Without additional design considerations, such as structural robustness, the failure of a building’s structural element can develop into a progressive and/or disproportionate collapse. The existing requirements given in international guidelines for preventing disproportionate collapse are generally not practical and uneconomic when applied to multi-storey cross-laminated timber (CLT) buildings in platform-type construction. This paper summarises recent research and improved approaches developed to meet structural robustness for such buildings. To ensure alternative load-paths using simplified linear elastic analytical procedures, an improved method using engineering mechanics was derived for CLT buildings in platform-type construction to aid in quantifying connection tie forces between structural components. Using advanced nonlinear dynamic analyses, the behaviour of two case-study buildings under element removal scenarios are studied: i) 12-storey with CLT floor and wall system; and ii) 9-storey flat-plate CLT floor system point-supported on glulam columns. Finally, in a nonlinear pushdown analysis of a platform CLT bay to characterise the resistance mechanism of the floor and wall panels, four different alternative load-paths are evaluated. The presented findings can support the design of multi-storey CLT buildings in platform-type construction to ensure structural robustness.
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