日本阪神淡路直下型地震震情初析

1995年1月17日发生的被日本气象厅命名为“1995年兵库县南部地震”,即国际新闻媒体曾称为(大)孤神(户)大地震,是日本自1923年关东大地震以来最为强烈的一次大地震,属罕见的都市直下型竖向地震,给日本阪神人民造成了巨大的生命和财产的损失。本文特收集了该次地震发生后,日本有关方面报道和有关震灾资料,进行了震情初步分析,并根据地震中发生的新情况提出了抗震防灾工作中应从中吸取的经验和教训,以及值得认真思考的问题,以供我国建筑结构与钢结构工作者作一参考。     

Damage to sewage systems caused by the Great East Japan Earthquake,and governmental policy

The Great East Japan Earthquake and its accompanying liquefaction and tsunami severely damaged many sewage systems including sewage pipes, manholes, pumping stations and sewage treatment plants over a wide area from Tohoku to the Kanto region. We conducted a questionnaire survey, interview survey and on-site confirmation in order to summarize and categorize the damage factors that shut down facilities such as drainage systems and treatment systems. We also studied the effectiveness of countermeasures to prevent liquefaction of the sewage system. The results showed that 90% of sewage pipes and 70% of manholes were damaged by liquefaction and that 54% of wastewater treatment plants and 75% of pumping stations were damaged by tsunami. Nevertheless, no severe damage was found along sewage pipe sections where liquefaction countermeasures had been executed, suggesting that the countermeasures are effective.     

Liquefaction in the Kanto region during the 2011 off the pacific coast of Tohoku earthquake

The present text is a summary of liquefaction events that occurred in the Kanto Region during the 2011 off the Pacific coast of Tohoku Earthquake, excluding those events in the Tokyo Bay area that are discussed elsewhere. Most liquefaction occurred in the abandoned river channels and former lakes that had been recently filled with liquefiable soils. Noteworthy was the damage to private housing lands and river dikes that had not been well treated against liquefaction risk. Many sites experienced repeated liquefaction after former earthquakes in 1923 or 1987, if they existed in those times. In contrast to the recent liquefaction-prone soils, more-aged sands scarcely liquefied because of what is called the “ageing” effect. The present study analyzed cases in Tokyo area to quantitatively assess the temporal development of ageing so that liquefaction risk in more aged soils might be reasonably assessed. In the appendix, remarks are made of the reliability of air-photo survey in quick detection of liquefaction sites.     

Scaling fire whirls

A fire whirl in an open space can cause devastating damage as was experienced in Hifukusho-ato, Tokyo, after the Great Kanto Earthquake in 1921. To understand the generation mechanism of the open-space fire whirls, 1/1000th scale-model experiments were conducted in a large, low-speed open-loop wind tunnel. In analyzing the experiments, there was found to be a critical lateral wind velocity that generated intense fire whirls. A scaling law that predicts the critical wind velocity was developed and validated by various data including scale-model experiments by other researchers and real urban fire whirls. A dimensional analysis is conducted to understand the effect of flow circulation on the increase in flame height. The simple analysis was supported by the results of numerical simulations by other researchers.     

高层住宅箱型转换层结构的模板施工技术

苏州市工业园区商旅新悦城项目,下部为3层框架结构的裙房,上部分别为12层和22层的框剪结构塔楼.塔楼在标高8m处设置了高为2 000 mm、上下翼缘板厚为180 mm的封闭式箱型结构转换层.针对这一特殊构造,采用了二次浇筑箱型转换层的模板支撑技术,满足了施工要求.     

Tokyo’s Dojunkai experiment: courtyard apartment blocks 1926–1932

Dojunkai apartments were constructed by the Japanese Government as a work of relief, after the Great Kanto Earthquake in Tokyo. These apartments were leading examples in concrete construction in Japan and were innovative in their exterior space design ideas and building organizational themes. Dojunkai apartments were designed not only as solutions to particular sites, but as possible models for the further development of well-planned, secure, and communal neighbourhood style residential developments. During 1920–1930, Japanese architects and designers were actively involved in experimenting with foreign concepts of urban remodelling and town planning. However while these town-planning concepts and theories were embraced by Japanese architects and town planners, the resultant apartment complexes suggest that they endeavoured to adapt and transform them to suit Japanese sensibilities and urban requirements. This paper examines the nature of these adaptations and transformations. The principles of exterior space design are deployed to examine and identify patterns in building arrangement and exterior space design for six selected Dojunkai apartments. This paper discusses the pre-existing models of urban planning in Japan to establish a relationship between the adopted foreign town-planning models and the pre-existing ideas of urban settlements in the Japanese society.     

武汉水岸星城超限高层建筑结构设计

武汉水岸星城住宅楼为53层主楼带1层地下室,主体高度162.45m,加局部小塔楼,结构总高178m,存在超高、楼板不连续、大底盘多塔等超限情况,文中介绍其结构构成、计算分析方法及采取的针对性抗震措施,可供类似工程设计参考。     

古塔观测数据的计算和变形分析

本文根据2013年全国大学生数学建模竞赛C题附录1的数据, 提出了确定古塔各层中心位置的八边形重心坐标拟合法,采用matlab计算出了各层的塔心坐标。利用顶层坐标相对于底层的倾斜量求得该塔的倾斜度;采用各层塔心坐标拟合曲线的曲率来描述弯曲度;并提出了利用同一个测试点与塔心连线发生的扭转角度来描述扭曲度的设想。     

Damage statistics (Summary of the 2011 off the Pacific Coast of Tohoku Earthquake damage)

The 2011 off the Pacific Coast of Tohoku Earthquake, which occurred on March 11, 2011, caused enormous damage, particularly to the strip of land along the Pacific Ocean from the Tohoku Region to the Kanto Region, due to seismic motion and the tsunami it triggered. This report presents an outline of the earthquake and summarizes the associated seismic damage to social infrastructure facilities.     

某高层建筑顶部异型网架的结构抗震分析和设计

本文结合工程实例,对位于高层建筑顶部装饰用异型网架的结构设计和地震反应进行了分析。在应用了常用的简化方法和抗震新规范推荐的楼面反应谱法进行了抗震设计后,应用振型分解反应谱法和楼面反应谱法进行了抗震验算,比较了两种方法的安全性和准确性,讨论了此类异型网架的自振特性、受力特点以及抗震性能,并给出一些设计上的建议和有益的结论。     

日本阪神·淡路震灾复兴规划的特征及启示

通过回顾日本"阪神·淡路大地震"灾后重建的规划建设过程, 阐述兵库县及神户市编制实施城市复兴规划的主要内容和构成框架, 分析复兴规划的实施过程以及相关政策措施.围绕"阪神·淡路震灾复兴规划", 从城市生活复兴、安全城市建构、城市街景再生、文化财保护等方面, 总结日本灾后复兴规划的特征和经验, 以期为我国汶川5·12大地震后的灾后重建规划提供借鉴.     

Characteristics of Tsunami Damage to the Tide Walls in Iwate Prefecture from the Great East Japan Earthquake

This research paper describes the tsunami damage to tide walls observed using aerial photographs and field investigations at 13 locations along the coast of Iwate Prefecture, where significant tsunami damage occurred as a result of the Great East Japan Earthquake. This paper also summarizes the characteristics of the damage. The tide walls in Iwate Prefecture were constructed on a ria （hilly type） coast, this geographical feature of lwate being different from that of the other disaster areas, primarily Miyagi and Fukushima Prefectures. The results of our investigations show that all the devastated tide walls suffered from overflow before being damaged. In particular, the sloping and vertical type tide walls with slope protection were damaged by scouring of the infill sand or back fill soil due to the overflow of the tsunami. In the case of vertical type tide walls without slope protection, damage was caused by scouring of the back fill soil.     

大清真寺高塔施工塔机的特殊附着技术

云南沙甸大清真寺宣礼塔的塔机附着方法,采用了塔机和建筑结构作为一体的特殊附着技术.高塔建设过程按照"合理增强建筑物结构与塔机附着相匹配的设计方案"进行施工,成功地完成了高塔塔身和塔机塔身自由摆动并相互作用条件下的稳定性施工作业.     

大底盘多塔楼结构基础隔震设计分析

本文针对某一大底盘多塔楼结构提出了基础隔震时的时程分析计算模型 ,编制了相应计算机程序 ,计算该结构在地震作用下各层的层间位移、加速度和剪力等地震反应 ,然后与该结构不隔震时的地震反应进行了比较。另外还对隔震层顶板在地震作用和温度作用下 ,是否能满足“平面内是刚性的”假设进行了空间分析。     

Damage patterns of river embankments due to the 2011 off the Pacific Coast of Tohoku Earthquake and a numerical modeling of the deformation of river embankments with a clayey subsoil layer

Due to the 2011 off the Pacific Coast of Tohoku Earthquake, which had a magnitude of 9.0, many soil-made infrastructures, such as river dikes, road embankments, railway foundations and coastal dikes, were damaged. The river dikes and their related structures were damaged at 2115 sites throughout the Tohoku and Kanto areas, including Iwate, Miyagi, Fukushima, Ibaraki and Saitama Prefectures, as well as the Tokyo Metropolitan District. In the first part of the present paper, the main patterns of the damaged river embankments are presented and reviewed based on the in situ research by the authors, MLIT (Ministry of Land, Infrastructure, Transport and Tourism) and JICE (Japan Institute of Construction Engineering). The main causes of the damage were (1) liquefaction of the foundation ground, (2) liquefaction of the soil in the river embankments due to the water-saturated region above the ground level, and (3) the long duration of the earthquake, the enormity of fault zone and the magnitude of the quake. In the second part of the paper, we analyze model river embankments on a foundation ground with various soil profiles, including a clayey soil layer and various ground water tables, using a dynamic liquefaction analysis method. From the analysis results, we find the effects of the soil profiles and the duration time of the earthquake motion on the deformation behavior of the river embankments. The results are consistent with those of the investigation of the features of the deformation and the failure of the embankments due to the 2011 off the Pacific Coast of Tohoku Earthquake.     

哈尔滨银河大酒店增层改造设计

哈尔滨银河大酒店为22层高层建筑,裙房部分为6层,塔楼部分有3层地下室,裙房部分有1层地下室,裙房右侧为4层框架结构俱乐部。塔楼部分为钢筋混凝土框架-剪力墙结构,裙房部分为钢筋混凝土框架结构。为将原高层与俱乐部所夹裙房由6层增层至22层,依据原房屋柱下基础的不同形式,对原柱下桩基础进行叠合加固,对原柱下独立基础用新增桩基础替换,并对原框架柱加固。由于裙房柱网布置与其新增楼层的柱网布置不同,在7层顶设置梁式转换结构。对本工程增层改造设计的若干关键问题的解决方法做了介绍,可供同类工程增层改造设计时参考。     

楼顶钢结构塔楼的抗震分析及设计建议

对高楼顶加钢塔这一结构形式的计算方法进行总结 ,并指出它们的实用范围。通过特例说明当高楼顶钢结构塔楼的基本频率与整体结构的固有频率相同或相近 ,且与地面扰频接近时 ,最易发生共振。经计算分析 ,总结出便于工程应用的简单计算公式 ,可供高楼顶钢塔计算和设计时参考。并结合工程实例 ,给出了高楼加高塔的设计计算建议     

Crustal stress changes and characteristics of damage to geo-engineering structures induced by the Great East Japan Earthquake of 2011

Bulletin of Engineering Geology and the Environment - T he Great 2011 Earthquake of East Japan, with a moment magnitude of 9.0, occurred off the shore of the Tohoku Region of Japan. Although...     

往复荷载作用下开洞砖塔子结构受力性能研究

结构开洞对砖石古塔的抗震能力影响显著,为研究不同开洞形式砌体古塔的抗震性能,以玄奘塔中部楼层为原型结构,设计制作了3种洞口开设方式的子结构模型,对其进行低周反复加载试验。观察了模型结构的破坏现象,得到了模型顶点水平荷载-位移滞回曲线与骨架曲线,对比分析了采用不同开洞方式时,模型结构的滞回特性、刚度退化以及耗能能力等。建立子结构有限元模型进行分析,将分析结果与试验结果进行对比。结果表明,在塔体结构平面尺寸相同的条件下,开洞口方式对结构的刚度、承载力及延性的影响显著;单面开洞、双面开洞及四面开洞时结构的破坏模式不同,但均为洞口顶部首先开裂,并与其他墙体内所产生的剪切裂缝将塔体分割为不同形状的破坏单元,改变了荷载原有的传递方式,从而影响结构的破坏模式;有限元分析与试验所得极限水平荷载相差均在15%以内,有限元模型能够较为准确地模拟开洞古塔子结构的受力性能。研究结果可为砖石古塔的抗震性能评估提供依据。     

Modeling the Evacuation of the World Trade Center Towers on September 11, 2001

Multiple evacuation models were used to simulate different WTC tower evacuations, subject to a number of assumptions. The goal of the modeling was to frame an understanding of actual evacuation findings on September 11, 2001. Simulations demonstrated that a phased evacuation (occupants of the emergency floor, the occupants on the floor above, and the occupants on the floor below were to evacuate to three floors below the emergency floor) would have taken between 4 min to complete (without delays in evacuation initiation) and 11 min to complete (with evacuation initiation delays between 0 min and 10 min). Total evacuation of a tower assuming a full occupant load would have required from 92 min to 142 min. NIST estimated that approximately 14,000 occupants would have been unable to evacuate from WTC 1 and WTC 2 on September 11, 2001 had the starting building population in each tower been 19,800, i.e., a full occupant load without visitors.