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Distributed nonstructural elements (NSEs), such as piping systems, are restrained against seismic actions using proprietary or, at times, custom-designed braces. The strengths of these elements are provided in the component brochures published by the manufacturers, with no information on their deformation capacities. Previous research on the seismic performance of NSEs provide several formulations to calculate possible reductions in design force by relying on ductility capacity of their seismic restraints. However, designers require a realistic estimate of the ductility capacity of the seismic restraints to use these formulations. This paper discusses the results of a test program on the behavior of brace assemblies under monotonic tensile and compression loading. The results are used to identify the potential failure modes of the tested brace assemblies and to quantify their ductility capacity. Further, design examples are presented to highlight the need for the use of capacity design principles in the design of brace assemblies and their anchors. [ABSTRACT FROM AUTHOR]

This paper presents the concept and seismic performance of "rocking" internal partition walls with the dual-slot track (DST) and aluminium angles tested under quasi-static cyclic drifts. The DST is formed by tek-screwing two tracks of different widths to provide two separate slots for the studs and plasterboards. The horizontal joint, having a vertical gap, between the top DST and the wall allows it to rock up to the desired level of inter-story drift. Three planar wall specimens with plastered (comprising one and three layers of plaster) and sealant joints between the plasterboards remained undamaged until the designed drift level of 0.72%. Moreover, the "y"-shaped wall specimen with sealant joints exhibited a good bi-directional seismic behaviour avoiding significant damage like corner crushing and internal frame damage; hence validating the superior seismic resilience of this system. [ABSTRACT FROM AUTHOR]

This paper presents the concept, design, construction and seismic performance assessment of internal partition walls with novel slotted and bracketed head-track details. In the slotted head-track walls, the anchors connecting the wall to the slab above are intended to slide within the slot to accommodate the desired in-plane drifts. On the other hand, in the bracketed head-track walls, the story-drift demands are accommodated by sliding of the bolt and flexing of the plastic brackets attached to the slots. In this paper, bi-directional behaviour of a novel flexible bracket is experimentally characterised and a number of wall sub-assemblies with the slotted and bracketed connection details are tested under quasi-static cyclic loading to investigate their seismic performance. The walls with slotted details showed the first signs of damage requiring repair at 0.78% drift. In contrast, when brackets were attached to the slots, the wall remained intact up to 4% drift, demonstrating a superior seismic resiliency. [ABSTRACT FROM AUTHOR]

Artefacts in museums, galleries, and private collections have great cultural value. In regions with high seismicity, earthquake shaking can pose significant risk of irreversible damage to such pieces. Various seismic protection methods have been proposed in the past for different types of artefacts. This study investigates one of the commonly used methods in New Zealand which consists in applying adhesives to anchor relatively small artefacts. Guidance is provided to determine the size and number of adhesives required for an artefact to survive design-level earthquake shaking. In addition, for large objects where adhesives alone are insufficient, a simple cost-effective base-isolation platform is proposed to reduce the seismic vulnerability of the artefacts. This platform is designed such that it can be assembled and positioned by museum conservators or private collectors. The adhesive material properties are determined through direct tension and shear experimental tests. The friction properties of the base-isolated substrate are determined through unidirectional quasi-static and cyclic load tests. Performance of the proposed methodology is gauged by subjecting the artefacts to shake table testing using a recorded earthquake motion. Results suggest that the recommended seismic protection solution performs as expected. [ABSTRACT FROM AUTHOR]

This study experimentally investigates the reliability of testing idealized prisms to simulate failure mechanisms in RC walls. In-plane cyclic tests on three flexural walls with different transverse reinforcement detailing and axial tests on three rectangular RC prisms idealized as wall boundary zones are conducted and the experimental responses are discussed in this paper. The results confirmed that idealized rectangular RC prisms are susceptible to failure due to the development of global out-of-plane (OOP) instability. These investigations revealed that strain distribution along the height is a key parameter influencing the failure mechanism observed in wall boundaries and idealized prism specimens. [ABSTRACT FROM AUTHOR]

This paper reports the seismic performance of two 'rocking' internal plasterboard partition wall specimens comprising dual-slot tracks (DST) with a) sacrificial L-trim (SLT) joints and b) boxed end-studs and standard plastered joints investigated under quasi-static cyclic drift demands. The top gap between the top DST and the wall allows it to rock up to the desired level of inter-story drift. The SLT joints between adjacent plasterboard panels failed after the top gap in the DST was exhausted. The plaster cracks in the joints between the in-plane and out-of-plane plasterboard panels occurred early at 0.20% drift. However, the 'rocking' specimen with boxed end-studs exhibited a comparable seismic resilience to partition walls with horizontal seismic gap widths along the partition wall indicating that these gaps can be significantly reduced when the wall is allowed to rock using the DST details for the same inter-story drift capacities. [ABSTRACT FROM AUTHOR]