Dynamic-MFA examination of Chilean housing stock: long-term changes and earthquake damage

The dynamics and metabolism of the built environment are important for understanding the construction, renovation and demolition activities that characterize its long-term physical development. Previous research on building stock development is limited, particularly for developing countries. As one of the most seismically active countries in the world, Chile's built environment is constantly subjected to losses. This study included earthquake vulnerability and damage in a dynamic material flow analysis (MFA) of the Chilean housing stock. Stock and flows of residential floor area were modelled using population and life style parameters. Demolition was modelled assuming a constant demolition rate. By characterizing the building stock according to vulnerability classes and establishing a mass balance per class, the effects of different typology distributions on the overall damage to the stock caused by earthquakes could be assessed. Scenarios with different trends in typology distribution for new construction and renovation suggest that significant potential exists for reducing future earthquake damage in the Chilean housing stock. This is best achieved by gradually reducing the vulnerability of buildings to earthquakes. Legislation, building standards and financial instruments could be used to ensure such reductions in earthquake damage and thereby provide socio-economic benefits in the future.     

村镇防灾减灾规划研究

为保障村镇一体化进程中村镇的防灾安全,本文从灾害系统论和风险管理角度出发,剖析了我国村镇灾害的特征,探讨了村镇防灾减灾的基本对策,提出了村镇防灾减灾规划建设思路。     

十天高速汉中西段高填方边坡类型及特征

本文依托十天高速公路汉中西段沿线高填方边坡病害治理工程,归纳总结了该高速公路沿线的环境因素、基本地质条件和边坡特征,分析了高填方边坡病害类型及失稳破坏模式,并针对不同类型病害体的发生发展机理和变形原因,开展了相应的防治工程措施的研究,为今后山区高速公路建设中高填方边坡病害预防和治理提供借鉴。     

巨厚火成岩下采动覆岩应力场-裂隙场耦合演化机制

针对杨柳煤矿主采10煤层诱导上覆巨厚火成岩运移破断引发剧烈地表沉陷、瓦斯喷井以及工作面压架等动力灾害的难题,基于巨厚火成岩破断特征,采用物理模拟、数值模拟与理论分析相结合的方法研究了巨厚火成岩下覆岩裂隙发育规律与采动应力分布规律,得到火成岩破断前后裂隙发育高度、支承压力峰值和应力集中区最大高度等指标随工作面推进的变化特征,从而揭示了巨厚火成岩下采动应力场-裂隙场耦合演化致灾机制,即煤层采动→应力重新分布→应力集中→裂隙发育→覆岩破断→应力转移→裂隙扩展→"弧形"离层→火成岩破断→动力灾害。从控制应力集中与裂隙发育两方面提出了"采空区充填技术—离层注浆充填技术—保护层开采技术"的防灾技术体系。     

Disaster Recovery Among Multiethnic Immigrants: A Case Study of Southeast Asians in Bayou La Batre (AL) After Hurricane Katrina

Problem, research strategy, and findings: Immigrants suffer disproportionately from disasters because they have limited capacity to prepare for, respond to, or recover from a disaster. Unfortunately, planners and emergency managers are often inadequately trained or educated about the unique sociocultural needs and assets among immigrant groups. Hurricane Katrina exposed challenges to long-term recovery among Southeast Asian immigrants in Bayou La Batre (AL). We employ qualitative research methods, including in-depth interviews, focus groups with immigrants, and site visits, to better understand the barriers to disaster recovery and to inform local, state, federal, and nongovernmental agencies on how to better prepare disaster plans that would improve disaster recovery for multiethnic, multicultural, immigrant populations. We find four significant categories of sociocultural barriers to disaster recovery for Southeast Asian immigrants in Bayou La Batre: 1) language, literacy, and communication; 2) cultural differences in help-seeking; 3) inability to navigate the disaster recovery bureaucracy; and 4) and lack of leadership. Despite these barriers to recovery, immigrant groups can also teach us about resiliency in the face of disaster. The levels of trust, cooperation, and collaboration within the ethnic immigrant community help to buffer the damaging effects during the response and recovery period.

Takeaway for practice: Our study reveals that cultural competency among staff members engaged in preparedness, response, and recovery is essential for an effective disaster recovery process. Furthermore, engaging immigrant groups in long-term recovery requires trust and relationship building prior to a disaster. In doing so, more culturally appropriate and effective disaster recovery plans can be developed.     

中国海绵城市——一座巨型绿色屋顶实验室

绿色屋顶是雨洪管理中一项重要的低影响开发（LID）措施。由于气候变化和城市快速发展,LID雨洪管理策略对于当下全球的城市设计都至关重要,尤其是在经济蓬勃发展历来又饱受洪水灾害的中国。气候变化导致降水事件及雨水径流峰值流速难以准确预测。面对建筑布局日益稠密、不透水下垫面日益增多的中国城市,设计师们需要随时做好应对城市雨洪问题的准备。2015年提出的“海绵城市”战略为在城市尺度下应用和监测绿色屋顶效益提供了机会。目前业内大多数国际性绿色屋顶的研究应用都局限于小型控制实验区,借海绵城市建设之东风有机会将应用实验扩展到城市规模。中国雨洪管理智慧的历史可以追溯至5 000年前,现今中国正处于成为大尺度绿色屋顶实践世界领先者的机遇期。因此,LID应是城市设计的驱动力量而非事后补救措施。景观设计师不仅能够从场地、城市和区域3个层面上对场地及其周围环境进行全面解读,而且对需要实施LID的其他因素也有全面认知。为探究中国雨洪管理结构提供了新的视角,对景观设计师如何参与LID实践提出了建议。     

福州海峡国际会展中心结构健康监测必要性探讨

本文介绍国内外结构健康监测研究状况,结合福州海峡国际会展中心在省内重要性,探讨了对中心进行结构健康监测科研意义和工程实践的必要性。     

The importance of gully flow modelling to urban flood simulation

ABSTRACT

Urban flood simulation often ignores or simplifies the function of underground gully systems due to data and computational limitations. To discover the influence of gullies on urban flooding, a novel approach is proposed in this study, by fully-coupling a 1D gully flow model (GFM), a 1D sewer flow model (SFM), and a 2D overland flow model (OFM) to simultaneously simulate the flow exchanges between surface, gullies and sewer pipes. This fully-coupled approach is compared with a simplified approach which directly introduces surface water into sewer pipes without being via gullies. The validation results show that the fully-coupled approach considerably reduces the underestimation of flood extent by 27% compared with the simplified approach. Without considering the capacity of lateral tubes between gullies and sewer pipes, the simplified approach over-drains the surface water into sewer pipes. The modelling of gully flow is crucial for correctly evaluating the efficiency of drainage systems.     

A flood risk assessment to municipal infrastructure due to changing climate part II: case study

Flooding often has devastating consequences. It is important to understand the evolution of these risks as climate changes. Municipal infrastructure is designed using historical data that no longer accurately represents current climate conditions, indicating infrastructure may underperform. The purpose of this study is to apply a new methodology for the assessment of climate change caused flood risk by Bowering et al. (2013) to the City of London, Ontario, Canada. Floodplain maps derived from climate, hydrologic and hydraulic analyses provide direct input into risk assessment procedure. Inundated infrastructure and high risk areas are identified in tables and maps for two climate and two hydraulic scenarios. Results indicate the most critical flood scenario is the 100 year climate change upper bound and high risk is driven by expensive infrastructure located in the floodplains. Results of the study are used as the support for climate change adaptation policy development and emergency management.     

On pre-filling probability of flood control detention facilities

Flood control detention facilities are widely used for stormwater control in urban areas. Standard design procedures are in most cases based on the design storm approach: a single flood event at a time is considered, at the beginning of which the facility is assumed completely empty. The possibility of pre-filling from previous events is then neglected and underestimation of storage volume may occur. In this paper an analytical probabilistic approach to estimate the probability of pre-filling is presented and its effects, due to outflow rate and storage volume, are investigated. Two different strategies for the outlet control are analysed. Results are validated on a case study.