transmutation possibilities. The combination system of the proton accelerator and the sub-critical reactor can be used for the spent fuel transmutation utilizing high energy neutrons in reactor core. Two sets of the zero-power facilities are constructed for the ADS design and operational verification. One is the lead zero-power facility; the other is the water one. Due to the hazard of the radioactive material, the safety assessment of the nuclear devices is particularly important. The mechanical properties of the ADS zero-power facilities need to be assessed. During earthquake, the localized stress of mechanical structures will increase due to vibration, which is a risk for the structural integrity. The detailed stress assessment of the seismic analysis is needed to be done the under the hypothetical earthquake conditions.The finite element model of the ADS zero-power facilities is constructed to perform dynamic evaluation using the ABAQUS code. Since the ADS zero-power facilities have complex internal structures, with the method of the equivalent quality, the geometric model is simplified. The three-dimensional frame model of the ADS zero-power facilities consists of line bodies and face bodies without solid bodies. The square root of square sum calculation method is chosen to combine modes in response spectrum analysis. The first principal stress of the vessels and the support legs stress are evaluated. Both the water and the lead zero-power reactor core vessels meet ASME-III-ND specification. The support leg stress assessment meets the requirements of ASME-III-NF. The ADS zero-power facilities would maintain structural integrity during the hypothetical earthquake.