The Search for Hidden Particles (SHiP) experiment is a new general-purpose fixed target facility proposed at the CERN Super Proton Synchrotron (SPS) accelerator to search for long-lived exotic particles associated with Hidden Sectors and Dark Matter. This paper reports on the structural design of SHiP’s decay volume, a > 2000 m³ conical vessel under vacuum that should host several large particle physics detector systems. In the field of structural and seismic engineering, the design study in a very multidisciplinary international collaboration has represented a stimulating research challenge. The goal of the design of the decay is to produce a structure as light and as slim as possible to stay within the geometrical envelop determined in the physics simulations. A complete study has been performed with all the steps from the conceptual design, including the interaction with other components and the plant systems, to the assembly procedures for the decay volume realization. The complexity of the case study has been driven by the need of finding the appropriate compromise between the physics performance, the structural aspects, the executive, constructive and operational issues, and the economical constraints. The assembly strategy, the welding techniques, and the expected construction time are discussed in view of the extremely complex installation phase. Building Integrated Model (BIM) methodology is also proposed as an essential tool to coordinate the entire process of designing and managing not only the decay volume but the entire project.

搜索隐藏粒子（SHiP）实验是CERN超级质子同步加速器（SPS）加速器上提出的一种新型通用固定目标设施，用于搜索与隐藏扇区和暗物质相关的长寿命外来粒子。本文报道了SHiP衰减量大于 2000 m ³的结构设计真空下的锥形容器，应容纳多个大粒子物理探测器系统。在结构和地震工程领域，在非常多学科的国际合作中进行的设计研究代表了令人鼓舞的研究挑战。衰变设计的目标是使结构尽可能轻薄，以保持在物理模拟确定的几何包络范围内。从概念设计，包括与其他组件和工厂系统的相互作用，到实现衰变体积的组装程序，所有步骤均进行了完整的研究。案例研究的复杂性是由于需要在物理性能，结构方面，执行者，建设性和运营问题，以及经济限制。鉴于极其复杂的安装阶段，讨论了组装策略，焊接技术和预期的施工时间。还提出了建筑集成模型（BIM）方法，作为协调设计和管理衰减量乃至整个项目的整个过程的基本工具。