Concept Design Of Smart Mounted On GBS

Abstract

"In this study, we present a concept design for GBS (Gravity-Based Structure) type ONPP (Offshore Nuclear Power Plants) using SMART (System-integrated Modular Advanced ReacTor) model, which is the most recent SMR (Small Modular Reactor) model in Republic of Korea. Over the past few decades, there have been various attempts to operate NPPs in offshore. USA and USSR have developed floating type NPPs in 1950s. Recently, Russians are constructing a new floating type NPP, in which the KLT-40s reactor model is mounted. In addition, a submerged type NPP (e.g. FLEXBLUE) has been introduced by France. Since these floating and submerged type NPPs can be easily affected by severe ocean loads such as the Tsunami and storms, the new GBS type ONPP using APR1400, which is the largest NPP model in Republic of Korea, has been proposed in our previous work (Lee et al, 2012). In this study, we extend this concept for the SMART model and suggest the new concept with design parameters, design requirements, the new total GA (General Arrangement), and its structural safety features.

The main idea is that, to mount SMART, we adopt GBSs, which are widely used offshore structures. The SMR nuclear power plant model SMART has been developed by KAERI (Korea Atomic Energy Research Institute) in 2010. The ONPP can be launched and towed to the installation site after the SMART is constructed on GBSs in dry dock. In this phase, the foundation of installation site is prepared, simultaneously. At the end of this procedure, the ONPP is settled using de-ballasting system and then it can operate in offshore environment. The entire procedures with details are described in previous paper (Lee et al, 2011). Based on the concept, we introduce the new total GA of ONPP and its basic design parameters and requirements while minimizing modification to the original features of SMART such as physical connectivity, safety systems, building arrangements, area, volume and weight of buildings to simplify the entire iterative design process and make our concept feasible.

We categorize the structural safety features of ONPP corresponding to both internal and external hazards. The proposed ONPP concept can suffer from external hazards such as Tsunami, earthquake, wind, current drift, and storms. In addition, turbine missile strike induced from malfunctioned over-speed protection system of turbine blade should be protected. Since GBSs are usually made of reinforced concrete for safety and durability, structural safety features can be enhanced. Furthermore, ONPP can survive from severe sea environment conditions since our concept is retained by huge amount of its own weight.

We believe that the presented GBS type ONPP design concept based on SMART model can be a robust alternative to the original land based SMART."