Dynamic properties and seismic performance of an innovative cleanroom.

A cleanroom or white room is a constructed facility having a controlled environment in terms of cleanliness, temperature, humidity, and pressure. Cleanrooms are used in various industrial contexts to implement activities that require strictly controlled environment and minimum air contamination. Typical applications refer to food, pharmaceutical, and electronic industry, as well as to healthcare facilities. Cleanrooms are considered nonstructural elements (NEs) since they are not part of the structural systems of the buildings; they are extremely complex and include architectural, mechanical, hydraulic, and electrical/electronic components. Several recent earthquakes in Italy and worldwide highlighted the potential vulnerability of complex NEs such as the cleanrooms. In particular, their damage potentially results in heavy economic losses related to both direct losses (e.g., repair cost) and indirect losses (e.g., downtime) and casualties. No literature studies investigated the seismic performance of cleanrooms, and no regulations or guidelines define reliable methods for assessing their dynamic properties and seismic capacities. This study investigates the seismic response of an innovative cleanroom, in terms of both dynamic properties and seismic performance. Shake table tests are performed on a full-scale innovative cleanroom under operation conditions. In particular, the cleanroom testing setup included walkable ceiling system and ventilation/electrical/piping network systems. The experimental investigation consists in both dynamic identification and incremental seismic performance tests, according to ICC-ES AC156 protocol. The cleanroom was proven to have high seismic capacities under operation conditions. The developed construction and technologic solutions, including innovative devices, represent guidance towards the implementation of seismically safe cleanrooms.