bluuebunny/crossref_metadata_2025 huggingface dataset:
A Topology Control Algorithm Based on Pass Loss for Wireless Sensor Network
Authors: Luo Nan Xi , Bao Jie
Published: August 2013

We present PLTC,a distributed topology control algorithm that based on pass-loss for wireless sensor network .In contrast to the algorithm based on RSSI,it can be applied on a heterogeneous network and nodes with different transmitting power.In this paper,we discuss the shortcomings of other parameters used to determine the link quality and present PLTC.We evaluate PLTC by analytic proofs and simulation results.The result shows it has good performance on bounded degree,connectivity and planarity.
Evaluation, Prediction and Control on the Earth's Health
Authors: Ji Xue Bin
Published: August 2013

To study the current state of the Earths health, we divide the Earth into dozens of regions and construct a complex network. Based on the network, we analyze the Earths present health and predict its developing trend. Moreover, the reasonable health level of the Earth can be reached via pinning control. Taking the population for example, we analyze the trend of population in the dynamic network both with control and without control. The results indicate that human behaviors and government policies have great impact on population growth.
Multi-Parameters Measurement Based on STM32 ARM of Dual-Excited Electromagnetic Flow Meter in Partially Filled Pipes
Authors: Suo Ji , Qi Chun Qing , Zhang Hong Bing
Published: August 2013

The dual-excited electromagnetic flowmeter with arc-electrodes in the paper can measures liquid level and flow velocity. A pair of electrodes is set as signal injection electrodes on the pipe bottom. AC signal injected used to determine liquid level. The theoretical analysis and experiment results indicate that it is feasible for partially filled pipes.
A New Design of Three-Legged Robot of Mechanical and Control System
Authors: Cui Hao Tian , Yang Wang , Li Qing Qing , Yu Yue Qing , Ma Li Zheng , Wang Yu Mo
Published: August 2013

A new type of three-legged robot design scheme is proposed and the movement control of it is studied in this paper. Spatial crank rocker mechanism (RSSR) is used to will the motor rotation into a leg swinging in mechanical design. Advanced reduced instruction-set computer machines (ARM) chip, wireless communication module and magnetic encoder are used in controller design. Proportional and differential (PD) closed loop control arithmetic is used to realize the control of the robot. The robot realizes the movement of straight walk, curve walk, turning in situ, jumping and so on. It has a broad application prospect.
Design of State Feedback Controller for Discrete Systems with Time-Delay
Authors: He Shuai Tian , Li Zhi Chang
Published: August 2013

The stability analysis and controller design of discrete linear systems with time-varying delay are addressed. Firstly, the uniformly asymptotical stability criterion with adjustable parameter is derived by Lyapunov-Razumikhin approach. Then, the stabilization approaches for linear systems with time delay by state feedback and observer based-on state feedback are also presented. Sufficient conditions for the existence of state feedback gain and the observer gain are derived through the numerical solution of a set of obtained linear matrix inequalities. Compared with methods in the references, the dynamic performance of systems, such as the overshoot and the convergence rate of the response, can be adjusted by changing the adjustable parameter. Lastly, an illustrative example is given to show the effectiveness of the proposed.
Solution of Inverse Kinematics of a 6R Serial Robot
Authors: Huang Xi Guang , Li Lei Lei , Li Duan Ling
Published: August 2013

A new algorithm for the inverse kinematics of a kind of 6R serial robot was introduced. Firstly, the positions of all the joint points are determined with the help of the basic geometric entities, such as sphere, circle, line, plane and so on. Then, the angles of each joint are computed by the inner product between line and line or plane and plane. The proposed algorithm gives a new geometrically intuitive approach for solving the inverse kinematics of the robot.
The Characteristic Parameter Estimation of Low Temperature Target Weak Signal Based on VanderPol-Duffing System
Authors: Xu Yan Chun , Zhao Dan Feng , Lu Mi
Published: August 2013

The weak signal, which is usually submerged in strong noise, is very difficult to detecte for its amplitude and frequency. The dynamic properties of VanderPol-Duffing are studied in this paper. Such system can go into the chaos under certain parameters. In chaotic state the disturbance of weak periodic signals can make the system dynamic behavior change dramatically. Our research results show that the system is from period doubling state to chaotic state when the amplitude of input signal is changed. And it has a remarkable impact influence on the system dynamic performance when the input frequency is varied. The unknown frequency can be detected through counting the numbers of turning point in phase diagram. The simulation results verified that the presented method is feasible and there are a lot of theory values in the research.
The Design of an Miniature Underwater Robot for Hazardous Environment
Authors: Fang Bin , Chou Wu Sheng , Guo Xiao Qi , Ma Xin
Published: August 2013

An miniature underwater robotic system for hazardous environment has been developed. The system consists of an underwater robot, a robot control station and a cameral control station. The underwater robot is installed two cameras for inspection, one is a camera of radiation resistant with two-freedom PTZ in the front of the robot, and the other is a fixed camera in the back of the robot. A miniature manipulator is equipped under the fore-camera to catch the small parts like bolts and nuts in the pools. The movement of the underwater robot is controlled by the master control station and the cameral control station controls the rotation and focus of the fore-camera. Besides, the underwater robot is equipped with the sensors, as MEMS inertial measurement unit, magnetometers, side scan sonar, water-depth gauges, which are integrated to determine the orientation and location of the robot. Meanwhile the navigation information is displayed in the virtual environment, which is modeled upon the real pools of the nuclear power plant. The underwater robotic system is easy to operate and will be applied to the hazardous environment like nuclear environment in future.
Second-Order IIR Notch Filter Design and Implementation of Digital Signal Processing System
Authors: Wang Chun Mei , Xiao Wei Cai
Published: August 2013

In this paper the AC power 50Hz power interference, we use IIR digital notch filter method for industrial frequency interference filter. From the design of IIR digital filter method proceed with, on the IIR digital notch filter simulation, the algorithm deduced, on the fixed-point DSP programming method and overflow handling problems made elaborate incisively, and in digital audio signal processing system has been applied.
A Pneumatic Miniature Robotic Control System Based on Improved Single Neural Network PID Control
Authors: Li Wen , Li Hong Min
Published: August 2013

At present pneumatic miniature robotic control system usually adopts PID control strategy. The basic PID control strategy has its limitations. To cope with this problem, a lot of methods to optimize this strategy have been researched. In the paper an improved single neural network PID control strategy is put forward. The control strategy is a single neuron adaptive controller with adjusting weighting coefficient. Both simulation and experimental results indicate that this scheme is a feasible control method for the 3-dof pneumatic miniature robotic control system.
Signal Recognition Basing on Optical Fiber Vibration Sensor
Authors: Xu Hai Yan , Zhang Zhuo , Zhang Xue Wu
Published: August 2013

Distributed optical fiber sensor can acquire the information of physical field along time and spatial continuous distribution. It plays an important role in long-distance oil and electricity transmission and security. In this paper, the author introduced the universal steps in triggering pattern recognition, which includes signal characteristics extracting by accurate endpoint detecting, templates establishing by training, and pattern matching. By training the samples acquired in the laboratory, three templates are established. And pattern matching had been done between templates and all the samples. The results show that, 87.5 percent of the samples are matched correctly with the triggering patterns they are belonging to.
Automatic Gauge Control Hydraulic Cylinder State Identification Using Modified Image Based Acoustic Emission Profile
Authors: Chen H. , Lu Y. , Zhao H. , Sun Y. , Wang P. , Huang J.
Published: August 2013

The growing requirements of steel products qualities bring even tricky restrictions to the rolling process. With the fast response, reliable control and low maintenance requirements, the hydraulic automatic gauge control system has been widely applied to screw down the roller to maintain the precise rolling spaces for product quality control. Regarding to non-stopped heavy duties charged to the system, unavoidable faults and disfunctions not only influence the product quality, but also bring underlying safety issues. The hydraulic cylinder is the executing component of the roller screw down and it has the dominant percentage of hydraulic components faults. Working with unexpect loading is one of major impact factor that causes several chain-effects happened to the cylinder, as the classical diagnostic process is lack of cross-validating and time-consuming, the paper proposes the potentials of using acoustic emission to fill the dilemmas. The works include the data acquisition process to record the ultrasound acoustic signals from the hydraulic cylinder during it was loaded with 6 types of conditions, a modified image based acoustic emission approach constructed by using 8 significant waveform features was applied to generate visual effects and transform the cylinder acoustic emission signals under various loadings to a uniform format, the subtle differences among various loadings can be observed based on the pixel and intensity changes of the images. By applying the principal component analysis to project the acoustic emission image profiles onto the 3D plane, a clear trajectory can be observed with normal and overload conditions allocated upon the positive and negative sides of the axis. The result provided not only the potential of using acoustic emission for dynamic state identification of the subtle changes, but also opens up the possibility of preventive measures to the cylinder at risks in the future.
Application of Orthogonal Experimental Design for the Automatic Software Testing
Authors: Wu Hao
Published: August 2013

According to inputting different combination of conditions so as to produce different impacts, software testing designs a large number of test cases. If the implementation of an overall test, due to the limit of the combination of conditions, it is difficult to carry out. In order to generate high quality test cases as early as possible to improve the efficiency of software testing, it is designed a generation tool of the automatic software testing case on orthogonal experimental design. For the test data, the use of that tool design test cases. The practice shows that a small number of test cases are generated, the error detection ability is strong, and it greatly improves the efficiency of software testing.
Design of Mechanical Arm for Laser Weeding Robot
Authors: Ge Zhen Yang , Wu Wang Wang , Yu Ying Jie , Zhang Rui Qing
Published: August 2013

A design of mechanical arm for laser weeding robot is described. The long term objective of the project is the replacement of chemical weeding by laser weeding. The distinguishing feature of this design is the use of a mechanical arm, which is equipped with a laser generator and a control center consisted of a single chip microcomputer and two driver hybrid ICs. The mechanical arm comprises two stepping motors vertically linked together. The robot moves ahead one step, the working area of laser generator is divided into 10×10 grids. Through the inverse operation of mechanical arm, the motor displacement angle of each grid is calculated. Mechanical arm turns to designated position if single chip gets weeds position information. The result of the design is a key executive mechanism of laser weeding. The operation error of mechanical arm is analyzed. The arm can point the laser beam towards the target weeds with small error. After the order of the execution areas is optimized, the length of arm moving path is shorter. Analysis of the running track shows that the sequence of execution area is feasible and reasonable.
Network Video Transmission Quality Assurance Algorithm Based on Congestion Control
Authors: Zhu Hong Gao , Feng Qi
Published: August 2013

Time delay and packet loss rate during the network video transmission are the two important factors in network video transmission quality. The purpose of congestion control is to reduce the bad impact of network video transmission quality caused by time delay and packet loss rate. This paper proposed a network video transmission quality assurance algorithm based on unbalanced multiple descriptions coding scheme. The new algorithm predicts the congestion state of network by means of Markov model based on available bandwidth detection, changes video transmission path on the basis of the prediction. Experiments show that compared with RED (Random Early Detection) algorithm, the algorithm is much more effective to estimate network congestionreduce video packet loss rate and time delay, thus the network video transmission quality can be ensured more effectively.
A Torque Vectoring Control System for Maneuverability Improvement of 4WD EV
Authors: Gan Yi He , Xiong Lu , Feng Yuan , Martinez Felix
Published: August 2013

This paper studies the improvement of the handling performance of 4WD EV driven by in-wheel motors under regular driving conditions. Fundamentally the structure of torque vectoring control (TVC) system for handling control consists of two control layers. The upper layer is a model following controller which makes the vehicle follow the desired yaw rate limited by the side slip angle and lateral acceleration. The torque distribution constitutes the lower layer. Several simulations based on veDYNA/Simulink are conducted to verify the effectiveness of the control system. It is clarified that the control system exhibits satisfactory performance in both open and closed loop maneuvers and the agility of the electric vehicle is improved.
Reliability Analysis of Pressure Meter Electronic System Based on Fault Tree
Authors: Yan J. , Yan Wen Hui , Wang Li Ping
Published: August 2013

Pressure meter is an important testing and storage investment during oilfield hydraulic fracturing. The pressure meter electronic system mainly composed by the microcontroller module, battery module, temperature signal acquisition and processing module, the pressure signal acquisition and processing module and memory module. This paper briefly introduced the principle of pressure meter, and established fault tree based on schematic diagram of pressure meter electronic system and specific cause of failure; Aiming at solving traditional reliability analysis the limitation of long cycle and poor economy, the paper adopt reliability simulation by using MATLAB and combined with the theory of Monte Carlo. Ultimately,getting the reliability curve and life of pressure meter electronic system. The reliability of electronic systems gradually decreases with increasing time and obeyed exponentially distributed law; Electronic system simulation life of 2877.7 hours. In other words, the electronic system can work 2877.7 hours since down to underground of oil well. It has some guidance for engineering practice, as well as provides a measure of reliability analysis for pressure meter electronic system.
Research on Timing Error Effects of UWB System in the Environment of the Internet of Things
Authors: Lu Ying , Hu Wen
Published: August 2013

With Internet of things applies in more and more fields, application of UWB technology is very significant because the network sensory information is needs increasingly. The tolerance of UWB system for timing error interference is much lower than conventional systems because the information is transmitted through a very narrow pulse in UWB system. This paper studies timing effect of UWB system in Internet of things by the means of PPM modulation and time-hopping multi-access, and the experimental results show the impact of different timing error on the performance of system.
Data Aggregation for Failure Tolerance in Wireless Sensor Network
Authors: Wang Na , Wu Yue Ping
Published: August 2013

One of the critical tasks in designing a wireless sensor network is to monitor, detect, and report various useful occurrences of events in the network domain which are determined by the result of data aggregation. Fault tolerance is critical to the efficiency of data aggregation scheme. One important reason is that sensor nodes are neither reliable nor stabile. In this paper, we present an improved k-means data aggregation algorithm considering the proposal of isolated point. Each cluster includes three types of sets: aggregation data, fault data set and abnormal data set. Aggregation data comes from normal sensors in this cluster through the improved K-means aggregation algorithm and abnormal nodes can be detected according to the aggregation result.
Research on Improved Extended Proportional Navigation Guidance
Authors: Feng De Long , Yang Suo Chang , Yao Yun Zhi , Liu Ying Xi
Published: August 2013

This paper proposed an improved method on the basis of the extended proportional guidance law. The method solved the weak observability problem of system sate in guided missile attacking maneuvering target. It is simple in form and easy for engineering implementation. This paper set up relative motion model and the observability theory indexes. The improved propotional guidance law is simulated using the MATLAB language. The simulation results show that the method is reasonable, effective and improving the observability.
Research on Automatic Magnetic Deviation Compensation of Electronic Compass for Quadrotor
Authors: Xiao Wen Jian , Lu Ping
Published: August 2013

In magnetic heading measurement of quadrotor, it is necessary to compensate the magnetic deviation of the electronic magnetic compass. For the flight characteristics of quadrotor, a method using sampling data when the aircraft is in the air to achieve automatic compensation of the deviation has been proposed. Using elliptical hypothesis method one can only compensate deviation for quadrotor flying in horizontal plane by collecting the magnetic sensor data in different directions. When the quadrotor flying in any attitudes, using ellipsoid hypothesis method can obtain parameters used by magnetic deviation compensation. Using these parameters, the pitch and roll angles of quadrotor, the magnetic deviation could be compensated. Experimental results show that this method works well and has a good real time performance. The measurement error of heading angle could be less than 1 °.
The Safety Assessment of Bored Pile Retaining Wall Based on Back Analysis for Bending Moment
Authors: Liu Tao , Chen Yun Bin
Published: August 2013

Dynamic safety assessment of internal force of retaining wall is of great significance to ensure the safety construction of deep foundation pile, and the key is to get the actual bending moment. The curvature is acquired by curve fitting of retaining wall reformation with the least squared method, and the actual bending moment can be obtained by multiplying the curvature and retaining wall bending stiffness. This method overcomes the difficult that the actual bending moment cannot be directly measured, at the same time, the cost savings would be of great advantage. As the monitoring item of foundation pile which must be implemented, retaining wall deformation has sufficient data, which provide a solid foundation for the engineering application of back analysis of bending moment. This studied the safety assessment of bored pile retaining wall based on back analysis for bending moment and obtained some beneficial conclusions.
Analysis of the Primary Consolidation Settlement Considering of the Settlement Load
Authors: Yu Jiong Qi , Wu Xiong Wei
Published: August 2013

Aiming to improve the calculation result of the total settlement of soft ground of seawall engineering in design, one seawall engineering case is enumerated, and the changes in the thickness of compressible stratum and the primary consolidation settlement are studied by considering the settlement as filling load. The results indicate that the thickness of compressible stratum is increased and the growth of the primary consolidation settlement is about 30% in contrast with the primary consolidation settlement only considering the design load. At last, this paper suggests that a designer should weaken the weight of settlement correction coefficient instead of strengthening the settlement as filling load in future design.
Subgrade Slope Stability Analysis under the Condition of Rainfall Infiltration
Authors: Guo Guang Jun , Liu Guang Hua , Sui Jun , Wu Jian Qing
Published: August 2013

On basis of limit equilibrium analysis methods for theory of unsaturated soil mechanics, silt subgrade slope stability under the condition of rainfall infiltration is analyzed and the factors affecting the stability of subgrade slope are presented in this article, which provides theoretical basis and technical support for future subgrade construction.
The Zonal Disintegration Law within Coal in Front of Working Face in Deep Coal Mine
Authors: Chen Qing Feng , Chen Zhong Hui , Ma Ning , Zhang Wei , Li Hui
Published: August 2013

The mining coal in the front of long wall face consists of elastic zone, plastic zone and fracture zone. Based on the research of zonaldisintegration of surrounding rock mass in deep tunnel, the zonal disintegration phenomenon of deep coal mine was analyzed by using the theoretical analysis method. On the basis of the Griffith theory, the internal and external boundary formulas of fracture zone and the mechanical criteria of zonal disintegration were obtained. The research shows that the essence of zonal disintegration is the tensile failure and brittle tension crack failure under the abutment pressure, the main influence factors of the width variation of fracture zone are original rock stress and un-axial tensile strength of coal.
Study on the Small-Strain Behaviors of Unsaturated Soils
Authors: Wang Jin Xing , Liang Wei Min , Yu Yong Qiang
Published: August 2013

Non-linear stress-strain characteristics and strain dependency of stiffness of saturated soils at small strain level have been reported by many researchers. However, the non-linear stiffness of unsaturated soils is not fully studied. The aim of this study is to clarify main factors affecting the non-linear stiffness of unsaturated soil at small strain range for a precise prediction of various ground deformations. Experiments were conducted with both sand and cohesive soil, by using a triaxial apparatus developed for small strain measurement. As the important factors for mechanical behaviour of unsaturated soils under small strain range, the effects of suction and mean net stress, which introduce the decrease of void ratio and degree of saturation, were discussed in the study.
Forecasting of Landslide Displacement Based on Exponential Smoothing and Nonlinear Regression Analysis
Authors: Zhang Wei Zhong , Li Yao Ji , Li Xiao Shuang , Kang Qin Rong
Published: August 2013

The landslide forecasting study is one of the hot problems in landslide research. Based on the actual observation data, the exponential smoothing and nonlinear regression analysis are integrated. According to the criteria of displacement and displacement velocity, the dynamic track prediction about the slippage time of landslide is introduced. In light of the practical landslide conditions, a model was established for the special displacement of some monitoring points£¬ and the prediction based on this model was obtained with high accuracy. Therefore, the method can be used in practical engineering.
The Analysis about Seepage of the Bank Slope under the Cycle Rising and Drawdown of Reservoir Water Level
Authors: Liu Xiao Wen , Wan Wen , Shen Xi Zhong
Published: August 2013

Bank slope seepage field is analyzed by saturated-unsaturated seepage theory under the three times cycle conditions of water level rising and drawdown . The pore water pressure distribution laws of the water level rising period, the stabilization period, the period of decline and decline stable period for every cycle are researched. The result shows soil near slope region is saturated easily after many rounds of water level rising and drawdown, and saturation region gradually increases. Soil phreatic line near slope falls fastly in the drawdown period, away from the slope, phreatic line declines slowly.
3D Fracture Network and Block Analysis of the South End-Slope of Antaibao Coal Mine
Authors: Ming Ma , Li Hong Jie , Lei He
Published: August 2013

Based on actual measurement of fractures in south end-slope of Antaibao Coal Mine which adopted open-pit and underground mining, the fractures were grouped by directions, and for each group, distribution functions of direction, length and other geometric parameters and density on the observation window were calculated respectively. The statistic results showed that the fracture orientation followed Fisher distribution and the trace length followed lognormal distribution. According to the fractures number, the mean traces length and standard deviation, as well as one-dimensional density of each group, 3D fracture network was simulated with Monte-Carlo method. Then the block theoretical model was built according to the fracture model, and the block distribution of the south end-slope was analyzed and forecast.
Forecasting Major Geological Hazards about Construction Projects of Mengshan Lead-Zinc Mining
Authors: Shi Guo Dong , Wang Juan Juan , Yang Chun
Published: August 2013

On the basis of the analysis of the Mengshan lead-zinc minings geological hazards in Wuzhou City, Guangxi province, the paper forecasts the major types of geological hazards which can be triggered are collapse, landslide as well as the goaf ground subsidence, and studies the causes and the occurrence possibility of them by the improved principle of stereographic projection and calculation method of goaf ground subsidence, which can offer a valuable reference to similar mine construction project in the future prevention of geological hazards.
The Fractal Characteristic Analysis of Coal Pore Structure Based on the Mercury Intrusion Porosimetry
Authors: Hao Nai , Wang Yong Liang , Mao Ling Tao , Liu Qing
Published: August 2013

The pore structure of coal rock atYangquan Xinjing mine in Shanxi Province is analyzed with mercury intrusion porosimetry to obtain the specific pore volume data and calculate the fractal dimension of coal pore surface. The pores are divided into macropore, mesopore and micropore according to radius size considering the calculated fractal dimension. The distribution characteristics of pore radius size, specific surface area and specific pore volume of different types are effectively analyzed. The research results show that mesopore surface has significantly fractal characteristics, which features could be discussed quantitatively. The proposed method in this paper has reference significance for studying the sorption and desorption properties, the diffussion and permeation of coalbed methane.
Statistical Analysis the Distribution of Landslide Triggered by m 8.0 Wenchuan, China Earthquake of May 12, 2008
Authors: Tian Shu Jun , Kong Ji Ming
Published: August 2013

Abundant landslides were triggered by Wenchuan earthquake. The paper mapped 4722 earthquake-induced landslides and used Geographic Information System to finish the statistical data about the occurrence of landslides correlating with environmental factors including distance from middle faults, lithology, altitude, river, and slope steepness. Because the seismic energy released along the middle faults and the attenuation of energy was obvious in minor axis, the zonal distribution of landslides was consistent with strike of middle faults and about 64.42% of landslides occurred within 20 km from middle faults of Longmenshan. As the middle faults and front faults both belonged to thrust faults, the impact of earthquake in hanging wall was higher than that in footwall. Therefore, the density of landslide in hanging wall of middle faults was obviously higher than that in footwall. As the release of seismic energy was restricted by landform and river, landslides were concentrative and consistent with the spatial distribution of rivers in the mountainous terrain. The scale effect of seismic acceleration was so intense in top of mountain with high difference in elevation along river that the origin of most landslides were in upside of slope. About 99.43% of landslides distributed in area where the seismic intensity was more than VII.
Design of Shallow Depth Tunnel with Asymmetric Twin Arches and its Construction Procedure in Poor Rock Mass
Authors: Zhou Xiao Jun , Wang Xiao Feng
Published: August 2013

An asymmetric twin arched tunnel is designed to meet the line development of triple track railway in accordance with ground geological condition and topography in this paper. A partition wall is adopted to support the double arches of the tunnel, and the pilot drift and bench cut method is utilized to preserve the safe excavation of the double arch tunnel in poor rock mass in the paper. The design technique and construction method may guide the driving of such tunnels under similar condition.
Simplified Calculation Method of Normal Water Depth on II Type Horseshoe Tunnel with Flat-Bottom
Authors: Wen Hui , Li Feng Ling
Published: August 2013

Abstract: II type horseshoe with flat–bottom evolved from standard II type horseshoe cross-section. It is composed of a flat-bottom and three arc sections. It is commonly applied in the field of hydroelectric engineering. The normal water depth computation equation for II type horseshoe cross-section with flat–bottom tunnel is a transcendental equation and no analytic solution. In this paper, based on the mathematics transformation for the basis equation and the relationship analysis between the dimensionless normal water depth and the relative parameters, a simplified calculation formula is established for the calculation of normal water depth for II type horseshoe cross-section with flat–bottom tunnel according to the fitting principle. This method overcomes the shortage of other iterative trial calculating methods, such as complex calculation step, depend on the special chart and curve, and existed serious error. The formula is simply and the maximum error is less than 0.23% under the general engineering design range (ratio of normal water depth and arch radius is between 0.05 - 1.45). it can be used on the engineering designing practice and the edit of the handbook of hydraulic structure design.
Study on Selection of Segment Lining Structure for Large Profile Underwater Shield Tunnel
Authors: Guo Rui , He Chuan
Published: August 2013

Based on Nanjing Yangtze River Tunnel project, the selection of segment lining of large profile underwater shield tunnel was analyzed. Considering from structure force, construction and economic, the comparison and selection for assembling modes, joint form, blocking modes, thickness and width of segment lining was carried out, The better segment lining structure was obtained. The study results can offer references for the design of segment lining of similar large profile underwater shield tunnel.
Research on High-Efficiency Rock Fragmentation of TBM Cutter-Head
Authors: Feng Huan Huan , Chen Kui , Wang Zhu Feng
Published: August 2013

Rock breaking mechanism and coupling effect rule between cutter tool and surrounding rock were researched, in order to resolve the shield construction problem of shield cutter tool breaking rock. The optimal broken rock cutter spacing of some common rocks was put forward, and the broken rock mechanism of multi-tool is perfected. Considering the impact of various factors,this paper obtains a new calculation method of compound shield total thrust force and cutter-head torque with mathematical and mechanical methods. The research results can be used for design of thrust force and torque, tool selection and arrange.
Study and Application of Displacement Back Analysis Based on CACA-SVM
Authors: Xu Fei , Li Bin , Wang Ke
Published: August 2013

An new intelligent displacement back analysis, named as CACA-SVM, was proposed based on support vector machine (SVM) and Continuous Ant Colony Algorithm (CACA). On the one hand, CACA-SVM used SVM to build the nonlinear mapping relationship between them. On the other hand, CACA-SVM used the global optimization performance of CACA to search the optimal rock mechanics parameters in the global space. The nonlinear mapping relationship built by SVM can fit and forecast the measuring point displacements under different parameters with high accuracy, avoiding the complex numerical calculation. CACA can prevent object function from trapping in local optimum and improve precision of back analysis. Case study shows that the forecasting trend was in good agreement with the measured trend, which indicated that the model was suitable for solving the geotechnical engineering problem of nonlinearity and uncertainty and could well be applied to displacement back analysis.
Field Test Study on Cutting Obstacle Piles Directly by Shield Cutters
Authors: Wang Fei , Yuan Da Jun , Cai Rong , Mu Yong Jiang , Wang Meng Shu
Published: August 2013

Shield cutting obstacle pile directly has significant economic and social benefits compared to traditional methods, however, the corresponding cutting technology is far from mature currently in the international. Based on the construction need of cutting 14 bridge piles with the diameter of 1.0~1.2 meters by Suzhou subway shield, the preliminary scheme of cutter configuration was studied and proposed first, and then the worlds first field test of shield cutting reinforced concrete piles was carried out, the effect and rule of shield cutters cutting piles were analyzed, and the cutter configuration scheme was verified and optimized. The test results indicate that the shell cutter is fit for cutting reinforced concrete pile, its cutting effect on rebar and concrete is shear cutting; In order to make rebar shorter, we should make the rebar be cut off instead of pulled off as possible as we can. The main damage form of shell cutter is alloy cracked. Cutting side pile produces more damage on shell cutter than cutting central pile. The shell cutter configuration scheme should not only satisfy the whole cutting ability and covering the entire cutting plane, but also to be favorable to fix rebar by surrounding concrete.
Study on the Human Behavior in Metro Fire
Authors: Zhao Guo Min
Published: August 2013

With the rapid development of city subway, subway disaster problems aroused people's attention. Subway fire especially priority among priorities in subway disaster. This research mainly rely on the way of questionnaire survey, conducted a statistical study on metro fire evacuation behavior. The author has carried on questionnaire investigation to the passengers of some subway station in Tianjin Metro Line 1. The author sent out 116 questionnaires, received effective questionnaires 100 copies. The questionnaire content mainly includes the basic personal information, the surrounding environment and the passenger behavior in fire condition. The author analyzes the first behavior survey of different sex, different age, different education, different frequency and different subway fire experience reaction. Management departments according to the behavioral responses of passengers improve and optimize the subway facilities and fire evacuation passage.
Breakage Probability Calculation of Shield Tunnel under the Effect of Foundation Pit Excavation
Authors: Guan Yong Ping , Zhao Wen , Xie Xin , Li Shen Gang , Wang Guo Feng
Published: August 2013

The excavation of foundation pit will change the initial stress state in surrounding soils, which induce the superimposed stress and uneven settlement to the adjacent existing tunnels. Based on the pit excavation engineering in Shenyang, which sits atop the existing tunnels, the risk factors and failure type of shield segment lining were studied through risk analysis theory. According to the uncertainty and spatial variability of soil parameters, the risk accident of existing tunnel was calculated by means of stochastic finite element which is combined Monte Carlo simulation with FEM. The risk of existing tunnel during the pit excavation stage was evaluated respectively under multi-failure patterns. The framework is used to estimate and minimize risks at pit excavation engineering in Shenyang.
The Influence of Engineering Factors to Groundwater Recovery in Mountain Tunnel
Authors: Liu Zhi Chun
Published: August 2013

Groundwater flow into mountain tunnel can lead to drawdown and groundwater loss in tunnel construction and operation stages under drainage and limited drainage principle conditions. The author defines groundwater recovery degree of drawdown and volume change, and simulate drawdown and groundwater recovery process adopting nonhomogeneous and anisotropic equivalent tunnel flow model, and study influencing effect of various factors to groundwater recovery by numerical method. The results show that the essential condition of groundwater recovery in tunnel is that groundwater recharge is greater than groundwater inflow volume, which can be controlled by efficient waterproof and drainage measures. The efficient measures include curtain grouting, radial grouting and high impermeability performance of shotcrete.
Analysis and Evaluation on Stability of the Steep Coal Seam Gob
Authors: Zhang Zhi Pei , Liu Xiao Fei , Meng Ting
Published: August 2013

Constructing on the gob, especially the steep coal seam gob, will put the new buildings in jeopardy, because the gob and its overlying strata is already distorted and damaged with time passing away[. In this paper, it takes the steep coal seam (75°) gob area in Xin Jiang province as the research object, and applies the theory of mining subsidence to analyze and evaluate the stability of the field, combining with the actual investigation. The result demonstrates that the mined-out area is in a state of instability and requires reinforcement[2].
Analysis on Ground Settlement Induced by Shallow Buried Cross Channel of CRD Method under Artificial Filling
Authors: Li Jin Kui , Li Jing Jing , Du Liu Jie
Published: August 2013

The shallow underground tunnel is near to the ground; its many construction procedures are complicated, supporting and excavation are intertwined. The ground surface deformation is complex during construction. Through the analysis of the cross passage surface settlement data of Dalian metro Line 1High-tech zone Street station, we found that the ground surface caused by artificial filling integrally sinks during excavation, the shape of its sinking is like a flat funnel, the characteristics of settling tank are obvious. The influence of faces constructing is obvious on surface settlement, and the transverse influence range is about 30m; the longitudinal influence range is about 15m. The results of the paper show that the place of monitoring points should be held at 15m ahead from the tunnel face, effectivemonitoring period is 70d. The monitoring results are enough and safe for the stability requirement of the surrounding rock.
Safety Evaluation Model for Traffic Operation Environment of Freeway Tunnel
Authors: Guo Yan Yong , Wu Yao , Jin Yuan , Qi Jian Feng
Published: August 2013

This study developed a safety evaluation model for traffic operation environment of freeway tunnel based on the grey entropy weight clustering. Firstly, a safety evaluation system was proposed including four aspects related road conditions, traffic operating conditions, environmental conditions and climate condition. Secondly, whitenization weight function was defined and weights of indexes were determined by entropy theory. Thirdly, the grey entropy clustering coefficient was calculated, and the safety level for traffic operation environment of freeway tunnels was evaluated. Finally, a case study of seven tunnels of XI-HAN freeway was conducted to verify the feasibility and effectiveness of the model.
Study on the Tests of Soil-Water Characteristic Curves of Unsaturated Soil
Authors: Zheng Xian Chun , Zhao Fang , Sun Si Zhong
Published: August 2013

Soil-water characteristic curve is used to describe the matrix suction and water content of the curve of the relationship between volume, according to the soil-water characteristic curve can be deduced the unsaturated soil shear strength, permeability coefficient, etc., this paper gives the different initial water content and different types of soil, soil-water characteristic curve for practical engineering foundation reinforcement to provide reference.
Deformation Monitoring and Data Analysis for Metro Construction with Mining Method in Dalian
Authors: Bai Guang Bin , Zhao Jie , Liu Li Sheng
Published: August 2013

Based on a subway tunnel construction, the construction method was introduced. The ground subsidence, crown settlement and convergence displacement caused by the cut tunnel are monitored during the tunneling construction and the results of monitoring data for them are analyzed. This technology wells to guide the tunnel-entering construction effectively and avoid the tunnel-entering construction process prone to landslides, thus ensuring the safety of the tunnel construction and will guiding the future construction.
Static and Dynamic Analysis for Ovaling Deformation of Circular Tunnels under No-Slip Conditions
Authors: Lu Qing Rui , Jiang Hai Ying , Andrea Perino , Xie Dan
Published: August 2013

Many underground structures have witnessed great damage in recent earthquakes. Thus underground structures in earthquake prone zones should be designed to withstand both static overburden loads and earthquake loads. In this paper, different closed form solutions for the analysis of the tunnel response, are considered as developed on the basis of the theory that the stress increment due to seismic loading can be assessed through a correct estimate of free-field deformation, while the internal forces of tunnel linings subjected to overburden loads can also be estimated through an assumption of far-field stress using the developed solutions. Numerical studies have been performed to validate the available analytical solutions.
Research on Construction Technology of Shallow-Buried and Long-Span Railway Tunnel in Soft Rock
Authors: Huang Nan Qing
Published: August 2013

Based on the construction of the New Yangshi Tunnel, a section of the electrified speed-up reconstruction project in Zhe-Gan Railway, the author discusses and studies the construction technology employing annular excavation with core soil reserved method, together with the use of H175 steel frame as initial support in the shallow-buried and long-span railway tunnel in soft rock. Through the technical and economic comparison, it shows that the present method is faster, with the construction progress of 50m per month in average, and is more economical in construction than Center Diaphragm (CD) method with an investment of 4,000,000 Yuan having been saved.
Influence of Tunnel Excavation on Adjacent Rigid-Flexible Pile Bearing Horizontal Loads
Authors: Ma Shao Kun , Huang Yan Zhen , Zhou Xiao Bing , Chen Xin , He Jian Xing
Published: August 2013

In order to investigate the influence of tunnel excavation on adjacent rigid-flexible pile bearing horizontal load，many three-dimensional numerical analysis were conducted by altering the pile-soil stiffness resulted from the change of elastic modulus, radius, and length of pile. Many useful conclusions can be drawn. The longitudinal shear force and transverse bending moment of pile increase with the increment of longitudinal horizontal loads and pile-soil stiffness ratio for the pile of constant length. Therefore, different measures must be executed to protect adjacent piles with different stiffness during tunneling. This study can provide some references for the design and construction of tunnel.
Properties of Frozen Soils for Cross Passage Construction in Line 1 and 2 of Wuxi Metro
Authors: Hu Xiang Dong , Han Yan Guang
Published: August 2013

Artificial ground freezing method (AGF) was applied in cross passage constructing of line 1 and 2 of Wuxi Metro. Mechanical properties of frozen soils such as uniaxial compressive strength, modulus of elasticity, Poissons Ratio, frost heave rate and freezing point are prerequisite for design and construction of AGF. In order to obtain the parameters mentioned, laboratory tests were conducted. One was the basic geotechnical test. Another was the frozen soil test.
Research on Effects of Underground Roadway Arrangements for Surround Rock Bearing Capacity
Authors: Gao Quan Chen , Li Jing Pei , Meng Meng , Wang Xiao Yan
Published: August 2013

Through the mould contrasting experiments the carrying capacities and deformation effects of surround rock with different underground roadway arrangements are studied in this paper. On the basis of experiment measuring results the bearing capacities and strains of surround rock moulds in different stratum roadways and arrangement positions are obtained. It is shown that underground roadway positions in weak rock stratum can bring about more decrease in surround rock bearing capacities and the positions below weak stratum can have high bearing capacity under the high ground pressure actions. The roadway horizontal space enlarging one times may increase more 25% bearing capacities of surround rock for rock or weak stratum roadway. The dislocation arrangements of roof roadway with below weak stratum roadway can improve about 41.5% bearing effects and have a little deformation of surround rock. The research conclusions are important significance of conducting for reasonable designing underground roadway engineering.
Study on High Prestressed Anchor Beam Supporting Optimization Technology in Deep Roadway
Authors: Li Hui , Liu Wen Jiang , Qiao Wei Guo
Published: August 2013

Coal mine has stepped into deep mining period in China, in which the ground pressure is great, the stability of the surrounding rock is poor and roadway is seriously destroyed. 3302 trick roadway of Zhaolou coal mine is the kilometers depth roadway, under the condition of original supporting, the roof settling amount and the surrounding rock deformation were large, which made bad effect on safety production. The surrounding rock failure region was monitored by borehole televiewer and ground penetrating radar, and the loosening failure law was analyzed. The scheme of high prestressed anchor beam was proposed according to the detection results, the crack distribution of surrounding rock and the stress of blots and anchors of original scheme and optimized scheme were analyzed by UDEC. The results of numerical simulation and field monitoring showed that increasing prestress of blot and anchors was better for the control of roof separation in anchorage zone and maintaining the integrity of roof, and high prestressed anchor beam can effectively improve the effect of surrounding rock control in roadways.