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Coupling beams between shear walls are one of the key elements for energy dissipation in tall buildings. A representative mathematical model of coupling beam should represent flexure, shear and interface slip/extension mechanisms simultaneously. This goal can be achieved by using either detailed finite element models or by using macro models. This paper presents a review of various macro model alternatives for diagonally reinforced coupling beams in the literature. Three distinct methods have been reviewed in terms of their modeling techniques, the cyclic response overlap and the amount of cumulative plastic energy dissipated based on the results of previously performed tests. Through an analytical study, adequately accurate results can be captured by using macro models, although they are simpler in practice compared to sophisticated micro models. This study shows that, by modifying ultimate shear capacities where concrete material between diagonal bundles is adequately confined, it is possible to capture a more realistic result and a better approximation to the actual responses. It is also concluded that a simpler numerical model for diagonally reinforced coupling beams can be achieved by introducing linear part of slip/extension behavior into elastic part of the beam. It is observed, as a result of this study, that the ratio of effective stiffness to that of the gross cross-sectional one ranges from 0.04 to 0.14 in diagonally reinforced coupling beams depending on the aspect ratio and the beam strength parameters.
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During the 2015 Gorkha earthquake of 7.8 Mw that hit Kathmandu Valley, Nepal, numerous Nepalese Pagodas suffered extensive damage while others collapsed. Risk reduction strategies implemented in the region focused on disassembling historical structures and rebuilding them with modern material without in depth analysis of why they suffer damage and collapse. The aim of this paper is to evaluate the effectiveness of low-cost, low-intervention, reversible repair and strengthening options for the Nepalese Pagodas. As a case study, the Jaisedewal Temple, typical example of the Nepalese architectural style, was investigated. A nonlinear three-dimensional finite element model of the Jaisedewal Temple was developed and the seismic performance of the temple was assessed by undertaking linear, nonlinear static and nonlinear dynamic analyses. Also, different structural intervention options, suggested by local engineers and architects working in the restoration of temples in Nepal, were examined for their efficacy to withstand strong earthquake vibrations. Additionally, the seismic response of the exposed foundation that the Nepalese Pagodas are sitting on was investigated. From the results analysis, it was found that pushover analysis failed to capture the type of failure which highlights the necessity to perform time-history analysis to accurately evaluate the seismic response of the investigated temple. Also, stiffening the connections along the temple was found to enhance the seismic behaviour of the temple, while strengthening the plinth base was concluded to be insignificant. Outputs from this research could contribute towards the strategic planning and conservation of multi-tiered temples across Nepal and reduce their risk to future earthquake damage without seriously affecting their beautiful architectural heritage.
Communities worldwide are critically re-examining their seasonal cultures and calendars. As cultural frameworks, seasons have long patterned community life and provided repertoires for living by annual rhythms. In a chaotic world, the seasons - winter, the monsoon and so on - can feel like stable cultural landmarks for reckoning time and orienting our communities. Seasons are rooted in our pasts and reproduced in our present. They act as schemes for synchronising community activities and professional practices, and as symbol systems for interpreting what happens in the world. But on closer inspection, seasons can be unstable and unreliable. Their meanings can change over time. Seasonal cultures evolve with environments and communities’ worldviews, values, technologies and practices, affecting how people perceive seasonal patterns and behave accordingly. Calendars are contested, especially now. Communities today find themselves in a moment of accelerated and intersecting changes - from climate to social, political, and technological - that are destabilizing seasonal cultures. How they reorient themselves to shifting patterns may affect whether seasonal rhythms serve as resources, or lead people down maladaptive pathways. A focus on seasonal cultures builds on multi-disciplinary work. The social sciences, from anthropology to sociology, have long studied how seasons order people’s sense of time, social life, relationship to the environment, and politics. In the humanities, seasons play an important role in literature, art, archaeology and history. This book advances scholarship in these fields, and enriches it with extrascientific insights from practice, to open up exiting new directions in climate adaptation. Critically questions traditional, often-static notions of seasons; re-interpreting them as more flexible, cultural frameworks adapting to changes to our societies and environments.
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