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1.
In 2017, the Moscow municipality announced the demolition of several thousand remaining Soviet-era, standardised apartments (khrushchevki). Known as the Renovation, the renewal project promises to replace the khrushchevki with new residential districts. Based on fieldwork in Northern Izmailovo, a district targeted for demolition, this article analyses encroaching displacement by foregrounding the temporal experiences of affected residents. Building on literature that explores the political underpinnings of discourse and aesthetics in urban renewal projects, with particular attention to Rancière's temporal politics, the article contends that the Renovation depends on the discursive construction of its targets as spatial anachronisms. This renders the Soviet-era housing blocks, and those who live within them, vulnerable to a spectrum of modernising aestheticising interventions—from minor ornamentation to wholesale demolition. Based on ethnographic data, the article shows how the initial stages of redevelopment have altered a local network of benches. For a group of long-standing, elderly residents, these disruptions have instigated more profound reckonings with their own sense of time in/and space, leading to an understanding that they, too, are seen as anachronistic features of the city. Paying attention to urban materiality on a granular scale, particularly in standardised housing estates, reveals the multifaceted temporalities that inform residents' engagements with the spaces of their home districts. The article argues that doing so counters the exclusionary temporal logic of the discourse of anachronism by denying its ubiquity. In turn, it speaks to growing geographic interest in amplifying alternative temporalities in the face of destructive, terminal change.  相似文献   
2.
A simplified model useful for assessing economic losses due to moderate seismicity events in urban areas has been developed by studying the behavior of buildings before yielding their structural system, allowing for nonuniform stiffness along their height. In particular, buildings are modeled as cantilever shear beams with uniform mass and parabolic reduction of lateral stiffness. This particular stiffness distribution is relevant, as it could be expected to occur in buildings where earthquake action is a critical structural design criterion. The equation of motion governing the dynamic behavior of the proposed model is solved analytically, finding mode shapes in terms of first and second zero-order Legendre functions. The solution is verified by comparing it with results obtained from fine mesh finite element models. The effect of reducing the lateral stiffness is then studied in the first five modes of vibration. Results include modal periods, mode shapes, modal participation factors, and derivatives of mode shapes. In general, it is found that effects of reduction of lateral stiffness in mode shapes are moderate when the lateral stiffness in the free end is smaller than about seventy percent of the lateral stiffness at the fixed end, but become significant for larger reductions. Effects are particularly important for the derivative of the mode shapes, which could play a significant role in estimating interstory drift demands in buildings. Model usefulness is showcased by analyzing a test case where both acceleration and drift demands are assessed by considering uniform beams and beams with parabolic stiffness variation, finding notable improvements by considering the latter.  相似文献   
3.
Shape memory alloys (SMA) can substantially improve the damping capacity and re-centering capability of elastomeric isolators. The objective of this study is to assess the seismic performance of smart lead rubber bearings (LRBs) equipped with double cross ferrous SMA wires. Hysteretic shear response of SMA wire-based LRB is determined using finite element method. The seismic response of a multispan continuous steel girder bridge isolated by SMA-LRB is evaluated. Hybrid SMA-LRB bearing exhibits a significantly lower shear strain demand (up to 46% reduction) and a higher energy dissipation capacity (up to 31% increase) compared to the LRB.  相似文献   
4.
In this article, a collaborative structure analysis (CSA) system is developed for integrating different finite-element simulation programs. In this system, a simulated structure is divided into multiple substructures, and the interaction between the substructures is considered. Interfaces for the commercial finite-element program ABAQUS and for an open-source framework for structure analysis, OpenSees, are developed to achieve CSA integration. The CSA system is applied to analysis of a soil-structure interaction (SSI) problem, and the effects of SSI are investigated, and the efficiency and accuracy of the system are demonstrated.  相似文献   
5.
A simple mathematical expression is proposed to estimate spectra reduction damping factors for seismic design of systems with viscous dampers. The expression is obtained from the ratios between ordinates of uniform hazard spectra associated with two different return intervals (50 and 125 years), corresponding to sites with different types of soil within the Valley of Mexico. The expression proposed depends on the dominant period of the soil, and on both the vibration period and damping ratio of the structural system. Values of the damping factors proposed here are comparable to those recommended by different authors and seismic design building codes.  相似文献   
6.
Contested migration and settler politics in Cyprus   总被引:1,自引:0,他引:1  
Immigration and settler literatures provide contrasting approaches to the evaluation of conflict between ‘newcomers’ and ‘indigenous’ groups. On the one hand, immigration studies emphasize that newcomers, particularly migrants, almost never fight civil wars; on the other hand, studies on settlers in contested territories expect inherently unstable relations between settlers and native populations affected by colonization projects. While each provides strong evidence to support its argument, neither literature has adequately accounted for hybrid cases where the settler and migrant categories have become almost indistinguishable. The article focuses on Cyprus as a paradigmatic such case. Specifically, it looks at populations transferred from Turkey to the northern part of the island after 1974 described either as settlers or immigrants by rival accounts in the Cypriot conflict. While colonization constitutes a violation of international conventions and a major obstacle to peace, settlers in such places as Cyprus, Tibet or Western Sahara often meet the profile of migrant populations more interested in daily survival issues than in territorial politics. In contrast to other historical or contemporary cases of settler colonialism such as Algeria (France) or West Bank and Gaza (Israel), what is particularly puzzling in Cyprus and elsewhere is the absence of mobilization and politicization among settlers despite perceived discrimination and fear of relocation following a negotiated peace agreement. Addressing this puzzle is essential to bridging the gaps between immigration and settler literatures and in mediating the tensions between conflicting claims over space, land and the political geography of peace settlements in deeply divided societies.  相似文献   
7.
A seismic design procedure that does not take into account the maximum and cumulative plastic deformation demands that a structure will likely undergo during severe ground motion could lead to unreliable performance. Damage models that quantify the severity of repeated plastic cycling through plastic energy are simple tools that can be used for practical seismic design. The concept of constant cumulative ductility strength spectra, developed from one such model, is a useful tool for performance-based seismic design. Particularly, constant cumulative ductility strength spectra can be used to identify cases in which low-cycle fatigue may become a design issue, and provides quantitative means to estimate the design lateral strength that should be provided to a structure to adequately control its cumulative plastic deformation demands during seismic response. Design expressions can be offered to estimate the strength reduction factors associated to the practical use of constant cumulative ductility strength spectra.  相似文献   
8.
It is still a serious challenge for structural engineers to effectively reduce the seismic responses of tall and super tall buildings to further improve these structural safeties. In order to solve this problem, in this article a new kind of structural configuration, named passive mega-sub controlled structure (PMSCS), is presented, which is constructed by applying the structural control principle into structural configuration itself, to form a new structure with obvious response self-control ability, instead of employing the conventional method. In the analysis of PMSCS the equations of motion of the seismically excited system are developed, based on a realistic analytical model of the complete mega-structural system. Expressions of the displacement and acceleration response of the structure, resulting from simulated earthquake ground motions represented by stationary and nonstationary random processes, are derived. These responses are then determined for both the PMSCS and its conventional mega-sub structure (MSS) counterpart, whose configuration was modeled after the traditional mega-frame that was used in the construction of the Tokyo City Hall. A parametric study of the structural characteristics that influence the response control effectiveness of the PMSCS is presented and discussed. The region over which these structural characteristics yield the optimum seismic response control of the PMSCS is identified and serves as a very useful design tool for practitioners. The study illustrates that the proposed PMSCS offers an effective means of controlling the seismic displacement and acceleration response of tall/super-tall mega-systems. It also overcomes shortcomings exhibited in earlier proposed mega-sub controlled structural configurations.  相似文献   
9.
Acceleration response of simple yielding structure is proportional to its own weight, but it is limited by yield strength. Thus, using rocking columns that reduces global yield strength, a limited acceleration is achieved. However, the displacement becomes large due to lower strength and higher inelasticity, but it can be controlled by adding damping. Performing fragility analyses, the seismic response of R/C frame structures with rocking columns and viscous dampers is investigated. Near field MCEER ground motions are considered. The analyses show that the story accelerations are reduced by using rocking columns, while the story displacements are controlled by using viscous dampers.  相似文献   
10.
Numerical site response analyses were carried out on the Nicastro ridge in Southern Italy in order to investigate topographic effects. First, the analyses were carried out on a simplified model by employing simple artificial signals, in order to get preliminary physical insights into the two-dimensional phenomena involved. Then, numerical analyses were carried out on a more realistic heterogeneous subsoil model developed on the basis of geotechnical and geophysical investigations. Real accelerograms were selected for these analyses. Particular attention was devoted to separating topographic from stratigraphic amplification. Finally, the topographic amplification factors were compared with literature data and Eurocode 8 recommendations.  相似文献   
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