Simulation of Shake Table Tests on Out-of-Plane Masonry Buildings. Part (VI): Discrete Element Approach

ABSTRACT

Although many experimental tests and numerical models are available in the literature, the numerical simulation of the seismic response of existing masonry buildings is still a challenging problem. While the nonlinear behavior of masonry structures is reasonably predictable when the out-of-plane behavior can be considered inhibited, when the in-plane and out-of-plane responses coexist and interact, simplified models seem unable to provide reliable numerical predictions. In this article, taking advantage of the experimental tests carried out in a shaking table on two masonry prototypes at LNEC, a macro-element approach is applied for the numerical simulations of their nonlinear response. The adopted approach allows simulating the nonlinear behavior of masonry structures considering the in-plane and out-of-plane responses. Since it is based on a simple mechanical scheme, explicitly oriented to representing the main failure mechanisms of masonry, its computational cost is greatly reduced with respect to rigorous solutions, namely nonlinear FEM approaches. Two modeling strategies are adopted, namely a regular mesh independent from the real texture of the prototypes and a detailed one coherent with the units disposal. The numerical results are discussed and the correlation between the nonlinear static analyses and the dynamic response is provided.     

Transition in second birth intention in a low fertility context: the case of Jiangsu,China

When China’s decades-long one-child policy was replaced by a two-child policy, the circumstances under which women intend to have a second child become of great concern. This study examines the determinants of women’s second birth intention, as well as how the intention changes over time alongside changes in other life circumstances. Using panel data from the Jiangsu Fertility Intention and Behaviour Study (JFIBS, 2007, 2010), we find that women with more economic and familial/social resources are more likely to want a second child, while women who work in non-agriculture sectors and have higher decision-making power in the family are less inclined to have a second child. We also find that a sizeable increase of family income encourages women to upwardly revise their intention towards a desire for two children. The role of policy change on Chinese women’s second birth intention is also discussed.     

A Review of the Environmental Policy Literature from 2014 to 2017 with a Closer Look at the Energy Justice Field

This review article documents and analyzes trends within the environmental policy literature published between 2014 and 2017. We find that environmental policy scholarship has recently shifted its focus from more traditional topics, such as watershed and ecosystem management, to other modern issues, such as climate change and energy. The environmental policy literature has increased in complexity and become more interdisciplinary in nature, which we illustrate with a discussion of the energy justice literature. The methodological approaches used by environmental policy scholars have also become increasingly diverse, with a notable uptick in statistical and modeling approaches. We find that some topics, such as policy failure, gender issues, and energy welfare policies are under‐explored, and certain regions within the world, such as developing countries, are less frequently studied. We encourage scholars to consider these gaps in the literature when developing future research.     

The Role of Pilot Projects in Urban Climate Change Policy Innovation

Cities are taking a leadership role in addressing global climate change and reducing greenhouse gas (GHG) emissions, but policy innovations are needed to help cities move from goals to outcomes. Pilot projects are one means by which cities are experimenting with new ways of governing and financing climate change mitigation. In this paper, we develop a framework for understanding the role of pilot projects in urban policy innovation: their emergence and rationale, and the means by which they ultimately scale up and out to reduce GHG emissions. We use this framework to evaluate a pilot project for retrofitting social housing buildings in Toronto. We find the initial pilot project helped address the challenges of pursuing deep retrofits of social housing. Scaling these lessons up to the city level required overcoming challenges to financing and coordinating a larger project; scaling out to the provincial level revealed institutional and political obstacles to pursuing the co-benefits of deep building retrofits in social housing. Bridging agents play an important role in both scaling processes. The analysis reveals the additive nature of urban policy innovation and the dynamic interplay of change agents and institutional and political context in innovation processes.     

A Micro Model of Problem Definition and Policy Choice: Issue Image,Issue Association,and Policy Support of Power Plants

Past research on problem definition and public policy primarily focuses on the macro-system level. In this study, we propose a micro model of problem definition and policy choice at the individual level. We argue that while individual citizens' problem definitions and policy preferences are rooted in and filtered through their predisposition characteristics (such as socioeconomic status, political orientation, and informational base), their policy choices also strongly depend on how they define public issues, particularly how they perceive the image of an issue at hand and how they associate the issue with other public issues. Our empirical analyses, based on data from a national public survey on energy and power plant issues, support the key propositions derived from our theoretical model. Key contributions to and implications for policy studies are discussed in conclusion.     

Tracing territorial-illicit relations: Pathways of influence and prospects for governance

Recent research increasingly illustrates that illicit economies, especially drug production and trafficking, may result in environmental destruction as well as violence and human rights abuses in remote, rural places. At the same time, the idea of titling forest lands collectively, especially to Indigenous Peoples, has emerged as a key measure to halt deforestation, protect biodiversity, and mitigate against climate change. A focus on the conditions under which titling can achieve these outcomes, specifically on governance and institutions, may underestimate the degree to which illicit activities play a major role in influencing socio-ecological and political-economic possibilities in new territories. Drawing on a review of the literature and a case study of the adjacent Miskitu Indigenous regions in Honduras and Nicaragua, we propose several potential pathways through which collective land titling may influence the functioning of illicit economies, and vice versa, and thus potential constellations of territorial governance. We identify and provide examples of five key pathways: Coexistence, Cooperation, Corruption, Competition, and Confrontation. These pathways reflect underlying political and institutional conditions within a given place and are dynamic across space and time. With the Muskitia in mind, we outline how the role of the state can significantly influence the functioning of Indigenous institutions and narco-trafficking, as well as the ways in which these two interact, troubling the scalar and spatial dimensions of “local” governance in this region and more broadly.     

The Question of "Why It Is in Henan" and the New Direction of Chinese Scientific and Technological Archaeology

The ritual institutionalization demonstrated in the bronze production at Erlitou and further developed during the Shang and Zhou periods that formed a distinctive feature of bronze civilizations. While exploring the path of the earliest state formation, we could consider why Erlitou was chosen from the unveiling of the Bronze Age in China. Much attention had been paid to archaeological, chronological, geographic, and climatic information in the existing studies, but the relationship between bronze metal resources and the formation of the Erlitou state needed more attention. Viewing the Erlitou culture as the earliest state form in China and thus exploring the path of formation of early states was a return to the original theme of archaeology.     

明清时期福州西湖水环境变迁及其治理研究

明清时期,福州西湖水环境总体趋劣。明代西湖水源较为充足,水质状况良好;万历以降,受民间占垦等社会因素影响,湖域面积缩减,水质日渐趋下;清代中后期,福州城内水道淤浅,江潮渐绝,西湖水源趋向单一。明清时期西湖水环境的变动,除了受区域气候干湿变化、山地森林水土保持以及湖泊含沙量的影响之外,还与人为的水地之争密切相关。由于人地关系紧张,加之水资源权属不清、新垦湖田税赋征收模糊等,获取湖利的必然性刺激了民间占湖为地的行为。地方官府也曾采取如修闸筑坝护堤、追返侵地还湖、清理粪秽淤泥等治理措施,并取得阶段性成效,但受区域人口、土地资源与生存环境等社会经济因素的影响,西湖历经多次治理仍积弊难除。     

Earthquake Protection of Colonial Bell Towers in Colima,Mexico with Externally Prestressed FRPs

A methodology for the seismic vulnerability reduction of old masonry towers with external prestressing is presented. It is applied at the Colonial bell-towers of the Cathedral of Colima, Mexico, characterized for being a high seismic area (M>7.5). The 3D FE models are calibrated with experimental data and assessed through nonlinear static approaches including the seismic demand and an accurate validated masonry model. Based on an extensive parametric study on different configurations of old masonry towers, it is selected an optimal prestressing force and device. The Colonial towers are retrofitted with four prestressing devices of FRPs to convert them into a high energy-dissipative reinforced masonry. The external vertical prestressing is included at key points identified in the seismic vulnerability assessment. This technique is in compliance with the demand for architectural conservation and may be located without drilling and unbounded in order to be fully removable. The seismic performance is enhanced by increasing force, displacement, and internal confinement. It is observed an upgrading of 35% and 20% of displacement capacity. With these results it is corroborated that external vertical prestressing allows a substantial increment of ductility for seismic energy dissipation purposes.     

Are Ukraine’s reforms breaking its state capture? An agenda for genuine change

Abstract

Ukraine is one of a handful of post-communist countries that has a lower Gross Domestic Product today than in 1990, according to the World Bank. The problem is that it has seen too little reform. The country has experienced three serious periods of reform, but none has been as important as the reforms of 2015. The big question is whether Ukraine has finally broken out of persistent state capture. This paper by long-lasting Ukraine-watcher Anders Åslund suggests that Ukraine has carried out greater economic reforms than ever before with the unification of energy prices, large budget cuts, floating exchange rates, halved payroll tax, and a major bank purge. Yet, the question remains whether Ukraine has really broken out of state capture and whether it will be able to turn to a steady course of high economic growth of 5–7% a year.