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Performance-based methodology for assessing seismic vulnerability and capacity of buildings

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Earthquake engineering and engineering Vibration 2010年第2期9卷 157-165页

作者： Lin Shibin1, Xie Lili1, 2,Gong Maosheng1,2 and Li Ming1,3.1.Institute of engineering Mechanics,China Earthquake Administration, Harbin 150080, China 2.school of civil engineering,Harbin Institute of Technology,Harbin 150090, China 3.school of civil engineering,Shenyang Jianzhu University,Shenyang 11016, China Institute of engineering Mechanics China Earthquake Administration Harbin 150080 China

This paper presents a performance-based methodology for the assessment of seismic vulnerability and capacity of buildings. The vulnerability assessment methodology is based on the HAZUS methodology and the improved capacity- demand-diagram method. The spectral displacement (Sd) of performance points on a capacity curve is used to estimate the damage level of a building. The relationship between Sd and peak ground acceleration (PGA) is established, and then a new vulnerability function is expressed in terms of PGA. Furthermore, the expected value of the seismic capacity index (SCev) is provided to estimate the seismic capacity of buildings based on the probability distribution of damage levels and the corresponding seismic capacity index. The results indicate that the proposed vulnerability methodology is able to assess seismic damage of a large number of building stock directly and quickly following an earthquake. The SCev provides an effective index to measure the seismic capacity of buildings and illustrate the relationship between the seismic capacity of buildings and seismic action. The estimated result is compared with damage surveys of the cities of Dujiangyan and Jiangyou in the M8.0 Wenchuan earthquake, revealing that the methodology is acceptable for seismic risk assessment and decision making. The primary reasons for discrepancies between the estimated results and the damage surveys are discussed.

关键词： performance-based vulnerability building damage seismic capacity software HAZUS

Key technology of mine underground mobile positioning based on LiDAR and coded sequence pattern

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中国有色金属学会会刊：英文版 2011年第S3期21卷 570-576页

作者： WANG Zhi1, 2, WU Li-xin1, 2, LI Hui-ying3.1. College of Resources and civil engineering, Northeastern University, Shenyang 110004, China 2. Academy of Disaster Reduction and Emergency Management, Ministry of civil Affairs and Ministry of Education, Beijing Normal University, Beijing 100875, China 3. College of Computer Science and Technology, Jilin University, Changchun 13.012, China [a] College of Resources and civil engineering Northeastern University Shenyang 110004 China [b] Academy of Disaster Reduction and Emergency Management Ministry of Civil Affairs and Ministry of Education Beijing Normal University Beijing 100875 China [c] College of Computer Science and Technology Jilin University Changchun 130012 China

Technologies of underground mobile positioning were proposed based on LiDAR data and coded sequence pattern landmarks for mine shafts and tunnels environment to meet the needs of fast and accurate positioning and navigation of equipments in the mine underground without satellite navigation signals. A coded sequence pattern was employed for automatic matching of 3. scans. The methods of SIFT feature, Otsu segmentation and fast hough transformation were described for the identification, positioning and interpretation of the coded sequence patterns, respectively. The POSIT model was presented for speeding up computation of the translation and rotation parameters of LiDAR point data, so as to achieve automatic 3. mapping of mine shafts and tunnels. The moving positioning experiment was applied to evaluating the accuracy of proposed pose estimation method from LiDAR scans and coded sequence pattern landmarks acquired in an indoor environment. The performance was evaluated using ground truth data of the indoor setting so as to measure derivations with six degrees of freedom.

关键词： LiDAR coded sequence pattern mobile positioning SLAM algorithm POSIT algorithm

Phase transition in the Zr_(60)Al_(15)Ni_(25) bulk metallic glass subjected to rolling at room temperature

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Science China(Technological Sciences) 2006年第6期49卷 655-662页

作者： YAN Zhijie1, 2, LI Jinfu1, ZHOU Yaohe1 & WU Yanqing3.1. State Key Laboratory of Metal Matrix Composites, school of Materials Science and engineering, Shanghai Jiao Tong University, Shanghai 20003., China 2. school of Materials Science and engineering, Taiyuan University of Science and Technology, Taiyuan 03.024, China 3. school of Environmental Science and engineering, Shanghai Jiao Tong University, Shanghai 20003., China State Key Laboratory of Metal Matrix Composites School of Materials Science engineering Shanghai Jiao Tong University Shanghai 200030 China school of Materials Science engineering Taiyuan University of Science Technology Taiyuan 030024 China school of Environmental Science engineering Shanghai Jiao Tong University Shanghai 200030 China

The microstructure evolution of the Zr60Al15Ni25 metallic glass during rolling at room temperature is investigated by X-ray diffraction (XRD), differential scanning calorimetry (DSC); high-resolution transmission electron microscopy (HREM). The results show that the values of full width at half maximum (FWHM) of the XRD patterns; exothermic enthalpy ΔH of DSC plots do not monotonically change with the variation of deformation degrees . As is not large than 20%, the values of FWHM; ΔH are lower than that of the as-cast state. When reaches 3.%, the values of FWHM; ΔH become larger than that of the as-cast state, while their values begin to decrease again as reaches about 85%. These results indicate that the reversible transitions between ordered; disordered atomic configurations occur during rolling, which is further verified by the HREM images. The reversible phase transition can be explained by the competition between the diffusion controlled reordering; shear-induced disordering during rolling.

关键词： metallic glasses, plastic deformation, phase transformations, shear bands.

The mathematical model of wetting angle of heterogeneous nucleation

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Science China(Technological Sciences) 2004年第4期47卷 391-397页

作者： HUANG Cheng1, SONG Bo1, MAO Jinghong2 & ZHAO Pei3.1. school of Metallurgical and Ecological engineering, University of Science and Technology Beijing, Beijing 100083. China 2. school of Material Science, University of Science and Technology Beijing, Beijing 100083. China 3. Central Iron and Steel Research Institute, Beijing 100081, China 1. school of Metallurgical and Ecological engineering University of Science and Technology Beijing 100083 Beijing China 2. school of Material Science University of Science and Technology Beijing 100083 Beijing China 3. Central Iron and Steel Research Institute 100081 Beijing China

The heterogeneous nucleation has been analyzed in terms of the thermodynamic theory, and the mathematical model of wetting angle of heterogeneous nucleation has been developed based on the dynamic requirements of hetero- and homogeneous nucleation. With the wetting angel model, the wetting angles of different catalysts in liquid iron have been calculated. The result shows that the wetting angle of most catalysts is smaller than 40, and the value of f() is far less than 1. The wetting angles of TiN, TiC and RE2O3.are smaller, while the wetting angle of MnO is bigger among the ordinary nucleation catalysts. The wetting angles calculated by this model are in agreement with the results of other research work.

关键词： heterogeneous nucleation, mathematical model, wetting angle, undercooling.

Conceptual design,data model and key techniques of“3. Assistant”

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中国有色金属学会会刊：英文版 2011年第S3期21卷 692-698页

作者： LI Qing-yuan1, ZHANG Xuan2, JIN Yang2, ZHOU Hui3. WANG Qian-jin3.WEI Zhan-yin1 1. Key Laboratory of Geo-Informatics, Chinese Academy of Surveying and Mapping, Beijing 10083., China 2. school of Geo-Science and Surveying engineering, China University of Mining and Technology, Beijing 100083. China 3. school of Geomatics, Liaoning Technical University, Fuxin 123.00, China [a] Key Laboratory of Geo-Informatics Chinese Academy of Surveying and Mapping Beijing 100830 China [b] school of Geo-Science and Surveying engineering China University of Mining and Technology Beijing 100083 China [c] school of Geomatics Liaoning Technical University Fuxin 123000 China

Conceptual design, data model and key techniques of "Geo-engineer 3. assistant", an underground 3. GIS oriented to geology and mine application, were discussed. In particular, the importance of high-order smoothing triangular pieces to surface's fine expression in geological modeling was emphasized. The contour mode is the most favorite mode of the three modes about surface expression: DEM, TIN and contour. Topology in underground 3. modeling with CAGD was compared. From the view of boundary and coboundary, which is soul of IS 19107 (Geographic information spatial schema), 3. underground topology was re-examined.

关键词： 3. assistant true 3. GIS fine expression of surface contour mode 3. topology

Quick image-processing method of UAV without control points data in earthquake disaster area

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中国有色金属学会会刊：英文版 2011年第S3期21卷 523-528页

作者： LI Chang-chun1, ZHANG Guang-sheng1, LEI Tian-jie2, 3. GONG A-du2, 3.1. school of Surveying & Land Information engineering, Henan Polytechnic University, Jiaozuo 454000, China 2. Key Laboratory of Environmental Change and Natural Disaster, Ministry of Education, Beijing Normal University, Beijing 100875, China 3. Ministry of civil Affairs/Ministry of Education of China Academy of Disaster Reduction and Emergency Management, Beijing Normal University, Beijing 100875, China [a] school of Surveying & Land Information engineering Henan Polytechnic University Jiaozuo 454000 China [b] Key Laboratory of Environmental Change and Natural Disaster Ministry of Education Beijing Normal University Beijing 100875 China [c] Ministry of civil Affairs/Ministry of Education of China Academy of Disaster Reduction and Emergency Management Beijing Normal University Beijing 100875 China

The methods of unmanned aerial vehicles images splicing rapidly and rectifying without control points data, only using auxiliary data recorded by unmanned aerial vehicle (UAV) system, were researched. Two algorithms were proposed, including UAV images auto- splicing rapidly after image blocking and UAV images rectifying based on pseudo center points of auxiliary data. When SIFT algorithm for UAV images splicing is applied, the accuracy is very high, but the efficiency is very low. The splicing efficiency is improved greatly based on SIFT algorithm after image blocking. The results show that rectifying accuracy is very high and has no visual dislocation when pseudo center points of auxiliary data is applied.

关键词： unmanned aerial vehicles SIFT algorithm blocking quickly splicing rectification

Impacts of permafrost changes on alpine ecosystem in Qinghai-Tibet Plateau

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Science China Earth Sciences 2006年第11期49卷 1156-1169页

作者： WANG Genxu1,3., LI Yuanshou2 , WU Qingbai2 & WANG Yibo3.1. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China 2. Cold and Arid Regions Environmental and engineering Research Institute, Chinese Academy of Sciences, Lanzhou 73.000, China 3. Resource and Environment school, Lanzhou University, Lanzhou 73.000, China 1. Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China 3. Resource and Environment school Lanzhou University Lanzhou 730000 China 2. Cold and Arid Regions Environmental and engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Alpine cold ecosystem with permafrost environment is quite sensitive to climatic changes and the changes in permafrost can significantly affect the alpine ecosystem. The vegetation coverage, grassland biomass and soil nutrient and texture are selected to indicate the regime of alpine cold ecosystems in the Qinghai-Tibet Plateau. The interactions between alpine ecosystem and permafrost were investigated with the depth of active layer, permafrost thickness and mean annual ground temperature (MAGTs). Based on the statistics model of GPTR for MAGTs and annual air temperatures, an analysis method was developed to analyze the impacts of permafrost changes on the alpine ecosystems. Under the climate change and human engineering activities, the permafrost change and its impacts on alpine ecosystems in the permafrost region between the Kunlun Mountains and the Tanggula Range of Qinghai-Tibet Plateau are studied in this paper. The results showed that the per- mafrost changes have a different influence on different alpine ecosystems. With the increase in the thickness of active layer, the vegetation cover and biomass of the alpine cold meadow exhibit a significant conic reduction, the soil organic matter content of the alpine cold meadow ecosystem shows an exponential decrease, and the surface soil materials become coarse and gravelly. The alpine cold steppe ecosystem, however, seems to have a relatively weak relation to the permafrost environment. Those relationships resulted in the fact that the distribution area of alpine cold meadow decreased by 7.98% and alpine cold swamp decreased by 28.11% under the permafrost environment degradation during recent 15 years. In the future 50 years the alpine cold meadow ecosystems in different geomorphologic units may have different responses to the changes of the permafrost under different climate warming conditions, among them the alpine cold meadow and swamp ecosystem located in the low mountain and plateau area will have a relatively

关键词： permafrost environment, alpine cold ecosystem, statistics relationship, climate change, impacts, Qinghai-Tibet Plateau.

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螺旋锚-岩石锚复合基础承载变形性能研究

建筑科学与工程学报 2024年

作者：马锦元李镜培刘祥国崔强赵勇高运兴 1.同济大学地下建筑与工程系 2.国网山东省电力公司泰安供电公司 3.中国电力科学研究院有限公司 4.国网山东省电力公司国网山东省电力公司中国电力科学研究院有限公司同济大学地下建筑与工程系国网山东省电力公司泰安供电公司

对山区输电线路工程中“上土下岩”的特殊地质条件，采用了一种新型螺旋锚-岩石锚复合基础形式。利用ABAQUS有限元软件建立了典型工况下的抗拔承载数值模型，并采用规范方法对单螺旋锚和单岩石锚的数值计算结果进行了验证，继而利用荷载... 详细信息

对山区输电线路工程中“上土下岩”的特殊地质条件，采用了一种新型螺旋锚-岩石锚复合基础形式。利用ABAQUS有限元软件建立了典型工况下的抗拔承载数值模型，并采用规范方法对单螺旋锚和单岩石锚的数值计算结果进行了验证，继而利用荷载-位移曲线探究了双锚复合基础抗拔承载力计算公式中的各项参数取值，在此基础上分析了双锚复合基础的抗拔承载机理和破坏模式。最后建立了不同工况下的数值模型，研究了锚盘数量、锚盘直径、岩石锚杆长度和锚固剂黏结强度对双锚复合基础抗拔承载力的影响。数值模拟结果表明，双锚复合基础相比单独岩石锚杆基础和单独螺旋锚基础的极限抗拔承载力有一定程度的提升；双锚复合基础的抗拔过程主要分为四个阶段：加荷初期由下部注浆体承担大部分荷载；基础塑性区持续扩大；土岩分界面处的注浆体塑性区贯通；基础达到极限承载状态，基础失效。增加锚盘数量和一定范围内增加下部基础的长度会对双锚复合基础的极限抗拔承载力有较大提升；增加锚盘直径和提高注浆体与岩体之间的黏结强度对双锚复合基础的极限抗拔承载力的提升作用不明显；复合基础在弹性模量较大的土体中承载力发挥更充分。

关键词：输电线路基础岩石锚杆螺旋锚抗拔承载力数值分析

Impact of land-use change on hydrological processes in the Maying River basin, China

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Science China Earth Sciences 2006年第10期49卷 1098-1110页

作者： WANG Genxu1,3. ZHANG Yu2, LIU Guimin2 & CHEN Lin3.1. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China 2. Cold and Arid Regions Environmental and engineering Research Institute, Chinese Academy of Sciences, Lanzhou 73.000, China 3. Resource and Environment school, Lanzhou University, Lanzhou 73.000, China 1. Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China 3. Resource and Environment school Lanzhou University Lanzhou 730000 China 2. Cold and Arid Regions Environmental and engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Since the 1960s, dramatic changes have taken place in land-use patterns characterized by the persistent expansion of cultivated land and a continuous decrease in natural woodland and grassland in the arid inland river basins of China. It is very important to assess the effects of such land-use changes on the hydrological processes so vital for water resource management and sustainable development on the catchment scale. The Maying River catchment, a typical arid inland watershed located in the middle of the Hexi Corridor in northwest China, was the site chosen to investigate the hydrological responses to land-use changes. The annual runoff, base flow, maximum peak flow, and typical seasonal runoff in both spring and autumn flood periods were selected as the variables in the hydrological processes. Statistical-trend analysis and curvilinear regression were utilized to detect the trends in hydrological variables while eliminating the climatic influence. The relationship between cultivated land-use and hydrological variables was analyzed based on four periods of land-use variation data collected since 1965. A runoff model was established composed of two factors, i.e., cultivated land use and precipitation. The impact of land use changes, especially in the large ar- eas of upstream woodland and grassland turned into cultivated lands since 1967, has resulted in a mean annual runoff decrease of 28.12%, a base flow decline of 3..3.%, a drop in the maximum peak discharge of 3..77%, and mean discharge decreases in spring and autumn of 3..05% and 24.87% respectively, of which the contribution of cultivated land expansion to the influence of annual runoff amounts to 77%-80%, with the contribution to the influence of spring discharge being 73.-81%, and that to the influence of base flow reaching 62%-65%. Thus, a rational regulation policy of land use patterns is vitally important to the sustainable use of water resources and the proper development of the entire catchment.

关键词： land-use change, arid inland river catchment, hydrological process, impact, Maying River.