bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact Assessment of Common Supported Excavation of Double Foundation Pits on the Adjacent Tunnel
Authors: Shen Hui , Bi Jin Feng , Luo Xian Qi
Published: June 2012

Based on the deep excavation engineering which used the common support design near the range of Suzhou Rail Transit Line 2, a 3-D numerical model was created to make the numerical simulation analysis of the deep foundation pit construction and obtain the comprehensive evaluation of the influence on the nearby subway tunnel stress and deformation when the 3 # and 4 # block foundation pits were excavated. The numerical results show that: when the pits are excavated to the basement, the total displacement value of the tunnel is 1.6mm. Because of the aspect ratio difference between the 3# and 4# block pits, the subway tunnel displacement of every direction trends to the 3# block. And the preserving soil area between the two blocks makes the tunnel stress present a symmetric distribution along the soil area's cross section. The surface settlements of soil behind enclosure structure lead to a great impact on the pipelines, whose maximum reaches 5mm. For comprehensive, the maximum displacement and spring back deformation of the subway tunnel meet the control requirements, with a certain margin of safety.
Discussion about Train-Induced Ground Vibration
Authors: Liang Chang
Published: June 2012

The building vibration induced by train loads has aroused people’s great attention. Many investigations have been carried out by many researches in order to evaluate the effect of train-induced vibration on environment. But they have not shown the reason why enlarged vibration region exist in front of a building. In this paper, building structure vibration induced by train loads was analyzed by numerical simulation method performed by ANSYS. Based on numerical results, it’s concluded that the reason for this phenomenon that enlarged vibration region may exist in front of a building is the result that incident wave and the reflected wave superpose mutually. Subsequently, the influence of barrier depth on the enlarged vibration region is also discussed.
Short-Distance Undercrossing of Shield Tunneling on Existent Tunnel in Soft Soil Area
Authors: Cao Yong Hua , Kou Xiao Qiang
Published: June 2012

In urban environment, short-distance undercrossing of shield tunneling to an existent tunnel is an unloading process and can cause adverse effect on the existent tunnel. This kind of effect should be controlled. To analysis and control this effect, numerical simulation, field monitoring and optimization of construction parameter are used. To get reasonable calculation parameters for numerical models, field monitoring is conducted. The numerical simulation is utilized to study the process of short-distance undercrossing. The simulation result revealed that the deformation of the existent tunnel can be beyond the tolerable value unless some measure is adopted, but the deformation can be reduced significantly by improving the ground under the existent tunnel with cement deep mixing method. Construction measures are adopted, such as the strict controlling of synchronized grouting, secondary grouting, rotation speed of cutter head and driving speed. As a result, the deformation of the existent tunnel is controlled in the tolerable value.
Comparison Analysis on Construction Methods of Yuzhou Tunnel In Situ Expansion Project
Authors: Yu Hai Xiang , Chen Xiao Yang , Chen Qin
Published: June 2012

According to the Yuzhou Tunnel of Chongqing Airport Road in-situ expansion project under the IV and V class surrounding rock, this paper compares the construction mechanism among the three construction methods which can be used in the project. The results based on the construction mechanism analysis under different construction methods show that, it’s suitable to use bench method in the IV class surrounding rock and backfill method in the V class surrounding rock.
Multiple Source-Detector Reflected Wave Method in the Intercity High-Speed Rail Tunnel Application
Authors: Liu Xiang Hong , Zhang Ping Song , Sun Lin Hua , Chen Song
Published: June 2012

In the tunnel excavation process, often encounter fault belt, soft interlayer and abnormal water-bearing body does not directly predict adverse geological structure, not timely prediction and control these geological disasters will affect the safety of production. In many prediction methods in geophysical technology with nondestructive, accurate, efficient, fast and be recognized, many shot-geophone reflected wave method in different geological conditions on the apparent impedance response, the migrated results can accurately distinguish the lithologic interface, in many projects has been confirmed. The paper introduces the multiple source-detector reflection wave observation system based on, combined with the specific project example, elaborated how the shot-receiver reflected wave method in tunnel face geological disaster prediction in rats.
The Study on the Construction Technology of Large-Scale Underground Interchange Tunnels under the Rivers
Authors: Zhu Gen Qiao , Lin Zhi
Published: June 2012

A Large-scale underground interchange tunnels will be applied in the Chongqing Two Rivers Tunnel project with six crossings and four interchanges adopting NATM. The paper analyzes and discusses the whole-process construction mechanical behavior of the underground interchange by the numerical analysis method, at the same time considering the similar project established, and then suggests some important design parameters about crossings and close overlap interchanges between NATM tunnels, such as proper space of crossings and interchanges. Through the analyses, the paper suggests the design and construction method and construction organization project, especially for the crossings and close overlap interchanges between the NATM tunnels. The paper discusses the key problems of an underground interchange tunnels, and first suggests a mode how to construct an underground interchange tunnels. So, it is important in theory and practical engineering.
Highway Tunnel Comprehensive Detection Technology Research and the Application
Authors: Zhang Jin , Yang Ze Ping , Su Tian Ming
Published: June 2012

According to the characteristics of tunnel anchor now，the analysis of test means of the tunnel at present stage，put forward in different conditions, the most appropriate anchor test method and the verification method corresponding，to make up for the defect of the single detection method, make tunnel test results more scientific. Introduction
Design of Underground Coal Mine Refuge Chamber
Authors: Yang Xiu Dong , Jin Long Zhe
Published: June 2012

In recent several years, coal mine tragedies had happened frequently in Chinese, a minimum life sustaining atmosphere would need to be developed to design any sort of refuge chamber for entrapped miners to await mine rescue teams. Parameters such as oxygen consumption rate, carbon dioxide exhalation rate, and maximum allowable temperatures inside such a chamber for human survival had to be defined.
Finite Element Analysis of the Construction of the Subway Tunnel Test Section below through the Railway Bridges
Authors: Huo Run Ke , Lun Pei Yuan , Yao Yong Zhen , Li Jie
Published: June 2012

During the construction of city subway, it often needs to cross under the existing buildings, which will have some influence on these buildings. The article, taking the engineering of subway tunnel in Harbin city for example, uses finite element analysis software to simulate the dynamic excavation of the tunnel, and combines with the measured data of actual monitoring, analyzes the primary support structure stability in the process of tunnel excavation. Finally it draws the conclusion that the stress and displacement near the working face change greatly, the springback displacement of tunnel bottom is big, fracture surface near the entrance of the hole tends to be stable with the excavate of the working face.
Strip Insulating Layer in Tunnel in Cold Region and its Temperature Field Analysis
Authors: Lu Kang Cheng , Ma Chao Chao , Ji Zhe , Xu Peng
Published: June 2012

Strict waterproof is the key to prevent frost damage to tunnel in the cold region. Improving drainage system has benefits to obtain good waterproof effect. Aim at the drain pipe freeze in cooling and warming period, we design a strip partial insulating layer to the drainage system :(1) The girth drainage pipe connects to the central drainage pipe directly, and the lengthways drainage pipe connects to the girth drainage pipe by tee. (2) Interval decorating insulation layer to the tunnel girth drainage pipe, using the strip insulation layer behind the lining and setting annular insulation around drainage pipe under the tunnel road. (3) The strip insulation layer is sandwiched by two layers of flashing; one of them forms a whole system with the tunnel flashing and the other posts on its surface. The temperature field finite element analysis of surrounding rock and lining concrete show that: As the girth drainage pipe if there is insulation layer is placed with a certain interval between each other. Two kinds of drain pipe's freeze-thaw state has a time gap. It is beneficial to solve the problem of the poor drainage after the lining in the cooling and warming period.
Study on Structural Design of Loess Tunnel with Large Transection and its Construction Method in the Expressway from Datong to Hunyuan
Authors: Zhou Xiao Jun , Wang Zhi Yuan , Fan Yin Hua
Published: June 2012

According to the engineering geological and hydrogeological condition of loess tunnel with large transection in the expressway from Datong to Hunyuan, and on the basis of the planned running speed of motorized vehicles in the loess tunnel, the excogitative parameters of tunnel support for relevant surrounding rock and its driving method have been put forth in this paper. The application of the presented new construction method for expressway loess tunnel has accomplished a great success.
Numerical Simulation for the Safety of Release Hole at Lower Position of Cavity in Tunnel
Authors: Li Cheng Wei , Wen Guo Jun
Published: June 2012

The energy release and depressurization method is often used for the hidden cavity with extra big mass and high pressure in a tunnel. It is critical to determine the minimal depth of safe overburden for the release hole at lower position and the pressure at high position to be released. According to actual data collected from a cavity of Maluqing tunnel of Hubei, this paper performs the computer simulation and analysis for the safety of the release hole at lower position in the cavity and determines the critical safe depth to disclose the cavity is determined tentatively by using the finite differential software of FLAC3D. The simulated results in accord well with the actual situation show the rationality and validity of this numerical simulation.
Design of Underground Engineering Analogy Based on Fuzzy Comprehensive Evaluation Model
Authors: Lei Jin Sheng , Jin Zheng Tao , Bao Lei , Wen Liang
Published: June 2012

In the design of underground engineering analogy, the division of rock mass level and the selection of support parameters are affected by many uncertain factors which share characteristics of random and obscurity. This paper lays the foundation of the classification of joint rock masses CSIR and supporting parameters recommended values, selecting several key factors affecting the stability of surrounding rock masses, and employing the methods of fuzzy comprehensive evaluation to divide the underground cavern, and having put forward the reasonable supporting parameters. The results show that the level of surrounding rock is the Ⅲ, meanwhile, it takes into account the proximity effects and designs the supporting parameters to the supports, as a result, this method has achieved comparatively reasonable and economic effects in the practical application.
Coupled Fluid-Mechanical Analysis of Deep Tunnel in Water-Soaked Karst Stratum
Authors: Li Xun , He Chuan , Xu Guo Wen
Published: June 2012

To reduce the impact on water resource and the environment, the ‘controlled drainage principle’ is complied with when designing waterproof and drainage system of tunnel in recent years. For deep tunnel in Water-soaked Karst Stratum, the lining would sustain high water pressure that was caused by the unreasonable design of waterproof and drainage system. Taking a railway shield tunnel as an engineering background, the water shut-off effect of grouting circle, minimum controlled discharge of tunnel and the water pressure of lining properties were studied. The results indicated that, under the condition of high initial water pressure and adequate groundwater recharge, to achieve the desired water shut-off effect, the permeability coefficient of grouting circle should be less than that of surrounding rock over one quantitative grade; the water pressure of lining decreased with the increase of discharge, and showed a linear relationship; the lining could meet the requirement on the design water pressure load, when the permeability coefficient of grouting circle less than 1/20 of the surrounding rock’s, and the controlled discharge greater than or equal 1/2 of uncontrolled discharge; the full-sealing waterproof lining would sustain initial water pressure and the calculation value of water pressure couldn’t be discounted, if the grouting wasn’t waterproof.
Study on Acoustic Emission of Rock Damage Based on Physical Cellular Automata
Authors: Ma Zhi Tao , Wang Yong Ping , Liang Sai Jiang , Gao Dong Chuan
Published: June 2012

Rock acoustic emission a physical phenomenon during the rock deformation, it is also an effective method used to study the properties of rock damage. In this article, from the aspects of elastic energy, a discrete nonlinear dynamics analysis method was established based on physical cellular automata. Using this new method, the properties of acoustic emission during the rock deformation and damage were studied, and the results were compared with related previous research achievements, and the results show that this new method based on cellular automata is reasonable and effective.
Effective Length of DJM Pile Composite Foundation in Loess Hilly Areas
Authors: Cui Peng Ju , Peng Xiao Yun
Published: June 2012

Based on the loading test of a jet pile composite foundation in loess ravine area, the relationship between the pile capacity and its length was researched. The effective length of the pile and the suitable range of pile length in this region were given in this paper. In the end, it indicates that only the magnitude of current can’t be use to control the length of the pile at construction.
Research on Immersion by Shifosi Reservoir Retain Water Based on Fuzzy Comprehensive Evaluation
Authors: Pan Jun , Leng Te
Published: June 2012

Shifosi reservoir is a collection of flood control and urban water supply function in one of the plain reservoir. After reservoir water built, the surrounding residential and agricultural cultivated land produced serious phenomenon of immersion. In order to solve the environmental geological disaster problems caused by Shifosi reservoir retain water, this paper uses the fuzzy comprehensive evaluation method to evaluate the immersion. It used fuzzy math theory and analysed the produce condition of reservoir immersion, then built the immersion grade evaluation target system and standard value , and maked out the estimating index weight with analytic hierarchy process, which influence immersion grade. According to the evaluation results, puts forward well pumping water solution, and finally achieve control ling the phenomenon of immersion ,at the same time pumping groundwater can be as Shenyang water supply sources. To achieve the effect of kill two birds with one stone. On this study of Shifosi reservoir immersion to solve engineering problems and provide the scientific and feasible basis. This study selected of evaluation factors immersion degree. Evaluation standards to similar problems of great reference value, and for immersion degree of evaluation has provided a new way.
Numerical Study on Flow around Three Circular Piers in Tandem Arrangement at a Supercritical Reynolds Number
Authors: Hao Peng , Li Guo Dong , Yang Lan , Chen Gang
Published: June 2012

As the support structures of building for crossing river, piers of bridge and/or aqueduct are generally arranged in tandem along the river direction, the fluid dynamic forces are main lateral loads acting on the Piers. Two-dimensional fluid computations have been performed using LES model to investigate the flows around three circular piers in tandem arrangements at a supercritical Reynolds number, Re =8.76×106. Both center-to-center spaces are L/D=2.6. The flows and fluid-dynamic forces obtained from the simulations are analyzed. The results can provide the basis for the dynamic design of the supporting structures of the aqueducts.
Finite Element Simulation of Excavation and Supporting of Karl Valley Quarry at Pubugou Hydropower Project
Authors: Xu Guo Zhang , Zeng Yi Pei , He Meng Zhu
Published: June 2012

Karl Valley Quarry is the main quarry for the construction of the Pubugou Hydropower Project. With its developed faults ,veins ,dense joint-relief zones, deep pressure-relief zones and fissure, the slope has the possibility of integral and partial instability in the densely blasting and excavating process).Based on the rock elastic-plastic equivalent constitutive relations of joint-anchoring, by using the elastic-plastic element finite element method, the slope excavation and reinforcement as well as the stability is numerically simulated and analyzed. In addition, the reasonability of the initially drafted schemes for construction sequences and anchoring are evaluated and some valuable and instructive suggestions have been proposed to the engineering construction relevantly.
Green Function Cloud Computing Representation with Free Water Surface
Authors: Li Xue Jiao , Wang Xing , Liu Chao , Li Meng Yu , Zhang She Sheng
Published: June 2012

According to the convenient using principle of cloud computation, the control equation and boundary condition of point source with free water surface are considered, the basic analyzing solution is obtained, the Green function representation is discussed., the discrete calculation expression and calculation procedure are proposed, two-dimensional graphics of the Green function’s real and imaginary part are plotted.
Stability Research of Lanan Rock-Fill Dam Based on Limit Equilibrium Method
Authors: Pang Lin Xiang , Qiao Lan , Li Yuan
Published: June 2012

There are corresponding stability criterions for limit equilibrium method, which is simple to implement and has been used for long-term. But this method is only considered the equilibrium of system without considering deformation, compatibility conditions and material constitutive. To improve the method, which is used to analysis the stability of Lanna dam, was proposed to optimize the boundary conditions, consider the discontinuity between the media in junction and add additional stress to consider the effects of buoyancy and seepage. After completion, tests showed that this approach could overcome limit equilibrium method’s shortcoming and describe the discontinuous characteristics of media naturally, such as dislocation, opening, slip and so on. And the result is reliable.
Seepage Calculation and Analysis of the Upstream Earth-Rock Cofferdam of the Pinecone Hydropower Station
Authors: Fan Yun Yun , Tang Chuan , Wang En Zhi
Published: June 2012

The upstream cofferdam of the Pinecone Hydropower Station was an upstream earth-rock cofferdam built on the deep overburden layer of upstream foundation pit, which has many characteristics such as big reservoir capacity in front of the cofferdam, deep foundation pit behind the cofferdam and long anti-seepage time. In order to provide reference and a basis for seepage control construction, the sensitivity analysis on permeability coefficients of the seepage control system was made to analyze the seepage characteristics of upstream cofferdam at design water level and to discuss the permissible value range of permeability coefficients. The calculation results show that correct and reasonable seepage control measures are able to realize an effective control of the seepage field. Besides, the engineering design parameters are obtained when the optimization analysis on permeability coefficients meets the seepage control requirements, and thus provide the basis for engineering optimization design.
Numerical Simulation of Flow on Stepped Spillway Combined with Wide Tailing Piers and Stilling Basin
Authors: Wei W.L. , Lv B. , Liu Y.L. , Yang X.F.
Published: June 2012

In this paper, a two-phase flow model combined with the Realizable k–ε turbulence model was used to simulate hydraulic characteristics of two-type dissipaters: the stepped spillway combined with stilling pool and the stepped spillway combined with wide tailing pier and stilling pool. The distributions of physical parameters, such as velocity field, pressure field, turbulence kinetic energy and turbulence dissipation rate were obtained. The grid was generated by using the regional division method, the unstructured grids used for the irregular and complex parts and the structured grids for the regular and simple parts, and the grid density is arranged according to the flow gradient size. The finite volume method was adopted to discretized the control equations; and the VOF method was adopted to deal with the free water surface; and the PISO algorithm was used to solve the velocity and pressure coupling equations. A comparative analysis of the two energy-dissipators in the velocity field, pressure field, turbulence kinetic energy and turbulence kinetic energy dissipation rate shows that the dissipation of overflow for a stepped spillway together with wide tailing piers and a stilling pool jointing energy dissipator is better than that with pier situation.
A Study on Scouring Laws Downstream of Debris Flow Sabo Dams
Authors: Pan Hua Li , Huang Jiang Cheng , Wei Li Qin , Ou Guo Qiang
Published: June 2012

Debris flow sabo dam is one of the most widely used debris flow control engineering. Its stability and safety operation is a key to controlling the effect of hazard prevention and avoiding secondary hazard. Because of the particularity of debris flow, it’s very hard to observe the process and morphology directly by field investigation. Although the scouring depth calculation method in hydraulic engineering provide an idea for debris flow sabo dam, but it can’t be used directly for the calculation of scouring depth downstream of debris flow sabo dams and foundation designation of the control engineering. This paper analyzed the influence factors of scouring laws downstream of debris flow sabo dams and the research status home and abroad. It suggests studying the scouring process and laws downstream of debris flow sabo dams by theoretical analysis, mechanical analysis and energy method combined with simulation experiments, establishing quantitative relationship between the scouring laws, limited depth, morphology, sediment transportation characteristics and the feature parameters of debris flow.
Stability Analysis of Diversion Tunnel Inlet Slope at Right Bank of Jinchuan Hydropower Station
Authors: Tang Liang Qin , Li Yong Jian , Nie De Xin , Liu Dong Yan
Published: June 2012

Based on the research of formation lithology, geological structure, deformation failure mechanism ,rock-mass quality and mechanics parameters of the diversion tunnel inlet slope at the right bank of Jinchuan Hydropower Station, a numerical three-dimensional geological model of slope and structural surface was established by applying 3D modeling program, and combined with the slope excavation design, cuttings of transverse and axial direction are conducted, thus, the structural surface location and the rock-block combination are obtained in the excavation face and excavation process. And then, the stability of deterministic block body is calculated by using commercial rock-slope stability-calculation program. By using the probability analysis method in analysis of dominant structure plane combination, possible random combination block of the rock can be get, and then, the block stability calculation is carried out. The results show that deterministic blocks and random combination blocks have good stability under all kinds of working conditions.
A Study on Seawater Intrusion Prevention Measures and Comprehensive Governing Pattern
Authors: Li Xiang Ran , Han Gang , Cong Ri Jiang
Published: June 2012

The seawater intrusion is a kind of comparatively common natrual geological disaster around the coast area. In order to solve this sort of geological disaster, scholars both home and abroad have been doing quite a large amount of work to find out the cause of the disaster and the methods of its prevention. Among all of these work, the research of Yantai seawater intrusion comprehensive governance is one of the most typical. We take Yantai for instance, studying both engineering and management measures of the prevention of seawater intrusion, while at the same time exploring and discussing the pattern of the prevention of seawater intrusion by integrating "point, line and all the aspects" comprehensively, which produces quite outstanding results.
The Framework Research of Dam Safety Monitor Multiple Models Analysis System in Computer
Authors: Zhang Han , Chen Jian Kang , Wu Zhen Yu , Wang Wei Nan
Published: June 2012

The thesis probed and introduced that the selecting of programming language and the choice of monitor analysis mathematic model trussed on multiple models according to the merit and demerit of the selected mathematic model and combining the computer language feature so that the most effective mathematic model was selected in monitor data analysis and the rationality of data analysis was increased in the weaving of dam safety monitor analysis soft ,meanwhile, it increased the precision of prediction, and it made that common operating staff could do that in operating and using.
Groundwater Quality Variation Affected by Artificial Recharge in Hutuo River Bed
Authors: Du Shang Hai
Published: June 2012

Artificial recharge using outside diversion water is an effective method to solve the water resources shortage, but it’s necessary of groundwater quality analysis during the recharge process. For the parameters acquisition of artificial recharge, a field infiltration test had been taken with the Hutuo River bed, the ions variation had been tested. The results show that, Cl-, SO42-, F- increase but NO3- decreases during the recharge process, then get back after the recharge termination; considering mixture is main factor of Cl- variation, the proportions of different water resource had been calculated, the proportion of recharge water increases during artificial process and decrease after the recharge termination, hysteresis exists between different sampling wells by the responding time and peak time.
Stability on Supporting Structure of Deep Foundation Pit with Infiltration
Authors: Gao Xue Song , Dong Jian Jun , Zhao Xu , Yin Peng Yang , Lv Shao Hua
Published: June 2012

The FLAC3D was used to the fluid-solid coupling numerical simulation of considering the initial state of unsaturated to soil for the deep foundation pit engineering under different rainfall infiltration conditions. By comparing the bending moment, the shearing stress and internal forces of support under the infiltration conditions between non-rainfall and rainfall, the paper focus on the stability of deep foundation pit. Research on the stability of deep excavation under rainfall conditions was a useful attempt. From the detail study of the stability of a foundation pit of Qinhuangdao under rainfall infiltration conditions, the paper have drawn some useful conclusion on the design of building foundation pit, which can be the basis of excavation design and construction under rainfall conditions.
Study on Stress and Distribution of Curved Channel through Experiment
Authors: Wang Ri Sheng , Shi Kai
Published: June 2012

The doppler velocity apparatus of the data collected on the corners river water cut stress in the system were studied. According to the test data, this paper analyzes the different working conditions river bend by shear stress, and draw a conclusion
Study on Resistance of Marine Silica-Fume Concrete in both Frost-Thaw Cycles and Chloride Penetration and its Microstructure (Part II)
Authors: Yang Wen Wu , Qian Jue Shi
Published: June 2012

A study was made from both macro and micro aspects into the resistance in frost-thaw cycles and chloride penetration of silica-fume concrete by simulating the characteristics of the marine environment and using the R-value evaluation method, MIP and SEM experiments. after concrete is under frost and thaw cycles by the erosion of seawater, the levels of the most probable pore radius and total porosity have a certain law of varying with the level of R-value, among which, an obvious relation of correspondence in a inverse proportion exists; the concrete mixed with silica fume has a poor ability of SO42− penetration resistance; the amount and types of superficial and internal corrosive products can reflect the reason of difference in concrete R-value, that is, when the R-value is high, the amount and types of superficial corrosive products are more than that of internal corrosive products. MIP and SEM micro analytical results can prove the macro conclusion of R-value evaluation method.
The Enhancement Effect Analysis of Pile-Base Post-Grouting Piles
Authors: Zhang Rui Kun , Shi Ming Lei , Zhang Hao , Wang Jin
Published: June 2012

The pile-base post-grouting technology can solve the bottom slime and the shaft mud-cake which are the two principal deterioration factors of slurry bored piles. The enhancement effect of pile-base post-grouting was analyzed through the comparison static loading tests and summarization of literature data. The hysteretic nature of the enhancement effect was revealed and the abnormal phenomena was analyzed that the initial loading stiffness of deep pile with post-grouting was lower compared with the pile without post-grouting. The settlement-reducing effect of post-grouting is limited at serviceability limit states and the additional settlement effect of end resistance enhancement of pile with post-grouting is proposed.
The Vibro-Acoustic Characteristics of the Cylindrical Shell Partially Submerged in the Fluid
Authors: Ye Wen Bing , Li Tian Yun , Zhu Xiang
Published: June 2012

The characteristics of the sound radiation and vibrational power flow of the partially submerged cylindrical shell under a harmonic excitation are studied. The approximate acoustic boundary of the free surface is used to solve the fluid domain. The structure-fluid coupling equation is established based on the Flügge and Helmholtz theories. The far-field sound pressure is calculated and compared with that in infinite field. It is found that the far-field sound pressure presents large gap in different immersion status in the presence of the free surface while the results of the input power flow in these cases have less differences.
Review on Rock Joint Contact Model
Authors: Zou Li Fang , Deng Wei Jie
Published: June 2012

The contact of nominally flat rough surfaces can be applied in rock joint contact problems. Statistical, fractal and multi-scale models for surfaces under normal loading are reviewed. The assumptions usually used in those contact models are illustrated. The criteria for distinguishing surfaces which touch elastically from those which touch plastically are analyzed. Moreover, the interaction effect of asperities under loading is discussed.
Water Balance Optimization of Non-Traditional Water Resources Utilization in Green Building Based on Landscape Water Regulation Function
Authors: Chai Hong Xiang , Deng Ke , Zhao Fang
Published: June 2012

According to the extremely uneven situation of monthly rainfall in China, in order to both improve utilization efficiency of non-traditional water resources and realize economy applicable in green residential districts, an optimization method of monthly water dynamic balance of non-traditional water resources utilization in green building based on landscape water regulation function was put forward. The optimization method was made full use of large capacity of landscape water regulation function, combined with monthly water consumption law between supply and demand of non-traditional water resources in districts. And this method was applied in a green residential demonstration district in western China.
Analysis of Secondary Pollution in Drinking Water Ultrafiltration System
Authors: Liu Hong Yuan , Fan Zhan Feng
Published: June 2012

Ultrafiltration processes are increasingly popular in drinking water treatment, as it can provide better quality water by removing microorganism and turbidity with lower filtration pore size, even without disinfection. Nonetheless, in our experiment the bacteria was occasionally detected in ultrafiltration effluent, and the related literature once had also been reported. This study was focused on the cause of secondary pollution in the drinking water ultrafiltration system, mainly from the production tank, biological stability, bacteria in air, as well as the membrane structure. And some solutions, including production water tank chlorination periodically, changing the operating mode of the ultrafiltration system, improving the design of the production tank, were studied to control secondary pollution in the treatment system.
Experiments of Separating and Featuring an Efficient SRB
Authors: Jiang Yan Li , Li Ai Hua , Di Jun Zhen , Niu Xiao Li , Zheng Jian , Li Qiang , Gu Hong Xue
Published: June 2012

By experiments, separate and purify efficient sulfate—reducing bacteria (SRB), which is identified as Desulfobacter. With its treatment of acid mine drainage(AMD) containing Fe2+ and Mn2+, obtain the optimum conditions that pH=6,temperature=37,vibrating intensity=100r/min, COD/SO42- =2.Under this condition ,the removal rate of SO42-、Fe2+ and Mn2+ is 88.16%、99.37% and 59.18% respectively with the initial concentration 1411mg/L for SO42-,257mg/L for Fe2+ and 325mg/L for Mn2+.This puts a theoretical foundation for the further study.
A Timely Multi-Point Simultaneous Manometry Used in Burst and Leakage Monitoring along the Water Transmission Pipeline
Authors: Lu Shao Ming , Li Fang , Li Shao Wen
Published: June 2012

On large-scale pipelines at a water supply capacity of 5-10 m3/s, the bursted flow can reach hundreds to thousands of cubic meters within a few minutes, which could trigger secondary disasters in the densely populated areas. But the accident is hard to be monitored and found, because the leakage flow is often only 1% to 5% of the water supply capacity. This paper presents the simultaneous manometry for the burst and leakage monitoring along the pipelines. The research found that it can alarm timely in 3min to 5min and provide key information such as detonation location and the amount of the explosion leakage. The method has been applied to Xijiang River Diversion Project in China and the water supply capacity is 3.5 million m3/d(40.5m3/s).
Research for Combined Drainage Networks in Chuanfang River Basin of Kunming City Based on SWMM
Authors: Zhu Xiao Min , Huang Bing , Wang Shu Dong , Zheng Jin Long , Yao Bo , Chen Su
Published: June 2012

A model for simulating combined drainage networks in Chuangfang river basin of Kunming City based on the Storm Water Management Model was established. The type and period of using water base on residential area, marketplace, school area, and guesthouse area Kunming city were introduced into the model, and their infection for drainage system was research. The results show that simulation results of two outlets flow have coherence with monitoring data based two typical rainfall in Kunming, the Nash-Sutcliffe efficiency coefficient is 0.71-0.82. And the model can be using analyze ‘bottleneck’ nodes and restricting conduits, simulating the running status of drainage network of combined drainage at raining and draining peak time of sewage water. The research provide strong technical support for rebuild drainage network in Kunming or other city.
A New Method to Estimate the Leakage Amount at the Water Supply Network Nodes in the Countryside Regions
Authors: Qiang Yue , Fan Zhe Chao , Zhao Ming Jie , Li Li
Published: June 2012

In order to investigate the leakage amount in the water supply networks in the countryside regions, a new method combined with GIS and DEM to estimate the leakage amount at water supply network nodes has been put forward. It is proposed according to the Chinese node leakage model, and it takes advantage of the strong spatial annalistic function of the GIS. The emphasis is put on the study of the topology relationship of the water supply networks which are built based on the GIS network analysis. And DEM model is used to calculate the elevation at the network nodes. And then the leakage amount of the water supply network nodes is estimated. Finally, specific examples have been verified in order to illustrate that the GIS-based method to estimate leakage amount at the water supply network nodes is efficient.
Reinforcement Effect Analysis of Dynamic Drainage Consolidation Based on Finn Constitutive Law
Authors: Yang Gui Hua , Yu Wei , Li Huai Qi
Published: June 2012

In coastal areas, soft soil treatment is the challenge which must be faced in process of engineering construction. Among numerous treatment methods, dynamic drainage consolidation method is a new and effective method. In this paper, The Finn constitutive law reflecting dynamic pore pressure has been applied to dynamic drainage consolidation analysis. The results show pore water pressure behaves a pulse response proces for the impact, vertical drainage systerm increase the effective drainage channels, speed up the drainage process.
Premixed Gas Flame Burning Velocities of Biomass Gasification Gas
Authors: Bai Bao Sheng , Zhang Ji Chun , Lin Bo
Published: June 2012

Discuss the flame burning velocities of biomass gasification gases and the methods of increasing them by calculating and programming through MATLAB. The results display that the flame burning velocities of biomass gasification gases are relatively low, and they increase when adding hydrogen, which has a higher flame burning speed. Satisfying effects are achieved under different equivalence ratios, initial temperatures and pressures. Research shows that flame burning velocities improve with the fraction of hydrogen volume increasing. It also suggests that with the rise of equivalence ratio, the velocities increase first, and then decrease, and they reach the highest when equivalence ratio is stoichiometric; an increase in initial temperature accelerates the burning velocities, while the velocities drop by enhancing the pressures.
Hydrodynamic Characteristic of Large Particles in Vibrated Fluidization Bed
Authors: Zhu Xue Jun , Jun Deng , Li Yu Feng
Published: June 2012

Hydrodynamic for 2D vibrated fluidized bed was studied with large particle glass beads of average diameters are less than 1.5mm.The effect of the vibration strength, the static bed height and the particle diameter on the critical fluidization velocity was analyzed. The results show that the critical fluidization velocity decreases with the increase of the vibration strength, and increases with increases of the static bed height and particle diameter. The effect of vibration on critical fluidization velocity was more significant than decrease the bed height and particle diameter. The empirical correlation equations to predict the critical fluidization velocity was established, and the results of the prediction were compared with the experimental data, the error is in range of ±10%. The results can provide important meaning on theory and instructing practice for developing the new drying technology with high drying efficiency and low dissipation of energy.
Exergy Analysis of the Vapor Compression Refrigeration
Authors: Ren Xiao Fen , Wang Jian Qiang , Li Xiu Yun , Jia Lian Dong
Published: June 2012

The paper builds up the model for exergy analysis of vapor compression refrigeration. According to the exergy analysis, it appears exergy loss degree of the main units in the system, and points out the way of reducing exergy loss and the approach utilizing energy rationally, and proceeds with exergy loss compare with aiming at that if condenser in surplus heat recycling. Conclusion is that adopting surplus heat recycling can reduce exergy loss. Furthermore, it analyzes exergy loss to a actual refrigeration aiming at temperature regulation, and provides the theory reference for improvement and optimization of the system.
Application of an Air-Air Energy Exchanger in a Building HVAC System in Xiamen
Authors: Li Li , Zhang Qing Ling , Li Ya Ping
Published: June 2012

An air-air energy exchanger (AAEE) has been introduced in the literature as a novel energy recovery system that transfers heat and moisture between the ventilation and exhaust air. In this paper, the application of an AAEE in a HVAC system is investigated. The paper discusses the dependency of AAEE performance on ventilation air and indoor and outdoor air conditions, it describes how to control the AAEE in different operating conditions (summer and winter). The suited meteorological conditions of the AAEE in buildings are given. Based on the humidity and temperature data of the typical meteorological year in Xiamen, the temperature distribution statistics throughout the year is studied and the air enthalpy difference is calculated. Combining with the demand of the indoor air conditioning parameters, the applicable hours of different types of AAEE, such as total heat and sensible heat, in Xiamen are analyzed. It is shown that the lower we intend to get the temperature and relative humidity, the more space there will be for the AAEE to work in summer. In winter, for the sensible heat AAEE, the higher indoor temperature we design, the more hours it works, the greater space we will have for heat recovery. But for the total heat AAEE, it will be used longer as the indoor temperature and relative humidity are designed higher. The study results show that the AAEE can be energy-saving and reduce indoor air pollution of modern buildings, improve indoor work and living environment. The result can provide basic principle and referenced data for product improvement and air-conditioning system design.
Performance Analysis of Solar-Assisted Refrigeration Cycle
Authors: Wang Lin , Duan Shuang Ping , Cui Xiao Long
Published: June 2012

Energy-conservation and environmental protection are keys to sustainable development of domestic economy. The solar-assisted cascade refrigeration cycle system is developed. The system consists of electricity-driven vapor compression refrigeration system and solar-driven vapor absorption refrigeration system. The vapor compression refrigeration system is connected in series with vapor absorption refrigeration system. Refrigerant and solution reservoirs are designed to store potential to keep the system operating continuously without sunlight. The results indicate that the system obtains pretty higher COP as compared with the conventional vapor compression refrigeration system. COP of the new-type vapor compression refrigeration system increases as sunlight becomes intense.
Investigation on Heat Pipe Application in Central Air-Conditioning Systems
Authors: Lv Jian , Yu Fang , Zhao Guo Min , Zhang Jun Mei , Yang Hong Xing
Published: June 2012

An experimental test has been conducted to determine the effect of heat pipe heat exchangers for pre-cooling and re-heating performance of central air-conditioning systems in Hung Hom Sport Centre. The objectives of this research project are to investigate the energy recovery efficiency from using the heat pipe heat exchangers in air conditioning system. The annual energy saving by using the heat pipe heat exchangers. The effect of energy recovery efficiency is significant.
Exploration on the Ventilation Design Strategies of Cave Dwelling Construction in Northern Part of Shaanxi Province
Authors: Zhu Yan Di , Xi Liao Liao , Zhang Lin
Published: June 2012

Cave dwelling is a traditional architectural form in the northern part of Shaanxi province. It is the product of local traditional culture and humanistic spirit, and corresponds with the requirements of energy-saving and sustainable development. This paper takes the traditional cave dwelling in the northern part of Shaanxi as the research object, and uses two kinds of methods: the analysis of the literature data and on-the-spot investigation to put forwards the traditional ventilation design strategies of cave dwelling construction in the northern part of Shaanxi province, which aims to explore the new methods of reforming traditional cave dwelling construction.
The Research on the Resistance Characteristic Coefficient in Heating System Based on the Improved Genetic Algorithm
Authors: Yang Xian Liang , Li Tong , Wang Song Lin , Wu Zheng Ren
Published: June 2012

With the development of the heating industry, the higher level of operation and management are required. Therefore it needs more accurate values of nodes pressure and flow. In this paper, based on the genetic algorithm, In order to realize the improved algorithm, change the rate of cross and mutation according to the fitness. After revising the resistance characteristic coefficient, we can get the more accurate values of nodes pressure. Finally, an example is given to verify the feasibility and validity of this method.
U-Tube Diameter Dependence of Heat Output for Borehole Heat Exchangers
Authors: Dai Chuan Shan , Wang Shuai , Qin Wei Xing
Published: June 2012

The heat output for borehole heat exchangers due to the variation of U-tube diameter was theoretically analyzed using the steady heat conduction model of a hollow cylinder. In the present model, except of the U-tube diameter, the other influencing factors on the heat output, such as the heat transfer coefficient inside U-tube, tube thickness and thermal conductivity, have been taken into account.
Reburning Characteristics Research of Combustible Gas in CFB
Authors: Jiang Da Long , Wang Tao , Hu Xiao Ying , Zhang Han Fei , Liu Ji Zhen , Yang Yong Ping
Published: June 2012

Experimental research on the characteristics of co-combustion coal and combustible gas has been carried out. The influence of nozzle position and combustible gas reburning ratio on N2O and NO removal rate were carried out at CFB experimental platform. It is found that N2O removal rate achieved a maximum value when the reburning gas was injected into furnace from nozzle C with a height-diameter ratio of 8.3, and the NO removal rate is about 50%; When the combustible gas were injected into furnace from nozzle C, the N2O removal rate kept increasing with the increase of reburning ratio (Rm), which can reach 99% when the Rm value is 10.5%. In addition, the NO removal rate is increasd after the first reduction with the increase of Rm, when the rate is about 39% with Rm is 10.5%.
The Study of the Evaporative Condensation Heat Processing Schema Based on Utilization of the Exhaust Air
Authors: Wang Rui Hai , Wang Li Jun , Wang Yu , Li Wei Hua , Sui Lu Yan , Li Yong , Wang Bo , Jiang Feng , Xu Xing Bin
Published: June 2012

In order to solve the ‘condensation heat excess’ problem for protective underground engineering, a new condensation heat processing schema was proposed, which is based on the theoretical analysis results that the condensation heat should be transferred to the exotic environment. The main idea of the proposal is utilizing exhaust air of the ventilation system and applying evaporative heat transferring mode.