PSI - Issue 78

Fabio Micozzi et al. / Procedia Structural Integrity 78 (2026) 1451–1458

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1. Introduction In seismic-prone areas around the world, children are instructed to hide under their school desks if an earthquake strikes. Such a recommendation implicitly assumes that the space below a school desk is a safe place to find protection in case the building hosting the classroom experiences some level of damage. Accordingly, school desks must be able to protect pupils from falling debris whose mass is highly uncertain, possibly ranging from parts of plaster, false ceilings, illumination, up to heavier non-structural or even structural elements of the upper floor. School desks can be made resistant to falling masses through an oversizing of their components. Many examples can be found browsing the internet, although the engineering and ergonomic quality of many designs is often questionable. Inevitably, the oversizing path produces desks that are bulky, very heavy, and generally much more expensive than conventional commercial models, thus, impractical for everyday school life and unaffordable by public administrations managing schools. The authors of this study worked within an interdisciplinary research project (“Sustainable design of anti-seismic furniture as smart life-saving systems during an earthquake”, acronym SAFE) funded by the Italian Ministry of University and Research (PON 2018-2021 Research and Innovation, Area of Design, Creativity, and Made in Italy) in close collaboration with designers and industrial producers of school furniture, to create an innovative solution that is economically competitive. The research development brought to a solution where steel tubulars of diameter 22 mm and thickness of 1.5 mm (elements commonly used for school furniture) are arranged in an innovative shape able to emphasize structural performance (Fig.1).

Fig. 1. Dual frame SAFE school desk.

An external frame provides direct support to the tabletop and an inner frame with similar geometry is connected to the outer frame at the four corners and at the basis, along the shorter sides of the desk. The outer and inner frames constitute a redundant structural system and collaborate with a bending progressive damage in case of strong overloading. A steel sheet having thickness 1 mm and perforated to reduce its weight is welded at the top of the outer frame to protect from objects that might hit and penetrate the plywood tabletop. The resulting desk is much lighter as compared to existing earthquake-proof desks, more economical being based on materials, sections, dimensions of elements and manufacturing processes already adopted in common school furniture, does not have moving components that could harm users, has a bending-dominated damage in case of significant overloading that exploits the ductility of steel to dissipate impact energy while preserving the volume of the protection area. The developed dual-frame configuration was patented (University of Camerino et al. 2021, Patent EP4059378A1). In addition, the proposed school deck was equipped with dissipative steel feet at the interface between the bottom of the dual-frame and the floor, feet designed to yield for a force below the axial capacity of the desk legs, to further dissipate impact energy. The developed dissipative feet were also patented (University of Camerino et al. 2022, Patent IT202200003099U1).