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Performance-based three-level fortification goal and its application in anti-dislocation countermeasures:A case study of Shantou Submarine tunnel
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作者 Tianqiang Wang Ping Geng +2 位作者 Guoguo Liu Changjian Chen Wenqi Gu 《Underground Space》 SCIE EI CSCD 2023年第5期251-270,共20页
The dislocation momentum is the design basis for anti-dislocation to tunnel when a tunnel crosses an active fault.The influence of different dislocation levels on tunnel performances is not clear.Thus,based on seismic... The dislocation momentum is the design basis for anti-dislocation to tunnel when a tunnel crosses an active fault.The influence of different dislocation levels on tunnel performances is not clear.Thus,based on seismic activity parameters at the site of interest and probability of fault dislocation,probability fault displacement hazard analysis(PFDHA)methodology was introduced in this paper to ascertain the fault dislocation level under different exceeding probabilities(63%,10%,and 2%–3%).Then,based on the definition of different ground motion strength and fortification goals of the tunnel,a three-level fortification goal with different performance requirements of the tunnel was proposed.The first attempt to use the proposed indexes including the maximum dislocation of the tunnel and maximum relative deformation of the tunnel was tried to evaluate deformation and failure states with an experimental approach.Subsequently,the feasibility of the three-level fortification goal was further investigated according to the self-defined qualitative description and quantitative indexes in the segmental design and sectional expansion tunnels comprehensively.The results show that the fault dislocations relying on PFDHA at the site of the Shantou Submarine Tunnel are firstly ascertained as 0.04,1.8,and 2.4 m respectively.Taking the fault dislocation as model input values into account,the dislocation mechanism of the tunnel under the three levels was revealed.More importantly,judging from the dislocation performance requirements of the three-level fortification goal,the tunnel deformation and failure states are mitigated by adopting the countermeasures.The sectional expansion design can well meet the requirements without the restriction of a strong earthquake,while the effectiveness of the segmental tunnel can be proved under frequently occurred and fortification earthquake.The final research results are expected to provide a new fortification goal for anti-dislocation hazard evaluation on expansion design in high-intensity seismic regions and segmental design in slight and moderate-intensity seismic regions. 展开更多
关键词 Fault-crossing tunnel PFDHA methodology three-level fortification goal Failure modes Anti-dislocation countermeasures
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Scientific and technical aspects of yogurt fortification:A review 被引量:7
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作者 Hadi Hashemi Gahruie Mohammad Hadi Eskandari +1 位作者 Gholamreza Mesbahi Mohammad Amin Hanifpour 《Food Science and Human Wellness》 SCIE 2015年第1期1-8,共8页
Food fortification is one of the most important processes for improvement of the nutrients quality and quantity in food.It can be a very cost effective public health intervention.Due to the high consumption rate of da... Food fortification is one of the most important processes for improvement of the nutrients quality and quantity in food.It can be a very cost effective public health intervention.Due to the high consumption rate of dairy products such as yogurt,fortification of these products will effectively reduce or prevent diseases associated with nutritional deficiencies.The aim of this investigation is to study the technical aspects involved in production of different types of fortified yogurts and their role in disease prevention and correction of deficiencies.In this paper,firstly,fortification is defined and the main reasons behind carrying out this process are presented and then yogurt production process and a variety of minerals,vitamins,and functional ingredients which are used in the process are briefly discussed.©2015 Beijing Academy of Food Sciences.Production and hosting by Elsevier B.V.All rights reserved. 展开更多
关键词 Yogurt fortification MINERALS VITAMINS FIBER
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Planning and Implementing Food Fortification Programs to Combat Micronutrient Malnutrition: Iron 被引量:1
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作者 Maria N García-Casal 《Food and Nutrition Sciences》 2014年第10期880-888,共9页
Iron deficiency anemia is the most prevalent nutritional deficiency in the world and food fortification is a cost-effective approach to combat it. This paper reviews the food fortification process with micronutrients,... Iron deficiency anemia is the most prevalent nutritional deficiency in the world and food fortification is a cost-effective approach to combat it. This paper reviews the food fortification process with micronutrients, with special emphasis on iron and the most critical steps and common difficulties found when implementing a program. The first step is to measure the magnitude of the problem and the groups affected by iron deficiency and anemia, to determine if there is a need for fortification. Then the adequate iron compound and vehicle should be selected, to obtain a bioavailable form of iron in a frequently consumed food item without changing the taste, appearance or cooking characteristics of the final food item or complete meals containing it, to assure the acceptance by consumers. Before implementation, bioavailability studies are in order for the fortified food item and for complete meals especially typical or traditional meals, followed by field studies and pilot tests. Once implemented, the program should be monitored and evaluated continuously, and the impact on health assessed periodically to give the program the flexibility for continuation made changes or finalization when necessary. Other key elements for successful implementation of food fortification programs include the presence of a viable food industry;available channels for food marketing and distribution;a health care system to identify and monitor micronutrient malnutrition in the population;institutions for education, treatment and evaluation of the impact of the program;and continuous and effective input into the planning, implementation, monitoring and evaluation of the intervention to ensure sustainability of the intervention. 展开更多
关键词 Food fortification PROGRAMS ANEMIA IRON DEFICIENCY
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The Introduction of European Fortification in the Late Ming Period 被引量:1
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作者 Zheng Cheng Yu Yueyuan 《Chinese Annals of History of Science and Technology》 2017年第2期18-70,共53页
In the late Ming period,Xu Guangqi and other Catholic literati were actively involved with military affairs because of the invasion of the Manchu forces and the threat of uprisings.The story of how they imported Europ... In the late Ming period,Xu Guangqi and other Catholic literati were actively involved with military affairs because of the invasion of the Manchu forces and the threat of uprisings.The story of how they imported European cannons and gunners from Macao is now quite famous.However,the introduction of European fortifications,mainly the trace Italienne,in the same period is still relatively unknown.Xu Guangqi and his student Sun Yuanhua exerted considerable efforts in advocating European-style bastions.Xu not only received help from Jesuits,but also support from some Fujianese who were familiar with Intramuros,the Spanish walled city of Manila.In addition to Xu and Sun,Han Lin and Han Yun(also Xu’s students)prepared a Chinese treatise on European fortification architecture based on Italian sources and tried to put the knowledge into practice.Another relevant figure is Ma Weicheng,who allegedly directed the building of 32 angled bastions in three cities around 1640.Although a few recorded writings and practices of constructing European-style fortification appeared in the first half of the seventeenth century,soon afterwards the art of trace Italienne met its end prematurely in China.To a great extent,the swift collapse of the Ming dynasty eliminated the possibility of spreading the new defense technology.Throughout the eighteenth century,the Qing dynasty enjoyed long-term peace,and the warfare at the frontiers brought few threats to the city walls.There was thus little urgency to develop innovative defensive works and European fortification sunk into oblivion until the mid-nineteenth century. 展开更多
关键词 fortification FIREARMS technology transfer Jesuit Ming HISTORY MILITARY HISTORY
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Research on the seismic fortification level of offshore platform in Bohai Sea and adjacent areas
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作者 彭艳菊 吕悦军 +1 位作者 唐荣余 沙海军 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2005年第6期697-706,749,共11页
API code is introduced at first, and then a comparison of seismic character and seismic hazard between Bohai and Southern California is carried out. The analysis indicates both the seismic frequency and intensity and ... API code is introduced at first, and then a comparison of seismic character and seismic hazard between Bohai and Southern California is carried out. The analysis indicates both the seismic frequency and intensity and the seismic hazard of Bohai are much weaker than that of Southern California. API code states the strength level and deformation level of permanent structures in Southern California takes 200 a and several hundred to a few thousand years respectively. But in the reference codes in China, the seismic levels take 500 a and 10000 a for strength design and deformation design, and it seems too conservative. In China, the deformation level of class A structure takes 2%-3% probabilities of exceedance in reference period 100 a, and that of class B and C often takes 2%-3% in 50 a. Now that offshore platforms may cause server subsequent risk, it is safe to take 1% in 30 a as its deformation design level. On the basis of the above analyses and social economic level and the consistency with present codes, the strength design level and deformation design level of Chinese offshore platforms is suggested to take 200 a and 3000 a respectively. 展开更多
关键词 Bohai Sea offshore platform RP2A-WSD code seismic fortification level
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Protein Fortification of Corn <i>Tortillas</i>: Effects on Physicochemical Characteristics, Nutritional Value and Acceptance
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作者 Abril Lecuona-Villanueva David A. Betancur-Ancona +1 位作者 Luis A. Chel-Guerrero Arturo F. Castellanos-Ruelas 《Food and Nutrition Sciences》 2012年第12期1658-1663,共6页
The aim of this study was to evaluate the texture of corn dough as well as the nutritional quality and acceptance of corn cakes (tortillas) made either with a readymade commercial corn flour (CCF) or with a traditiona... The aim of this study was to evaluate the texture of corn dough as well as the nutritional quality and acceptance of corn cakes (tortillas) made either with a readymade commercial corn flour (CCF) or with a traditional way (nixtamal) both fortified with lys + tryp (L + T) or with a protein concentrate from Phaseolus lunatus added with L + T (PC + L + T). All treatments were analyzed to investigate the physical properties of the dough and tortillas as well as their physicochemical and nutritional quality. Results showed that cohesion was affected (p tortillas made with nixtamal showed no difference. Adhesion was not affected by treatments. Weight loss increased only in the fortified tortillas made with CCF (p tortillas increased with the fortification being the highest value 0.96 N. Color was not affected in tortillas made with CCF (p tortillas made with CCF and fortified with PC + L + T. Acceptance was greater for tortillas fortified with L+T alone. Protein fortification of tortillas made with either CCF or nixtamal is feasible using either L + T together or in combination with a PC from Phaseolus lunatus improving their nutritional value without negative effects on their physicochemical characteristics or acceptance. 展开更多
关键词 TORTILLA Amino Acids Child MALNUTRITION fortification
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Large, moderate, small earthquakes and seismic fortification criterion
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作者 SHEN Jian-wen(沈建文) +1 位作者 SHI Shu-zhong(石树中) 《Acta Seismologica Sinica(English Edition)》 CSCD 2004年第5期589-595,共7页
This paper discusses the relation between two-step seismic design and the standard of probability of exceedance, and the relation of three-levels seismic ground motion parameters given by probability method and compre... This paper discusses the relation between two-step seismic design and the standard of probability of exceedance, and the relation of three-levels seismic ground motion parameters given by probability method and comprehensive probability method. The relative size relations of the ground motions with 2%, 10%, 63% probability of exceedance in 50 years, namely large earthquake, moderate earthquake, and small earthquake, are discussed through a practical example of seismic hazard analysis. The methods to determine seismic fortification criterion are discussed. 展开更多
关键词 Seismic safety evaluation seismic fortification criterion earthquake resistance and disaster mitigation
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Optimization of Bioactive Fortification in Apple Snacks through Vacuum Impregnation Using Response Surface Methodology
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作者 H. P. Vasantha Rupasinghe Ajit P. K. Joshi 《Food and Nutrition Sciences》 2010年第2期45-52,共8页
Fortification of apple slices with t-resveratrol glucoside was obtained by vacuum impregnation (VI) of apple slices with a solution containing grape juice using response surface methodology (RSM). Three independent va... Fortification of apple slices with t-resveratrol glucoside was obtained by vacuum impregnation (VI) of apple slices with a solution containing grape juice using response surface methodology (RSM). Three independent variables of the VI process: vacuum pressure, application time and relaxation time, were coded at five levels in a central composite design. The VI-treated and dried apple slices were analyzed for t-resveratrol glucoside concentration and textural attributes (gradient and linear distance). Multiple response optimization revealed the following optimum VI condi-tions for the bioactive enrichment and improved textural quality of dried apple slices: vacuum pressure of 6 in. of Hg, application time of 10 min, and relaxation time of 22.5 min. 展开更多
关键词 APPLE SNACK Bioactive fortification Response Surface Methodology Texture Vacuum IMPREGNATION RESVERATROL
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A knowledge-to-action approach to food fortification: Guiding principles for the design of fortification programs as a means of effectively addressing micronutrient malnutrition
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作者 Laura A. Rowe David M. Dodson 《Health》 2012年第10期904-909,共6页
The gap that exists between research and the dissemination and implementation of research findings has been well established. Food fortification, one of the most cost-effective means of addressing micronutrient malnut... The gap that exists between research and the dissemination and implementation of research findings has been well established. Food fortification, one of the most cost-effective means of addressing micronutrient malnutrition, is no exception. With decades of implementation experience, there is need to strengthen mechanisms that effectively broadcast proven strategies to promote the successful implementation of fortification programs in changing, challenging, and dynamic environments. This requires clear channels of communication, well-defined in-country leadership, and a streamlined and focused approach that can be adapted to country-specific contexts. Based on experience designing and implementing fortification programs throughout Africa and a broad understanding of past successes and failures, a model is proposed that articulates often over-looked program elements critical to design and implementation. 展开更多
关键词 Food fortification MICRONUTRIENT MALNUTRITION PROGRAM DESIGN PROGRAM Implementation LEADERSHIP Africa
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Iodine and Selenium Intake in a Sample of Women of Childbearing Age in Palmerston North, New Zealand after Mandatory Fortification of Bread with Iodised Salt
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作者 Nurul Husna Shukri Jane Coad +2 位作者 Janet Weber Ying Jin Louise Brough 《Food and Nutrition Sciences》 2014年第4期382-389,共8页
Iodine deficiency is a worldwide public health problem, which has long been observed in many parts of the world, including New Zealand (NZ). The aim of this study was to assess iodine and selenium intake among women o... Iodine deficiency is a worldwide public health problem, which has long been observed in many parts of the world, including New Zealand (NZ). The aim of this study was to assess iodine and selenium intake among women of childbearing age in Palmerston North, New Zealand post mandatory fortification of bread with iodised salt. Fifty women of childbearing age completed a researcher-led questionnaire, including a semi-quantitative food frequency questionnaire. Iodine and selenium were analysed in 24-hour urine samples. The median urinary iodine concentration (UIC) was 65 μg/l with 30% below 50 μg/l;representing mild iodine deficiency according to the World Health Organization. The estimated median daily iodine intake (130 μg/day) was higher than the Estimated Average Requirement (100 μg/day) and higher than seen in women prior to fortification. The median excretion of selenium (32 μg/day) was slightly above level suggested as adequate (30 μg/day) and estimated median intake (57 μg/day) was higher than Estimated Average Requirement (50 μg/day). Selenium and iodine excretion were significantly correlated (Spearman’s rank order;r(50) = 0.547, p 0.001). The major contributors to iodine intake were milk (36%), bread (25%) and fish/seafood (15%). Participants had a mean intake of 2.5 slices of bread/day, which contributed approximately 14 to 20 μg of iodine. The majority of participants (74%) had iodised salt at home, but less than half (48%) used iodised salt exclusively. In conclusion, despite the mandatory fortification of bread with iodised salt in NZ, UIC of the study population indicates iodine deficiency although their estimated dietary intakes appear adequate. It is essential that government initiatives to improve iodine status are evaluated for their efficacy. 展开更多
关键词 IODINE SELENIUM IODINE Intake IODINE fortification Iodised Salt
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Storming Fortifications
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《Contemporary International Relations》 1999年第10期6-11,共6页
Feel for boulders while crossing the river. ---Deng Xiaoping After a 20-year track record of extraordinary successes, however, China’sleaders now confront the toughest issues since reforms began in 1978. The domes-ti... Feel for boulders while crossing the river. ---Deng Xiaoping After a 20-year track record of extraordinary successes, however, China’sleaders now confront the toughest issues since reforms began in 1978. The domes-tic economic growth rate is declining, and the surrounding region is confronting 展开更多
关键词 In Storming fortifications ASIA
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Lectotype optimization of mid-highrise residential building based on site conditions and seismic fortification intensity
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作者 秦力 程志辉 宋玉普 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2006年第6期718-722,共5页
A multi-objective lectotype optimization model based on site conditions and seismic fortification intensity is presented for mid-highrise residential buildings taking into account multiple items such as the original i... A multi-objective lectotype optimization model based on site conditions and seismic fortification intensity is presented for mid-highrise residential buildings taking into account multiple items such as the original investment, disaster losses and maintenance cost, the integral stiffness, the total ductility, the construction period, and so on. A Three-Scale Fuzzy Analytical Hierarchy process is proposed by introducing the Three-Scale Analytical Hierarchy process and the trapezoid fuzzy number. The result of a calculation example shows that the T-FAHP is practical. 展开更多
关键词 site conditions seismic fortification intensity mid-highrise residential building three-scale fuzzy analytical hierarchy process optimal selection
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The Planned Conservation of the Urban Fortifications of Tuscany: Satellite Interferometry as an Innovative Monitoring Technology for Asset Management
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作者 Daniela Ladiana 《Journal of Civil Engineering and Architecture》 2020年第5期263-270,共8页
The “Monitoring City Walls” research project by the University of Pisa approaches planned conservation as a process that pursues an in-depth understanding of historic city walls and their surroundings to define a sy... The “Monitoring City Walls” research project by the University of Pisa approaches planned conservation as a process that pursues an in-depth understanding of historic city walls and their surroundings to define a system of effective risk prevention. This multidisciplinary research adopts monitoring strategies and technologies at the large scale and in relationship to natural and urban conditions. The underlying logic frames the conservation of these historic fortifications within the more general mitigation of risks generated by context. The research aims to develop an innovative approach to monitoring ancient defensive structures in historical towns. The integrated use of advanced technologies allows for the control and, most importantly, advance identification of possible risks. These new technologies, in particular satellite interferometry, make it possible to improve and increase the operational capacity of monitoring processes by facilitating the acquisition and investigation of data relative to the system defined by ancient city walls and their surroundings. These technologies also represent a cost-effective tool for managing the important transition from the observation and study of individual monuments to the monitoring of large monumental complexes or even entire historical centers. 展开更多
关键词 Infrastructure monitoring fortificationS urban scale innovative technologies satellite interferometry
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Study on the Seismic Fortification Criteria of Offshore Platforms in the Bohai Sea
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作者 Lv Yuejun Peng Yanju +1 位作者 Wang Junqin Sha Haijun 《Earthquake Research in China》 2013年第1期109-120,共12页
This paper analyzes the seismicity and seismic risk distribution in the Bohai Sea. Based on the seismic design parameters of 46 platforms in the Bohai Sea, a statistic analysis is made on the ratios of the peak accele... This paper analyzes the seismicity and seismic risk distribution in the Bohai Sea. Based on the seismic design parameters of 46 platforms in the Bohai Sea, a statistic analysis is made on the ratios of the peak accelerations for different probability levels. In accordance with the two-stage design method, a scheme of two design seismic levels is proposed, and two fortification goals are established respectively for strength level earthquakes and ductility level earthquakes. Through analogy and comparison to the Chinese seismic code for buildings, it is proposed that the probability level for the strength and ductility level earthquakes takes return periods of 200a and 1000~2500a respectively, and we further expounded on its rationality. Finally, the fortification parameters in the sub-regions of Bohai Sea area are given in the light of seismic risk zonation and ground motion division. This article is a summary of experiences from many years of offshore platform seismic fortification work, and an exploratory study on the seismic fortification standards of offshore platforms in China, which may provide some references for the establishment of the standard. 展开更多
关键词 Bohai Sea Offshore platform Seismic fortification level
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Study on the Relationship of Seismic Design Ground Motion at Different Fortification Levels in the Xinjiang Region
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作者 Tang Lihua Gao Mengtan and Jiang Hui 《Earthquake Research in China》 2007年第4期372-378,共7页
The seismic risk analysis results of 79 cities in Xinjiang are presented, and the bedrock peak ground accelerations under three seismic levels and their ratios are discussed. Then, the relationship between earthquake ... The seismic risk analysis results of 79 cities in Xinjiang are presented, and the bedrock peak ground accelerations under three seismic levels and their ratios are discussed. Then, the relationship between earthquake environments and the seismic risk analysis results of different exceeding probabilities are researched. The results show that minor and major earthquake motion parameters calculated from moderate earthquakes do not have a consistent probability and the ratio of bedrock peak accelerations under different exceedance probabilities are dosdy correlated with earthquake environments. 展开更多
关键词 fortification level Design seismic ground motion XINJIANG
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A Comparison of Domestic and Foreign Seismic Fortification Standards for Electrical Equipment
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作者 You Hongbing Zhao Fengxin 《Earthquake Research in China》 2013年第4期553-566,共14页
It is of great significance to make comparative analyses of seismic fortification criteria at home and abroad for improving the anti-seismic capability of electrical equipment and revising the relevant national standa... It is of great significance to make comparative analyses of seismic fortification criteria at home and abroad for improving the anti-seismic capability of electrical equipment and revising the relevant national standards.A brief overview of American,Japanese,IEC standards and Chinese seismic design codes for electrical equipment is presented.Differences between these seismic fortification standards of electrical equipment are compared and analyzed in respect of the goal and level of seismic fortification and the seismic design spectrum.The advantages and disadvantages of Chinese standards are pointed out.Through learning from foreign experience on the determination of seismic fortification standards,recommendations are made for the improvement and revision of Chinese seismic fortification standards for electrical equipment. 展开更多
关键词 Electrical equipment Seismic fortification standard Comparative analysis Recommendations for improvement
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某线震后轨道设计方案研究 被引量:1
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作者 蔡向辉 张岷 +3 位作者 唐文国 刘启宾 褚卫松 张生延 《铁道标准设计》 北大核心 2024年第3期43-48,共6页
2022年1月8日门源发生6.9级地震,造成某线隧道二衬坍塌、桥梁梁体移位、接触网脱落等基础、设备严重损坏,并伴随钢轨折断、扣件脱落、道床倾斜等轨道震害,是我国高速铁路首次遭遇的强震作用下严重受灾事件。结合震后预测余滑变形量水平1... 2022年1月8日门源发生6.9级地震,造成某线隧道二衬坍塌、桥梁梁体移位、接触网脱落等基础、设备严重损坏,并伴随钢轨折断、扣件脱落、道床倾斜等轨道震害,是我国高速铁路首次遭遇的强震作用下严重受灾事件。结合震后预测余滑变形量水平150~300 mm,垂向100 mm条件下,在设防区段提出一种“三孔连体套管承轨台可调式WJ-8型扣件+长枕埋入式单层道床预留切割孔”新型大调整量无砟轨道结构方案。其中,三孔连体套管承轨台可调式WJ-8型扣件在既有WJ-8型扣件基础上通过增设铁承轨台、调距块和三联套管等部件可满足单股钢轨左右位置调整量达152 mm,长枕埋入式单层道床中预留切割孔,便于在基础变形超出扣件调整范围后切割纠偏;通过对余滑变形后线路拟合获得拨距包络图,确定了大调整量无砟轨道铺设范围。 展开更多
关键词 地震 余滑 破坏形态 活动断裂带 扣件 设防范围 轨道选型
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基于可拓理论的隧道洞口段动力响应规律研究
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作者 周佳媚 李瑞涵 +2 位作者 黄柯 崔凯琪 岳飞翔 《地下空间与工程学报》 CSCD 北大核心 2024年第2期625-635,共11页
隧道洞口段存在偏压浅埋、围岩破碎等情况,为探究隧道洞口段在地震作用下的动力响应规律并给出安全性定量评估指标,以雅万高铁6号隧道为依托建立数值模型,分别输入雅万人工合成波、EI波、KB波以及WL波4个地震波,基于可拓理论,建立可拓... 隧道洞口段存在偏压浅埋、围岩破碎等情况,为探究隧道洞口段在地震作用下的动力响应规律并给出安全性定量评估指标,以雅万高铁6号隧道为依托建立数值模型,分别输入雅万人工合成波、EI波、KB波以及WL波4个地震波,基于可拓理论,建立可拓物元模型,对采用数值模拟方法得出的隧道洞口段在最不利地震波作用下的弯矩、轴力、相对位移、加速度4个安全评估指标结果创建分区,以综合定量指标对雅万高铁6号隧道洞口段进行安全性评估,并提出了抗震设防长度。同时,分析了在不同地震波作用下的雅万高铁6号隧道洞口段的动力响应规律。结果表明:(1)在雅万人工波作用下,隧道各评估点动力响应程度约为其余3种天然波作用下动力响应程度的1.2倍;(2)各地震波计算所得4个评估指标沿纵向方向变化规律基本相同,轴力及弯矩峰值均出现在拱肩拱脚位置,相对位移峰值均发生在洞口处仰拱至拱顶测线,评估指标峰值发生时刻略微滞后于地震波峰值加速度对应时刻;(3)在雅万人工合成波作用下,雅万高铁六号隧道洞口段抗震设防长度为45~55 m,为隧道洞径的3.5~4倍。研究成果可为通过综合定量指标对隧道洞口段进行抗震安全性评估提供参考。 展开更多
关键词 高速铁路 隧道洞口段 数值模拟 抗震设防长度 可拓理论
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基于网格化和雷达图的建筑抗震设防最优烈度决策模型研究
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作者 昌毅 万凯 +4 位作者 刘新权 甘嘉豪 江元琪 胡文君 丁星妤 《世界地震工程》 北大核心 2024年第2期166-173,共8页
目前的建筑抗震设防最优烈度研究主要是从经济性或安全性进行考虑,然而合理的建筑抗震设防最优烈度需要综合考虑经济和安全性指标。本文将研究区域进行网格化,结合其周围历史地震数据进行地震危险性分析,以经济性指标和安全性指标作为... 目前的建筑抗震设防最优烈度研究主要是从经济性或安全性进行考虑,然而合理的建筑抗震设防最优烈度需要综合考虑经济和安全性指标。本文将研究区域进行网格化,结合其周围历史地震数据进行地震危险性分析,以经济性指标和安全性指标作为抗震设防最优烈度评价指标;运用博弈论组合赋权法确定各指标权重,建立基于网格化和雷达图的建筑抗震设防最优烈度决策模型,将该模型运用到四川省崇州市钢混结构和砖混结构的抗震设防研究中。通过对比分析该模型数据发现:钢混结构按8度设防时,相比于6度、7度和9度设防,其抗震设防综合效益分别提升57.2%、29.6%和3.9%;砖混结构按8度设防时,相比于未设防、6度、7度和9度设防的抗震设防综合效益分别提升60.6%、19.2%、2.4%和1.9%。因此,崇州市钢混结构和砖混结构按8度设防时,为最优抗震设防烈度,抗震设防综合效益最佳,验证了该模型的有效性。 展开更多
关键词 抗震设防 网格划分 博弈论 雷达图 决策模型
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乌兹别克斯坦9度区某超高层建筑结构设计与优化
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作者 闫锋 花炳灿 安东亚 《建筑结构》 北大核心 2024年第13期51-56,共6页
对于9度设防地区的超高层建筑,其结构设计基本由地震作用控制,因此抗震设计尤为重要。建筑消能减震技术可在提高结构地震安全储备的同时,降低整体工程造价,是结构优化设计的有效措施。对位于9度区的超高层建筑进行了结构方案选型对比、... 对于9度设防地区的超高层建筑,其结构设计基本由地震作用控制,因此抗震设计尤为重要。建筑消能减震技术可在提高结构地震安全储备的同时,降低整体工程造价,是结构优化设计的有效措施。对位于9度区的超高层建筑进行了结构方案选型对比、结构方案优化、减震设计方案比选、剪力墙内嵌钢板优化。结果显示,钢骨混凝土框架⁃核心筒方案相对于钢框架⁃支撑方案具备更高的成本优势;框架⁃核心筒方案可通过精细化设计作进一步优化;在此基础上,对钢骨混凝土框架⁃核心筒方案采用两种消能减震方案进行比选,结果表明,采用黏滞阻尼器方案的结构抗震性能明显优于采用黏滞阻尼墙方案;最后通过增大剪力墙竖向分布钢筋配筋率,对低区核心筒墙肢中的内嵌钢板进行了优化。 展开更多
关键词 9度抗震设防 超高层建筑 钢骨混凝土结构 框架⁃核心筒 消能减震
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