The recent Canterbury earthquake sequence in 2010-2011 highlighted a uniquely severelevel of structural damage to modern buildings, while confirming the high vulnerability andlife threatening of unreinforced masonry and inadequately detailed reinforced concretebuildings. Although the level of damage of most buildings met the expected life-safety andcollapse prevention criteria, the structural damage to those building was beyond economicrepair. The difficulty in the post-event assessment of a concrete or steel structure and theuneconomical repairing costs are the big drivers of the adoption of low damage design.Among several low-damage technologies, post-tensioned rocking systems were developed inthe 1990s with applications to precast concrete members and later extended to structural steelmembers. More recently the technology was extended to timber buildings (Pres-Lamsystem).This doctoral dissertation focuses on the experimental investigation and analytical andnumerical prediction of the lateral load response of dissipative post-tensioned rocking timberwall systems.The first experimental stages of this research consisted of component testing on both externalreplaceable devices and internal bars. The component testing was aimed to furtherinvestigate the response of these devices and to provide significant design parameters.Post-tensioned wall subassembly testing was then carried out. Firstly, quasi-static cyclictesting of two-thirds scale post-tensioned single wall specimens with several reinforcementlayouts was carried out.Then, an alternative wall configuration to limit displacement incompatibilities in thediaphragm was developed and tested. The system consisted of a Column-Wall-Columnconfiguration, where the boundary columns can provide the support to the diaphragm withminimal uplifting and also provide dissipation through the coupling to the post-tensionedwall panel with dissipation devices.Both single wall and column-wall-column specimens were subjected to drifts up to 2%showing excellent performance, limiting the damage to the dissipating devices. One of theobjectives of the experimental program was to assess the influence of construction detailing,and the dissipater connection in particular proved to have a significant influence on thewall’s response.The experimental programs on dissipaters and wall subassemblies provided exhaustive datafor the validation and refinement of current analytical and numerical models.The current moment-rotation iterative procedure was refined accounting for detailedresponse parameters identified in the initial experimental stage. The refined analytical modelproved capable of fitting the experimental result with good accuracy.A further stage in this research was the validation and refinement of numerical modellingapproaches, which consisted in rotational spring and multi-spring models. Both themodelling approaches were calibrated versus the experimental results on post-tensionedwalls subassemblies. In particular, the multi-spring model was further refined andimplemented in OpenSEES to account for the full range of behavioural aspects of thesystems.The multi-spring model was used in the final part of the dissertation to validate and refinecurrent lateral force design procedures.Firstly, seismic performance factors in accordance to a Force-Based Design procedure weredeveloped in accordance to the FEMA P-695 procedure through extensive numericalanalyses. This procedure aims to determine the seismic reduction factor and over-strengthfactor accounting for the collapse probability of the building. The outcomes of this numericalanalysis were also extended to other significant design codes.Alternatively, Displacement-Based Design can be used for the determination of the lateralload demand on a post-tensioned multi-storey timber building. The current DBD procedurewas used for the development of a further numerical analysis which aimed to validate theprocedure and identify the necessary refinements.It was concluded that the analytical and numerical models developed throughout thisdissertation provided comprehensive and accurate tools for the determination of the lateralload response of post-tensioned wall systems, also allowing the provision of designparameters in accordance to the current standards and lateral force design procedures.
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