5．12汶川大地震中给排水管道的震害及其分析

本文介绍了给排水管道在汶川大地震中的震损情况,在分析总结管道地震破坏特点的基础上,对给排水管道抗震设计提出了建议,供工程设计人员参考。     

5．12四川汶川大地震中给排水结构的震害及其分析

本文介绍了给排水工程结构在2008年5月12日四川省汶川大地震中的震害情况,并分析总结了地震破坏的特点,从而对给排水工程结构抗震设计提出了建议,供工程设计人员参考。     

汶川震后重建之观念与技术探讨——以台湾集集9.21震灾为鉴

大地震造成生命财产重大损失之原因,虽说源自天灾,但造成生命财产之惨痛伤害者,则以人谋不臧所致之人祸居多!从台湾集集9.21震灾调查报告与本次四川汶川大地震之灾损状况之雷同,均可证实。造成汶川与集集之重大震灾原因,认为主要者应系全民防震观念尚未建立及建筑物之防灾抗震技术未曾落实与不完备二大人祸因素所造成。从全民防震抗震角度出发,先从观念层面上扼要探讨地震及震灾发生之基本原因,再从技术层面上探讨建筑物之防灾抗震技术,最后汇整所参与之《9.21集集大地震建筑物震害调查初步报告》,以提供汶川5.12大地震灾后检讨与重建之参考。     

鄂尔多斯地块重力均衡的地球动力学意义

本文利用鄂尔多斯地块及其周边地区高精度的数字地形和实测重力资料,采用A iry重力均衡模式,计算出了鄂尔多斯及周边地区（32°-43°N,102°-117°E）的重力均衡异常值。通过对该地区重力均衡异常的分析,结合该地区的地震活动性等研究成果,表明大部分地震都沿着均衡状态发生明显变化的地区附近发生。     

Annual limit-state frequencies for partially-inspected earthquake-damaged buildings

A procedure is presented for estimating an “annual limit-state frequency”, that is, the mean annual frequency of exceeding a (e.g. seismic-drift) limit state, for a partially-inspected earthquake-damaged SMRF building with fractured beam-column connections. Typically, inspection of all the moment-resisting connections in a building for fractures is prohibitively expensive. Motivated by this reality, the proposed procedure (developed as part of the SAC Steel Project) accounts for the uncertainty, due to incomplete inspection, in the total number and locations of fractured connections. Since the procedure can also take into account the aftershock ground motion hazard, an annual limit-state frequency estimated for a damaged building can serve as a basis for deciding, for example, whether to permit occupancy soon after the main-shock. Conversely, the estimated annual limit-state frequency can be used to guide inspection decisions, such as whether to inspect more connections and thereby reduce the uncertainty in the state of damage.     

Life-cycle optimization in the establishment of performance-acceptance parameters for seismic design

A life-cycle formulation is presented for the determination of optimum values of the mechanical properties of a structural system exposed to seismic risk. The resulting values are intended for providing support for the establishment of performance-acceptance criteria and parameters for seismic design. A method is developed for the determination of expected damage functions in terms of simplified reference models of the complex nonlinear systems that are typical of engineering practice. The uncertainties associated with the use of the simplified model to estimate peak dynamic responses of the system of interest are accounted for by means of first-order second-moment probabilistic criteria. An illustrative application of the criteria proposed is presented, together with a discussion about the translation of the results of the optimization studies into engineering criteria and methods expressed in conventional design formats.     

An immersive virtual reality serious game to enhance earthquake behavioral responses and post-earthquake evacuation preparedness in buildings

Enhancing the earthquake behavioral responses and post-earthquake evacuation preparedness of building occupants is beneficial to increasing their chances of survival and reducing casualties after the mainshock of an earthquake. Traditionally, training approaches such as seminars, posters, videos or drills are applied to enhance preparedness. However, they are not highly engaging and have limited sensory capabilities to mimic life-threatening scenarios for the purpose of training potential participants. Immersive Virtual Reality (IVR) and Serious Games (SG) as innovative digital technologies can be used to create training tools to overcome these limitations. In this study, we propose an IVR SG-based training system to improve earthquake behavioral responses and post-earthquake evacuation preparedness. Auckland City Hospital was chosen as a case study to test our IVR SG training system. A set of training objectives based on best evacuation practice has been identified and embedded into several training scenarios of the IVR SG. Hospital staff (healthcare and administrative professionals) and visitors were recruited as participants to be exposed to these training scenarios. Participants’ preparedness has been measured along two dimensions: 1) Knowledge about best evacuation practice; 2) Self-efficacy in dealing with earthquake emergencies. Assessment results showed that there was a significant knowledge and self-efficacy increase after the training. In addition, participants acknowledged that it was easy, helpful, and engaging to learn best evacuation practice knowledge through the IVR SG training system.     

Geosynthetic-sheet pile reinforced foundation for mitigation of earthquake and tsunami induced damage of breakwater

Earthquake and tsunami impose great threats on the stability of a breakwater. Foundation of the breakwater is weakened by these forces, and it may result in collapse of the breakwater. Lateral flow of seabed soils take place beneath the breakwater, and excess pore water pressure is generated in the foundation by an earthquake that precedes tsunami. These factors may lead to excessive settlement and horizontal displacement of the breakwater. Tsunami introduces additional instability to the deformed breakwater. Due to water level difference between seaside and harborside of the breakwater during a tsunami, seepage occurs through its foundation, and it may cause pipping of seabed soils. Tsunami induced scouring of mound is also a big problem for the stability of the breakwater foundation. Finally, these result in failure of the breakwater foundation. Due to failure of its foundation, the breakwater may collapse and cannot block the tsunami. It results in entering of the tsunami in coastal areas. In order to make a breakwater resilient against earthquake and tsunami induced damage, reinforcing countermeasures were developed for foundation of a breakwater. Geogrid, gabions and sheet piles were used for reinforcing a foundation model. The effectiveness of the model is evaluated through physical modeling for mitigating the earthquake and tsunami induced damage. Shaking table tests were performed to determine the effectiveness of the reinforced model under different earthquake loadings. Tsunami overflow test was conducted on the same deformed model in order to see the effects of tsunami on the model. Comparisons were made between the unreinforced and reinforced foundations, and it was observed during the tests that the reinforced foundation performed well in reducing the damage of the breakwater brought by the earthquake and tsunami. Overall, this study is useful for practice engineering, and the reinforced foundation model can be adopted for designing a breakwater foundation to reduce damage triggered by an earthquake and tsunami in the future.     

极化SAR建筑物震害信息识别研究方法综述

合成孔径雷达具有全天候、全天时的对地观测优势,全极化合成孔径雷达（PolSAR）能够同时获取4种极化信息,利用PolSAR在震后进行震害评估具有及时性和准确性的优势。首先概述了PolSAR的发展状况及其在建筑物震害信息提取中的应用;其次,基于不同数据类型（多时相数据、多源数据、单时相数据）,概述了近10 a来 PolSAR数据在建筑物震害提取中的应用及其对比分析;然后,从极化分解方法、极化特征以及纹理特征3个方面对PolSAR数据的建筑物震害提取方法进行了详细阐述;最后,提出未来研究工作的设想,以期结合地理信息数据POI补充PolSAR在震害评估精度方面的不足。     

强震触发大型滑坡抛石运动特征研究

大光包滑坡是2008汶川地震触发的最大滑坡。滑坡位于四川省绵阳市安县高川乡,与汶川地震发震断裂直线距离5 km,滑坡最大长度4.6 km、最大高差0.73 km、规模近12亿m~3,改变了近10 km~2地形地貌。大光包滑坡除了具有超强动力与远程运动特征外,还表现出大规模块石高速抛射现象。在对大光包滑坡边界特征、运动和堆积特征分析基础上,研究了大光包滑坡抛石运动特征。结果表明:大光包滑坡抛石发生在滑坡南侧滑体,堆积于门槛石沟;坡体结构、大光包滑坡主滑体与对岸山梁相撞后产生的"刹车效应",以及门槛石沟开阔地形为抛石产生提供了条件;理论计算得出抛石速度平均值为99 m/s。