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71.
The geography information system of the 1303 Hongton M=8 earthquake has been established. Using the spatial analysis function of GIS, the spatial distribution characteristics of damage and isoseismal of the earthquake are studies. By comparing with the standard earthquake intensity attenuation relationship, the abnormal damage distribution of the earthquake is found, so the relationship of the abnormal distribution with tectonics, site condition and basin are analyzed. In this paper, the influence on the ground motion generated by earthquake source and the underground structures near source also are studied. The influence on seismic zonation, anti-earthquake design, earthquake prediction and earthquake emergency responding produced by the abnormal density distribution are discussed. Foundation item: National important fundamental research “The Basic Research of Important Project in Damage Environment” and The important project “The Seismic Hazard Assessment Research and Anti-earthquake Structure Research” from China Earthquake Administration during the 10th Five-year Plan. Contribution No. 04FE1008, Institute of Geophysics, China Earthquake Administration.  相似文献   
72.
化学腐蚀下砂岩三轴细观损伤机理及损伤变量分析   总被引:10,自引:4,他引:10  
陈四利  冯夏庭  周辉 《岩土力学》2004,25(9):1363-1367
利用CT识别技术对化学腐蚀下的砂岩进行了三轴加载全过程的即时扫描试验,得到了在不同级荷载作用下砂岩的压密、微裂纹萌生、扩展和破裂的CT图像和CT数,分析了砂岩损伤演化的细观机理。同时,建立了一个基于化学腐蚀影响和CT数的损伤变量模型。  相似文献   
73.
Bakir  P.G. 《Natural Hazards》2004,33(3):405-425
While laboratory and analytical studies can provide valuable information about earthquake hazard mitigation, the most effective educator is the impact of a full-scale earthquake on a full-scale city. The recent earthquakes in Turkey showed that the governmental as well as individual attitudes towards earthquakes did not represent proportionate responses to the risk levels concerned. Turkey had weaknesses in preparing, planning, mitigating and responding to disasters in spite of the known seismic vulnerability of the country. Many steps have been taken after 1999 earthquakes in Turkey, however, the preparations largely concentrate on the response and recovery phases and a fundamental step to reform the current disaster management system and steps to rehabilitate the vulnerable building stock has not been undertaken until today. This would involve changing the present laws and regulations and de-centralising the disaster management system. The aim of this paper is to propose a national mitigation strategy for Turkey for a time-frame of 10 years. The model proposed is a very comprehensive model for earthquake risk reduction in Turkey and within this context, the legislative and technical aspects of mitigation will be discussed in detail. Strategies for mitigating and retrofitting the existing building stock will also be proposed.  相似文献   
74.
Zhang  Jiquan  Okada  Norio  Tatano  Hirokazu  Hayakawa  Seiji 《Natural Hazards》2004,31(1):209-232
Agro-meteorological hazards such as drought, waterlogging and cool summer occur with very high frequency and affect maize production and social-economic development in the maize-growing region of Songliao Plain, China. Moreover, both the frequency of these hazards and loss from them are considered to be increasing with global warming. The purpose of this paper is to quantitatively analyze the relationships between the fluctuation of maize yield and drought, waterlogging and cool summer, and to evaluate the consequences of these hazards in the maize-growing area of Songliao Plain, taking Lishu county as a case study area based on GIS (Geographic Information System). Crop yield-climate analysis and regression analysis were employed to analyze and quantify relationships between the fluctuation of maize yield and drought, waterlogging and cool summer, and to evaluate the consequences of these hazards. The parameters and model of damage evaluation were presented using weighted comprehensive analysis, and the degree of damage of drought, waterlogging and cool summer to maize production was comprehensively evaluated and regionalized. It is shown that from 1949 to 1990, the negative value years of the fluctuation of maize yield due to meteorological hazards accounted for 55% of seasons, of which 14% was caused by drought, 30% by waterlogging, 4% by cool summer and drought, 9% by cool summer and waterlogging, 13% by drought and waterlogging, 30% by drought, waterlogging and cool summer. Studies on the instability and spatial variation of the fluctuations in maize yield in Lishu county showed that the middle plains are stable areas to climatic influence, while southeastern hills and low mountains, the low lands of the plains along the East Liao River and the western plain are unstable areas in terms of areas in maize yield. The synthetic index of the degree of damage to maize of drought, waterlogging and cool summer showed a strong positive correlation with the ratio of the amount damaged to the normal yield of maize. This suggests that this index can be used to evaluate such damage. The degree of damage of drought, waterlogging and cool summer to maize in Lishu county shows the regional characteristics, which increase gradually from the center to the west and east, this being almost identical with the spatial distribution of the fluctuation of maize yield due to these hazards. This study can be expected to provide the basis for developing strategies to mitigate agro-meteorological hazards and reducing the losses from them, and adjust the medium and long-term distribution of agricultural activities so as to adapt to environmental changes.  相似文献   
75.
This paper presents the results of a comprehensive monitoring program designed to investigate the extent of blast induced damage experienced by rock masses extracted by bench stoping methods. An array of triaxial geophones and extensometers were used to monitor blast vibration attenuation and measure hangingwall deformations during stope extraction. In addition, pre and post surveys of the hangingwall rock mass were conducted using a TV borehole camera and cavity survey instrumentation. These surveys were later used to calibrate damage profiles into the stope hangingwalls.

Peak particle velocity, hangingwall deformation measurements and stope surveys were used to develop a site specific damage model that allowed engineers to asses drilling and blasting configurations to minimise the extent of pre-conditioning and damage. In addition the study included the analysis of the frequency response, displacements and accelerations experienced by the excavation as extraction and mine filling progressed. This work aimed at improving our understanding of the influence of blasting on the dynamic behaviour of stope hangingwalls.

The study demonstrated that estimates of the maximum extent of rock mass pre-conditioning and/or damage made through the application of the Holmberg-Persson approach compared well with measured results. In addition, the study found that dynamic loading imparted on an exposed hangingwall from subsequent stope blasting was also expected to contribute to rock mass weakening and that mine filling was crucial to arrest further deterioration. Hangingwall accelerations were used to demonstrate that larger openings may be more susceptible to dynamic loading.  相似文献   
76.
介绍了2003年12月1日新疆昭苏6.1级地震的现场考察结果.该地震宏观震中位于受灾最重的兵团农四师76团11连西侧,极震区烈度为Ⅷ度;圈定出Ⅷ度、Ⅶ度和Ⅵ度3条等震线.此次考察还着重考察了震区各类典型建筑的受损特征,对受损原因作了初步分析,所取得的经验可供类似地区抗震设防和民房改造工作参考.  相似文献   
77.
Estimating severity of liquefaction-induced damage near foundation   总被引:1,自引:2,他引:1  
An empirical procedure for estimating the severity of liquefaction-induced ground damage at or near foundations of existing buildings is established. The procedure is based on an examination of 30 case histories from recent earthquakes. The data for these case histories consist of observations of the damage that resulted from liquefaction, and the subsurface soil conditions as revealed by cone penetration tests. These field observations are used to classify these cases into one of three damaging effect categories, ‘no damage’, ‘minor to moderate damage’, and ‘major damage’. The potential for liquefaction-induced ground failure at each site is calculated and expressed as the probability of ground failure. The relationship between the probability of ground failure and the damage class is established, which allows for the evaluation of the severity of liquefaction-induced ground damage at or near foundations. The procedure presented herein represents a significant attempt to address the issue of liquefaction effect. Caution must be exercised, however, when using the proposed model and procedure for estimating liquefaction damage severity, because they are developed based on limited number of case histories.  相似文献   
78.
Data archives of seismic fault-induced damage   总被引:1,自引:0,他引:1  
The study of earthquake engineering requires an understanding of various processes by which structures are seriously damaged. For this, archiving available data in a systematic way will be quite necessary. Taskforces of both Japan Society of Civil Engineers (JSCE) and Japan Geotechnical Society (JGS), with a mission of establishing remedial measures for fault-inflicted damage to civil infrastructures, have been investigating previous examples of fault-related damages. Some of their important activities were further expanded as a subject of EqTAP project (Development of Earthquake and Tsunami Disaster Mitigation Technologies and Their Integration for the Asia-Pacific Region). This paper introduces some examples from the JSCE/JGS/EqTAP Data Archives, which can give some hints for rational remedial or design measures for civil-infrastructures whose constructions across faults were/are unavoidable.  相似文献   
79.
Introduction The ground motion is generally estimated by attenuation relation in seismic hazard assesment.The attenuation relation is usually the function of earthquake magnitude and distance.Actually the focal mechanism and other source parameters may also have significant impacts on the ground motion,especially in the near-source region.Recent post-earthquake investigations show that the damages have close relation with the closest fault-plane distance.On August16,2003,a MS=5.9earthquake o…  相似文献   
80.
从信息技术的角度看,工程勘察实际上是一种“信息获取、信息理解和信息应用”的过程。作为一项技术和服务,工程勘察的信息化应由工程勘察业务信息化和工程勘察管理信息化两方面组成。工程勘察信息化的作用包括信息化辅助业务和管理、信息化支撑业务和管理以及信息化提升业务和管理三个层次。当前,有必要对工程勘察企业信息化的模式、工程勘察业务信息化提升的方式和工程勘察信息化的标准化等问题做进一步研究,以推动工程勘察信息化向深度和广度发展。  相似文献   
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