bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental Research of a Steel Frame with Cantilever Beam Spliced Joints under Surface Deformation
Authors: Xia Jun Wu , Liu Xiao Wei , Wen Fa Ming , Xiong Jun Hui
Published: May 2011

Structural additional force and deformation of a single-level, single span steel frame with cantilever beam spliced joints under the horizontal deformation and vertical deformation were researched by a physical simulation experiment. The results showed that the horizontal tensile-compression deformation is the most unfavorable to the frame. However, the frame was still in elastic stage and can resume normal work status after unloading, which make it a good anti-deformation performance.
Analysis on Backwater Calculation of Ice Jam during Ice-Flood Period
Authors: Shi Jie , Zhang Xiao Lei , Zhang Feng Ran
Published: May 2011

The river ice is a commonly natural phenomenon in the cold region. And serious ice situation can cause the ice-flood disaster. So the impact assessment on ice situation is an important factor which need considering in development and utilization of water resources. Based on the backwater calculation of ice jam in ice-flood period, and take the reach near Dazhunzeng Second-line Yellow River Railway Bridge for example, the backwater calculations of ice jam are carried on for the conditions before and after the construction of Dazhunzeng Second-line Yellow River Railway Bridge, and the conclsions are drawn that: (1) the construction of Dazhunzeng Second-line Yellow River Railway Bridge has less influence on the ice-flood control during freezing period; (2) after the construction of Dazhunzeng Second-line Yellow River Railway Bridge, during river-ice breakup the bridge section is combined affected by the old and new bridge, as a result the backwater height before the ice dam of bridge section is about 7.59m, and the ice surface elevation of the bridge section is up to 981.80m; (3) According to the current operation mode of Wanjiazhai Reservoir, the construction of Dazhunzeng Second-line Yellow River Railway Bridge will not have bad impact on the operation of Wanjiazhai Reservoir.
SSOR-PCG Method for Real Time Temperature Simulation on Caohe River Aqueduct in South to North Water Transfer Project during Construction Period
Authors: Zhang Ping , Tian Bin , Zhang Bo
Published: May 2011

The temperature stress due to temperature changes is often more than the concrete tensile strength during construction period and operation period in massive concrete structures in hydraulic engineering, so the analysis of temperature stress, temperature control and measures to prevent the cracks become very important. The solution of large sparse linear equations is essential to finite element simulation in simulation analysis of temperature field. However, the traditional direct method will cost too much memory and calculation time, and the nodes is limited. The symmetric successive over relaxation (SSOR)-preconditioned conjugate gradient (PCG) method is a very efficient iterative method for solving large sparse linear equations. Construction process simulation and temperature filed calculation during construction period about Caohe river landing rectangle aqueduct of Beijing-Shijiazhuang emergency water supply engineering of middle-route of south-to-north water transfer project are carried out by FEM code using SSOR-PCG method, then the calculation result and monitoring value are compared. The comparison result shows that temperature field during construction can be accurately simulated by simulation calculation, which is helpful for guiding construction and choosing construction scheme, and worthy to popularize to other similar projects.
Slope Safety of Earth Rockfill Cofferdam with Nonlinear Shear Strength
Authors: Lu Xiao Chun , Tian Bin , Qin Yan Fu
Published: May 2011

Based on numerical simulation of the seepage field of earth rockfill cofferdam using nonlinear Finite Element Method under the action of flood during construction period, the stability of the cofferdam slope with nonlinear shear strength is studied. The effectiveness and applicability of the method introduced in the paper is certified through computation in the study on the practical project. The paper provides an effective analysis method for the study on the stability of dam slope of earth rockfill cofferdam.
Analysis of High Concrete Arch Dam Thermal-Creep-Stress
Authors: Zheng Ke Hong , Zheng Bing Yin
Published: May 2011

The calculation of thermal stress is important to high concrete arch dam. In the progress of construction simulation analysis, the distribution of thermal stresses should be paid attention for it has great influence to arch design and rapid construction. The impacts on thermal stress are water temperature and air temperature and so on. In this paper, the author also thought about of the influence of creep, and applied the formulations of predecessors to finite element program. A engineering example about some high arch dam proves correctness and feasibility of considering thermal-creep –stress.
The Compressive Behavior of Horizontally Casted Concrete Filled Steel Tubular Members with Consideration of the Process of Concrete Casting
Authors: Sun Wen Bo , Luo Yi Qun , Huang Wei
Published: May 2011

Concrete casting effect and the hooping effect of concrete filled tubular members is considered in the study of this paper. Firstly, standard stress-strain relationship of concrete and steel is chosen to simulate others’ test, and meanwhile the calculation results by nonlinear finite element analysis are compared with the results of the test. Then the bearing capacity of horizontally casted concrete filled steel tubular members under axial compression is contrasted among different construction processes. Finally, the effect of slenderness ratio of concrete filled tubular members is studied so as to reveal the relationship between the bearing capacity and slenderness ratio.
Seepage Field Study of Xiaowan Hydropower Project
Authors: Wang Yong Xiang , Xu Qing , He Ji , Chen Sheng Hong
Published: May 2011

The Xiaowan Hydropower Project is located in the middle and lower reaches of the Lancang River in Yunnan Province, China. The arch dam of this project, with a height of 294.5m, is by far the highest dam of its type that has been completed in the world. The great water potential makes it necessary to assess the seepage behavior in the dam-foundation system. Due to the complexity of geological conditions and seepage control system, the research is full of challenges. In this paper, the ﬁnite element method (FEM) is adopted to simulate the three-dimensional seepage field. The initial flow method and the boundary pre-adjustment method are combined to obtain the seepage free surface and overflow surface under complicated boundary conditions. The hydraulic potential contours, seepage gradient, drainage discharges, and so on, are all analysed and the results show that the seepage control system is reasonable and effective. Furthermore, the results of the seepage field can provide suitable seepage load in the stress-strain and stability analysis for the dam-foundation system of Xianwan. At present, the project is in good operation.
Study on Integrated Approaches of Water Resources Allocation in Tianjin
Authors: Peng Jing , Qi Lan , Wang Ren Chao
Published: May 2011

This study investigated the characteristics of various water resources in Tianjin, explored the needs for the study of water resources allocation, and identified the current issues of water resources allocation in Tianjin. The water resources allocation framework was established by adopting the cultural algorithm approach. A case study was done for Tianjin by utilizing this framework to evaluate the water resources allocation in 2008. It shows that the integrated approach of water resources allocation can effectively relieve the water shortage pressure of Tianjin, maximize the benefits for the limited water resources. This study provides a theoretical guidance for the water resources allocation in this area.
Investigation on Mechanical Behavior of Hydrological Tower
Authors: Xiong Hui , Li Zheng Liang , Deng Nuan
Published: May 2011

The safety and reliability of hydrological tower play an important role in the security and accuracy of the hydrological measurement. In order to simulate the space mechanical characteristics of the composite structure of tower with guy lines accurately, the finite element program is used to establish a precise three dimensional space finite element model. The structural strength and stability was also analyzed. Meanwhile, the static performance and vibration characteristics of the tower with guy lines was compared with the ones of the tower with none guy lines. The results show that the mechanical characteristics of composite structure are similar to the ones of continuous beams with lateral bearing spring. The guy lines rationalize the force distribution on structures, enhance the structural bearing capacity, and increase the structural stiffness. In addition, the paper can be a reference for the analysis of hydrological towers in aspects of numerical analysis, design methods and data.
Limit Equilibrium Analysis of Sliding Block Stability under Earthquake
Authors: Liu Yao Ru , Li Bo , Leng Kuang Dai , Huang Yue Qun
Published: May 2011

Time history analysis is performed on geotechnical engineering structures under earthquake actions using 3D nonlinear FEM. The distribution of internal force on slide surfaces has been interpolated from the stress field of FEM with 3D Multi-grid Method. The safety factor with time history of sliding block can be obtained by limit equilibrium analysis and its dynamic stability can be evaluated. For blocks sliced by single slide surface and wedge-shaped double slide surfaces, general formulas of safety factor are given and their applicability have been analyzed. Analysis and evaluation of slide block aseismic stability are performed on high slope on the right bank of Dagangshan arch dam.
Numerical Simulation of the Foundation of Wind Turbines about Different Reinforcement Types
Authors: Xu Xin Yong , Wang Jian Wei , Jiang Li , Liu Xian Liang , Zhang Di
Published: May 2011

The three-dimensional finite element numerical model of wind power generator unit is created by using ANSYS. The elastic-plastic constitutive is introduced and the nonlinear contact is set up between the foundation stub and concrete. The different reinforcement arrangement’s impact on structure is researched, the strength characteristic and law of reinforcement concrete is discussed and a more rational scheme is raised. It’s more rational to consider the contact status and material nonlinearity. The research results offer scientific basis for design and optimization on foundations of wind turbines.
Analysis of Bulb Turbine Hydropower Station Plant with 3D Finite Element Method
Authors: Fu Jian , Tang Ke Dong , Wen Xin Li , Guo Xue Mang , Zhao Ji Wei
Published: May 2011

The overall structure of a hydropower plant with bulb tubular units is calculated and analysed in 6 kinds of load cases, and the maximum stresses in different directions and the positions where the maximum stresses appear in the hydropower plant structure. The conclusions show that the plant is safe and the design is reasonable.
3D Seismic Dynamical Response Time Interval Analysis of Different Segment Length of Wharfs
Authors: Shen Cai Hua , Chen Xiao Feng , Niu Xing Wei
Published: May 2011

Considering the effect of the actual landform and the pile-soil dynamical interaction, this paper uses the dynamic time interval analysis to analyze the response of horizontal seismic load of different segment lengths of high-piled wharfs. It makes research on the relative displacement, the acceleration, the maximum stress and the shear stress of the wharf construction and the variation of the shear force, the bending moment and the torque of the pile in the action of acceleration in true earthquake records. It determines the reasonable subdivision length of high-piled wharf in actual coast. Calculations show that, the wharf torsion caused by the asymmetry of terminal structure and pile, and the uneven stratum facilitates the response, and increases the shear stress of the pile. The placement of piles and the uneven stratum are the main factors of the internal force of terminal structure in action of earthquake, The optimal design of partial reinforcement should be adopted due to the considerable shear stress on the bezel panel. This method can provide reference to the design of the terminal structure in deep sea as well.
Evaluating the Wetting Induced Deformation of Rockfill Dams Using a Hypoplastic Constitutive Model
Authors: Fu Zhong Zhi , Liu Si Hong , Gu Wei Xing
Published: May 2011

Evaluating the wetting induced deformation of the shell is one of the most important issues in designing a high rockfill dam. Excessive wetting deformation and the relevant stress deterioration in adjacent impervious structures may cumber the normal operation of the engineering and seriously risk the safety of the dam. In this paper, a hypoplastic creep model is incorporated into a finite element procedure to study the wetting induced deformation of a rockfill dam. Considerable lateral movement towards the upstream and an additional wetting collapse presented in the upstream shell induced by reservoir impounding is effectively predicted by the finite element model. The reasonable results confirm the feasibility of applying the hypoplastic model to the evaluation of the wetting induced deformation in dam engineering.
Research on the Numerical Simulation of Zoning Flood Retarding and Sand Silting of Flood Plain in the Lower Yellow River
Authors: Zhang Xiao Lei , Sun Dong Po , Li Jun Jie
Published: May 2011

The 2-D water and sediment mathematical model which reflects flood retarding and sand silting of flood plain in the Lower Yellow River has been set up in this paper. Through carrying on 2-D water and sediment numerical simulation of the “96.8” typical flood, the authors studied influence of zoning flood retarding and sand silting on flood travel, flow structure of floodplain-channel and transver exchange of water and sediment. The simulating results in different conditions show that, adopting the zoning flood retarding and sand silting in the Lower Yellow River effectively worked on retarding flood and sharpening peaks in the flood retarding basin, guaranteed and expanded transver exchange of water and sediment in the floodplain and channel and maintained the river channel’s vigor. This can relieve “secondary suspended river” states in the Low Yellow River to a certain extent.
Back-Analysis of Indoor Test Parameters for Rock-Fill of Shui Bu Ya CFRD
Authors: He Lei Ming , Du Li Hui , Yang Jian
Published: May 2011

In the numerical calculation of geotechnical project, it’s difficult to confirm the parameters because of the complexity and the uncertainty of them as the time is changing. However, the back-analysis provides us an effective way. Based on the result of the triaxial test on rock-fill of Shui Bu Ya CFRD, the thesis adopts the direct back-analysis method which combines the BP Neural Network and Genetic Algorithm to calculate the Tsinghua non-linear K-G model parameters of the rock-fill. The back-analysis parameters are used to simulate the filling process of Shui Bu Ya CFRD and predict the displacement of the dam. The thesis provides a technical reference for displacement back-analysis of soil parameters for CFRD.
Influence of Supports and Water Depths on Dynamic Characteristics of Aqueduct Structure
Authors: Bai Xin Li , Su Hai Li , Pan Qian
Published: May 2011

In this paper, dynamic characteristics analysis is carried out for a large aqueduct of South-to-North Water Transfer Project using large finite element analysis software. Two kinds of connection supports are considered, namely elastic support and completely simple support. Six kinds of water depths are calculated by additional mass method: empty aqueduct, 1/4 water depth, 1/2 water depth, 3/4 water depth, designed water depth, full water depth. Results show that basin type rubber support strengthens the constraint to aqueduct, and strengthens the connection of aqueduct to pier, and also increases the system stiffness, therefore the natural frequency is higher than that of completely simple support; The influence of water to dynamic characteristics of the aqueduct is quite obvious, so water effect must be considered in computation; Water has no influence on the principal mode shapes of the aqueduct structure, i.e. the dry mode shape and the wet mode shape are similar in appearance.
Galerkin Solutions of the Simply-Supported Steel and Concrete Composite Girder in Considering Relative Slips and Shear Lags
Authors: Chen Yu Ji , Luo Qi Zhi
Published: May 2011

By mean of potential energy various principles,the governing differential equations of the steel and concrete composite girder in considering relative slips between steel girders and concrete slabs and shear lag effects of the flanges and the concrete slab are derived. The equations are solved by Galerkin method. It is shown from the calculating example that the proposed method not only is easy to calculate, but also has high convergent speed
Fiber Reinforced Hydraulic Concrete Using Four Gradations of Aggregates
Authors: Li Ke Liang , Yang Zhong Zheng , Nie Wei Ping
Published: May 2011

Controlling crack of hyperbolic arch dam with a height of 305 m in Jinping hydropower station is an important problem. To improve the anti-cracking ability and reduce cracking risk of hydraulic concrete, polyvinyl alcohol (PVA) fiber and polypropylene thick fiber were used in hydraulic concrete using four gradations of aggregates. Indoor and productive tests were carried through to comparatively analyze workability, physical and mechanical properties and anti-cracking ability. Workability of fiber reinforced concrete was improved to be in favor of construction. When two kinds of fiber were used in concrete, the anti-cracking ability was greatly enhanced with lower elastic modulus-to-strength ratio and lager ultimate tensile strain. Concrete using PVA fiber had better anti-cracking ability than that of concrete using polypropylene thick fiber. PVA fiber reinforced concrete was applied in Jinping hydropower station. It is proved that PVA fiber reinforced concrete has good properties reaching design requirements of workability, compressive strength, ultimate tensile strain, frost resistance, permeability resistance.
Seismic Acceleration Distribution Analysis of High Earth-Rock Dams in Three-Dimensional Space
Authors: Zhang Rui , Chi Shi Chun , Lin Gao
Published: May 2011

When pseudostatic method is employed to analyze slope seismic stability of high earth- rock dams, earthquake load is computed according to dynamic seismic coefficient figure in the present Specifications for Seismic Design of Hydraulic Structures (DL5073-1997). The figure is only suitable for earth-rock dams lower than 150m. While at the present time, many earth-rock dams to be constructed are higher than 150m. Compared with low dams, high order self-vibrating period of high dams is easy to coincide with seismic predominant period, and high order vibrations are constantly to be activated and amplified, which result in seismic acceleration distribution is different from low dams. With analytical and finite element method respectively, seismic acceleration distribution of high earth-rock dams is analyzed. Suggested dynamic seismic coefficient figure of earth-rock dams 300m-level in height is put forward, which offer a supplement for the present Code for Seismic Design of Hydraulic Structure.
The Differential Evolution and its Application in Short-Term Scheduling of Hydro Unit
Authors: Deng Hai Ying , Zhang Zhi Gang , Yu Yi Gang
Published: May 2011

Differential evolution algorithm (differential evolution, DE) is a multi-objective evolutionary algorithm based on groups, which instructs optimization search by swarm intelligence produced by co-operation and competition among individuals within groups. While it can track the dynamics of the current search by the DE specific memory, in order to adjust their search strategy. The strong global convergence and robustness of the characteristics can solve the complex optimization problem which it hardly solves with the mathematical programming methods. This paper presents it to the research of short-term scheduling of hydro plant. Accord to the application of the hydro unit, the results shows that reasonable and effective.
Durability Study and Service-Life Prediction of Hydro Structures Concrete Members
Authors: Zhao Yuan Dong , Li Geng , Ma Yan
Published: May 2011

The failure process of hydrostructures concrete is a stochastic process relating to time and space. The durability failure mechanism, durability failure type and durability failure mode were presented. The relation of durability and resisting ability was studied. Based on credibility theory, the method for predicting service-life of hydrostructure concrete was put forward. Through a typical case analysis, the mend measures to improve durability were introduced. The design method for hydrostructure concrete should be controlled by both stress state and durability instead of traditional one.
Influence of Thickness of Cushion Layer on Spiral Case Stress
Authors: Lu Shan Shan , Liu Xiao Qing , Zhao Lan Hao , Sun Peng
Published: May 2011

Spiral case with cushion layer is commonly given a significant consideration on hydroelectric power station design for vital practical reasons. In this paper, combined with an engineering project, non-linear constitutive equation suited to concrete material was selected according to the finite element theory. On the condition of structure weight and pressure of internal water, the combinations composed of jointly loaded spiral case structure including steel lining, different thickness of cushion layer and reinforce concrete structure around spiral case are calculated and analyzed. The relation between stress (concrete stress & spiral case stress) and thickness of cushion layer is proposed, which in turn provides design basis for the project.
Slope Instability Assessment Based on 3D Slope Model and Numerical Simulation Analysis
Authors: Li Ming Chao , Liu Fei
Published: May 2011

Based on an actual slope in the Three Gorges reservoir, the 3D geological model was built as the foundation. The numerical simulation method of the slope instability process was put forward. Then, a series of dynamic parameters were computed, including stability factors, accelerations, velocities, displacements. And the hazards of surge and river-blocking were analyzed. It offers a new analytical approach to the reservoir slope instability.
Effect of Erosion Damage on Diffusion of Sulfate Ions in Concrete
Authors: Sun Chao , Chen Jian Kang
Published: May 2011

Based on Fick’s second law and the damage evolution due to sulfate attack, a new model is proposed to analyze the diffusion of sulfate ions in concrete. The relation between erosion damage and erosion time, as well as the concentration of sulfate ions is firstly investigated by virtue of the ultrasonic experimental results. Furthermore, the damage evolution is treated as the increase of porosity, and a new nonlinear differential equation on the diffusion of sulfate ions is established by substituting such an increasing porosity into Fick’s law. The nonlinear diffusion equation is then solved by numerical method. It is found that the erosion damage can significantly affect the diffusion of sulfate ions in concrete.
Numerical Study on Effects of Change of Water Depth on Water Exchange Ability of Nearly Closed Bay
Authors: Zhang Rui Jin , Zhang Hong Zhan , Jiang Qian
Published: May 2011

The water exchange with outer sea for the nearly closed bay is very weak, leading to the serious deterioration of the environment of the bay. Numerical experiments have been performed to find the effects of change of the water depth at the bay mouth on the water exchanging ability of the nearly closed bay. The results indicated, by decreasing the depth at the nearly closed bay mouth appropriately, the water exchanging ability can be improved.
Clustering Analysis of Hydrologic Type in Coastal Zone
Authors: Gao Mao Sheng
Published: May 2011

By the analyzing of Q cluster and characteristic factor matrix, coastal hydrological types and their distributions are found by selecting 7 characteristic factors in 26 districts of the China coastal zone. In the view of environmental hydrology and marine engineering, the distribution types of coastal zone are mainly divided into sedimentary coast (including sandy coast, muddy coast, strongly hydrodynamic coast) and rocky coast (including massive bedrock coast, grit bedrock coast, bank slope and platform coast). The formation, development and evolution of the coastal zone are mainly controlled by the land geologic actions, particularly by tectonism and hydraulic condition, and the ocean geologic actions only take part in the modification of the coastal features. The topography and lithology are mainly controlled by distribution of land water flow in coastal zone.
Bearing Capacity of Suction Caisson for Offshore Floating Wind Turbine
Authors: Gong Xiu Bin , Fan Qing Lai , Wu Ke
Published: May 2011

Presented in this paper are the three-dimensional nonlinear finite element analyses of the failure envelopes of suction caisson under torsion, vertical and lateral pullout combined load in soft clay. The soft clay under undrained condition is simulated by perfectly elasto-plastic Tresca model. Through the numerical analyses, the failure envelopes for combined loading (V-T、H-T、V-H-T) of suction caisson is reviewed. And the mathematical expression of failure envelope is deduced. It is shown that (1) the circular plastic failure area is outward-extending. (2) The bearing capacity of suction caisson foundation in V-T、H-T load spaces is increasing with the aspect ratio L/D. (3) The equation of failure envelope can be used to evaluate the stability of suction caisson foundation for offshore floating wind turbine.
The Crashworthiness Properties of Rectangular Column Steel Sandwich Protection Devices for the Bridges
Authors: Mi Xu Feng , Li Dong Qin
Published: May 2011

In the paper, the protective equipments of the bridges were studied. The new type of protective devices, which was the rectangular column sandwich plate protective devices, and they were suggested. The ANSYS/LS-DYNA, which is non-linear dynamics finite element software, was applied to simulate the crashworthiness performance of the rectangular column steel sandwich plate, and analyzed the crashworthiness performance factors of the sandwich plate from the different structure parameters to optimize the overall crashworthiness sandwich plate. After structural optimization, it can be gotten that the rectangular column sandwich plates were better than traditional steel plates in crashworthiness performance. Then, the sandwich plate was used to replace the outside steel plates of the traditional box-protective device, from that obtained the overall crashworthiness performance of the rectangular column steel sandwich protective devices were better than the traditional box-protective device.
Experimental Research on the Influences of Wave Height on Towing of 4-Bucket Foundation Platform
Authors: Le Cong Huan , Ding Hong Yan , Dong Guo Hai , Zhang Pu Yang
Published: May 2011

Internal air pressure and water pressure of the buckets foundation, acceleration and dragging force of the 4-bucket foundation platform were determined to analyze the influences of wave height on towing when 4-Bucket foundation platform is towing in conditions of a certain towing velocity, mooring point position and draught in different regular waves based on the model test. Comparing platform towing in following and head waves, the heave motion of the latter is more strenuous than that of the former; the stability and seakeeping of the former is better than those of the latter. Roll motion, pitch motion and heave motion appear aggravate phenomenon with the increase of wave height.
Model Test Study on Added Mass Coefficient of Four Buckets Foundation Ocean Platform
Authors: Ding Hong Yan , Liu Xian Qing , Diao Jing Hua , Zhang Pu Yang
Published: May 2011

In this paper, the internal air pressure and bottom water pressure of the buckets, the acceleration of swaying, surging and heaving of platform were determined by the sensors fixed on the platform, as a naval bucket foundation platform for example. The motion rules of heave and sway of bucket foundations are studied with different drafts. The results of this test showed that the added mass coefficient of heave, roll and pitch are declined with the increase of the draft; the natural frequency of heave is constant with different drafts but the roll frequency and pitch frequency are consistent with the changes of the draft; the frequency of heave is larger than that of roll and pitch but the added mass coefficient of heave is lesser than that of roll and pitch.
Study on the Fuzziness in Fatigue Life Estimation of the Foundation of Offshore Wind Turbine
Authors: Li Wei
Published: May 2011

Ignoring the influence of the load sequence and the damage caused under low-stress level are two mail shortcomings of traditional fatigue life estimation method based on the Miner theory. Fuzzy method for fatigue analysis of the foundation of offshore wind turbine is investigated. A fuzzy accumulative damage model is founded and used for fatigue life analysis of a tripod foundation. The fatigue damage is calculated using the traditional certainty method and the present fuzzy method. A tripod foundation under single-level and multi-level fatigue loads is used as the test structure. And the load sequence is considered. The calculation results of stress level are used with three forms, named the increasing mode, the to-and-fro mode and the sine mode, for structure fatigue life analysis. It reveals that the load sequence and low-stress level play an important part in the fatigue analysis and should not be ignored. The anti-fatigue character of the structure under a group of increasing loads is better than the structure under a group of decreasing loads; and it is called the forging effect. The present fuzzy accumulative damage model is more accurate and reasonable than the traditional certainty method.
Measuring Expansion Method on Sulfate Resistance Properties of Hardened Cement Paste
Authors: Li Xiu Juan , Zhang Jian
Published: May 2011

Mechanism of sulfate attack is a very complicated process. In the laboratory, there are a variety of testing methods for cement resistance to sulfate attack. But there are still some problems. For example, the method often used in the United States Association standards and testing (ASTM) does indicate that expansion happens in the event of specimens’ breakage, but not point clearly the minimum amount of expansion leading to the strength damaged. In the present study, the method of measuring expansion of hardened cement paste sulfate resistance is discussed. It is found that experimental measurements can be used to study the erosion of sodium sulfate solution, but not be used to evaluate the anti-corrosion properties of hardened cement paste to magnesium sulfate.
Application of Automatic Energy Conservation Technology to Hot Water Supply System
Authors: Lu Chu Huan , Zhao Bao Shan
Published: May 2011

In order to realize the automatic energy saving control for centralized hot water supplying system, this paper puts forward a frequency conversion adjusting speed automatic supplement water system with frequency converter used as driving unit pump. It can provide constant supplying hot water pressure by timely adjusting supplement water quantity according to the change of water consumption. The hot water temperature control system was designed to maintain the temperature constant through throttle governing steam quantity. Through the practical run, the whole system works steady, which has remarkable energy-saving effect and high automatic degree.
The Project Design of Seasonal Reclaimed Water Utilization System for Liaobin Water Town
Authors: Zhang Ji Ku , Jiang Yang , Zou Lin
Published: May 2011

Conbined with the Eco-residential Island, the project of reclaimed water utilization for Liaobin water town in Panjin is mainly introduced. The reclaimed water resource contains rainwater and domestic sewage water, which is collected mainly in the range of urban (regional).After the second-level processing by sewage treatment plant, it is mainly served as flushing water ,which is called “full-sewage” reuse system; in dry season, it is reused directly after corresponding treatment; and in rainy season, the excessive water is pumpinged into the surrounding waterbodies. The research analysis indicates that the plan of “full-sewage” reuse system and the seasonal reclaimed water utilization system used in this area are reasonable and feasible, which can make full use of the reclaimed water and save the water resources effectively, meeting the demand of sustainable development .
The Beneficial Cycle of Urban Water Use in Nanchang
Authors: Zhan Jian , Huang Xiao Hua , Zhou Ze Lin , Chen Zhan Li
Published: May 2011

Based on the theory of sustainable regional water resources, the basis theory of comprehensive evaluation about the beneficial cycle of urban water use was constructed and the evaluation index system about the beneficial cycle of urban water use was established. Using the improved AHP to comprehensive assessment water using conditions of Nanchang City, the evaluation result is middle. So we must analyze the reasons and the main factors of the evaluation results for better water utilization in Nanchang City.
Study on Water Qualities Change along ECOSUNIDE Process
Authors: Zhang Yan Qiu , Li Ang , Li Yan
Published: May 2011

By distributing influent to different action zones, a high sludge concentration and high sludge concentration gradient were carried out in ECOSUNIDE treatment system. Carbon source was respectively supplied to anaerobic and anoxic tanks, meeting the demand of PAOs for phosphorus release and denirifiers for denitrification. The operation mode of muliple A/O (anoxic/oxic) was employed to avoid the inhibition of nitrate on nitrification and phosphorus accumulation, improving the nutrient removal efficiency without internal reflux. In the paper, the experiments were performed on ECOSUNIDE to investigate the change law of water qualities in the whole system by monitoring MLSS and every index including CODCr, ammonia nitrogen, total nitrogen and total phosphorous, etc. From the results, the removal rates of CODCr, ammonia nitrogen, total nitrogen and total phosphorous were 87.28%, 96.99%, 77.97% and 79.92% reseparately and there was a consistency of the removal rule for every kind of pollutant in the system.
Treatment of Micro-Polluted Surface Water by the Nanomaterials Modified PVDF Ultrafiltration Membrane
Authors: Zhan Jian , Mei Na , Chen Zhan Li , Huang Xiao Hua
Published: May 2011

The PVDF ultrafiltration membrane was modified by step in situ polymerization coupled with TiO2-PANI membrane surface modifying. It has been prepared by different oxidants, such as ammonium persulfate (APS) and ferric chloride (FeCl3). Meanwhile, application of the modified PVDF ultrafiltration membrane on treating micro-polluted surface water was studied. Turbidity removal efficiency, organic compounds and ammonia nitrogen (NH3-N) were mainly concerned. The results show that the modified PVDF UF membranes can remove 95% turbidity, UV254higher than 50% which was increased greater than the original film. When FeCl3was taken as oxidant with 0.03mol/L, less by-product, NH4+, was generated than APS. Thus, the ammonia nitrogen removal rate is as high as 85.2% and is 20% more than the original film.
Simplified Computation of Elastic-Plastic Displacement Response of High-Rise Steel Structure under Earthquake Considering Torsional Effect
Authors: Zhuang Jin Zhao , Ju Jin San , Jiang Xiu Gen , Feng Xiao Mei , Yuan Jun
Published: May 2011

Considering unavoidability of torsional vibration of high-rise buildings during earthquake, for a simpler and more accurate way to compute the maximum interstory drifts, through establishment of different structure calculation model. Structure analysis program CANNY 3D was used to conduct 3D and 2D time-history analyses on irregular steel structure models under frequently occurred small earthquakes and large earthquakes. Finally, by comparing maximum interstory drifts between each floor, a method was presented to simplify 3D computation of elastic-plastic interstory displacement of high-rise irregular steel structure into a computation plane 2D structure.
Fractal Dimension of Floc Growth in Micro-Coagulation Stage I: Using to Forecast Water Quality of Settled Water
Authors: Nan Jun , Li Hao Yu , He Wei Peng
Published: May 2011

The coagulation experiments, with Kaolin as objects, aluminum chloride (PAC) as coagulant, were accomplished under different conditions. In the experiment, the particle size distribution and turbidity in water were detected by on-line detector. Result showed that all floc changed in speed in the first 5 min of the coagulation process and the fractal dimension of floc growth in the first 4 min of coagulation process had best linear relation (R2 was biggest and more than 0.92 )with turbidity, total particle number and the number of particle size <5µm of settled water. The fractal dimension had a direct ratio relation with water quality of settled water and could be used as a factor to forecast water quality of settled water.
Water Distribution System Modeling and Smart Grid Technology
Authors: Shu Shi Hu
Published: May 2011

In order to study how information and technology can be used to improve water management, smart grid technologies were introduced into the water industry. This paper describes a project to integrate GIS, SCADA and online hydraulic model to assist water engineers in assessing the water distribution system. The integrated system simulates the flow and concentration of chemical contaminants online in municipality's water distribution system. The integrated system is a powerful tool for routine planning and emergency response and also for remote leakage detection and prediction of pipe burst. The capabilities of the integrated system can greatly assist in the decision making processes for network asset inventory, rehabilitation requirements, and financial planning.
Analysis on Mass Balance and Optimization of Operating Performance in Anaerobic-Anoxic-Aerobic Oxidation Ditch Process
Authors: Zhang Zhi , Li Bo Lin , Zhang Chi , Chai Hua
Published: May 2011

The equations of COD, nitrogen and phosphate mass balance is established and the results show that the COD, nitrogen and phosphorus balance ratios are 98.3%, 73.1%, 98.4%. COD removal is achieved by the discharge of aerobic oxidation and excess sludge, accounting for 86.3% of the total. The loss of nitrogen balance is due to the existing of SND. Nitrogen removal is mainly achieved by the discharge of denitrification process, including anoxic denitrification process (33.6%) and SND process (23.3%). In order to solve the problem of large energy consumption, some optimized control measures are proposed and the test results indicate that TN removal rate has increased from 89.2% to 93.1%, tons of water at power consumption has dropped from 0.35 to 0.26kW•h/m3.
Preozonation on Removal of Organic Matter in Water and Biological Stability
Authors: Zhang Hong Zhuan , Gao Nai Yun , Zhang Yong Ming , Yu Li Zhi
Published: May 2011

The pollution of drinking water source has become a serious problem facing the world, and it is even more severe in China undergoing rapid development. Statistics show that the total annual emissions in China is 35.3 billion m3, CODMnis about 760 million tons, the treatment rate is only 23.6%, a lot of waste water without being treated in many small towns was discharged directly . It polluted seriously the water supply in many cities and industrial and mining water. According to the survey, among China's seven major river systems, 110 Key Sections, 68% of Water Quality is Ⅲ, Ⅳ, Ⅴ Grade. 90% of the national urban water has been polluted, the most prominent problem is the organic pollution. There are low dissolved oxygen, and the density of ammonia nitrogen, COD, BOD, and TOC in the water is high. Some of the polluted water bodies often appear black smelly serious situation. These organic polluted drinking water source, due to the presence of a large number of organic ozone-depleting substances , by conventional coagulation, sedimentation, filtration and disinfection treatment process, is difficult to achieve the requirements of the national mandatory Standard— "drinking water health standards"(GB 5749-2006) , issued and revised by the national standards committee and Ministry of Health, which there is a new comprehensive index of organic matter - the oxygen consumption is to control trace organic matter in water.
Numerical Simulation on Mechanical Ventilation for Odor Removal Efficiency in a Bathroom
Authors: Fuh Yiin Kuen , Huang Wei Chi
Published: May 2011

This paper numerically studies the effect of ventilation rates and bathroom equipment locations on the odor removal efficiency in a modeled bathroom. Simulation results agree well with previously published experiments such that moving exhaust air vent from ceiling to wall and addition of one supply fan would significantly improve odor removal efficiency. In addition, by doubling the area of exhaust vent under a fixed air change rate, odor removal efficiency (ORE) can be greatly enhanced to 16-30% while previous experiment showed only a moderate 4% increase in ORE when doubled the flow rate of supply air.
Design Range of Indoor Relative Humidity in Radiant Cooling Environment
Authors: Sui Xue Min , Zhang Xu , Han Guang Hui
Published: May 2011

Relative humidity is an important micro-climate parameter in radiant cooling environment. Based on the human thermal comfort model, this paper studied the effect on PMV index of relative humidity, and studied the relationship of low mean radiant temperature and relative humidity, drew the appropriate design range of indoor relative humidity for radiant cooling systems.The results show that high relative humidity can compensate for the impact on thermal comfort of low mean radiant temperature, on the premise of achieving the same thermal comfort requirements. However, because of the limited compensation range of relative humidity, together with the constraints for it due to anti-condensation of radiant terminal devices, the design range of relative humidity should not be improved, and it can still use the traditional air-conditioning design standards.
Comparison of Performance between R290 and R417A in Heat Pump Air Conditioning Water Heater Combination
Authors: Chen Jian Bo , Min Kuang Wei , Li Fen
Published: May 2011

The natural refrigerant R29O and mixed refrigerant R417A is currently approved ideal substitutes of R22, The performance of R290 and R410A in the same heat pump air conditioning water heater combination was studied experimentally, heating capacity, cooling capacity, power input, COP ,discharge pressure, suction pressure,discharge temperature were measured, the performance of heat pump air conditioning water heater combination at standard air condition and varied inlet-water temperature was analyzed .The results show that the most appropriate charge mass of R290 is only 52% of R417A in the same systems ,so using r290 more environmentally friendly.The coefficient of performance (COP) is higher than R417A in the same capacity, so using r290 have lower energy consumption, more energy-saving. Compressor discharge pressure and temperatures of R290 is lower than R417A in the same inlet-water temperature, so using r290 favors the system security operation. But the performance of R290 influenced by the inlet water temperature more obvious than R417A, it's not very suitable for the occasion of high inlet-water temperature.
Simulation Study on the Wall Heat Transferring Characteristics for the Gas-Infrared Heated System
Authors: Gong Ke Qin , Jiang Hong Fang , Guo Sheng Jie , Zhang Da Ying
Published: May 2011

The theoretical analysis and numerical simulation for wall heat transferring process of the gas-infrared heated room is finished in this paper. The thermal equilibrium equation is established, and the heat loss is analyzed between radiant heating system and convection heating system. By means of numerical simulation, the exterior wall surface temperature distribution and the influences of wall blackness to the workspace air temperature as well as the heating energy consumption are studied.
Numerical Study on the Heat Transfer Characteristic in Periodical Variable Cross-Section Channel
Authors: Li Li , Du Xiao Ze
Published: May 2011

The heat transfer characteristic through periodical variable cross-section passage is studied with numerical scheme. The results in multi-period variable cross-section channel show that the heat transfer enhancement can be obtained by forming flow destabilization at large Reynolds number. The parameters include pressure, velocity, temperature in the channel are symmetric about central line at low Reynolds number, then change to asymmetric at high Reynolds number. The variations occur firstly at the downstream near outlet of the channel and move upstream, which could improve the fluid mixing to increase the enhancement of heat transfer in channel.
Influence of Height Difference between Inlet and Outlet Center on Thermal Stratification in Rooms
Authors: Sui Xue Min , Guan Yan Ling , Han Guang Hui
Published: May 2011

For thermal natural ventilation, buoyancy plumes deriving from heating source make thermal stratification in room. The height difference between inlet and outlet is one of the important factors influencing thermal stratification. Taking a representative civil building with inside heating sources as the research object, using the technique of CFD, changing the height difference between inlet and outlet center, this paper gives simulation on the fluid field caused from thermal natural ventilation, analyzes the velocity field and temperature field under different simulation conditions, presents the influence rule of the height difference between inlet and outlet on thermal stratification in rooms. The results can provide a theory reference for natural ventilation system design in domestic buildings.
Study on the Pollutant Control of Industrial Buildings with Mechanical Ventilation
Authors: Wang Yi , Huang Yan Qiu , Li Zhi Peng , Wang Le , Gao Jie
Published: May 2011

The aim of this paper is to study the control effects of pollutants with different ventilation methods in industrial buildings. Comparative researches are conducted between the push-pull ventilation system and displacement ventilation system. Formaldehyde (HCHO) is selected as the main pollutant in the industrial buildings in this paper. The computational fluid dynamics (CFD) is used to analysis the space distribution of pollutant concentrations with the pollution sources at different locations. Through comparative study，the pollutants distribution with the same supply air volume and pollutants diffusion intensity are evaluated from the following two aspects. Firstly, when the height of the pollutant source is 1.2 m in the industrial building, the average concentration of the contaminant at the space section with push-pull ventilation system is relatively higher than that with displacement ventilation system. Secondly, the average concentration with push-pull ventilation system is 0.00058 kmol/m3 while displacement ventilation system is 0.00097 kmol/m3 when the height of the pollutant source is 0.6 m. And when it is 0.3 m, they are 0.00016 kmol/m3 and 0.0017 kmol/m3 respectively. Thus, the concentration of the contaminant in displacement ventilation is higher than the push-pull ventilation’s with the location of the pollution source continuously declining in the height direction.