Seismic performance assessment of nylon lines for protecting museum collections

Abstract

While earthquakes pose a threat to both museum buildings and collections, the latter can be especially vulnerable. Seismic damage to museum collections can be minimized by securing objects with nylon lines, a widely used strategy in museums. However, this measure is usually adopted on the basis of the subjective interpretations by museum staff rather than scientific assessments of its efficacy, resulting in a lack of standardization. This paper aims to address this issue by proposing an appropriate assessment method on the basis of seismic risk analysis of museum collections. Specifically, the study first introduces a seismic fragility analysis method for the collection-showcase-museum system, which is a comprehensive method for evaluating the effectiveness of nylon lines in enhancing seismic performance. The seismic performance of the nylon lines can then be assessed through a seismic risk calculation of the museum collection. To demonstrate the effectiveness of the proposed method, a case study is conducted. Via numerical analysis, the study examined the impact of nylon line diameter, quantity, and tying angle on their seismic capacity. Moreover, this approach is used for an existing precious artifact in a Chinese museum to provide a practical reference for other museum collections. The findings of this study highlight the practical and scientific nature of the proposed method, indicating that larger diameter nylon lines significantly improve seismic performance. Additionally, collections secured with four nylon lines are more secure than those secured by fewer lines. The nylon lines with smaller tying angle may increases the probability of seismic damage to collections during strong earthquakes.