中国妇女发展脆弱性：测度、时空演化及驱动机制

借鉴人类发展指数（HDI）,从健康、教育及就业三大维度构建中国妇女发展脆弱性评估模型。以妇女发展脆弱性指数为测度指标,运用变异系数、LISA时间路径和时空跃迁等方法,对2006—2016年中国妇女发展状况的区域差异、空间分布和时空交互特征进行分析,并利用计量经济学模型探讨其影响机制。结果表明：①2006—2016年,中国妇女发展脆弱性总体上呈下降趋势,区域差异在波动中逐渐扩大。在区域尺度上,东部地区较低,中部和东北地区次之,西部地区最高。东部地区内部差异显著,呈现两极化;②脆弱性类型以低和较低脆弱类型为主,大致以“胡焕庸线”为界,西北半壁妇女发展脆弱性显著偏高;③中国妇女发展脆弱性空间分布具有较强的稳定性,存在一定的路径依赖和空间锁定特征。相对长度由东部沿海向西北内陆及西南地区递增,弯曲度表现出相似的空间分异特征;④妇女发展脆弱性是多因素交互作用的结果。经济发展水平、城镇化、全球化和教育事业发展对于降低妇女发展脆弱性具有积极作用。政府行为的驱动效应对脆弱性存在抑制作用,但未通过显著性检验。     

Ways In and Out of Vulnerability to Climate Change: Abandoning the Mubarak Project in the Northern Nile Delta,Egypt

Abstract: Climate change is already exerting significant pressure on humanity, but some people have the resources to cope, while others do not. What, then, determines vulnerability to climate change? This article presents a case study of one site of vulnerability in Egypt, known as the Mubarak Project villages on the shores of the Mediterranean. The soil of these villages is now undergoing rapid salinization, forcing farmers to apply sand to “elevate” their fields above the rising salty water table—but not all farmers can afford to buy the requisite sand. Accumulation by dispossession under the Mubarak regime has pushed some people towards the frontline of climate change, while at the same time denying them the resources to stay there. Using our case, we explore the connection between accumulation by dispossession and vulnerability to climate change and ask if an end to the former could reduce the latter in Egypt.     

SEISMIC BEHAVIOUR OF PERIMETER AND SPATIAL STEEL FRAMES

The present study deals with the seismic performance of partial perimeter and spatial moment resisting frames (MRFs) for low-to-medium rise buildings. It seeks to establish perimeter configuration systems and hence the lack of redundancy can detrimentally affect the seismic response of framed buildings. The paper tackles this key issue by com-paring the performance of a set of perimeter and spatial MRFs, which were “consistently designed”. The starting point is the set of low-(three-storey) and medium-rise (nine-storey) perimeter frames designed within the SAC Steel Project for the Los Angeles, Seattle and Boston seismic zones. Extensive design analyses (static and multi-modal) of the perimeter frame buildings and consistent design of spatial frame systems, as an alternative to the perimeter configuration, were conducted within this analytical study. The objectives of the consistent design are two-fold, i.e. obtaining fundamental periods similar to those of the perimeter frames, i.e. same lateral stiffness under design horizon-tal loads, and supplying similar yield strength. The seismic behaviour of perimeter and spatial configuration structures was evaluated by means of push-over non-linear static analyses and inelastic dynamic analyses (non linear time histories). Comparisons be-tween analysis results were developed in a well defined framework since a clear scheme to define and evaluate relevant limit states is suggested. The failure modes, either local or global, were computed and correlated to design choices, particularly those concerning the strength requirements (column overstrength factors) and stiffness (elastic stability indexes). The inelastic response exhibited by the sample MRFs under severe ground motions was assessed in a detailed fashion. Conclusions are drawn in terms of local and global performance, namely global and inter-storey drifts, beam and column plas-tic rotations, hysteretic energy. The finding is that the seismic response of perimeter and spatial MRFs is fairly similar. Therefore, an equivalent behaviour between the two configurations can be obtained if the design is “consistent”.     

A DAMAGE MODEL FOR THE ANALYSIS OF THE SEISMIC RESPONSE OF MONUMENTAL BUILDINGS

In this paper the Author proposes a damage model for the analysis of masonry plates and shells, which is based on an improvement of a previous constitutive model. The modifications introduced, connected to the head joint damage, allow us to study the influence of masonry texture on the damage modes once the mechanical characteristics of the elements constituting the masonry and the results of tests on simple assemblages are known. Having a nonlinear constitutive model is certainly one of the basic elements for understanding the damage mechanisms in masonry buildings. If, in fact, an elastic-linear constitutive model may be used under normal loading conditions, in critical situations it is necessary to model the damage and the dissipation mechanisms that occur between the elements, stone (brick) and mortar, in correlation with their characteristics and kind of masonry. To validate the model a comparison is made between the numerical and experimental results, in the case of tests available in the literature in masonry panels subjected to out-of plane loading and in a real structure through the observation of the damage in Umbria (Italy) surveyed after the 1997 earthquake.     

Design Methodology for Seismic Upgrading of Substandard Reinforced Concrete Structures

This article presents a design methodology for seismic upgrading of existing reinforced concrete (RC) buildings. The methodology is based on the modification of the deflected shape of the structure so as to achieve a near-uniform distribution of interstorey drift along the building height, thereby eliminating damage localization. Yield Point Spectra are utilized for the definition of demand and a direct displacement-based design approach is implemented. The fundamental steps of the method are described in detail, including a systematic evaluation of assumptions and limitations. A full-scale tested structure is used as a case study for assessment and verification of the proposed methodology. Alternative retrofit scenarios are set according to target response and performance levels. The role of the target deflected response shape and its influence on the outcome of the retrofit strategy is investigated. The viability of the alternative retrofit scenarios is studied for different ground motions including near-fault earthquake records.     

A Fast and Efficient Simulation of the Far-Fault and Near-Fault Earthquake Ground Motions Associated with the June 17 and 21, 2000, Earthquakes in South Iceland

The two M_w 6.5 earthquakes on June 17 and 21, 2000, respectively, in the populated South Iceland Seismic Zone (SISZ) significantly augmented the Icelandic database of strong ground motions, and several strong velocity pulses were recorded at near-fault sites. The strong motions are interpreted via the Specific Barrier Model (SBM) and a mathematical model of near-fault velocity pulses. The data indicates self-similar source scaling and significantly greater attenuation of seismic waves than in other interplate regions. Through inversion of the data a new attenuation function for the SISZ has been adopted, which results in unbiased simulations. For the first time, the characteristics of the recorded near-fault pulses have been identified and compared to the worldwide database of such records. The SBM and the near-fault pulse model combine naturally in a fast and efficient synthesis of realistic, broad-band strong ground motions in the far-fault and near-fault region. Such simulations are showcased for the June 2000 earthquakes and indicate that the modeling approach adopted in this study is an effective tool for the estimation of realistic earthquake ground motions in the SISZ.     

Equivalent Damping in Support of Direct Displacement-Based Design

The concept of equivalent linearization of nonlinear system response as applied to direct displacement-based design is evaluated. Until now, Jacobsen's equivalent damping approach combined with the secant stiffness method has been adopted for the linearization process in direct displacement-based design. Four types of hysteretic models and a catalog of 100 ground motion records were considered. The evaluation process revealed significant errors in approximating maximum inelastic displacements due to overestimation of the equivalent damping values in the intermediate to long period range. Conversely, underestimation of the equivalent damping led to overestimation of displacements in the short period range, in particular for effective periods less than 0.4 seconds. The scatter in the results ranged between 20% and 40% as a function of ductility. New equivalent damping relations for four structural systems, based upon nonlinear system ductility and maximum displacement, are proposed. The accuracy of the new equivalent damping relations is assessed, yielding a significant reduction of the error in predicting inelastic displacements. Minimal improvement in the scatter of the results was achieved, however. While many significant studies have been conducted on equivalent damping over the last 40 years, this study has the following specific aims: (1) identify the scatter associated with Jacobsen's equivalent damping combined with the secant stiffness as utilized in Direct Displacement-Based Design; and (2) improve the accuracy of the Direct Displacement-Based Design approach by providing alternative equivalent damping expressions.     

VULNERABILITY OF ELASTOMERIC BEARING ISOLATED BUILDINGS AND THEIR EQUIPMENT

In this paper, we compare the vulnerability of isolated and conventional structures as well as equipment when uncertainty on the excitation and on some of the structural properties is considered. This comparison is performed, mainly, with a series of Monte Carlo simulations. The results clearly show the higher sensitivity of isolated structures and their equipment when submitted to statistically reasonable excitations that are different from those used for their design. This fact is recognised by some, but not all, earthquake regulations, mainly, by considering lower behaviour factors for isolated structures than for conventional ones. Although isolated structures designed according to these recommendations (e.g. FEMA 368) exhibit tow damage less frequently than conventional structures, the probability of failure is similar for both types of structure.     

Behavior Factor for Performance-Based Seismic Design of Plane Steel Moment Resisting Frames

Simplified expressions to estimate the behavior factor of plane steel moment resisting frames are proposed, based on statistical analysis of the results of thousands of nonlinear dynamic analyses. The influence on this factor of specific structural parameters, such as the number of stories, the number of bays, and the capacity design factor of a steel frame, is studied in detail. The proposed factor describes the seismic strength requirements in order to restrict maximum storey ductility to a predefined value. Interrelation studies between maximum storey ductility and the Park-Ang damage index are also provided for the damage-based interpretation of the performance levels under consideration. Realistic design examples serve to demonstrate the ability of the proposed factor to convert conventional force-based design to a direct performance-based seismic design procedure.     

贫困山区旅游地社会—生态系统脆弱性及影响机理

借助社会—生态系统理论与脆弱性分析框架,以恩施州为例,从敏感性与适应性两方面构建评价指标体系,对旅游地社会—生态系统脆弱性进行定量测度,运用地理探测器方法探测脆弱性分异的风险因子与影响机理.结果表明:①研究区脆弱性水平整体处于中等水平,抵御内外部风险的能力仍显不足;②村域脆弱性主要为中、低等脆弱性,各村敏感性与适应性构...