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1.
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.  相似文献   
2.
为研究不同岩层倾角陡倾顺层软硬互层斜坡在地震作用下的动力响应及失稳机理,以汶川地震中干磨坊滑坡和水磨沟滑坡为原型,结合三维离散元技术开展两种软硬互层斜坡对比分析。动力响应分析结果表明:在相同地震荷载作用下,陡倾软硬互层60°斜坡模型的PGA(峰值地面加速度)放大系数随着高程的增加表现出非线性增长,在坡顶动力响应最为强烈;陡倾软硬互层80°斜坡模型PGA放大系数随着高程的增加表现出先增大后减小再增大的节律性变化,在坡高1/3处和坡肩部位动力响应最为强烈。失稳机理分析结果显示,在地震荷载作用下:陡倾软硬互层60°斜坡模型发生滑移-弯曲式溃滑,斜坡的破坏流程机制分为四个阶段,即①裂缝扩展-层间错动阶段、②坡脚岩体弯曲隆起阶段、③上部岩体横向滑移阶段、④弯曲剪断-整体失稳阶段;陡倾软硬互层80°斜坡模型发生滑移-下部弯曲-上部倾倒式破坏,斜坡的破坏流程机制分为四个阶段,即①微裂隙扩展阶段、②层间错动-局部裂隙贯通阶段、③下部岩体弯曲阶段、④上部岩体倾倒破坏阶段。  相似文献   
3.
《Soils and Foundations》2021,61(6):1681-1698
The hinge type of precast concrete arch culvert was introduced to Japan from France in the 1990s in consideration of the saving of labor, shortening of the construction period, and high quality control of the concrete members. However, due to the 2011 off the Pacific Coast of Tohoku Earthquake (March 11, 2011), the three-hinged precast arch culverts that had been constructed in Japan at the beginning of the period when precast arch culverts were firstly introduced, suffered damage, which spoiled their serviceability. According to the extent of the damage and the type of culverts that were damaged, the longitudinal structural connectivity of the culverts was assumed to be one of the possible reasons for the reported damage mechanism. Therefore, the objective of this paper was to clarify how strongly the longitudinal structural connectivity influenced the longitudinal seismic behavior of the three-hinged arch culverts. To achieve this objective, an elasto-plastic finite element analysis was conducted with an analytical model that could capture the characteristics of the damaged culverts. Simultaneously, a penalty method with the bi-linear spring model was applied as a solution to the contact-impact problems of the precast segmental arch members. As a result, it was found that the weaker longitudinal structural connectivity in the damaged culverts allowed the torsional displacements of the arch members to induce critical damage to the arch members, namely, edge defects in the arch crown and concrete foundation. The numerical results proved the unignorable influence of the longitudinal structural connection on the possible damage to three-hinged arch culverts.  相似文献   
4.
尾矿坝的稳定是矿山安全生产的重要保障。为了研究在高烈地震带内某上游式膏体排尾尾矿库的稳定性,用Slide软件计算正常及地震工况下湿排和膏体排尾尾矿库的稳定性并进行稳定性分析。结果表明,湿排尾矿库的坝体抗滑稳定最小安全系数随地震烈度的增加降低较快,膏体排尾尾矿库的坝体抗滑稳定最小安全系数随地震烈度的增加降低较慢;湿排和膏体排尾坝体抗滑稳定最小安全系数降低规律基本一致,降低曲线呈"S"型,降低过程可分为降低初始时期、加速时期以及减速时期;不同地震烈度下膏体排尾与湿排坝体抗滑稳定最小安全系数的比值K先增加后降低;湿排尾矿库的稳定性受地震影响较大,膏体排尾尾矿库的稳定性受地震影响较小。因此,在高烈地震带内,采用膏体排尾的尾矿库更稳定。  相似文献   
5.
《Soils and Foundations》2022,62(2):101106
This study investigates three aspects of the dynamic response of earth-core rockfill dams (ECRDs) under earthquake loadings, including induced shear strain, increased fundamental period, and shear modulus reduction. A database of the recorded ground motions of ECRD cases in Japan is analyzed to carry out this study. The required response parameters as mentioned above are extracted by analyzing the acceleration time histories recorded at the dams’ crests and foundations. Subsequently, statistical analyses are performed to achieve the objectives of this study. A graph is developed describing the change in the dam’s fundamental period with the induced shear strain, and it is observed that the increase of the dam’s period is dependent on the increase in the shear strain levels. A relationship is established to estimate the anticipated levels of shear strain from the intensity measure (IM) of the earthquake signals. In the proposed predictive relationship, a new IM is used that can adequately characterize the severity of an earthquake. Finally, a curve and a range are suggested for the average shear modulus degradation of the ECRD’s core materials. The presented empirical graphs and relationships in this study are valuable tools to obtain an appropriate perception of dams’ nonlinear behaviour under strong earthquake excitations.  相似文献   
6.
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.  相似文献   
7.
山地小城镇避震疏散通道震后连通 性直接关系到受灾群众能否安全转移、救灾 工作能否顺利展开。本文以地震高发的滇西 山地小城镇耿马傣族佤族自治县县城(下称 耿马县城)为研究对象,以沿街建筑易损性 灰色度评价测算各路段的连通概率值,分析 在不同地震烈度下避震疏散通道的连通性。 研究表明:耿马县城发生地震烈度为7度及 以下地震灾害时,整体避震疏散通道网络连 通度较好,随着地震烈度的增大,避震疏散 通道网络连通度下降,甚至有部分避震疏散 通道不能连通。因此,在地震灾害发生前, 应进行避震疏散通道的连通性的评估,并根 据评价结果有效布置救灾物资,加固改造连 通性差的避震疏散通道。  相似文献   
8.
A scaled plane-strain shaking table test was conducted in this study to investigate the seismic performance of a Geosynthetic Reinforced Soil-Integrated Bridge System (GRS-IBS) with a full-length bridge beam resting on two GRS abutments at opposite ends subjected to earthquake motions in the longitudinal direction. This study examined the effects of different combinations of reinforcement stiffness J and spacing Sv on the seismic performance of the GRS-IBS. Test results show that reducing the reinforcement spacing was more beneficial to minimize the seismic effect on the GRS abutment as compared to increasing the reinforcement stiffness. The seismic inertial forces acted on the top of two side GRS abutments interacted with each other through the bridge beam, which led to close peak acceleration amplitudes at the locations near the bridge beam. Overall, the GRS-IBS did not experience obvious structure failure and significant displacements during and after shaking. Shaking in the longitudinal direction of the bridge beam increased the vertical stress in the reinforced soil zone. The maximum tensile forces in the upper and lower geogrid layers due to shaking happened under the center of the beam seat and at the abutment facing respectively.  相似文献   
9.
It has been studied to analyze the operations in nuclear power plants (NPPs) where the human error could make a trigger to the nuclear disaster following the earthquake in South Korea. The earthquake warning system and its related control algorithm are modeled by the machine learning (ML) of artificial intelligence (AI) where the neural networking is done as a major role. The AI-based control system could give the very good performance in the earthquake incident which is shown by the system dynamics (SD) based simulations. Hence, the nuclear safety system needs the AI based alarming technology which could be a much more advanced control system incorporated with the conventional multiple-barrier concept in NPPs.  相似文献   
10.
付飞  刘刚 《室内设计》2016,(2):65-70
传统城镇街道网络受地形、历史 发展格局等因素影响,呈现出小尺度、疏密 结构复杂等特征。本文选取“汶川地震”受 灾严重的羌峰村,模拟震后街道通行的“资 源”分布,进行交通网络需求与网络空间表 征、网络节点连接距离的关联性研究,并构 建街道网络的优化格局。研究结果表明:引 力场安全格局模型参数中,节点介中心值可 较好反映人们对最短路径的选择倾向和街 道网络流量的变化趋势,而街道空间句法的 中心性、最短路径中心性、激发引力场的安 全格局中心点介中心性均有高度一致性和可 辨性;通过引力场优化模型提出的避让策略 缓解了节点的拥堵程度,使整个街道网络呈 现出动态平衡的状态,形成了高效街道网络 的引力场安全格局。  相似文献   
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