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1.
Olga Filippova Yu Xiao Michael Rehm Jason Ingham 《Building Research & Information》2018,46(7):711-724
The marked increase in the awareness of earthquake risk following the Canterbury earthquakes in New Zealand offered a unique opportunity to investigate the economic effect of disaster-mitigation regulations on the commercial building stock. A difference-in-differences (DD) framework was used to determine whether earthquake risk has been capitalized into the property prices of buildings constructed prior to 1976, as a response to the national policy requiring assessment and strengthening (or demolition) of the existing earthquake-prone building stock. A negative externality is found in the policy announcement on affected (pre-1970s) office and retail buildings which caused office buildings to suffer a 12.5% stigma discount. However, retail properties were less impacted suffering a 2.3% stigma loss. The value of the commercial building stock has been affected by the policy. These findings provide policy-makers with timely evidence as to the economic effects of New Zealand’s earthquake-prone buildings policy. Facing losses in property value and financial responsibility for retrofitting their assets, building owners will be looking for a workable set of regulatory and non-regulatory incentives to encourage disaster risk management and protect the built environment. 相似文献
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Natural disasters greatly impact the environment of affected societies with often unknown consequences. In this study we examine the impact that the Canterbury Earthquakes of 2010–2011 had on the distribution of alcohol outlets in Christchurch, New Zealand. Specifically, we compare the distribution of both on-site and off-site alcohol outlets pre- (December 2009) and post-earthquake (December 2014) and use spatial regression models to identify whether any neighbourhood-level factors predict the observed redistributions. Overall, the number of alcohol outlets decreased by almost 13% after the Canterbury Earthquakes. However, we found a moderate increase in the clustering of both outlet types of outlets in the post-quake period. Increases in rates of both on-site and off-site alcohol outlets in neighbourhoods were positively associated with the percentage of residents who resided in their neighbourhood < 5 years and with neighbourhood crime rate change, while negative associations were found with percentage population aged between 15 and 29 years. The results suggest that the changing spatial distribution of alcohol outlets in Christchurch was not random but driven, in part, by the emergent demographic composition of neighbourhoods. The significant practical and policy implications of a redistribution of alcohol outlets are outlined providing a tangible link between empirical research and practice in an urban environment plagued with post-disaster spatial and social uncertainties. 相似文献
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目前,阻尼器在工程结构减隔震控制领域的应用已极为广泛,但存在中小地震作用下阻尼器的位移和速度等较小时,阻尼器难以充分发挥耗能能力的问题。因此近年来阻尼器响应放大技术得到了国内外学者的广泛重视,并利用连杆机构、齿轮机构、杠杆机构、跨层支撑等提出了多种阻尼器响应放大装置。全面综述国内外阻尼器响应放大技术的研究和应用进展,包括装置构造和作用机理等。同时,分析现有阻尼器响应放大技术在遭遇极罕遇地震作用时阻尼器更容易失效等方面的不足,指出响应放大技术的研究和发展方向,以期为阻尼器响应放大技术的发展和极罕遇地震作用下确保工程结构的安全提供有效思路。 相似文献
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Experimental and analytical investigation of the seismic out‐of‐plane behavior of unreinforced masonry walls In addition to the vertical and horizontal load‐bearing in‐plane, masonry must also withstand out‐of‐plane loads that occur in earthquake scenarios. The out‐of‐plane behavior of unreinforced masonry walls depends on a variety of parameters and is very complex due to the strong non‐linearity. Current design methods in German codes and various international codes have not been explicitly developed for out‐of‐plane behavior and contain considerable conservatism. In the present work, shaking‐table experiments with heat‐insulating masonry walls have been conducted to investigate the out‐of‐plane behavior of vertical spanning unreinforced masonry walls. As shown in previous numerical investigations, important parameters are neglected in existing design and analysis models and the out‐of‐plane capacity is underestimated significantly. In the conducted experiments the results of these numerical investigations are verified. Furthermore, the development of an analytical design model to determine the force‐displacement relationship and the out‐of‐plane load‐bearing capacity considering all significant parameters is presented. 相似文献
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在山区地形、砾岩分布条件下 ,采用三维高分辨率地震勘探技术 ,查明了杨村煤矿 13采区构造分布情况 ,为优化矿井采区设计 ,合理布置工作面 ,提高煤炭回收率 ,保障安全生产 ,提供了技术依据。 相似文献
8.
结合一住宅小区的结构设计.对异型柱框架、框一剪结构的破坏机理、计算理论和结构构造进行了探讨,供设计同仁参考。 相似文献
9.
以下行分层开采的我国东北某大型煤矿为工程背景,通过现场微震观测和工程数据分析,探索矿震能量释放的时空分布规律及其工程应用价值.发现在没有显著的外部长周期调制动力流入的矿区,各相同地应力强度环境持续开采引发的矿震能量累积释放的时域分布均符合3参数的S形Logistic阻滞增长模型;不同地应力强度环境间,该模型的3个参数是地应力强度的自相似函数.通过最大主应力建立起不同地应力强度环境开采进程的典型矿震能量释放谱,定量揭示了开采活动与矿震能量释放间的内在联系及力学机理. 相似文献
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