bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Backwashing on the Characteristics of Sand Filtration Effluents: Organic and Microbial Analyses
Authors: Lin Jian Li , Kao Chih Ming , Chen Jen Jeng , Liao Shao Wei , Chung Chung Yi , Lai Wen Liang
Published: August 2013

In this study, the head loss, turbidity, particle size, and zeta potential were monitored from the effluent of the sand filtration system after backwashing located in Cheng-Ching Lake (CCL) Water Treatment Plant. Moreover, the non-purgeable dissolved organic matter (NPDOC) and excitation emission fluorescent matrix (EEFM) were measured for the collected water samples with or without the pretreatment process. Results indicate that the turbidity of the influent dropped to 0.06 NTU and remained stable after flowing through the sand filter during the 4-hr operation period. However, a continuous increase of the head loss and sand particle size for the sand filter was observed. This phenomenon was opposite with the absolute value of zeta potential. The water samples were collected from the effluent of the sand filter and were treated by a 0.2 μm membrane filter. Thus, higher NPDOC values of sample without pretreatment were observed in comparison with sample with treatment. Results indicate that the sand filter was able to remove NPDOC, and bacteria might proliferate among the sand filter in rapid filtration. Results from the EEFM analyses show that effluents without membrane filtration pretreatment contained a higher percentage of aromatic protein. Compared to the water samples without pretreatment, more humic-like substance was found in the effluent. This reveals that microbial products or bacteria were detached from the fillers after the backwashing process.
Soil Water Infiltration and its Affecting Factors
Authors: Zhang Zhong Yuan , Sa Teng Teng , Tie Xiao Qiang , Lan Hong , Zhang Wei Hua
Published: August 2013

Through comparing and analyzing domestic and foreign research on soil infiltration in recent years, this article summarizes the research progress on soil infiltration, especially the innovation in theory, method and progress in practical use and gives the advantages and disadvantages among various methods. It can provide reference for the researchers engaged in the study of soil infiltration and efficient soil water utilization.
Design of Terminal Controller of VAV Air-Conditioning System Based on BAS3000 DDC
Authors: Yu Ying , Jia Yuan
Published: August 2013

The terminal device (VAVBOX) is the key part in variable air volume (VAV) air conditioning system, by which we can adjust air output, compensate indoor load change, keep room temperature to be constant. The control effect of VAV system depends largely on the performance of terminal device and the coordination between terminal device and the whole system. In this paper, BAS - 3520 DDC produced by Advantech corporation is used to design VAV air conditioning pressure independent terminal controller. Experiments show that the terminal controller based on DDC can well satisfy the system control requirement, the transition time and overshoot of the indoor temperature achieve good improvement. At the same time , with Webaccess introduced, VAV BOX operation condition can be monitored by host computer, what makes the daily management of the VAV BOX more intelligent.
Application of Solar Thermal Utilization in New Rural Construction in Lanzhou Region
Authors: Hou Cai Qin , Hou Hui , Li Chun E
Published: August 2013

Solar energy is clean and reproducible energy,it has an important advantage when we use solar energy in heating,supplying hot water and drying in residential buildings.Practical experience confirms that appropriate design of these systems can achieve good results to use solar energy if they compared with conventional system.This paper aims to investigate the good use for solar energy in new rural construction of Lanzhou, we integrate traditional passive solar house, solar heating, solar drying into a new classified system ,design the versatile system for lowtemperature radiant floor heating,supplying hot water and crops drying.Meanwhile, control method and handling precautions are improved.Through further analysis on economic efficiency comparison with solar floor heating and conventional heat source with new rural residential integrated energy price method,analysis on energy-saving and environmental benefit.At last we come to the conclusion the system is worth popularizing in new rural construction.
Optimization Settings Application Analysis of Peak-Shaving Heat Source in Large Scale Flow Loop Heating Network
Authors: Guo Hai Jiao , Sun Chun Hua , Qi Cheng Ying , Jin Feng Yun , Zhang Liang
Published: August 2013

Set up the optimized target function by theoretical analysis of peak-shaving heat source optimization settings, determined optimal locations of peak-shaving heat source and capacity matching relation by comparison analysis. Concluded and analyzed optimal locations and heat capacity matching rule of each heat source when multiple heat sources worked jointly. Results and conclusions provide a valuable reference to the formation on combined economic operation pattern in large scale loop network using multiple heat sources.
Experimental Research on the Parameter Optimization of a Radiant Floor Heating System with Reflective Modules
Authors: Yu Jin , Feng Jiang Fa
Published: August 2013

The combination of reflecting cavity and cover layer makes it possible for a reflective radiant floor heating system to be characterized by uniform temperature field and low energy consumption. In this paper, the temperature distribution of a reflecting radiant floor heating system in an experimental chamber was tested under different heating conditions by use of copper constantan thermocouple; the temperature distribution of indoor workspace and floor surface was researched when water temperature was at 30°C, 40°C and 50°C and water flow at 0.24m3/h, 0.34m3/h and 0.44m3/h respectively; the temperature distribution on the surface of floors with three different layout patterns was compared. The results prove that a floor equipped with cover layer has a uniform temperature distribution on its surface. When water temperature is at 40°C, and water flow at 0.34m3/h, indoor workspace temperature remains at 20°C, and floor temperature can be controlled between 23°C and 26°C, satisfying peoples daily need for thermal comfort.
Analysis on the Indoor Temperature in Households of Heating Metering with Work Mode
Authors: Chen Cai Ling , Sun Chun Hua , Xia Guo Qiang , Yang Hua , Qi Cheng Ying
Published: August 2013

Based on the theory of the room heat balance ,this paper discussed the 24 hours indoor temperature with work mode ,and concluded that indoor temperature changed in three stages:steady period, cooling period and warming period .By testing the actual indoor temperature of different heating ways with work mode and comparing the cooling process of theory results with field measurements after the temperature control valve closed ,concluded that the theory results and field measurements were basically the same and if the temperature control valve was closed less than ten hours in the daytime, the largest reduction of indoor temperature were about 2 ~ 3 °C, and it wont reduce people's comfort with work mode when indoor or outdoor temperature was high.
Elastic Flexural-Torsional Buckling of Beam-Column with Equal-Leg Angle Cross-Section
Authors: Qin Jian , Xia Yong Jun , Zhang Jin Miao , Hu Chun Hua
Published: August 2013

The flexural-torsional buckling of equal-leg angle member under compression is analyzed and calculated. Based on General bending theory and the section properties of angle, the governing equations of the spatial buckling are presented and the formula of Wagner effect coefficient is deduced. The method can also be used for beam-columns with any type section, and the computational efficiency is much higher than numerical methods. The critical buckling loads of equal-leg angle members with different sizes are calculated and the column curves of critical load and slenderness ratio are plotted which will guide efficiently the actual engineering design.
A Simulative Method on Gas Seepage in Coal Seam around Borehole
Authors: Cheng Guo Qiang , Wang Yi
Published: August 2013

Based on the analogy between equations of gas seepage in coal seam and that of thermal conduction, a simulative method on gas seepage in coal seam was proposed through that thermal conduction interpreted as gas seepage. The laws of gas emission from borehole in homogeneous and heterogeneous coal seam were analyzed using this method. It indicates that the simulative results of the gas emission from borehole in homogeneous coal seam were satisfied with the corresponding theoretical results during the early stage of gas seepage, while a tolerance between the numerical results and the theoretical ones was appeared in the later period. This is due to the simplification as solving the theoretical equations. The results of heterogeneous coal seam show that curves of gas emission rate conform to the actual situation. The numerical simulation method on the law of gas emission from borehole in coal seam is feasible.
Solution for a Class of Quasilinear Elliptic Equation with p-Laplacian
Authors: Xiu Zong Hu
Published: August 2013

In this paper, a class of elliptic equation with convex-concave nonlinear term is considered. By the variational methods, we give a sufficient condition which insures that the problem considered in the present paper has at a nontrivial nonnegative solution.
The Calculation and Judgment of Critical Connections of the Outer-Shell Connections
Authors: Cao Xin Li , Tao Zhong , Cai Hao Ming
Published: August 2013

Under seismic action, it is easy for the traditional steel nodes to produce a greater degree of brittle failure. The assembly of steel outer annual node after its manufacture in the factory reduces the shear deformation of the structure, and improves the rigidity of the node. The destruction of the structure occurs mainly in some critical parts. By making a calculation of critical connections in this article, we can make the structure more secure.
Correct Wavelet-based Multilevel Discrete-Continual Methods for Local Solution of Boundary Problems of Structural Analysis
Authors: Akimov Pavel A. , Mozgaleva Marina L.
Published: August 2013

The distinctive paper is devoted to correct wavelet-based multilevel discrete-continual methods for local solution of boundary problems of structural analysis. Initial discrete-continual operational formulation of the considering problem and corresponding operational formulation with the use of wavelet basis are presented. Due to special algorithms of averaging within multigrid approach, reduction of the problem is provided. Resultant multipoint boundary problem of structural mechanics for system of ordinary differential equations with piecewise-constant coefficients is given.
Thermal Stress Analysis Based on Equivalent Age of Heterogeneous Mass Concrete
Authors: Su Pei Fang , Lu Xing Li
Published: August 2013

In order to analysis thermal stress of mass concrete accurately, material properties of mass concrete are studied by numerical simulation method, and the equivalent age is introduced to describe the mechanical properties of concrete. The calculation models of concrete mechanical parameters are summarized, and then the calculation procedures are established on the basis of equivalent age. In this way, the temperature and temperature history are considered in these models. Meanwhile, the governing equation and computer program of the thermal stress based on the equivalent age are developed. The comparison of the numerical example using proposed method and conventional FEM method shows that the proposed method performs more adaptable and accurate.
Analysis on Displacement and Stress of the Solar Collector Brackets under Wind Load
Authors: Fang Zhi Hua , Zhang Wei Na , Yuan Yong Qing
Published: August 2013

The finite element model of the combination bracket about solar collector was built and modal characteristics of the structure were analyzed. Wind speed time series was simulated in a given wind speed of the wind power spectrum by AR mode of linear filtering and fluctuating wind load time samples were got in each node on the windward side. The curve of load time series was took as the power input, and the wind-induced response of structures was calculated under random wind loads by the transient analysis. The results show that the large displacements appears on the edge of Collector components along horizontal and vertical direction in the case of fluctuating wind and the greater stress occurs in the joint of the cantilevered brackets connect and the upper end of the torque box, so it should be noted in the design of brackets of solar collector.
Methods & Prospects of Research on Flexible Multi-Body Dynamics
Authors: Yao Lin Xiao , Yang Lian , Shangguan Lin Jian
Published: August 2013

This paper summarized the research method of flexible multi-body system dynamics. Three stages of flexible multi-body system model are reviewed. The paper is especially summary on modeling method of flexible multi-body system, flexible multi-body dynamical equation numerical calculation and flexible multi-body system vibration control and so on. And the paper is looked forward to further study.
Comparison of Analytical Solutions with Finite Element Solutions for Ultimate Bearing Capacity of Strip Footings
Authors: Dai Zi Hang , Xu Xiang
Published: August 2013

The finite element method is used to compute the ultimate bearing capacity of a fictitious strip footing resting on the surface of c-φ weightless soils and a real strip footing buried in the c-φ soils with weight. In order to compare the numerical solutions with analytical solutions, the mainly existing analytical methods are briefly introduced and analyzed. To ensure the precision, most of analytical solutions are obtained by the corresponding formulas rather than table look-up. The first example shows that for c-φ weightless soil, the ABAQUS finite element solution is almost identical to the Prandtls closed solutions. Up to date, though no closed analytical solution is obtained for strip footings buried in c-φ soils with weight, the numerical approximate solutions obtained by the finite element method should be the closest to the real solutions. Apparently, the slip surface disclosed by the finite element method looks like Meyerhofs slip surface, but there are still some differences between the two. For example, the former having an upwarping curve may be another log spiral line, which begins from the water level of footing base to ground surface rather than a straight line like the latter. And the latter is more contractive than the former. Just because these reasons, Meyerhofs ultimate bearing capacity is lower than that of the numerical solution. Comparison between analytical and numerical solutions indicates that they have relatively large gaps. Therefore, finite element method can be a feasible and reliable method for computations of ultimate bearing capacity of practical strip footings.
Application of the R-Function Theory and Variational Method for Torsion Problem with Complicated Cross-Section
Authors: Li Shan Qing , Yuan Hong
Published: August 2013

The R-function theory and variational method are employed to solve the torsion problem of the bar with a complicated cross-section. When the variational method is used to solve the elastic torsion problem alone, the stress function can be set to meet the boundary condition, only with the simple cross-section such as the rectangle and ellipse. For the complicated cross-section, it is hard to find a stress function to meet the boundary condition. The R-function theory can solve the problem, and it can be used to describe the complicated cross-section by implicit function form. Introducing the R-function theory can be easy to construct the stress function that satisfied the boundary of the complicated cross-section. A numerical example demonstrates the feasibility and efficiency of the present method.
A Global Residue Harmonic Balance Method for a Class of Nonlinear Jerk Equation
Authors: Xue Xin , Ju Pei Jun , Sun Dan
Published: August 2013

A new approach, namely the global residue harmonic balance, was developed to determine the accurately approximate periodic solution of a class of nonlinear Jerk equation containing velocity times acceleration-squared and velocity. Unlike other improved harmonic balance methods, all the forward harmonic residuals were considered in the present approximation to improve the accuracy. Comparison of the results obtained using this approach with the exact one and the existing results reveals that the high accuracy, simplicity and efficiency of the presented solution procedure. The method can be easily extended to other strongly nonlinear oscillators.
Dynamic Stress Analysis of Coupled Vehicle-Suspension Bridge System in Cross Wind
Authors: Chen Zhi Wei , Li Qi
Published: August 2013

Dynamic stress computation of long suspension bridges under both railway and wind loading is required for either strength or fatigue assessment. However, the effect of dynamic coupling among bridge, railway vehicle and wind on bridge stress response is not well understood. This paper presents a method for predicting bridge dynamic stress responses with coupling effects included. The bridge model (bridge subsystem) and vehicle model (vehicle subsystem) are established using the finite element method, and they are related to each other through wheel-rail contact conditions. The spatial distribution of both buffeting forces and self-excited forces over the bridge deck surface is considered to facilitate the computation of local stress responses. The Tsing Ma suspension bridge in Hong Kong and the data recorded by a Wind and Structural Health Monitoring System (WASHMS) installed in the bridge are utilized as a case study to verify the proposed method to some extent. The railway loading and wind speed measured by the WASHMS are taken as input for the computation simulation. The computed local stress responses are compared with the measured ones. The results from the case study demonstrate that the proposed method could effectively predict the local stress responses of the coupled traffic vehicles and suspension bridge system in cross winds.
Yield Displacement Calculation Method of High-Strength Concrete Shear Wall
Authors: Zhao Hua Jing , Liang Xing Wen , Song Can
Published: August 2013

Considering high compressive strength of high-strength concrete, it is assumed that concrete compressive stress of the cross-section compression zone is linear distribution when the cross-section of high-strength concrete shear wall reaches yield situation. Based on the plane section assumption, the yield curvature formula of shear wall section is obtained by using moment - curvature analysis method. The parameters effecting yield curvature of high-strength concrete shear wall are studied by using the yield curvature formula. The results show that longitudinal reinforced yield strain is the most influencing factor of the yield curvature in addition to axial load ratio. This paper presents yield curvature formula considering the impact of axial load ratio and boundary reinforcement yield stress through the regression analysis of calculation results. On this basis, the vertex yield displacement formula of high-strength concrete shear wall is proposed, and the calculation results of formula correspond to the vertex yield displacement experimental values of the 12 high-strength concrete cantilever wall well.
Application of Mc Composite Retaining Structure in the Silt Soil Foundation
Authors: Cheng Ying , Zhou Ai Zhao
Published: August 2013

This pape combined with the engineering example of a supporting muddy soil foundation pit,used the finite element numerical analysis method, discussed on mechanical deformation characteristics of the cement-soil pile and concrete pile composite retaining structure (MC pile for short ) , Including the effect of section parameters of MC pile on the horizontal displacement of supporting structure, settlement of ground surface and bottom heave. The results show that, MC pile composite retaining structure are beneficial to control the deformation of foundation pit, and increase the stability of foundation pit; M pile retaining wall width to reduce the deformation of the retaining structure has obvious effect, which increase the width of wall can decrease the bending moment ,inclination deformation of supporting structure and lowe bottom heave and surface settlement. Moreover, in the same wall width, there is no C pile to control the deformation of the retaining structure and deformation of the foundation also has a great role.
Program Design of Leveling-Network Conditional Adjustment Based on Transferring Matrix
Authors: Sun Cai Min , Zhou Wen Guo , Sun Guo Qing
Published: August 2013

In a complicated leveling-network, it was often simple to write manually the equations to express all the condition that must be met for a conditional adjustment. Therefore conditional adjustment which was straightforward and regularity in its development and solution.was early becoming very popular . But with the advent of the computer technology, it was gradually reducing its effects which was not well suited to computers for its equations not unique and shapes diversity. Based on this, an available leveling-network conditional adjustment program was developed to solve the problem of conditional diversity. By aid of transferring matrix, the program design scheme of the conditional adjustment was proposed by means of visual basic language platform. The coefficient matrix of the conditional equations was written out based on transferring vectors and arithmetic rules. The normal equations were solved by method from Guassian main column eliminated. The Residuals and the measuring precision was achieved by the results from the normal equation back substituted to conditional equation. The application shows that conditional adjustment by transmitting matrix can simplify procedure of writing the conditional equations, and easily program for conditional adjustment.
Simulation of Orbit Determination of HaiYang-2 Satellite on DORIS
Authors: Kong Qiao Li , Guo Jin Yun , Han Li Tao
Published: August 2013

DORIS is a kind of advanced space-geodetic techniques applied in satellite orbit tracking and measuring. As the first ocean dynamic environmental satellite in China, the HY-2 satellite is equipped with the Doppler orbitography and radiopositioning integrated by satellite (DORIS) tracking system for the precise orbit determination. In particular, the investigation of our work has focused on accuracy analysis of orbit determination using simulated DORIS data given different observation noises, besides the relationship is investigated between accuracy and computation time and the number of ground beacons evenly distributed around the world. Experiment results show that observation noises can affect the accuracy of orbit determination directly, and the number of DORIS ground beacons decides the accuracy and computation time of obit determination in the condition of ground beacons are evenly distributed around the world, therefore, during the process of obit determination, we should optimize the ground beacon station distribution to achieve the best accuracy of obit determination using DORIS tracking data.
Data Processing of IGS Station in China and Analysis of Crustal Movement of Eurasian Plate
Authors: Chen Yong Sheng , He Qun , Chen Jun Yu , Ma Hong Bin
Published: August 2013

By using all 103 days GPS data of IGS in china, from year 2000 to 2005, the baseline is solved with GSMIT software. With One day's baseline solution as the input data, based on the mathematical floating model of station, the floating velocity of station is solved and the crustal movement is gotten; then, according to Euler theorem of plate movement, the Euler vectors of Chinese mainland is obtained; furthermore, the floating velocity of the station area in Eurasian plate is acquired. The results show that, in ITRF2000 framework, the station floating velocity is similar with what announced by IGS and so does the Euler vector, which shows that the continental shelf of China has an accelerated tendency to eastward movement.
The Application of 3D Laser Scanning Technology in Ancient Architecture Protection
Authors: Zhao Jun Lan , Wu Ran , Wang Lei , Wu Yi Qin
Published: August 2013

The study of 3D laser scanning technology in Category Conservation is one of the hot researches in recent years. Through the high-speed laser scanning, catching the 3D data of an object in large-scale with high efficiency, high accuracy and excellent resolution, is a new way in 3D reconstruction and image data acquisition. The method has achieved good results through the experiment.
Identifying the Stay Point Using GPS Trajectory of Taxis
Authors: Xiao Hao , Wang Wen Jun , Zhang Xu
Published: August 2013

With the widespread use of personal mobile communications location-aware devices, a large amount of data of trajectory produced and can be used in information services. These huge amounts of data involves the pattern of human behavior information and cause numerous researchers' research interests. As is known,the key to travel information mining from the trajectory data is the stay point recognition and semantic annotation.Overcoming the shortcomings on adaptability and resistance to noise exists in existed stay points identification methods, and also combined with the basic characteristics of the taxi GPS data,We proposed a way with an parameter optimization stratage to get the stay points from a single trajectory and the figure shows it really works well, with high precision and strong adaptability on the recall ratio and precision ratio.And then,based on this significant achievements,we applies a refined clustering method based on the clustering radius and frequency parameters and get the POI results.
Numerical Simulation of Surface Wind Pressures on Low-Rise Buildings
Authors: Zhao Peng , Dong Heng , Sui Jian
Published: August 2013

This paper mainly studies the distribution characteristics of surface wind pressure on low-rise buildings. Based on the theory of fluid dynamics, this study uses CFD software Fluent 6.3.26 to conduct numerical simulation of the models in wind tunnel tests by Yong Chul Kim involving four working conditions of different spacing or area density in regular arrangement. Compared with data of wind tunnel tests, the results show that different spacing or area density has significant influence on surface wind pressure of low-rise buildings and surrounding buildings have shielding effect over target buildings.
A New Robust Algorithm for Identifying the Orientation of Polygons Containing Arc
Authors: He Yi
Published: August 2013

In this paper, we revisit the problem of identifying the orientation of polygons. After reviewing previous work, we develop further insight into the problem. We then claim that, for a orientable simple polygon, a relationship between the orientation and the sequence of extreme vertices can be found. Building upon this relationship, a novel method is then presented, proved by apagoge, and tested. For the polygons containing circular arc, which the traditional algorithm does not work, a topological preprocessing is developed. The ideas proposed in this paper are simple and effective when used in industry. Experimental results are presented that demonstrate its practicality and efficiency in the manufacturing industry.
An Assessment of Damage to Large-Scale Basement Slab Caused by Groundwater and Expansive Soil
Authors: Peng Jian He , Xie Pin Kang , Dong Bo Ya
Published: August 2013

Cracking damage is a common phenomenon in large-scale concrete structure. But for the underground structure it is not permitted because crack will cause heavily damage and other disasters. With the aid of finite element method for deformation and stress field simulation, a detailed study is carried out for a large area foundation slab of an underground parking lot. The foundation soil condition and the hydrogeological condition are the principal influence factors that result in the cracking problems. The simulation results illustrate that the combined effects of foundation settlement and larger groundwater pressure cause the foundation slab cracking and the existence of expansive soil indeed exacerbates the problem.
Numerical Simulation of the Gas-Power Electromechanical Switch
Authors: Cai Jian Yu , Chen He Juan
Published: August 2013

The gas-power flow resistance-controlled electromechanical switch was a kind of new gas-driven piston-style electromechanical switch used in fuze. It was designed with a flow resistance adjust automatically structure based on the structure of flow resistance-controlled switch. This kind of new switch could adapt to the press change of the input gas to guarantee the stability of the piston movement, and with the piston to the end to turn the switch to achieve the purpose of electronic delay. Firstly, the gas dynamics model of the switch was made according to the structure, Secondly the change of internal gas state and the process of the piston movement were calculated when the rockets was in ballistic phase. Finally, with the similarity model of the switch and digital simulation, the stability of the piston movement and automatic adjustment feature was analyzed.
Design and Implementation of Construction Engineering Teaching System Based Virtual Reality
Authors: Zhang Rui
Published: August 2013

Traditional Construction Engineering education has some shortcomings, such as difficulty to clearly show complicated structure, high cost and period limitation of practice teaching. So the 3D Construction Engineering Teaching System was built based virtual reality (VR). The system was according to real building and integrated many main courses. The system realizes virtual tour, real-time interaction and shows all architectural and structural features by dividing layer and layer. The experiencing model can stimulate students' interest and achieve remarkable effect. Moreover, this puts forward a new idea of curriculum integration for Construction Engineering Training Program. The developmental model based on ProE, 3D MAX and Virtools supplies a new way to research virtual teaching system. The key technology and solution also fit general 3D interactive simulation system.
Study on the Fracture Mechanism of Suspension Insulator String Subjected to Large Wind and its Vibration Control
Authors: Zou Xiang Yan , Xia Chun , Long Wen Yuan
Published: August 2013

This paper deals with a numerical and experimental approach trying to solve some suspension insulator string failure problems, experienced on a quadruple bundle transmission line. The FEM of the system is presented in order to analyze the dynamic behavior of the system. Then an experimental setup is designed according to the similarity by means of FEM analysis. The bending strain level on the insulator string experienced to subspan oscillation is tested in the experimental span, and the frcature mechanism is validated. Finally, the solution adopted to limit the subspan oscillation within safe values is presented and discussed.
Numerical Simulation and Parameter Analysis of Building Vibration Caused by Ground Line of Rail Transit
Authors: Zhang Jing , Zhang Bin , Li Xian Hui
Published: August 2013

Having the entrance/exit depot line of Guogongzhuang metro depot of Beijing metro line 9 as the background, ballasted track-soil model is established and simulated. The accuracy of the model is proved comparatively high. Taking the nearby building as the research object, effects of structure characteristics modification of the building on slab vibration are discussed. The results suggest that: The trend of the vibration levels of slabs changing with the floors is the same as that of the benchmark example after changing the structure characteristics of the building. As the dimension of columns increases and the performance of the concrete is better, the vibration levels of the building decrease obviously. As the thickness of slabs increases, the effect is much more complicated. The vibration level of each slab increases from basement 2 to the 14th floor by 0.02 to 8.4dB. The vibration level of each slab decreases from the 15th floor to the top floor, and the vibration levels are 0.8 to 9.9dB lower than that of the benchmark example.
A Comparison of Numerical Simulation and Scheme for Hull Painting Plant Ventilation Airflow
Authors: Shang Shao Wen , Wang He Feng , Lu Xing Yu
Published: August 2013

The STAR-CCM+ technology is also used to analyze the location and number of vents in hull coating plant in the case of constant air volume. By means of numerical simulation and mathematical model theory, this paper makes a comparison of air distribution in the working area of this plant, and found the interior velocity and temperature field vary with different location and number of vents. Specifically speaking, the lower position and improper number of vents can lead to unevenness of the internal thermal environment and imbalance of wind speed in the working area. This study provides simulated basis and technical references for the better coating operations in suitable environment, which is significant for putting forward the improvement, optimizing the quality of the coating operation and saving energy.
Study of Evaluation Method in Terms of Structural Planes Mechanical Characteristics in Engineering Rock Mass
Authors: Guo Mu Dan , Zhu Fu Sheng , Wang Shu Hong , Mu Xi Jiang
Published: August 2013

Study of mechanical characteristics of structural planes has been significant issue in engineering rock mass stability analysis. The factors that affect the mechanical behavior of structural planes are so complicated that it is quite essential to take an efficient method to quantificationally analyze these factors. Based on the basic principals of analytic hierarchy process (AHP), a structural plane classification method-CSPC method is proposed. It can conduct weight distribution in terms of the complicated factors, assess the structural planes comprehensively and also forecast the planes intensity parameters semiquantitatively. The classification and forecast parameters of structural planes appropriately fit the cases in engineering. Furthermore, the method is easy to master for the engineers and the application can be of great prospect.
The Studying Fabrication and Application of the Multifunctional Frozen Triaxial Test Apparatus
Authors: Zhang Shi Yin
Published: August 2013

The frozen soil triaxial test apparatus is the basic equipment to study the mechanics property of the frozen soil. According to the norm of frozen soil test and the construction character of the present mine, the high-performance frozen soil triaxial test apparatus is made which could be used for many type tests, such as the static triaxial shear test, the dynamic triaxial test, the triaxial creep test, the routine triaxial strain route test, the routine triaxial proportion coordination test, the routine triaxial recycle load test, the routine triaxial concretion test and so on. The apparatus can realize the high surround pressure. During the test progress, the test parameter can be set up and the test date can be collected by the computer. The frozen soil triaxial test apparatus is a new type triaxial test apparatus.
Geo-Stress Measurement and its Application in the Yangchangwan Coal Mine
Authors: Zhang Xiao Yu , Liu Feng Ming , Chen Gang
Published: August 2013

The initial stress of rock is a basic parameter, which can be used for surrounding rock stability analysis, exploitation and support design. By utilizing stress relief method of hollow inclusion with its characters of high precision and obtaining three dimensional stress at one time, we have measured three dimensional stress magnitude and direction in north wing roadway (-850m) and 710 open-off cut (-1000m), respectively. The results show that the horizontal tectonic stress is obvious in this coal area.
The Application for Reinforced Concrete Piles of Marine Sedimentary Soft Soil Foundation Treatment
Authors: Du Yang , Chen Tao , Li Song
Published: August 2013

Marine sedimentary soft soil is larger water content, higher compressibility, and lower strength and buried deep. The sluice project in the marine soft soil foundation construction is beneficial to the people's livelihood needs to conduct foundation treatment. Through the scheme comparison, the sluice wing wall is located in the Yellow River estuary uses reinforced concrete pile to treat foundation. The pile diameter is 0.5m, the pile length is 19m, and the pile end is located in the sand to meet the requirements of various conditions.
Numerical Simulation Research on the Mechanical Process of Pile-Anchor Retaining Deep Building Foundation Pit
Authors: Shan Bao Xue , Liu Lu Chao , Wei Cui
Published: August 2013

In this paper, based on an actual pit excavation project, the mechanical process of excavating and retaining is simulated. Combined with the monitoring data, the stress, displacement of soil and internal force of retaining structures are analyzed, and the characteristics of deformation and force are summarized. This research offers references for safe and economical design and construction, and helps to improve the design theory of foundation pit support.
Research of the Dynamic Compaction Effective Reinforcement Depth of Cohesionless Soil
Authors: Song Xiu Guang , Yang Yang , Wu Qing Dong , Zhou Zhi Dong
Published: August 2013

The effective reinforcement depth is one of the most important parameters of dynamic compaction method design and construction, so far it is still lack of in-depth theoretical study. In this paper, combined with the field test, FLAC3D was used to do the numerical simulation of dynamic compaction reinforcement to cohesionless soil. By the simulation, this paper analyzed the factors which may influence the effective reinforcement depth, such as the hammers weight, drop distance, base area, and the soil parameters. The orthogonal design method was used to analyze the soil parameters sensitivity to the effective reinforcement depth. Combined with the results of numerical analysis and the traditional empirical formulae, the effective reinforcement depth calculation formula was established for cohesionless soil. Engineering verification shows that, the results estimated by the formula is reliable, and can provide certain reference for the future engineering.
An Observation and Analysis of Passenger Dedicated Line Subgrade in Coastal Soft Soil Zone
Authors: Yang Yi Ling , Yang Long Cai
Published: August 2013

Nanjing-Hangzhou Railway Passenger Dedicated Line is a high-speed railway of the speed 350 km/h in coastal soft area without railway track ballast. The settlement of soft foundation is quite great and the strict control standards of the settlement after construction of the high-speed railway that the settlement observation in construction phase is very strict. Through the settlement observation data analysis of Nanjing-Hangzhou Railway Passenger Dedicated Line on-site, the author found that the preloading can rapidly accelerate the settlement of the soft soil subsidence, the settlement is quite great during the embankment construction and the later three months, there is a preloading critical height, the foundation generally does not rebound when load was removed, the settlement trends are consistent with the three-point analysis. These conclusions are certain referential significance for the settlement control of the coastal soft soil area of high-speed passenger dedicated .
An Analytical Solution to Temperature Distribution of Single-Row-Piped Freezing with Different Pipe Surface Temperatures
Authors: Hu Xiang Dong , Zhang Luo Yu , Han Yan Guang
Published: August 2013

Artificial ground freezing method is now widely used in many kinds of municipal projects. The existing formulas to calculate the temperature field distribution of single-row piped freezing are all based on the conditions that the temperature of all freezing pipes are equivalent. In this paper, analytical solution to steady-state temperature field of single-row piped freezing with different adjacent pipe surface temperatures was derived based on thermal potential superposition method. And discussions are made to analyze the influence of temperature difference between adjacent pipes and freezing time on temperature distribution of frozen soil.
Study on Rock Mechanics in Stability State of Kangding Substation
Authors: Guo Qian , Li Yu Sheng , Wang Lei
Published: August 2013

This paper uses finite element numerical simulation method to analyze the rock mass stress deformation characteristic and it illustrates that site stress state is mainly controlled by the gravitational field, while the rock basic deformation is solidification. On the foundation of blocks limit equilibrium calculation results, it shows that the global stability of the site is in good condition in a variety of extreme circumstance conditions. The blocks stability is slightly lower than sites whole stability, which is in the front edge of the site, controlled by secondary slip surface II.
Influence Study of Confining Pressure on the Dynamic Parameters of the Silty Clay
Authors: Shen Qiong , Cai Cong , Mo Qing Cheng , Tian Yong Ding , Zhu Zhan Yuan
Published: August 2013

The dynamic parameters of silty clay in Dujiangyan under dynamic loading are studied with RCA resonant column apparatus made in GDS Company of British with different confining pressures. The results show that: The test process can be reproducible; the maximum dynamic shear modulus and damping ratio are increasing, and the shear strain amplitude is decreasing with increasing confining pressures. The empirical formula of the dynamic parameters of silty clay in Dujiangyan vs. confining pressures is formed. The study can provide basic data for seismic dynamic response analysis of soil.
Strength Attenuation Law of Damaged Rock Samples and its Structure Effect
Authors: Su Hai Jian , Jing Hong Wen , Wang Chen , Meng Bo
Published: August 2013

In order to study the post-peak mechanics behavior of rock samples with a thick wall cylinder structure, damaged rock samples were precast with a new method. The uniaxial compression tests and tri-axial compression tests were conducted on the samples and the test results were compared with that of complete rock samples. The results show that strength attenuation value of the damaged samples increased with the confining pressure and the specific relationship was obtained by nonlinear fitting as (is the strength attenuation value and is the confining pressure); destructiveness of damaged samples was more serious than the complete ones; a new nearly horizontal failure phenomenon appeared under the tri-axial compression and it was more general with the increase of confining pressure. Structure effect of uniaxial strength attenuation was revealed based on the particle flow software system (PFC) and the corresponding theoretical model was found as (is the strength attenuation value under uniaxial compression of any damaged sample with a thick wall cylinder structure; is the strength attenuation value of standard damaged samples under uniaxial compression; is the structure ratio, and are the parameters of the material). Characteristic value of the strength attenuation value under uniaxial compression was obtained by calculation when the structure ratio was indefinitely large.
The Study on Failure Mechanism of 3D Cracked Rock Mass under Fissure Water Pressure
Authors: Xue Wei Qiang , Zhu Wei Shen , Zhang Dun Fu , Fu Jin Wei
Published: August 2013

In this paper, the failure mechanism of rock-like specimens with built-in 3D double cracks under fissure water pressure was numerically investigated. The initiation and propagation process of secondary cracks under fissure water pressure was simulated by using the modified elasto-brittle model and the superfine meshing method in the FLAC3D program. The fluid-solid coupling in cracked rock masses was preliminarily studied. Some of the simulation results are in good agreement with the previous results tested by scholars.
Slope Deformation Prediction Based on Chaotic-SVM
Authors: Jia Lei , Li Yuan , Xie Yong Ping
Published: August 2013

This paper principally studies the prediction of slope deformation based on Support Vector Machine (SVM). To explore the prediction process, phase space is reconstructed. The geological body’s displacement data obtained from chaotic time series are used as SVM’s training samples. Slope displacement caused by multivariable coupling is predicted by means of single variable. Results show that this model is of high fitting accuracy and generalization, and provides reference for deformation prediction in slope engineering.
Sensitivity Analysis of Shear Stress between the Landslide and Pile
Authors: Qiang Pei , Lei Huan Zhen
Published: August 2013

There are many factors which can affect the mechanical properties of interface .Targeted research about effect anti-slide pile design parameters act on the contact stress is carried out in this paper. Based on the specific slope example and the principle of orthogonal experiment, the effect that the pile spacing (s), pile cross section width (b), pile cross section length/ width (h/b), the pile length (L) conduct on the maximum shear stress between the landslide and anti-slide pile is thoroughly discussed by combining with orthogonal design method and numerical simulation organically. The results show that (1) The order of influence factors respectively is L, S, b, h / b for the maximum shear stress on interface in the front of pile, and it is L, b, S, h / b for the maximum shear stress on behind of pile;(2) L is the main factor that affects the maximum shear stress on the interface between anti-slide pile and soil;(3) Effect about S and L acting on maximum shear stress of the interface respectively is significant and very significant; h/b has no significant effect on maximum shear stress of the interface.
Simulation and Application of Rock Fracture Mechanics Model
Authors: Wu Ya Guang , Zou Lei Lei
Published: August 2013

This paper study a discontinuum model on the rock mass, which represented by an assembly of jointed elements and a fracture is initiated when the stress in the joint between two elements exceeds a critical value. The rock fracture mechanics model in this paper show that the continuum damage mechanics is based on the fact that the brittle rock has pre-existing defects, and the material failure is a process of growth and nucleation of these defects.
Research Progress and Development of CFG Pile Composite Foundation
Authors: Xing Shuo , Wang Yun Xia
Published: August 2013

This paper introduces the present research and observes the future research of CFG pile composite foundation.
Study on Effect of Gradient of Landfill Side Slope on Tensile Force of Geosynthetic Liner
Authors: Li Ming Fei , Ren Yi Nan , Fan He , Ning Bao Kuan
Published: August 2013

It is important to study the effect of gradient of landfill side slope on the tensile force of geosynthetic liner in order to assure adequate performance and to increase the landfill volume. In this research, for the landfill liner composed of upper protective mat, barrier sheet and bottom protective mat, finite Element Analysis, in which the gradient of modelled landfill side slope was changed from 1:2.0 to vertical, were conducted to evaluate the effect of side slope gradient on the tensile force of geosynthetic liner. In the FEM analysis, the stress-strain relationship of ash and friction stress-relative displacement relationship of joint element were modelled by hyperbola. The results of centrifugal model experiments were also used to verify the FEM analysis. As a conclusion, the tensile force of geosynthetic liner at the slope crest decreases with increasing side slope gradient from 1:2.0 to 1:0.2 and then it increases slightly as the gradient increases up to vertical.