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91.
馆藏浮放陶瓷文物地震摇晃响应振动台试验 总被引：2，自引：2，他引：0
为保护可移动文物,采取试验方法研究了地震作用下馆藏浮放文物的摇晃响应.以故宫某展柜为原型,制作了1∶1比例的模型,并在展柜内放置了一陶瓷文物,进行了振动台试验.通过白噪声激励,获得了展柜的基频;通过输入不同类型、不同强度的地震波,研究了展柜和文物的地震响应;通过数值模拟,从理论上对模型地震响应进行了进一步论证.结果表明:对展柜而言,其基频在29～35 Hz之间,与地震波卓越频率相差较大,因而在地震作用下摇晃不明显;对文物而言,在地震波强度较小时能保持稳定振动状态,而在地震波强度较大时,文物容易产生明显摇晃并导致倾覆.此外,数值模拟结果与振动台试验结果吻合,证明了试验方法的有效性.在实际工程中,对高宽比较大的文物,应采取适当的加固措施,以减轻其摇晃震害. 相似文献
92.
In this paper, the results of recent studies on inelastic seismic response of MDOF shear-building structures are presented. In the last few decades, the concept of response modification factor R has been introduced and developed to account for inelastic nonlinear behaviour of structures under earthquakes. In this paper, an attempt has been made to adjust and extend this concept through introducing a modifying factor R T . This factor is used for dynamic analysis of MDOF structures, including the calculation of inelastic response spectra. Sensitivity analysis was carried out to identify the parameters that have influence on R T . It has been demonstrated that R T is predominantly a function of number of stories, and accordingly a relationship has been suggested. Finally, an approximate approach has been developed for evaluating the seismic strength and ductility demands of MDOF structures. 相似文献
93.
The three dimensional pounding phenomenon of two adjacent buildings during earthquakes with aligned rigid horizontal diaphragms is investigated for the linear and nonlinear structural response. The developed formulation takes into account three dimensional dynamic contact conditions for the velocities and accelerations based on the impulse-momentum relationship, using the coefficient of restitution e and the ratio μ, of tangential to normal impulses, which corresponds to the coefficient of friction under certain conditions. The contact points are determined geometrically from the displacements of the diaphragms' centre of mass. The results of the proposed formulation are compared with those obtained with the Lagrange multipliers approach. Test results are performed for two sets of multi-storey adjacent buildings subjected to real earth-quake motions with elastic and inelastic structural response. 相似文献
94.
Shaw Badenhorst 《Environmental Archaeology》2015,20(1):41-51
Domestic faunal samples from farming sites from southern Africa dating from the Early (～AD 200–900) and Middle (～AD 900–1300) Iron Ages with large faunal samples are typically dominated by sheep/goats (both number of identified specimens and minimum number of individuals for large samples). However, four exceptions to this general pattern from these time periods are Bosutswe, Nqoma (both in Botswana), KwaGandaganda and Mamba (both in KwaZulu-Natal). At these sites, cattle outnumber sheep/goats, which have previously been measured using a Cattle Index. Intensive hunting is investigated at one of these sites, Bosutswe. Using various lines of evidence, including measuring high- vs. low-ranked prey, economic activities, as well as grease extraction and ageing from the most common taxon, plains zebra (Equus quagga), it is suggested that resource depression of wild game likely occurred. This would fit the expectation, based on human behavioural ecology, that as high-ranked game resource diminished over time, more emphasis was placed on cattle herding. The greater emphasis could have influenced descent patterns of people at Bosutswe. By the Late Iron Age (～AD 1300–1820s), cattle dominate most faunal assemblages in southern Africa with large sample sizes, and ethnographic and historical information confirm the central role these animals played in the social, political and economic lives of these farmers. 相似文献
95.
AbstractThis article gives insights into an inter- and transdisciplinary research approach designed to enhance the planning of climate change adaptation responses at urban-regional level. What makes interdisciplinary approaches to adaptation action unique is its ability to unravel the complexity of climate change and the interwoven processes it entails. It is the planning aspect here that makes stakeholder involvement crucial. Hence in contemporary climate change research the science-policy interface takes centre stage, generating response capacity and exchanging ‘usable’ information with decision-makers within the framework of a transdisciplinary approach. Climate action plans and climate adaptation strategies, for example, have the potential to unite sectors and levels of decision-making around an integrated planning approach. This article discusses the challenges and constraints of the inter- and transdisciplinary research approach developed for a Metropolitan Region of Santiago de Chile (MRS). 相似文献
96.
Xicheng Zhang Chenwei Wu Jianyang Xue Hui Ma 《International Journal of Architectural Heritage》2020,14(8):1252-1268
ABSTRACT This article presents a study of the applicability of fast nonlinear analytical (FNA) models in predicting the global response of Chinese traditional timber-frame building with Dou-Gon under seismic excitation. Efforts are made to overcome challenges in establishing simplified calculation models, and the corresponding dynamic equations are derived considering the mechanical behavior of sliding column root, mortise-tenon joint and Dou-Gon (bracket sets). Furthermore, nonlinear time-history analysis is conducted under different seismic excitations. Through a verification study, a good correspondence is obtained with previous shake-table test results. Seismic response analysis is also conducted to investigate the energy dissipation of column root sliding, mortise-tenon joint, and Dou-Gon. Subsequently, peak responses of column root and roof under increased values of peak ground acceleration (PGA) are also analyzed. And then, seismic isolation ability and damping characteristics of the model are discussed. 相似文献
97.
High levels of survey nonresponse potentially produce unreliable data due to the often indeterminable possibility of such data being subject to nonresponse bias. In this paper, spatial patterns of global nonresponse rate are analyzed in order to identify whether systemic bias exists across urban spaces with regard to survey nonresponse. Forward stepwise regression is used in combination with spatial regression analysis to build models enabling the prediction of global nonresponse rates in the voluntary 2011 National Household Survey based on explanatory employment, housing, income, and other variables within 11 Canadian cities. The modelling process underscores the inequity of global nonresponse rates; places with high unemployment, high rates of rental properties, a higher proportion of Aboriginal residents, and lower educational attainment have lower compliance with the voluntary survey. Such a pattern has the potential to dramatically influence the ability of government, non-governmental organizations, and other service providers to address the needs of residents of such urban areas. 相似文献
98.
T. PAULAY 《Journal of Earthquake Engineering》2013,17(4):721-745
With a distinct design rather than analysis-oriented approach, some torsional phenomena, arising during the elasto-plastic seismic response of building structures, are addressed. It is postulated that existing code recommendations, expressed only in terms of the properties of elastic structures, are largely irrelevant when the design needs to be based on ductile system behaviour. Torsional restraint provided by elastic elements of a system, is claimed to be the desirable property controlling the amplification of inelastic translatory deformations of critical elements by storey twist. With the identification of the sources of inelastic element deformations, a simple behaviour-based design strategy is proposed. This should ensure that the displacement ductility demand, expected to be imposed on the system, does not result in deformations that, as a consequence of storey twist, may exceed the displacement ductility capacity of critical elements. 相似文献
99.
《Political Theology》2013,14(3):537-557
AbstractIn the past decade social theorists and Continental philosophers have returned again to an engagement with Christianity and the legacy of Christian belief. This is framed in the context of a Europe seen in transition to a post-secular identity and, often implicitly, against what is seen as an encroaching Islamic presence within Europe. This move has often brought together Marxist, post-Marxist, and Catholic-legacy philosophers, together with philosophical Protestants in an attempt to recover what I term a political theology of response. Response, in opposition to belief, signals an alternative post-secular turn of attempted inclusion out of a perceived shared cultural legacy. This essay asks if, in such a cultural-philosophical turn, the alternative post-secular turn of a political theology of response signals that belief remains within the private sphere as we seek to engage in a public conversation of non-believing "response"? 相似文献
100.
Behavioural approaches have become mainstream in economics,supported by the research of cognitive scientists and psychologists,yet their findings have attracted little attention from geographers.This article argues for a renewed behavioural economic geographythat builds on research in behavioural economics but also addressesone of its main shortcomings: a lack of engagement with thesocial context of decision-making. I outline a research agendathat bridges the gap between the disciplines in the area ofpension decision-making, using the example of choice in UK occupationalplans to argue for a mixed methodological approach to meet thechallenge of taking context seriously. 相似文献