bluuebunny/crossref_metadata_2025 huggingface dataset:
Hailstone Classifier Based on Back Propagation Neural Network
Authors: Liu Xiang Yang , Wan Hui Song , Zhang Yuan Yuan , Jiang Shu Ming
Published: October 2013

The Back Propagation (BP) neural network was used for the construction of the hailstone classifier. Firstly, the database of the radar image feature was constructed. Through the image processing, the color, texture, shape and other dimensional features should be extracted and saved as the characteristic database to provide data support for the follow-up work. Secondly, Through the BP neural network, a machine for hail classifications can be built to achieve the hail samples auto-classification.
The Design and Modeling of Jetting Dispenser Actuated by Dual Piezostack Actuator
Authors: Jeon Jun Cheol , Nguyen Quoc Hung , Choi Seung Bok
Published: October 2013

This article presents performance results of a novel jetting dispenser system actuated dual piezostack actuators. The proposed piezo jetting dispenser system consists of a couple of piezostack actuators, lever mechanism, and needle part. The proposed dispenser can provide a very small dispensing dot size of high viscous adhesive, 10,000cp at 100°C, at a high dispensing flow rate in semi-conductor packaging processes. After describing the mechanism and operating principle of the proposed dispenser, a mathematical model of the system is obtained by considering behaviors of the piezostack, the return spring, the dispensing needle, and the adhesive fluid dynamics. For the computer simulation, the specific geometric dimensions of the proposed jetting dispenser are chosen in order to achieve operation requirements: needle motion amplitude: up to 0.15 mm; operating frequency: up to 500 Hz. With the high viscosity conditions, the dispensed amount of the adhesive and the maximum displacement of the piezo and the needle at 500Hz are evaluated in time domain.
An Empirical Analysis of Similarity Matrix for Spectral Clustering
Authors: Zhang Sheng , He Xiao Qi , Liu Yang Guang , Huang Qi Chun
Published: October 2013

Constructing the similarity matrix is the key step for spectral clustering, and its goal is to model the local neighborhood relationships between the data points. In order to evaluate the influence of similarity matrix on performance of the different spectral clustering algorithms and find the rules on how to construct an appropriate similarity matrix, a system empirical study was carried out. In the study, six recently proposed spectral clustering algorithms were selected as evaluation object, and normalized mutual information, F-measures and Rand Index were used as evaluation metrics. Then experiments were carried out on eight synthetic datasets and eleven real word datasets respectively. The experimental results show that with multiple metrics the results are more comprehensive and confident, and the comprehensive performance of locality spectral clustering algorithm is better than other five algorithms on synthetic datasets and real word datasets.
The Research of Power Battery SOC Estimation Based on Adaptive Kalman Filter Algorithm
Authors: Yu Wei Bo , Yang Ting Ting , Feng Cui Yuan , Li Hong Jun
Published: October 2013

Taking the lithium iron phosphate power battery as the research object, through analysis on characteristics of the battery, this paper chooses the improved second-order RC model as the model of battery whose complexity is moderate and it can better reflect the battery dynamic and static characteristics. Then by pulse discharge experiments and with improved recursive least squares algorithm to identify model parameters online, and puts forward up the adaptive kalman filtering algorithm to estimate battery SOC. The results show that the adaptive kalman filter algorithm can effectively improve battery SOC estimation precision.
Multi-Device Health Management Based on Elman Neural Network
Authors: Gao Lei , Li Jing , Zou Jin Long , Sun Fa Yu , Lei Zhi Yong
Published: October 2013

For fault forecast and information exchange problems in multi-device health management, the paper proposed a multi-device and multi-parameter fault forecast technology based on Internet of Things, and improved fault prediction algorithm based on Elman neural network feedback. Therefore, it can implement approximating nonlinear functions by arbitrary accuracy, and use the feedback reference to historical data. Thereby, it can provide early detection, isolation, management and forecasting for component failure warning, the initial issuance of the fault condition and ancillary component failure and other states multi-device health management. It also improves self-learning and adaptive capacity of the system, and effectively improves the robustness of the fault prediction system.
Real-Time Monitoring of Degradation of Zirconia Ceramic by Acoustic Emission
Authors: Wu Kai Ge , Choe Chan Yang , Lee Seung Mi , Yoo Ji Ae , Hyun Chang Yong , Hong Dong Pyo , Byeon Jai Won
Published: October 2013

Acoustic emission (AE) technique was employed to monitor the low temperature degradation (LTD) behavior of a zirconia ceramic, which was carried out in air at 200°C. AE signals, typical waveform of which exhibited as pulse-like type, were detected during LTD and increased with the duration time of LTD. The AE signal of accumulative counts number and amplitude in time domain exhibited a roughly sigmoid variation including three stages, which reflect approximately the evolution of LTD. The AE findings were supported by X-ray diffraction (XRD) examination. It was suggested that AE technique can be used to monitor the mechanism of LTD of zirconia ceramics.
Research of Spectrum Detecting Technology on Cognitive Radio
Authors: Mao Hong Yan
Published: October 2013

Cognitive radio (CR) is an intelligent spectrum sharing technology. It can improve the spectrum utilization by sensing spectrum environment, learning intelligently and adjusting the transmission parameters. The discussion is focused on spectrum detecting technology in cognitive radio. Spectrum detecting algorithms are analyzed and compared .The centralized cooperative spectrum detection method, distributed cooperative spectrum sensing method and relay cooperative spectrum detection method are analyzed also.
Research on Key Technology of Cold-Rolled Aluminum Plate Surface Defect Detection System
Authors: Zhang Hai Lun , Qi Xing Guang , Li Xiao Ting
Published: October 2013

This paper presents the research of several key technologies during the implementation of cold-rolling aluminum surface defect detection system, including the difficulty of achieving these key technologies and the improvement of image processing algorithm. Through the installation and commissioning on actual production line, summarize and analyze the requirements of the hardware and software design for highly reflective aluminum plate, to achieve the control of product quality at present.
Review of Techniques for Driver Fatigue Detection
Authors: Zhang Jian Yong , Qiu Wen Wei , Fu Hui Jian , Zhang Meng Ting , Ma Qing Guo
Published: October 2013

Driver fatigue is a significant issue in driving safety. Large bodies of literature have examined fatigue detection methods and techniques. This paper provides a broad overview of the researches concerning related topics. So far, driver fatigue detection techniques developed can be divided into three categories, including techniques based on vehicle movement tracking, drivers behavioral features and electroencephalograph signals. In addition, a contrast between these techniques was presented and further researches were discussed.
A Collision Detection Algorithm Based on Spatial Partitioning and Bounding Volume
Authors: Zhao Wei , Ye Li Ming
Published: October 2013

In order to improve the real-time and accuracy in the collision detection technology, a collision detection algorithm based on spatial partitioning and bounding volume was proposed . This algorithm adopted different spatial division strategies for different locations of the spaces according to the details in the scenes to exclude objects which can not intersect.Thus defined the potential intersection areas. Then we used a dynamic S-AABB hierarchy bounding boxes to test whether the intersection happened between the objects in the same grids. We used the sphere boxes to rule out the disjoint objects quickly. Then constructed the dynamic AABB bounding boxes trees for the rest of objects for further intersection test. At last, we improved the traditional overlapping test between the primitives for accurate collision detection . Compared to the traditional collision detection algorithm based on spatial partitioning and AABB bounding volume. This algorithm effectively improves the real-time of the collision detection without affecting the accuracy of original collision detection.
Electromagnetic Interference Testing and Suppression Methods for Automotive Window Lifter Motor
Authors: Hou Qun , Jin Ya Ping , Zhou Yi Fan
Published: October 2013

Window lifter motor is one of the potential electromagnetic interference (EMI) sources in automobile. Based on the research on the principle of Window lifter motor and the generation mechanism of EMI, its EMI characteristics are tested and analyzed. The EMI suppression methods are proposed. By comparing two filters methods,it shows that the designed filter suppresses the electromagnetic interference more effectively. Its conducted emission and radiated emission are lower than the second lever limits of CISPR 25-2007+.
An Improved Passive Anti-Islanding Technique for Distributed-Generation Photovoltaic Systems
Authors: Zhang Shao Ru , Li Shao Yuan
Published: October 2013

Islanding detection techniques for DGPV are employed in order to determine the status of the electrical grid. In fact, the grid-connected inverter must be stopped once the islanding operating mode is detected according to standards and grid-code limits. Passive anti-islanding techniques monitor grid parameters to detect islanding. One advantage of passive techniques is a lower THD injected into the grid by active techniques. Thus, passive techniques were studied and an improved passive detection technique was proposed in this paper. The ratio of phase variation and the voltage variation at the point of common coupling (PCC) was adopted to detect islanding. In addition, this method combined with the under/over voltage detection and the under/over frequency detection. Then, the proposed technique not only has the merit of low cost and easy to operate, but also has multiple judgment and high reliability. The simulation results under Matlab/Simulink show that the proposed technique is very effective in reducing the non-detection zone and that the islanding operation can be detected more rapidly and effectively than traditional passive techniques, and that it can not misjudge when the load reduce suddenly.
Analysis and Field Test about Operation Ventilation Effect of Dabieshan Highway Tunnel
Authors: Xia Feng Yong , Wang Ya Qiong , Jiang Xue Meng
Published: October 2013

Twin tubes complementary ventilation technology was applied in Dabieshan highway tunnel for the first time in domestic. Based on test of the amount of carbon monoxide, smoke concentration and wind velocity, and analysis of the data, it is concluded that the twin tubes complementary ventilation technology is workable and reliable. In addition, the results provide the reference for the ventilation monitoring of Dabieshan tunnel and also for the technical guidance of ventilation mode in the later similar engineering design.
Decision Evaluation of Harbin Metro Based on Fuzzy Theory
Authors: Chen Xiao Guo
Published: October 2013

The paper introduces some information about Harbin Metro line 1, makes the decision analysis on economies, environment, society and geological environment of Harbin Metro line 1 by some fuzzy comprehensive evaluation model, and gives the weight coefficients of indicators through analytic hierarchy process. The comprehensive evaluation result provides the basis for decision-makers during decision of metro projects.
Improved Model of Metro Segment Liner Endogenetic Forces
Authors: Yang Yue , Chen Xiao Guo
Published: October 2013

Harbin metro, the first engineering is in the process of being built. Metro tunnel is supported by reinforced concrete structure. Commonly used model is used in design of shield tunnel liner. In this paper, the habitual model is improved. The joint of model of the habitual model is improved and the endogenetic force formulas for the new model are derived. At last, the derived formulas and the existing formulas are validated by Harbin first metro. According to the research result, we can know the formulas derived in the paper are credible and they have academic practical meaning for design and construction of the subway liner.
A Nonlinear Viscoelastic Rheological Model of Soft Soil Based on Fractional Order Derivative
Authors: Li Rui Duo , Yue Jin Chao , Zhu Cun Zhen , Sun Zhen Yang
Published: October 2013

In order to overcome the defects of the classical model in the description of the rheological properties of soft soil, an Abel glue pot was defined based on the fractional derivative theory by the fractional calculus of Riemann-Liouville. Three components fractional order derivative solid model was built with Abel glue pot. Then the experimental data was fit using the new model. The simulation results show that the three components fractional order derivative solid model is more accurately than the generalized Kelvin model or Burgers model and that it has few parameters.
Comparison of Seismic Design Schemes for Suspension Bridge in Mountain Region with Strong Earthquake
Authors: Wu Gui Lin , Yang Qian Jiang , Gao Wen Jun
Published: October 2013

The Longjiang Bridge is a kilometer level suspension bridge supported by reinforced concrete towers. The towers will be founded on pile group foundation, and the project area is in a mountain region of high earthquake probability. Two seismic schemes were designed for the bridge, and two computational bridge models in full size were established, extensive studies were performed to capture the seismic response of different schemes for the earthquakes. The results show that towers composed of two curved quadrilateral hollow concrete columns are adopted for the bridge.
Study on Spatial Effect of Wide Box Girders under Unbalance Loading
Authors: Chen Ke , Wang Lei
Published: October 2013

Prestressed concrete continuous wide box girder bridge is widely used in urban bridges, because of its large width-span ratio, spatial effects from unbalance load cannot be ignored. When the bridge was analyzed by beam element system, the increased coefficient of unbalance loading is used to simplified space problem into plane problem. Spatial effect of wide box girder under unbalance loading is calculated by solid finite element method, and used in a project example in Hangzhou. Comparing analysis results of solid finite element with other simplified methods, it shows that the solid element method is more applicable and accurate. This method and results offer reference for similar bridge design calculation.
Stability Control of Continuous Compaction Measurement in High-Speed Railway Subgrade
Authors: Jiao Tan , Wang Xiang , Huang Ya Bing
Published: October 2013

The compaction stability is of great significant for the quality control and assurance of the continuous compaction measurement in subgrade engineering. Based on the mean-variation method, the exponential function between the roller passes and the roller measurement value was modeled to calculate the compaction stability index Δμtmv. The stabilization process of the compacted soil from loose state to dense state could be well described by the modeled function. Through the results of the roller measurement values in three test field of Shanghai-kunming high-speed rail in Huaihua, Zhijiang and Loudi, different compaction stability index due to the varied construction situations was calculated using the mean-variation method and the exponential function. The result shows that the exponential function is well adaptive to different situations and this method could be developed in controlling the stability of continuous compaction measurement.
Simulation Study of Stability of the Transmission Tower Foundations on Mined-Out Area
Authors: Li Zhao Guang , Sui Zhi Li , Li Wen Li , Sun Xin Shuo , Xu Tie Jun
Published: October 2013

As more and more electric transmission lines have to go through the mining area, if we can fully realize the collapse and deformation characteristics of mined-out area, and master the scientific laws of its occurrence and development, we may take reasonable measures to avoid the happening of accidents, ensure the line to run in a reliable way, and greatly improve the construction quality and economic benefits. For different location conditions of coal mine worked out section to the surface of the power transmission tower, we use finite difference software FLAC3D to analyze mutual influence and interaction between underground worked out section and surface iron tower foundation. The conclusion in this paper can be used as a reference to mining site. The influence range can be estimated before mining, as far as possible avoiding influence within the scope of strata. It is the key to ensure the safety of power transmission tower, people life and property.
Research on Bolt Vibration Rule under Axial Dynamic Load
Authors: Bao Xian Kai , Li Yi
Published: October 2013

We obtain response regularity of stress wave in bolt, which regularity can be applied in nondestructive testing of anchoring quality, with establishing longitudinal one-dimensional bolt wave equation, studying longitudinal vibration responses under several boundary conditions by the principle theory of elastokinetics. And it is the principal theory that anchoring quality is deduced by bolt vibration response which is caused by dynamic transient vibration.
Feasibility Study of Passive Electromagnetic Dampers for Vibration Control of Stay Cables
Authors: Wang Zhi Hao , Hua Guang Ping
Published: October 2013

Effective vibration control technology for stay cables is extremely critical to safe operations of cable-stayed bridges. This paper focuses on a new cable vibration control technology and introduces an electromagnetic damper being tested for its electrical performance. Control performance of a model cable attached with a passive electromagnetic damper was investigated in the laboratory. The test results show that modal damping ratios of the cable in the first four modes can be improved significantly with the electromagnetic damper. As such, advantages and feasibilities of this new cable vibration controlling system are finally demonstrated.
Simulated Environment Test on Weather Fastness of Fair-Faced Concrete for Urban Bridge
Authors: Zhang Xiao Yan , Ma Xiao Lu , Jin Li Hui , Li Xiao Ke
Published: October 2013

To keep the perfect, artistic and natural characteristics of fair-faced concrete, it is necessary realizing its weather fastness. This paper introduces the simulated environment test for weather fastness of fair-faced concrete considering the environmental actions at all seasons such as washing of acid rain, sand blown by the wind, exposure to blazing sunlight, salt-fog, carbonization and freeze-thaw. Test methods for sand blown by the wind, washing of acid rain, slow freeze-thaw and exposure to blazing sunlight were invented. The mass change of concrete were measured, and the surface quality was evaluated by the glossiness, the pixel difference and the variance of pixel difference. The results showed that the mass had a little change under the comprehensive actions. The factors decreasing the surface quality in sequence from serious to slight were the washing of acid rain, the salt-fog, the freeze-thaw and the carbonization. The erosion degree increased with the increasing pH value in rainwater and the increasing density of sulfate-ion in salt-fog solution. The surface of concrete damaged by the long-term freeze-thaw and carbonization. The sand blown by the wind, and the exposure to blazing sunlight had little influence on the surface of concrete.
Experimental Study on Basic Properties of Fair-Faced Concrete for Urban Bridge
Authors: Jin Li Hui , Ma Xiao Lu , Li Xiao Ke
Published: October 2013

As the high-performance concrete with remarkable characteristics of artistic presentation and ecological sense, fair-faced concrete is becoming more and more attention by the department of urban construction. As part of the research project, this paper gives the supplement study of the mix proportion and basic properties of C50 fair-faced concrete, and summarizes the experimental results of the apparent quality of C30 and C50 fair-faced concrete affected by the mold releases. Considering the parameters of water to cement ratio, cement dosage, percent of pulverized fly ash, sand ratio, water reducer and mold releases, the workability of fresh concrete and the compressive strength of hardened concrete at 7 days, 28 days and 56 days, as well as the apparent quality and surface brightness were measured, the mix proportions of C30 and C50 fair-faced concretes for construction of urban bridge were determined. Based on the measurements of surface brightness, color uniformity, resistance to water penetration, stain resistance and compressive strength of fair-faced concrete, the formwork lacker can be firstly selected as the mold release, and the mix oil (diesel: machine oil=3:7) can be the alternative selection.
Application of Genetic Arithmetic and Support Vector Machine in Prediction of Compression Index of Clay
Authors: Shi Xu Chao , Gao Ying Fei
Published: October 2013

The compression index is an important soil property that is essential to many geotechnical designs. As the determination of the compression index from consolidation tests is relatively time-consuming. Support Vector Machine (SVM) is a statistical learning theory based on a structural risk minimization principle that minimizes both error and weight terms. Considering the fact that parameters in SVM model are difficult to be decided, a genetic SVM was presented in which the parameters in SVM method are optimized by Genetic Algorithm (GA). Taking plasticity index, water content, void ration and density of soil as primary influence factors, the prediction model of compression index based on GA-SVM approach was obtained. The results of this study showed that the GA-SVM approach has the potential to be a practical tool for predicting compression index of soil.
Study of Soil Liquefaction Analysis Based on the P-Z Model
Authors: Zhang Hong Yang , Zhang Xian Qi , Yao Meng , Yao Liang
Published: October 2013

Dynamic constitutive models and liquefaction characteristics of soil are critical in the seismic stability analysis on embankment dams. The P-Z constitutive model, which is a kind of the multi-mechanism plastic model based on generalized plasticity, is mainly introduced in this paper. Considering soil as two-phase media, based on the Biot fluctuation theory and the P-Z model, the dynamic analysis formulation of two-phase media is established, and the criterion of soil liquefaction is proposed through investigations, where the generation and dissipation process of soil pore pressure and the variations of effective stress are taken into account. Furthermore, the interface conditions between two-phase media and the other types of medium are derived and the examples of verification are presented.
A Study on Relationship of Landslide Occurrence and Rainfall
Authors: Wang Hui , Zhang Yu Cheng , Hu Hai Ying
Published: October 2013

Based on the analysis of geological data and meteorological data of landslide, the mechanism of rainfall-induced landslides was analyzed, and the relationship between landslide and rainfall was further discussed, including the landslides and rainfall distribution, the relationship between landslide and frequency of rainstorm, and the time relationship between landslide and rainfall. The results show that the probability of landslide occurrence and the quantity of landslides have positive correlation with rainfall. The landslides mainly occur from May to September in which the monthly mean rainfall is large. Meanwhile, landslide occurrence is closely related to the characteristics of rainfall of that day and rainfall of early days. When the daily rainfall exceeds 50mm or 10 days accumulative rainfall exceeds 100mm, the landslide is prone to occur and the occurrence rate of the latter is higher.
Analysis of Protection Engineering for High Slope in Western Henan Province
Authors: Ding Shu Yun , Bi Qing Tao , Wu Qi
Published: October 2013

Multistage discharge gentle slope combined with wide platform was adopted in the protection for high slope of highway in loess area, but vertical slope was often adopted at construction engineering of high slope as there was no enough site space for step-slope under the construction of urbanization in the western loess region of Henan province. A typical loess high slope in Lingbao city was taken to discuss the prevention measures for upright loess high slope. Design parameters for slope protection was given in detail, approach on the control plan for deformation has both excavation slope of 35m high and fill slope of 30m high. While reinforcement scheme of anchor cable plus stiffened-cylindrical was used in slope protection, the reinforced retaining wall was used to support the filling slope, in addition, loess slope management must be prepared to slope drainage design and construction.
Experimental Study on Anti-Permeability of Active Admixture Recycled-Concrete
Authors: Chen Ai Jiu , Sun Xiao Pei , Yang Fen
Published: October 2013

Active admixture recycled-concrete (AARC) is one of green high performance concretes, which took active admixture and fly ash into recycled concrete to replace part of cement. This paper researches the relationship of seepage resistance grade and chloride diffusion coefficient of recycled concrete by the regressive analysis of experimental data from NEL and gradually pressure method. The mufti-factor (slag powder, fly ash, air-entraining agent, polypropylene fiber, recycled coarse aggregate) and multi-level experiments of anti-permeability of concrete were carried out by orthogonal experiment method, and the optimum proportion of concrete is determined. The results show that seepage resistance grade of 16 groups AARC all reached W13, and chloride diffusion coefficient was between 0.5~1×10-8cm2/s, the permeability grade is IV. The impermeability of the AARC is excellent. The rate of recycled coarse aggregate and slag powder were the most important factors for the impermeability properties of concrete, the optimum proportion of concrete was 10% slag powder, 20% fly ash, 1/10000 air-entraining agent, 1.0 kg/m3 polypropylene fiber and 40% recycled coarse aggregate.
Research on Support Technique for Excavation Process of Deep Rock Mass
Authors: Wu Hong Xiao , Yue Song Lin , Shi Cun Cheng , Hu Xiao , Chu Cheng , Zhang Wei
Published: October 2013

In the deep rock mass surrounding, rock burst, large deformation, zonal fracturing and phenomena like these may occur in the tunnel excavation process. When zonal fracturing happens, it is essential to reconsider the types of support, the boundary of support and the approach of tunnel excavation. In this paper, the control theory about the surrounding rock stability under high pre-existing stresses was researched, and the efficient support form which was the combination of high strength anchor bar and anchor cable was ascertained to be adaptive to deep tunnel excavation. According to the deformation and zonal fracturing mechanism of the surrounding rock, a comprehensive support program that combined intensive short anchor bars and long anchor cables was established, and the numerical simulation was carried out to verify the feasibility of the support form.
Analyze the Impact of the Thin-Walled Hollow Pier by Construction of Reservoir
Authors: Tang Ke Dong , Jin Feng Gui
Published: October 2013

The river dam intends to build at 280m downstream of a built bridge. This paper, using ANSYS finite element software, establishes a rational and realistic model to analyze the influence of the reservoir construction on the thin-walled hollow pier of built bridge. The variation of the stress of the bridge thin-walled hollow pier before and after impounding of the reservoir is given out, which can be as a guidance for future reinforcing the thin-walled hollow pier.
Establishment of Constructional Quality of Engineering Check and Evaluation Index System for Dike of Yangtze River
Authors: Wang Li , Guo Hui , Li Xiaoe
Published: October 2013

To promote the preparation of technical standards for the quality of detection and evaluation work of the Yangtze River Dike reinforcement project completion and acceptance, this paper summarizes the quality check method of reinforcement works of the main dyke of Yangtze River. In the combination of the standard, design document and practical working condition, the quality check and evaluation index system for different construction contents are put forward. To promote the quality assessment of Yangtze River Dike project completion, comprehensive evaluation index system of quality inspection is established.
Effect of Confluence Ratio Change on Hydrodynamic Character in Reservoir Area
Authors: Yan Tao , Chen Li , Duan Tao , Zhou Min
Published: October 2013

Major factors that affect hydrodynamic character include confluence ratio, junction angle, bed discordance and channel gradient. In reservoir area, the river confluence is also affected by change of water level results from impoundment. Focused on asymmetrical confluence with 90° junction angle in reservoir area and based on model test, velocity distribution, location and range of reverse flow zone under different confluence ratios and water levels were investigated. The results show that flow velocity always declined along the channel after convergence. When confluence ratio increased, velocity decline rate accelerated, tributary flow diffused more fiercely at the conflux section, reverse flow zone enlarged. As the water level rising up, overall flow field velocity was weakened, the degree of tributary deflection increased. The velocity declined much slower in high water level.
Engineering Advice for Preventing Crack on the Upstream Surface of Super-High Arch Dam
Authors: Guan Jun Feng , Qing Long Bang , Bai Wei Feng , Wang Juan , Lin Peng
Published: October 2013

In this paper, the crack stability and crack propagation regularity of the upstream surface of super-high arch dam along the water-stop structure were analyzed in the framework of fracture mechanics. According to fracture toughness of dam concrete, the relationship between the crack propagation length and the allowable water pressure was studied. Finally, two main specific engineering suggestions for avoiding this kind of crack on the upstream surface of super-high arch dam were given: (1) the value of checking water pressure should not exceed 0.4 MPa; (2) the flange of the water-stop structure near the upstream surface of dam should be changed toward the downstream.
A Real-Time ZigBee-Based Location System in Xiluodu Arch Dam
Authors: Lin Peng , Guan Jun Feng , Li Qing Bin
Published: October 2013

This study main focuses on a real-time Zigbee-based localization system to provide prompt support for safety management in dam construction sites. The system accounts for a wireless sensor tracking technology and a set of servers running software for handling collected data, real-time site state visualization and remote interaction communications with other system such as ERP, CRM. The low-level tracking technology is a ZigBee-based network hardware utilizing fingerprinting software technology. The proposed real-time monitoring system for employer has been successfully implemented in Xiluodu arch dam construction site. The field tests also show that the RSSI-based localization algorithm implemented by ZigBee devices is reliable and is accurate (3 to 5 meters) enough. This real-time monitoring system was proven to be very useful for field safety management of high arch dam, and in similar hydraulic projects.
Research on the Correlation between Autoclam Permeability Test and Seepage Height Method
Authors: Hao Ting Yu , Wu Zhi Gang , Bai Yun , Basheer P.A.M.
Published: October 2013

By comparing the permeability test results between the autoclam method introduced by Queens University Belfast and the seepage method specified in China standard, it was found that water permeability index given by autoclam test had a better correlation with seepage value than air permeability index and water absorption index.
Clay Compaction Test for the Core Wall of DJIPLOHO Dam
Authors: Liu Jun
Published: October 2013

The earth-rock dam on left bank of the head of DJIPLOHO Hydroelectric Power Station adopts the clay core dam. Due to the tropical oceanic climate which is hot and rainy, the soil of clay core wall has high water content. Through the compaction experiment on site, it chooses suitable dry density, formulates reasonable rolling parameters and finally achieves good construction quality, which ensures the construction progress and meets the requirement of engineering. This accumulates valuable experience for the design and construction of same types engineering.
Multi-Criteria Evaluation of the Scheduling of a Hydrothermal Power System Using Analytic Hierarchy Process
Authors: Yu Xiang , Zhang Xue Qing
Published: October 2013

The scheduling of a hydrothermal power system needs to take into account multiple economic, social and environmental criteria, such as power production, flood protection and control, water supply for agricultural, industrial and domestic uses, navigation, water quality control, ecological environment protection, fishery, recreation, and pollutant emission control. In addition, determination of the scheduling must involve the participation of various stakeholders. Hence, this paper proposes a framework for multi-criteria evaluation of the scheduling of a hydrothermal power system based on group decision making using analytic hierarchy process (AHP). The AHP is used to select a balanced scheduling scheme out of a number of alternatives through performing pairwise comparisons according to judgments of the decision group members.
Test Study of Influence of Fine Particle Content on Creep Property of Sandy Slate Coarse-Grained Soil
Authors: Jia Li Hao , Deng Xiang Bo , Jiang Man
Published: October 2013

Creep property of coarse-grained soil is an important property influencing long-term settlement of embankment. Based on the H-K creep model which is consistent with the experimental results and verified by uniaxial compression creep test, relationship between fine grain composition and creep parameter and pattern of creep property of sandy slate coarse-grained soil influenced by fine grain composition are studied. It turns out that fine particle content is the important factor that affects creep property of sandy slate coarse-grained soil and using fine particle content of 30% is able to decrease long-term settlement of embankment.
Stability Analysis and Evaluation of QingXi High-Cutting Slope
Authors: He Jian Ping , Wang Ya Li
Published: October 2013

Rock nature is mainly controlled by joint-fissur, the stability of rock slope is mainly controlled by the joint surface, the destruction of the slope caused wedge instability formed by joint plane cutting. Stereographic projection can analyze simply and intuitively spatial association relations of straight line and plane in geological body, judge high-cutting slope stability and decisive factor of judge stability of high-cutting slope by means of direction and tendency relationship of rock slope and structural plane. This paper uses stereographic projection to analyze and judge high-cutting slope stability formed by artificial mechanical excavation in Qingxi, and decisive factor of stability according to deformation and fracture and the trends in the high-cutting slope regional, puts forward the high-cutting slope control measures and methods to ensure slope stability and security.
Application of LS-SVM to Prediction of Bearing Capacity of Cement-Flyash-Gravel Pile Composite Foundation
Authors: Ding Wei , Liu Qing , Sun Kang Kang , Sui Feng Tao
Published: October 2013

There are a lot of factors that influence the bearing capacity of composite foundation, and the relationship between them is complex and nonlinear. Based on study of main factors that have great influence on bearing capacity of cement-flyash-gravel (CFG) pile composite foundation, the least squares support vector machine (LS-SVM) model of bearing capacity of composite foundation was established. The results show that the model has excellent learning ability and generalization and can provide accurate data prediction only with fewer observed sample. It is proved that the new method is a promising method for the determination of bearing capacity of CFG pile and other rigid piles composite foundation.
Water-Saving Irrigation and Food Security in China
Authors: Liu Xiao Fei , Xu Jian Xin , Sun Jing Sheng , Fei Liang Jun , Zhang Ji Yang , Shen Xiao Jun , Chen Zhi Fang
Published: October 2013

With the growth of population, shortage of water resources, natural disasters, climate change, serious shortage of land resources and the development of urbanization and industrialization and impacts of other unfavorable factors, China's grain security issue has become a focus of public concern. Through the Chinese population quantity analysis and forecast of 2020 and 2030 the total demand of grain, comparison between total demand and current level of food production, China's grain problem is facing tremendous pressure. Water conservancy is the lifeline of agriculture and irrigation has great potential for grain production guarantee. Results for food safety in China made the following responses: First, the rational use of water resources, improve the efficiency of irrigation and grain yield per unit area. Second, multiple sectors such as agriculture, meteorology, soil, make a good combination of multiple disciplines for food security. Third, increase the peasants' production enthusiasm. Last, scientific and technological progress is the guarantee of grain production. In General, the issue of food security is national security, social stability, a top priority. The combination of our country's water resources crisis, limited rational development of agricultural water resources, improve the efficiency of irrigation, which will provide a guarantee for China agricultural water crisis, alleviating the shortage of water resources and increasing food safety assurance.
Influence on Permeability and Mechanical Properties of Pervious Concrete by Aggregate Gradation
Authors: Zhang Xiao Yan , Liang Na
Published: October 2013

The skeleton of concrete is determined by aggregate gradation. This paper studies the permeability and mechanical properties of pervious concrete affected by the aggregate gradation. Eight levels of aggregate gradation were selected, which included the single grain grading, double size grain grading and continuous grading. It is found that by series of tests, compared to the pervious concrete with the single grain grading and double size grain grading, the pervious concrete with continuous grading has low porosity, small permeability coefficient, high cubic compressive strength and similar splitting tensile strength and the flexural strength.
Seismic Behavior and Performance-Based Design of Resilient Concrete Columns
Authors: Sun Yu Ping , Cai Gao Chuang , Takeshi Takeuchi
Published: October 2013

We proposed a new type of aggressive concrete structure in this paper. The proposed structure consists of concrete columns reinforced by ultra-high strength rebar with spiral groove on its surface. Four circular concrete columns were fabricated and tested under cyclic reversed lateral force and constant compression to investigate the seismic behavior of the proposed columns. Test results have shown that the concrete column had high resilience, and use of the ultra-high strength rebar with spiral groove on its surface could significantly mitigate damage degree and reduce residual deformation of concrete column. Based on the experimental results, we developed a model to simulate the hysteresis loop of the proposed resilient column and an equation to assess the equivalent viscous damping ratio, which was indispensable to performance-based design of the resilient column. Very good agreement was observed between the measured results and the theoretical predictions.
Seismic Performance of Prestressed Reinforced Concrete Piles Reinforced with Nonprestressed Reinforcements
Authors: Wang Tie Cheng , Wang Wen Jin , Zhao Hai Long , Yang Zhi Jian
Published: October 2013

The main purpose of this paper is to study the seismic performance of prestressed reinforced concrete pile (PRC pile) reinforced with nonprestressed reinforcements. Two prestressed high strength concrete piles (PHC piles) and two PRC piles were tested. The variables studied in this research are the prestressed reinforcements ratio and nonprestressed reinforcements ratio. The piles subjected to low-cycle loading were presented in this paper, including the hysteretic performance, stiffness degradation curves, coefficient of equivalent viscous damping and skeleton-frame curves. It is shown that the failure modes of all specimens are bending damage from the test and PRC piles have good energy-absorbing hysteretic behavior.
Seismic Performance Experimental Research on the Multi-Ribbed Composite Wall-Transfer Layer Supported on Frame
Authors: He Yu Yang , Yuan Quan
Published: October 2013

In this paper, the shaking table test of a 1/6 scale multi-rib composite wall supported on frame was conducted. The test structure has undergone elastic stage and cracking up the whole process of destruction, the dynamic characteristics of the structure in the various stages of change and the dynamic response were recorded. The shaking table test was in two steps, the first step for modal testing, modal test results such as period and damping; the second step was the seismic test to measure the dynamic characteristics of the test structure, acceleration response and displacement reaction to study the bottom frame ribbed composite wall structure under strong earthquake laws of failure and collapse failure criterion.
ABAQUS Dynamic Elasto-Plastic Analysis in Earthquake-Resistant Structure Design
Authors: Zhou Y.Y. , Shen W. , Zhao F.H. , Dai Guo Zhong
Published: October 2013

Since the Wenchuan earthquake in 2008, the earthquake-resistant consideration in structure design is highlighted in the Chinese code. This paper introduces a dynamic elasto-plastic method in structure modeling using ABAQUS finite element analysis. In the first stage, structural models are transferred into ABAQUS INP files. Then the user subroutines are given to describe the elastic and plastic behaviors of both concrete and steel materials. Finally, the models are analyzed in an ABAQUS implicit or explicit analysis. The result can suggest the weakness of the building and provide advisement in reinforcing the structure.
Determination and Analysis of Key Seismic Components of Frame Shear-Wall Structure
Authors: Zeng Gui Xiang
Published: October 2013

Based on the discussion of mechanical characteristics of frame shear-wall structure, the shear-wall is identified as the key component resisting seismic action. In view of the structural design requirements such as reliability and economy, the arrangement, amount and structural details of shear-wall is analyzed and proposed. The research may provide a good reference for engineers to reasonably design the frame shear-wall structure.
A Practical Response Spectrum Method in Considering the Input Angle of Seismic Excitation
Authors: Liu Shi Mei , Xia Ling Tao
Published: October 2013

To the asymmetric-plan structures, the torsion model is obvious, and the influence of input angle of excitation on structural response is sensitive, so a practical response spectrum method for analyzing the behaviors of this kind of structure is studied. Based on the achievements about the multi-components accelerations power spectra matrix, a rational formula, considering the input angle of excitation, is deduced by using stationary random vibration principle. A practical formula is proposed by introducing displacement response spectrum as equally as to considering the non-stationarity of excitation.
Dynamic Nonlinear Analysis of Shanghai Pudong Shangrila Hotel Extension Engineering
Authors: Qi Hu , Li Yun Gui , Lu Xi Lin
Published: October 2013

Shanghai Pudong Shangrila Hotel extension project is a super-high frame-shear wall structure. In this paper, a concrete uniaxial hysteresis constitutive model and a practical elastic plastic damage constitutive model are introduced, both of which are established by the author before, and then both models are developed in ABAQUS via UMAT, and used to simulate Shanghai Pudong Shangrila hotel extension engineering. The numerical model is established in PKPM and then be converted to ABAQUS, in which fiber model is used to simulate the frame elements and sell model is used to simulate shear-walls. Through numerical simulation, we can see that the simulation results and test results are coincided well, which proved that the proposed constitutive models is effective in analyzing large complex structures, and the selected element models are reasonable.
Study on Seismic Performance of Archaized Steel Tower
Authors: Li Xiao Ke , Wang Zhi Hao , Liu Jian , Song Fu Li
Published: October 2013

Combined with the design of Tiantang Site Protection Exhibition Project in Luoyang, China, the seismic performance of an archaized steel tower is studied in this paper. Firstly, a finite element model of whole structure is built accurately with ANSYS software. Then the dynamic behaviors of steel tower are analyzed. The natural vibration frequency and mode shape are obtained. Compared with dynamic test at site, the theoretical values are verified and it is reasonable about adopted loads and boundary conditions in the finite element model. After that, the seismic behaviors of steel tower are calculated and analyzed under seismic intensity 7 degree with methods of spectrum analysis and time-history analysis. The distribution characteristics of displacements and stresses are revealed. The results prove that the seismic performance of the given archaized steel tower can meet the code requirements. It is believed that the results in this paper would give some reference for the design of similar steel tower structures.
Nonlinear Seismic Response Analysis of Canyons in Layered Sites
Authors: Liang Jian Wen , Liu Ming Liang
Published: October 2013

This paper presents nonlinear seismic response analysis of canyons in layered sites. The equivalent linear method is used in the dynamic analysis and Lysmer-Kuhlemeyer transmitting boundary is added at the left and right boundaries of the computation region. It is shown through numerical examples that, soil nonlinearity has significant effect on seismic ground motion around canyons. There are differences between seismic response amplitudes in nonlinear analysis and those in linear analysis, but the differences are smaller for observation points inside canyons. There are shifts between response spectra in nonlinear analysis and those in linear analysis, but the differences are much larger for observation points inside canyons.