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Analysis of Detection and Monitoring Technology in the Construction and Maintenance of Large Bridges
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作者 Shengzhong Xiang Qin Su Shili Zhang 《Journal of Architectural Research and Development》 2024年第3期134-139,共6页
Currently,there is significant attention placed on the construction,management,and maintenance of large service bridges.Within the realm of bridge maintenance management,the utilization of detection and monitoring tec... Currently,there is significant attention placed on the construction,management,and maintenance of large service bridges.Within the realm of bridge maintenance management,the utilization of detection and monitoring technology is indispensable.By employing these technologies,we can effectively identify any structural defects within the bridge,promptly uncover unknown risks,proactively establish maintenance strategies,and prevent the rapid deterioration of bridge conditions.This article aims to explore the advantages of applying bridge monitoring and testing technology and to discuss various methods for implementing detection and monitoring technology throughout the construction,management,and maintenance phases of large bridges.Ultimately,this will contribute to ensuring the safe operation of large bridges. 展开更多
关键词 large bridges construction Maintenance Monitoring technology Detection technology
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Large Dam Construction in China over the Past Fifty Years
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作者 沈崇刚 郑连第 《Electricity》 2000年第4期26-36,共11页
This paper gives an introduction to the large dam construction achievements seen in China over the past fifty years. Four developmental stages, dam height and darn type, newly adopted and developing dam types are elab... This paper gives an introduction to the large dam construction achievements seen in China over the past fifty years. Four developmental stages, dam height and darn type, newly adopted and developing dam types are elaborated in detail, with large dam statistics completed and under construction attached as well. 展开更多
关键词 large dam construction height type statistics
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A SUPERLINEARLY CONVERGENT SPLITTING FEASIBLE SEQUENTIAL QUADRATIC OPTIMIZATION METHOD FOR TWO-BLOCK LARGE-SCALE SMOOTH OPTIMIZATION
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作者 简金宝 张晨 刘鹏杰 《Acta Mathematica Scientia》 SCIE CSCD 2023年第1期1-24,共24页
This paper discusses the two-block large-scale nonconvex optimization problem with general linear constraints.Based on the ideas of splitting and sequential quadratic optimization(SQO),a new feasible descent method fo... This paper discusses the two-block large-scale nonconvex optimization problem with general linear constraints.Based on the ideas of splitting and sequential quadratic optimization(SQO),a new feasible descent method for the discussed problem is proposed.First,we consider the problem of quadratic optimal(QO)approximation associated with the current feasible iteration point,and we split the QO into two small-scale QOs which can be solved in parallel.Second,a feasible descent direction for the problem is obtained and a new SQO-type method is proposed,namely,splitting feasible SQO(SF-SQO)method.Moreover,under suitable conditions,we analyse the global convergence,strong convergence and rate of superlinear convergence of the SF-SQO method.Finally,preliminary numerical experiments regarding the economic dispatch of a power system are carried out,and these show that the SF-SQO method is promising. 展开更多
关键词 large scale optimization two-block smooth optimization splitting method feasible sequential quadratic optimization method superlinear convergence
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3D Model Construction and Ecological Environment Investigation on a Regional Scale Using UAV Remote Sensing
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作者 Chao Chen Yankun Chen +7 位作者 Haohai Jin Li Chen Zhisong Liu Haozhe Sun Junchi Hong Haonan Wang Shiyu Fang Xin Zhang 《Intelligent Automation & Soft Computing》 SCIE 2023年第8期1655-1672,共18页
The acquisition of digital regional-scale information and ecological environmental data has high requirements for structural texture,spatial res-olution,and multiple parameter categories,which is challenging to achiev... The acquisition of digital regional-scale information and ecological environmental data has high requirements for structural texture,spatial res-olution,and multiple parameter categories,which is challenging to achieve using satellite remote sensing.Considering the convenient,facilitative,and flexible characteristics of UAV(unmanned air vehicle)remote sensing tech-nology,this study selects a campus as a typical research area and uses the Pegasus D2000 equipped with a D-MSPC2000 multi-spectral camera and a CAM3000 aerial camera to acquire oblique images and multi-spectral data.Using professional software,including Context Capture,ENVI,and ArcGIS,a 3D(three-dimensional)campus model,a digital orthophoto map,and multi-spectral remote sensing map drawing are realized,and the geometric accuracy of typical feature selection is evaluated.Based on a quantitative remote sensing model,the campus ecological environment assessment is performed from the perspectives of vegetation and water body.The results presented in this study could be of great significance to the scientific management and sustainable development of regional natural resources. 展开更多
关键词 Unmanned air vehicle multi-spectral camera oblique photography 3D model construction ecological environment investigation regional scale
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Constructing Large Scale Cohort for Clinical Study on Heart Failure with Electronic Health Record in Regional Healthcare Platform:Challenges and Strategies in Data Reuse 被引量:2
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作者 Daowen Liu Liqi Lei +1 位作者 Tong Ruan Ping He 《Chinese Medical Sciences Journal》 CAS CSCD 2019年第2期90-102,共13页
Regional healthcare platforms collect clinical data from hospitals in specific areas for the purpose of healthcare management.It is a common requirement to reuse the data for clinical research.However,we have to face ... Regional healthcare platforms collect clinical data from hospitals in specific areas for the purpose of healthcare management.It is a common requirement to reuse the data for clinical research.However,we have to face challenges like the inconsistence of terminology in electronic health records (EHR) and the complexities in data quality and data formats in regional healthcare platform.In this paper,we propose methodology and process on constructing large scale cohorts which forms the basis of causality and comparative effectiveness relationship in epidemiology.We firstly constructed a Chinese terminology knowledge graph to deal with the diversity of vocabularies on regional platform.Secondly,we built special disease case repositories (i.e.,heart failure repository) that utilize the graph to search the related patients and to normalize the data.Based on the requirements of the clinical research which aimed to explore the effectiveness of taking statin on 180-days readmission in patients with heart failure,we built a large-scale retrospective cohort with 29647 cases of heart failure patients from the heart failure repository.After the propensity score matching,the study group (n=6346) and the control group (n=6346) with parallel clinical characteristics were acquired.Logistic regression analysis showed that taking statins had a negative correlation with 180-days readmission in heart failure patients.This paper presents the workflow and application example of big data mining based on regional EHR data. 展开更多
关键词 electronic health RECORDS CLINICAL terminology knowledge graph CLINICAL special disease case REPOSITORY evaluation of data quality large scale COHORT study
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Experimental study on stability of sunken large diameter cylindrical structure on sandy seabed during construction period 被引量:1
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作者 秦崇仁 庞红犁 +1 位作者 李世森 张伟 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2002年第4期581-595,共15页
A systematic experimental research work is done for the stability of sunken large diameter cylinder during construction period. It is the first research that gives the method for assessing the stability of the larger ... A systematic experimental research work is done for the stability of sunken large diameter cylinder during construction period. It is the first research that gives the method for assessing the stability of the larger diameter cylindrical structure, a set of values is derived also for the critical stability indices of the large diameter cylinder sunken to the sandy seabed. 展开更多
关键词 Sunken large diameter cylinder sandy seabed stability during construction period assessing method critical stability index
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Large Scale Fundamental Interactions in the Universe
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作者 Qiao Bi 《Journal of Modern Physics》 2023年第S1期1703-1720,共18页
The author of this paper once attempted to propose a unified framework for gauge fields based on the mathematical and physical picture of the principal fiber bundle: that is, to believe that our universe may have more... The author of this paper once attempted to propose a unified framework for gauge fields based on the mathematical and physical picture of the principal fiber bundle: that is, to believe that our universe may have more fundamental interactions than the four, and these fundamental gauge fields are only components on the bottom manifold (i.e. our universe) projected by a unified gauge potential of the principal fiber bundle manifold;these components can satisfy the transformation of gauge potential, or even be transformed from one basic interaction gauge potential to another basic interaction gauge potential, and can be summarized into a unified equation, namely the generalized gauge equation expression, corresponding to gauge transformation invariance;so the invariance of gauge transformation is a necessary condition for unified field theory, and the four (or more) fundamental interaction fields of the universe are unified in a unified gauge field defined by the connection on the principal fiber bundle. In this paper, the author continues to propose a model of large-scale (gravitational) fundamental interactions in the universe based on the mathematical and physical picture of the principal fiber bundle, attempting to explain that dark matter and dark energy are merely reflections of these gravitational fundamental interactions that deviate in intensity from the gravitational fundamental interactions of the solar system at galaxy scales or some cosmic scales which are much larger than the solar system. All these “gravitational” fundamental interactions originate from the unified gauge field of the universe, namely the connection or curvature on the principal fiber bundle. These interactions are their projected representations on the bottom manifold (i.e. our universe) by different cross-sections (gauge transformations). These projection representations of the universe certainly are described by the generalized gauge equation or curvature similarity equation, and under the guidance of curvature gauge transformation factors, oscillate and evolve between the curvatures 1→0→-1→0→1 of the universe. 展开更多
关键词 Principal Bundle Gauge Similarity Transformation Dark Matter and Dark Energy large-scale Fundamental Interaction Evolution of Universe
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Technical Analysis of Green Construction Management of Large Public Buildings
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作者 Bosong Yi 《Journal of World Architecture》 2020年第5期27-30,共4页
With the development of the times and the improvement of the economic level,the people’s ideological consciousness has gradually changed,driven by the scientific concept of development and the concept of sustainable ... With the development of the times and the improvement of the economic level,the people’s ideological consciousness has gradually changed,driven by the scientific concept of development and the concept of sustainable development,the people have been able to realize that,traditionally,the extensive economic model has led to more serious damage to the environment,and caused a certain degree of resource waste,but also endangered human health.As a result,the concept of healthy living has received more and more widespread attention.The construction industry as an important pillar of China’s economic development,but also the implementation of the concept of sustainable development in China is one of the key points for the implementation of green construction of large public buildings,it is necessary to strengthen the management of technology,so in this paper,will be the main green construction of large public buildings management technology analysis work. 展开更多
关键词 large public buildings Green construction Management techniques
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The Second Large Hydropower Project on Lancana River Starts Construction
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《Electricity》 1997年第3期7-7,共1页
关键词 PROJECT The Second large Hydropower Project on Lancana River Starts construction
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China's Large Dams Construction and Hydropower Development Have a Bright Future──A Summary of talks by authorities concerned on the 20^(th) Congress of International Commission on Large Dams
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《Electricity》 2000年第3期31-33,共3页
关键词 China’s large Dams construction and Hydropower Development Have a Bright Future Congress of International Commission on large Dams th A Summary of talks by authorities concerned on the 20
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Novel process for large scale synthesis of N-(4-hydroxyphenyl) retinamide 被引量:1
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作者 吴晓晴 余佳 吉民 《Journal of Southeast University(English Edition)》 EI CAS 2008年第2期247-249,共3页
A method to synthesize anticancer drug N-( 4- hydroxyphenyl) retinamide (4-HPR)on a large scale is described. It consists of the preferred steps of reacting all-trans retinoic acid with thionyl chloride to form re... A method to synthesize anticancer drug N-( 4- hydroxyphenyl) retinamide (4-HPR)on a large scale is described. It consists of the preferred steps of reacting all-trans retinoic acid with thionyl chloride to form retinoyl chloride and then reacting with triethylamine to generate retinoyl ammonium salt which in turn is reacted with p-aminophenol to eventually produce 4-HPR. This process can overcome many scale-up challenges that exist in the methods reported in the literature and provide an easy, mild and high yield route for large scale synthesis of 4-HPR. Moreover, the effects of the molar ratios of the reagents on the yield are examined. The best molar ratios are a 2.0 molar equivalence of thionyl chloride and a 3.0 molar equivalence of paminophenol to retinoic acid, and the total yield is 80. 7%. 展开更多
关键词 4-HPR large scale SYNTHESIS ANTICANCER
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NEW LIMITED MEMORY SYMMETRIC RANK ONE ALGORITHM FOR LARGE-SCALE UNCONSTRAINED OPTIMIZATION
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作者 刘浩 倪勤 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第3期235-239,共5页
A new limited memory symmetric rank one algorithm is proposed. It combines a modified self-scaled symmetric rank one (SSR1) update with the limited memory and nonmonotone line search technique. In this algorithm, th... A new limited memory symmetric rank one algorithm is proposed. It combines a modified self-scaled symmetric rank one (SSR1) update with the limited memory and nonmonotone line search technique. In this algorithm, the descent search direction is generated by inverse limited memory SSR1 update, thus simplifying the computation. Numerical comparison of the algorithm and the famous limited memory BFGS algorithm is given. Comparison results indicate that the new algorithm can process a kind of large-scale unconstrained optimization problems. 展开更多
关键词 optimization large scale systems symmetric rank one update nonmonotone line search limitedmemory algorithm
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Compact Scanning Tunneling Microscope with Large Scale Searching Capability for Mmultidisciplinary Applications
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作者 孟文杰 王琦 +2 位作者 张晶 侯玉斌 陆轻铀 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第5期523-526,I0001,共5页
We present the design and performance of a home-built scanning tunneling microscope (STM), which is compact (66 mm tall and 25 mm in diameter), yet equipped with a 3D atomic precision piezoelectric motor in which ... We present the design and performance of a home-built scanning tunneling microscope (STM), which is compact (66 mm tall and 25 mm in diameter), yet equipped with a 3D atomic precision piezoelectric motor in which the Z coarse approach relies on a high simplic-ity friction-type walker (of our own invention) driven by an axially cut piezoelectric tube. The walker is vertically inserted in a piezoelectric scanner tube (PST) with its brim laying at on the PST end as the inertial slider (driven by the PST) for the XZ (sample plane) motion. The STM is designed to be capable of searching rare microscopic targets (defects, dopants, boundaries, nano-devices, etc.) in a macroscopic sample area (square millimeters) under extreme conditions (low temperatures, strong magnetic elds, etc.) in which it ts. It gives good atomic resolution images after scanning a highly oriented pyrolytic graphite sample in air at room temperature. 展开更多
关键词 Scanning tunneling microscope large scale searching Air STM Electrochemical STM
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Large Scale Aspects of India-China Summer Monsoon Rainfall 被引量:17
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作者 R. H. Kripalani S. V. Singh 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1993年第1期71-84,共14页
This study investigates the dominant modes of variability in monthly and seasonal rainfall over the India-China region mainly through Empirical Orthogonal Function (EOF) analysis. The EOFs have shown that whereas the ... This study investigates the dominant modes of variability in monthly and seasonal rainfall over the India-China region mainly through Empirical Orthogonal Function (EOF) analysis. The EOFs have shown that whereas the rainfall over India varies as one coherent zone, that over China varies in east-west oriented bands. The influence of this banded structure extends well into India.Relationship of rainfall with large scale parameters such as the subtropical ridge over the Indian and the western Pacific regions, Southern Oscillation, the Northern Hemispheric surface air temperature and stratospheric winds have also been investigated. These results show that the rainfall over the area around 40°N, 110°E over China is highly related with rainfall over India. The subtropical ridge over the Indian region is an important predictor over India as well an over the northern China region. ' 展开更多
关键词 OVER In large scale Aspects of India-China Summer Monsoon Rainfall EOF
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Large Scale VLSI Module Placement Using LFF Heuristics by Stages
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作者 魏少俊 董社勤 +1 位作者 洪先龙 吴有亮 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第5期812-818,共7页
We present a deterministic algorithm for large-scale VLSI module placement. Following the less flexibility first (LFF) principle,we simulate a manual packing process in which the concept of placement by stages is in... We present a deterministic algorithm for large-scale VLSI module placement. Following the less flexibility first (LFF) principle,we simulate a manual packing process in which the concept of placement by stages is introduced to reduce the overall evaluation complexity. The complexity of the proposed algorithm is (N1 + N2 ) × O( n^2 ) + N3× O(n^4lgn) ,where N1, N2 ,and N3 denote the number of modules in each stage, N1 + N2 + N3 = n, and N3〈〈 n. This complexity is much less than the original time complexity of O(n^5lgn). Experimental results indicate that this approach is quite promising. 展开更多
关键词 FLOORPLANNING placements large scale LFF principle deterministic placement algorithm
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Dendritic cells derived from pluripotent stem cells:Potential of large scale production 被引量:5
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作者 Yan Li Meimei Liu Shang-Tian Yang 《World Journal of Stem Cells》 SCIE CAS 2014年第1期1-10,共10页
Human pluripotent stem cells(hPSCs), including human embryonic stem cells and human induced pluripotent stem cells, are promising sources for hematopoietic cells due to their unlimited growth capacity and the pluripot... Human pluripotent stem cells(hPSCs), including human embryonic stem cells and human induced pluripotent stem cells, are promising sources for hematopoietic cells due to their unlimited growth capacity and the pluripotency. Dendritic cells(DCs), the unique immune cells in the hematopoietic system, can be loaded with tumor specific antigen and used as vaccine for cancer immunotherapy. While autologous DCs from peripheral blood are limited in cell number, hPSC-derived DCs provide a novel alternative cell source which has the potential for large scale production. This review summarizes recent advances in differentiating hPSCs to DCs through the intermediate stage of hematopoietic stem cells. Step-wise growth factor induction has been used to derive DCs from hPSCs either in suspension cultureof embryoid bodies(EBs) or in co-culture with stromal cells. To fulfill the clinical potential of the DCs derived from hPSCs, the bioprocess needs to be scaled up to produce a large number of cells economically under tight quality control. This requires the development of novel bioreactor systems combining guided EB-based differentiation with engineered culture environment. Hence, recent progress in using bioreactors for hPSC lineage-specific differentiation is reviewed. In particular, the potential scale up strategies for the multistage DC differentiation and the effect of shear stress on hPSC differentiation in bioreactors are discussed in detail. 展开更多
关键词 PLURIPOTENT stem CELLS DENDRITIC CELLS BIOREACTOR HEMATOPOIETIC differentiation large scale production
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Large scale classification with local diversity AdaBoost SVM algorithm 被引量:5
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作者 Chang Tiantian Liu Hongwei Zhou Shuisheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第6期1344-1350,共7页
Local diversity AdaBoost support vector machine(LDAB-SVM) is proposed for large scale dataset classification problems.The training dataset is split into several blocks firstly, and some models based on these dataset... Local diversity AdaBoost support vector machine(LDAB-SVM) is proposed for large scale dataset classification problems.The training dataset is split into several blocks firstly, and some models based on these dataset blocks are built.In order to obtain a better performance, AdaBoost is used in each model building.In the boosting iteration step, the component learners which have higher diversity and accuracy are collected via the kernel parameters adjusting.Then the local models via voting method are integrated.The experimental study shows that LDAB-SVM can deal with large scale dataset efficiently without reducing the performance of the classifier. 展开更多
关键词 ensemble learning large scale data support vector machine ADABOOST DIVERSITY local.
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Local and global approaches of affinity propagation clustering for large scale data 被引量:15
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作者 Ding-yin XIA Fei WU +1 位作者 Xu-qing ZHAN Yue-ting ZHUANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第10期1373-1381,共9页
Recently a new clustering algorithm called 'affinity propagation' (AP) has been proposed, which efficiently clustered sparsely related data by passing messages between data points. However, we want to cluster ... Recently a new clustering algorithm called 'affinity propagation' (AP) has been proposed, which efficiently clustered sparsely related data by passing messages between data points. However, we want to cluster large scale data where the similarities are not sparse in many cases. This paper presents two variants of AP for grouping large scale data with a dense similarity matrix. The local approach is partition affinity propagation (PAP) and the global method is landmark affinity propagation (LAP). PAP passes messages in the subsets of data first and then merges them as the number of initial step of iterations; it can effectively reduce the number of iterations of clustering. LAP passes messages between the landmark data points first and then clusters non-landmark data points; it is a large global approximation method to speed up clustering. Experiments are conducted on many datasets, such as random data points, manifold subspaces, images of faces and Chinese calligraphy, and the results demonstrate that the two ap-proaches are feasible and practicable. 展开更多
关键词 CLUSTERING Affinity propagation large scale data Partition affinity propagation Landmark affinity propagation
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A LIMITED MEMORY QUASI-NEWTON METHOD FOR LARGE SCALE PROBLEM 被引量:3
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作者 邓卫兵 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1996年第1期71-79,共9页
We study how to use the SR1 update to realize minimization methods for problems where the storage is critical. We give an update formula which generates matrices using information from the last m iterations. The numer... We study how to use the SR1 update to realize minimization methods for problems where the storage is critical. We give an update formula which generates matrices using information from the last m iterations. The numerical tests show that the method is efficent. 展开更多
关键词 large scale PROBLEM LIMITED MEMORY methods SR1 formula.
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Comparing the reinforcement capacity of welded steel mesh and a thin spray-on liner using large scale laboratory tests 被引量:7
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作者 Zhenjun Shan Porter Ian +1 位作者 Nemcik Jan Baafi Ernest 《International Journal of Mining Science and Technology》 SCIE EI 2014年第3期373-377,共5页
Steel mesh is used as a passive skin confinement medium to supplement the active support provided by rock bolts for roof and rib control in underground coal mines. Thin spray-on liners(TSL) are believed to have the po... Steel mesh is used as a passive skin confinement medium to supplement the active support provided by rock bolts for roof and rib control in underground coal mines. Thin spray-on liners(TSL) are believed to have the potential to take the place of steel mesh as the skin confinement medium in underground mines.To confirm this belief, large scale laboratory experiments were conducted to compare the behaviour of welded steel mesh and a TSL, when used in conjunction with rock bolts, in reinforcing strata with weak bedding planes and strata prone to guttering, two common rock conditions which exist in coal mines. It was found that while the peak load taken by the simulated rock mass with weak bedding planes acting as the control sample(no skin confinement) was 2494 kN, the corresponding value of the sample with 5 mm thick TSL reinforcement reached 2856 kN. The peak load of the steel mesh reinforced sample was only2321 kN, but this was attributed to the fact that one of the rock bolts broke during the test. The TSL reinforced sample had a similar post-yield behaviour as the steel mesh reinforced one. The results of the large scale guttering test indicated that a TSL is better than steel mesh in restricting rock movement and thus inhibiting the formation of gutters in the roof. 展开更多
关键词 Steel mesh Thin spray-on liners large scale laboratory experiments Strata with weak bedding planes Strata prone to guttering
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