bluuebunny/crossref_metadata_2025 huggingface dataset:
Seismic Response Analysis of Different Plane Structure in Horizontal Direction
Authors: Li Xue Ling , Yin Xiang Chao , Zhang Hai Bin
Published: September 2011

The results of theoretical research and earthquake damage investigation show that seismic response analysis of different plane structure in horizontal direction is different. Dynamic characteristics and seismic response analysis of four kinds of architectural models with different planes were analyzed by using the finite element analysis software. The inherent characteristics and earthquake time-history curves in different intensity level X, Y direction of displacement, velocity, acceleration and angle displace were studied. The results show that the seismic response of the four kinds of structures separates gradually, and the separation gap increases with increase of earthquake intensity. The building structure is safer in the long side direction than that in the short side in lateral earthquake response. The irregular structure can cause strong response in both horizontal in a single direction of earthquake effect. The second floor is a weak layer of the building structure which should be paid more attention to.
Model Test Investigation of Rock-Fall Impaction to Cut-and-Cover Tunnel Arch Structure
Authors: Wang Yu Suo , Tang Jian Hui , Yan Tao , Zhao Ju Mei
Published: September 2011

On conditions of different weight，height, shape, slope gradient and the property of slope surface, the tunnel portal structure’s strain evoked by rock-fall impaction has been researched in laboratory by using a 1/30 scale similar model. The study shows that there is a simple linear relationship between the structure’s strain , the rock weight and the rockfall height when the slope gradient is specific and the slope surface is slippery and the multiple linear relationship between the structure’s strain , the rock weight and the rockfall height has been obtained. Effect of the shape of the rockfall and the property of slope surface on structure’s strain has been analyzed; The distribution characteristics of the structure’s strain of different parts of one cross-section and the same parts of different cross-sections has been comparative analyed.
Applied Research of Quantitative Analysis Methods to Division of Flood Seasonal Phases for Tanghe Reservoir
Authors: Wang Li Xue , Sun Xiao Dong , Tian Zhao You , Luan Ce
Published: September 2011

Division of flood seasonal phases for reservoir can achieve reasonable adjustments in the flood control levels,and the purpose of improving water use efficiency. This paper refers the recent developments of the division of flood seasonal phases for reservoir research results, applications currently used three kinds of quantitative analysis method for reservoir flood phases. Tanghe Reservoir in Liaoning Province as an application example of the flood seasonal phases. The comprehensive analysis of 3 kinds of theoretical and computational methods based on the results obtained for the optimization of Tanghe Reservoir flood season program.
3D Numerical Simulation of Majiabian Concrete Gravity Dam
Authors: Li Lin Ke , Zhang Ai Jun , Liu Jin Yu , Hou Chun Jiao , Li Hao Dong
Published: September 2011

A new method that 3D numerical simulation combined with anti-cut stability analysis is employed to analyze the stability of Majiabian gravity dam, and the results of the analysis conform to the measured value. And this method can be used in analysis of congener gravity dam. When the results of 2D sliding stability analysis satisfy Code’s requirements, elastic material can be used in 3D numerical simulation. The results of water level sensitivity analysis and deformation modulus of its foundation sensitivity analysis indicates that this gravity dam is insensitive to water level; grouting method can be adopted to enhance its foundation. The results of abutment under tension stress analysis indicate that tension stress of abutment must be considered in high gravity dam design, and arch can be used for reducing the tension stress.
Winter Wheat Water Use Efficiency in Different Scales
Authors: Wang Jing , Yang Jin Zhong , Liu Fu Hai
Published: September 2011

That there existed time and spatial variation for winter wheat water use efficiency (WUE) in different scales in irrigation area could be concluded by studying winter wheat WUE in small scale, middle scale and large scale in irrigation area in 2004~2006 in this paper. It indicated that winter wheat WUE were much more different in the small, the middle and the large scales in different years, which were 1.61kg/m3, 1.30kg/m3 and 0.88kg/m3, respectively. With up scaling, winter wheat WUE was declining in 2004, while increased firstly and then declined in 2005 ~2006.
Combination of Random Waves and Vessel Motions Effects on the Fatigue Damage of Top Tensioned Riser
Authors: Li Xiao Min , Guo Hai Yan , Li Peng
Published: September 2011

As one of the main configurations of the riser, top tensioned riser(TTR) encounters harsh environment in its whole service life. In order to ensure that the riser will fulfil its intended functions, a fatigue assessment should be carried out for each representative riser, which is subjected to dynamic fatigue loading. The fatigue life of TTR under the combination excitation of random waves, current and vessel motion is analyzed in this paper. The long-term stress histories of the riser are calculated and the mean stresses, the number of stress cycles and amplitudes are determined by rain flow counting method. The Palmgren-Miner rule for cumulative damage theory with a specified S–N curve is used to estimate the fatigue life of the riser. The corresponding numerical programs which can be used to calculate the response and fatigue life of the riser are compiled. The significant influences of internal flow velocities and low frequency motion of the vessel are analyzed in detail.
Study on Chloride Ions Erosion Model of Concrete Buildings in Irrigated Area
Authors: Xu Cun Dong , Hou Hui Min , Wang Yan , Zhai Lu Xin , Ma Zhong Liang
Published: September 2011

Chloride ions are the main factors of concrete building in irrigated area. Through the analysis of the failure mechanism which chlorine ion to the building in irrigation return water, the mathematical mode is established to forecast the service life of buildings in high salinity groundwater erosion environment.
Study of the Effects of Rainfall Infiltration on Stability of Geocell Protection of Slope
Authors: Wang Guang Yue , Han Yan
Published: September 2011

Geocell protection of slope was influenced by environment and climates largely. Many of them came to failure when subjected to rainfall infiltration. Aiming at the general shear failure mode of the geocell-protection-system (GPS), its stability analysis model during rainfall was established by the limit equilibrium method. A new approach of evaluating stability of the GPS was proposed.
Research of the Erosion Mechanism and the Repair Technique about the Concrete Building of High Lifts Water Irrigation Project
Authors: Hou Hui Min , Fan Jian Ling
Published: September 2011

This paper studys on how the high degree mineral groundwater erodes the concrete building of great high lifts irrigation project in JingDian (GanSu province) and GuHai (NingXia province), and analyzes the break reasons for erosion and investigate the repair technique. In the idea of reducing the erosion medium and enhancing the concrete anti-erosion quality, the authors suggest a popularized repair technique and protection measure about the break reasons for erosion of the concrete building of high lifts water irrigation project in loess plateau regions.
An Experimental Study of Soft Rock Roadway with Anchored Support Structure Based on Nested Mechanical Analysis Model
Authors: Liu Fu Sheng , Dong Gang Gang , Wang Su Hua , Wang Shao Jie , Song Yang
Published: September 2011

This paper chooses anchored support engineering of ore dynamic pressure soft rock roadway Qinan, Huaibei city as an example, and with the help of nested mechanical analysis model of anchored support structure, the paper analyzes the range of elastoplasticity, the range of anchor note area, stress and displacement of original rocks of the reinforced project, and simulates three-dimensional finite element numerical and underwent engineering detection of the project. Practicality and validity of quantitative control design method of anchored support structure are proved by comparing the theoretic research, calculation results, and field measurement results.
Numerical Experimental Research on the Hydrodynamic Performance of Flow around a Three Dimensional Circular Cylinder
Authors: Fang Yuan Yuan , Han Zhao Lin
Published: September 2011

Using the CFX software and the Large Eddy Simulaion (LES) method, this paper numerically simulates the hydrodynamic characteristics of the flow around a 3d circular cylinder at high Reynolds number (Re=5.6×103, 2.8×104, 1.1×105). The numerical simulation focuses on investigating the vortex shedding angle, the characteristics of the vortex shedding and the vortex tube, the base pressure, the static and the fluctuating drag and lift. The result of calculation shows that the forces of every section along the span of cylinder are symmetrical with respect to the middle section. Moreover the flow around the cylinder obviously appears three dimensional characteristics at high Reynolds number.
Outlier Identification and Correction Online for the Ocean Geomagnetic Parameter Measurement
Authors: Xu Zun Yi , Wei Dong , Yan Lei
Published: September 2011

The outlier identification and correction of the geomagnetic parameter measurement is an important influencing factor for the probability and precision of the matching algorithms. The ream-time measurements of the geomagnetic field parameter can be considered as the first-order non-stationary random process, the real-time measurement value can be predicted by using the multi-level recursive method, the outlier identification can be done by the Dixon criterion, and the correction can be made by using the median filter and the one step prediction value. The inspection is carried out by using the emulation data and actual data, the results show that not only the isolated type but also the spot-type outlier value can be detected well and the signal reconstruction error is less than 5%.
Algorithm for VRS Based on Star Structure
Authors: Gao Cheng Fa , Shen Xue Feng
Published: September 2011

In view of the deficiency of algorithm for VRS (Virtual Reference Station) based on the triangular network, a novel algorithm for VRS which is based on star network is proposed. Firstly, a kind of baseline solution method of network RTK/VRS based on star structure is established and an ambiguity resolution method is also proposed in this paper. Then further research is done to analyze the algorithm of ionospheric and tropospheric correction separately. Finally, the network ambiguity resolution and correction calculation in both star structure network and traditional triangular network are verified and analyzed through two tests. These tests indicate that the Network RTK (VRS) based on star structure this paper proposed can obviously accelerate the fixed time of network ambiguity resolution, which can be up to 50%, and can achieve higher precision and reliability in the generation of network correction.
Research of Remote Sensing Image Segmentation Based on Mean Shift and Region Merging
Authors: Cui Jian , Ma Dong Ling , Yu Ming Yang , Zhou Ying
Published: September 2011

In order to extract ground information more accurately, it is important to find an image segmentation method to make the segmented features match the ground objects. We proposed an image segmentation method based on mean shift and region merging. With this method, we first segmented the image by using mean shift method and small-scale parameters. According to the region merging homogeneity rule, image features were merged and large-scale image layers were generated. What’s more, Multi-level image object layers were created through scaling method. The test of segmenting remote sensing images showed that the method was effective and feasible, which laid a foundation for object-oriented information extraction.
Tilt Measurement Research Based on Moirefringetechnique of SLR Digital Camera
Authors: Zhu Rui , Zheng Wen Hua
Published: September 2011

This paper analyzes the reason and condition of the generation of moire effect when taking photos with a digital camera, further studies a new tilt measurement method based on moire effects of SLR digital camera and then develops the general application of moirefringetechnique.
Gravity Anomaly Detected by GOCE in China’s Western Region
Authors: Xu Hai Jun , Zhang Yong Zhi , Duan Hu Rong
Published: September 2011

In this paper, gravity anomaly in China’s western region is computed using GOCE data and GRACE data respectively. The result shows the gravity anomaly computing by GOCE data can reflect the spatial distribution characteristics of regional tectonics and seismic activity. This new technology provides a new observed method to study seismic activity. The spatial resolution of GOCE is more higher than GRACE.
Study on Key Technology in the Control Surveying of Jinan-Qingdao Highway’s South Line
Authors: Wang De Bao , Fang Xue Ling
Published: September 2011

The south line of Jinan Qingdao highway (which is short of Ji-Qing south line) spans 281km, whose geomorphy is mainly composed by mountain lands and hills. Approximately, it runs from east to west and straddles several projection zones. Systemic conformance of its layout and measurement, high precision in company with multifunctional planes and vertical control nets make up this project’s key technological problems. The report tells of the selection of central meridian in different areas of Ji-Qing south line and the layout, observation, adjustment, height fitting and precision statistics of GPS control network; the layout, observation, adjustment and precision counting of vertical control nets; Meanwhile, it analyses and discusses that how to guarantee the systemic conformance of coordinate system and vertical datum, together with eliminating the division of points’ coordinates and elevation values’ steps when primary survey design are being made synchronously in two super highways or in different areas of the same expressway.
Determination of Seasonal Variations of Low-Degree Earth Gravity Field from CHAMP Geometric Orbits
Authors: Liu Xin , Guo Jin Yun , Kong Qiao Li , Li Guo Wei
Published: September 2011

Based on satellite dynamics, 1 year’s CHAMP geometric precise orbit data are used in this paper to fit the satellite orbits by Cowell II numerical integral and partitioned Bayesian least square parameter estimation. Time series of low degree geopotential coefficients and are respectively calculated, which reflects obviously seasonal variations of and . The results / month, /month indicate the geodynamical shape of the earth is getting rounder and rounder and at the same time its pear-shaped component adds gradually.
Study Improved Background Value Functions of Non-Equidistance GM(1,1) Model in Surveying and Mapping Engineering
Authors: Deng Yong He
Published: September 2011

There are some losed datum or mistake datum when GM（1，1）model deals engineering matter,so equidistance GM(1,1) model is restricted and choosing non-equidistance GM(1,1) model is very necessary.The backgroung value functions of modeling research on non-equidistance GM(1,1) model is studied and is considered to be wrong,and strict backgroung value functions is advanced in the paper.The theory and practice approach of the strict method is introduced particularly.Feasibility and validity of this mothod is gained through surveying and mapping engineering .So, the paper has some significance of theory and practice.
Numerical Analysis and Evaluation on Supporting Parameters in Coal
Authors: Li Ting Chun , Wang Hui , Xing Xue Yang , Zhang Yu Qing
Published: September 2011

At the turn of the last century, bolt supporting of coal roadway had rapidly developed with the applied range of bolt stretching continually. The bolt supporting in roadway has been implemented widely. But until now, there is no reliable theoretical support or appraisal system on the design of bolt supporting roadway and the evaluation of supporting conditions. Supporting effect is tested only by practice and roof-fall accidents take place repeatedly. This paper conducts the research on the bolt supporting parameters in No.315 transportation-up-hill roadway of Nan Ye Coal Mine with numerical analysis method; it is discovered that numerical analysis can be a good way to predict and evaluate roadway supporting effects to be worthy popularizing.
Research into the Model of GNSS Leveling Polynomial Surface Fitting Based on MATLAB
Authors: Gong Yu Sheng , Han Qian , Zhang Li Ping
Published: September 2011

To make full use of geodetic height results measured by GNSS and improve the accuracy that GNSS geodetic height convert to normal height, method of polynomial surface fitting has been selected in this article to research into fitting of the elevation. In the first place, for least squares estimation do not have the ability of resisting gross error, robust estimation is introduced to data preprocessing, which has solve the problem of distortion model effectively and then combines with specific engineering to make comparison and to analyze accuracy of polynomial surface fitting data of different orders. MATLAB has been used in programming design in the whole process, which has realized automatic processing of data.
The Coagulation Performance and Floc Properties of Polymeric Ferric Aluminum Chloride - Polydimethyl Diallylammonium Chloride Coagulant during Surface Water Treatment
Authors: Sun Cui Zhen , Liu Jian Guang , Zhu Li , Qi Feng
Published: September 2011

In this paper, new composite coagulants, polymeric ferric aluminum-polydimethyl diallylammonium chloride, were synthesized by combing Polymeric ferric aluminum chloride (PFAC) with polydimethyl diallylammonium chloride (PDMDAAC) under different molecular weight ratio (Aluminum to PDMDAAC, Wr=10, 4, 2 and 1). Furthermore, flocculating mechanisms and performance of these new composite coagulants were investigated in treating surface water. The growth of flocs during coagulation using composite coagulants were measured under optimal dosage and neutral conditions. The results indicated that the new composite coagulants exhibited better coagulation performance than PFAC for removing turbidity and dissolved organic matter. For the composite coagulants, the predominant coagulation mechanisms were bridge formation and charge neutralization.
Kinetics of Pumice Catalyzed Ozonation of Trace p-Chloronitrobenzene in Aqueous Solution
Authors: Yuan Lei , Shen Ji Min , Chen Zhong Lin
Published: September 2011

The kinetics of pumice for decomposition of p-chloronitrobenzene (pCNB) in aqueous solution were investigate. The experiment result indicated that ozonation alone and pumice-catalyzed ozonation of trace pCNB in aqueous solution followed the Pseudo-first-order kinetic model at the reaction temperature of 296 K and the initial pH of 6.86. The rate constant of pumice-catalyzed ozonation increase 149% compared with ozonation alone. In two processes mentioned above, the rate constants of degradation of pCNB were found to decrease with increasing of tert-butyl alcohol. The rate constant of ozonation alone appeared to be decreased 73%, respectively, decreasing 194% in the process of pumice-catalyzed ozonation. Under the conditions of this experiment, ozonation alone and pumice-catalyzed ozonation for degradation of pCNB were primarily oxidized by highly active hydroxyl radicals.
Economic and Environmental Assessment of Pulp and Paper Industrial Wastewater Treatment
Authors: Hong Jing Min , Ismail Zainab. Z , Hong Jing Lan
Published: September 2011

A cost combined life cycle environmental assessment was carried out to estimate the economic and environmental impact of wastewater treatment in the pulp production site of China. Results showed that the impact seen from abiotic depletion, acidification, eutrophication, global warming, fresh water aquatic ecotoxicity, and marine aquatic ecotoxicity categories represented an important contribution to the overall environmental impact, while the impact seen from human toxicity, terrestrial ecotoxicity, and photochemical oxidation categories played relatively small role. Specifically, the machine, electricity, coagulant production processes had the highest contribution to the overall environmental and economic impact. Improving electricity and chemicals applications efficiency are the efficient way to minimize overall environmental and economic impacts.
Analysis of Full-Featured Pump Curve to Study the Impact of Large Diameter, Long Distance and High-Lift Water Pipeline
Authors: Yang Yu Si , Liu Li , Li Kun
Published: September 2011

According to the situation of Chinese urban water supply, this article has analyszed the possibility and computing method for water hammer that caused by pump stop in large diameter and high-lift water pipelines. In addition the impact of Full-featured Pump Curve on the water hammer calculation are also discussed. Finally, using the water hammer calculation of the primary pumping stations within a water-supply project which located in northeast China as an example, we had made corresponding conclusion.
Study on Nitrite Accumulation in Biological Aerated Filter Treating Municipal Wastewater
Authors: Zhang Shou Bin , Qiu Li Ping , Li Hong Lan
Published: September 2011

The nitrite accumulation in Biological Aerated Filter (BAF) treating simulated municipal wastewater was investigated and the possibility of nitrous nitrification in low ammonia wastewater treatment was discussed. The results indicate that the lower concentration of DO was of advantage to the formation of the nitrite accumulation. When the concentration of DO was controlled to less than 0.5 mg/L, the nitrite accumulation rate can improved significantly to the maximum over 80%. By adjusting pH, nitrite accumulation can take place in BAF. When the influent pH value was 6.5 to 7, the highest nitrite accumulation rate was 57%. But long-term stable nitrite accumulation cannot be obtained only through changing influent pH value. The increasing of hydraulic loading can contribute to nitrite accumulation. When the hydraulic loading was enhanced to 10 m3/(m2•h) , the average nitrite accumulation rate can be increased by 52.5 times. When concentration of DO was 1.0 to 1.5, influent pH was 6.5 to 7 and the filtration rate was 5 m/h, the nitrite accumulation of BAF reactor was of good stability. During 60 days’ running, the nitrite accumulation rate can keep at 65% to 75% stably and obvious nitrous nitrification was found.
The Computational Analysis of Parameter Setting on Secondary Network Distribution Heat Source in Central Heating System
Authors: Zhao Zhi Ming , Sun Chun Hua , Qi Cheng Ying , Xia Guo Qiang , Hu Jian Jun
Published: September 2011

Two combined operation modes of basic heat source and distribution heat source are described, the possible values of basic heat source capacity coefficient α under these two combined operation modes in each region with heating provision are explored, the theoretical calculation formula of distribution heat source opening temperature and closing temperature is derived, and figure out distribution heat source opening temperature and closing temperature of each region with heating provision according to the recommended basic heat source capacity coefficient α, draw that if heating temperature is 5°C, distribution heat source can not only reinforce the peak, but also run the valley in these regions which are colder than Yinchuan, but distribution heat source can only reinforce the peak in other regions.
Methods of Excavation Core Drilling
Authors: Soldatenko Andrey , Jiang Hong Yuan , Danilov Alexander
Published: September 2011

The article reviews the basic principles of interaction between the cutting tools with the ground. Their advantages and disadvantages. It is carried out to determine the degree of relevance of the issues under research and to clarify the currently existing methods of solving them. We are especially interested in frozen soils, because the problem of the frozen soils’ development is one of the most serious to date. Most of the unexplored territories of the world lie under the snow cover in winter times. In the extreme north an acute problem of dealing with permafrost soils demands a rapid optimization of the cutting processes applied to frozen grounds. To this end, we developed a special milling and boring rig BME-2000 (Bore-Milling Equipment 2000), based on a machine excavator. It works on the principle of core drilling and is designed to develop permafrost and extremely durable surfaces such as asphalt and concrete. This article will try to formulate all the necessary questions for further research studies and to set objectives for further optimization of the cutting processes based on the BME-2000 as a comparison model. This will be done through a review of all known principles of excavation and existing machinery that deals with the development of soils/frozen soils and very durable surfaces.
Analysis of the Influence that Residential Building Indoor Temperature Controls for Heating Energy Consumption
Authors: Wang Yue Ren , Zhang Jing , Xue Cong , Wu Nan
Published: September 2011

By using household heat metering system，people can control indoor temperature according to their economic conditions and the requirement of thermal comfort. In this paper, DeST-h is used to simulate the energy consumptions of architecture heating in different temperature, which compare to the situation that not use temperature control simulation, to analysis the heating energy saving potential in domestic architecture in Shenyang. So as to develop people’s consciousness of energy saving, and to provide the quantized datat for decision-makers to make relevant policies.
AHP-Based Method for Military Defence Project Risk Assessment
Authors: Liu Bao Hua
Published: September 2011

Based on the risk type classification of model development project, the paper used the analytic hierarchy process (AHP) method, established a AHP risk assessment model of development project, and described the risk assessment idea.
Optimum Performance Characteristics of an Irreversible Four-Temperature-Level Absorption Refrigerator
Authors: Huang Yue Wu , Sun De Xing
Published: September 2011

The optimal performance of an absorption refrigerator operating between four temperature levels with the losses of heat resistance and internal irreversibility is analyzed first by taking the total heat transfer area of heat exchangers as an objective function. The minimum total heat transfer area is described in terms of the rate of the entropy changes of four heat reservoirs, and the generally optimal relation among the cooling load, the coefficient of performance and total heat transfer area is achieved. Then, an ecological optimization criterion is proposed for the best mode of operation of the absorption refrigerator. We investigate the ecological optimization performance and derive the corresponding cooling load, coefficient of performance and entropy production rate at the maximum ecological criterion for the absorption refrigerator. A comparison of an absorption refrigerator performance under maximum ecological function and maximum cooling load conditions is presented. Effects of the cycle parameters on the ecological performance have been discussed.
Analysis of Heat Loss of Ground Pipeline of Thermal Production Oilfield
Authors: Liu Jian Jun , Pei Gui Hong , Ji You Jun
Published: September 2011

Steam stimulation is one of the main methods used in heavy oil reservoir development. How to inject high temperature and high dryness steam is a key factor to enhance heavy oil recovery. It is significant to evaluate heat transfer of steam pipeline and optimize thermal insulation layer for heavy oil exploitation. Based on fluid mechanics, heat transfer theory, considered phase change, mathematical model to calculate heat transfer and heat loss of steam pipeline was derived. Using COMSOL Multiphysics, a finite element based program for simulating unlimited multiphysics and single physics applications, the author simulated heat transferring in ground steam pipeline and analyzed the effect of thermal insulation layer. From the simulation results, it was known that, (1) Along with the pipeline distance increases, the steam dryness decreases, the decrease rate decreases with the distance increases. (2) At the same transmission distance, the bigger the thermal insulation layer thickness is, the smaller the heat loss of the steam is. The heat loss of steam transmission mainly center on the first half pipeline. (3) With the thickness of thermal insulation layer increases, the heatloss declines. After the thickness of thermal insulation layer increases 90 mm, increasing the thickness has no obvious effect on reducing the heat loss. So, it is suggested that the thermal insulation layer thickness should be 75-80mm.
Matching of the Pump Lift in the Distributed Power System
Authors: Fu Yong Zheng , Liu Hui Hui , Yao Yuan , Li Ling Ling
Published: September 2011

We can calculate various pump lifts utilizing the method of solving the pressure balance loop equations in the distributed power system. For the system pumps are set at heat (cold) source and on each branch, if the number of independent loops is less than the pumps, the equations of the pump lift have multiple solutions. When considering the constraint conditions, if we determine the pump lift of the first branch, others can be determined. For the system pumps are set on the main pipes, if we install pumps at heat (cold) source and on each main water supply and backwater pipes, and the pumps of a corresponding pair of main water supply and backwater pipes are the same, when the number of independent loops is equal to the pump lifts, the equations can have solutions. Furthermore, the method can also be applied for other systems where pumps are set on the main pipes, and the equations of the pump lift have a unique solution.
The Temperature Field Finite Element Analysis of Concrete Beam after Fire Based on ABAQUS
Authors: Li Wen Sheng , Deng Xiao Wu
Published: September 2011

Based on ABAQUS software platform, the author analyzed the concrete beam’s temperature field by the finite element numerical simulation technology,and got the temperature field and the measuring temperature-time curve for the beam of different sections.The calculated results made a perfect coincide with on-site test ,which proved that ABAQUS simulated temperature field of concrete component has certain precision .Thus, the results provided the references for those who want to do more in-depth studies of the concrete beam’s mechanical properties after fire and reinforcement design.
Experimental Investigation on Triaxial Rheological Mechanical Properties of Biotite Granitic Gneiss
Authors: Jiang Yu Zhou , Wang Rui Hong
Published: September 2011

In order to know about the rheological properties of typical biotite granitic gneiss in Xiaowan Hydropower Project, triaxial rheological experiments with biotite granitic gneiss were carried out on the rock servo-controlling rheological testing machine. As a result the typical complete rheological curve of the biotite granitic gneiss indicates that when the stress level is low, the rheological deformation of rock specimen is not obvious; when in high stress conditions, the rock mass rheological properties are very significant with large rheological deformation, including three typical rheological phases. The rheological deformation decreases with the increase of the confining pressure, and at the same time the rheological rate of rock specimen changes with the change of stress level. In low stress state, the corresponding rheological rate of the rock specimen incarnated as the rheological rate attenuation stage and the rheological rate uniform stage, while once the stress level exceeds the long-term strength of rock specimen, the rheological rate would first decreases and then keep at a constant value, and finally it will trend to follow the non-linear acceleration law. The rupture form of the low-intensity biotite granitic gneiss specimen is the main crack surface which causes the damage of rock specimen, and finally generated by the expansion and transfixion of the crack in the initial cavern flaw. The rheological deformation and rupture form of rock specimen in different confining pressures are not exactly the same.
Experimental Study on Detecting the Building Damage Caused by Fire with Acoustic Emission Technique
Authors: Lv Jun Li , Dong Yu Li , Sun Jian Dong
Published: September 2011

Acoustic emission technique is a non-destructive detection method that can continuously and dynamically detect the damage evolution inside the structure. In this paper, a local fire experiment is conducted within an entity building to acquire and analyze acoustic emission parameters in the whole process of the experiment. Results show that the number of events is closely related to the crack development, the peak value of the energy rate occurs when a large number of cracks appear, signals with the amplitude less than 80db account for more than 90%, signal amplitudes produced by the building damage in different stages from fire development to fire attenuation are different, and most signals with the amplitude of 75db – 85db are produced in the stage of fire development.
An Experimental Study of the High Temperature Behavior of Concrete Slabs Strengthened with Carbon Fiber Reinforced Polymer (CFRP) with Inorganic Adhesive
Authors: Zhang Xin , Zhang Guo Qiang
Published: September 2011

Nowadays the mechanical properties of epoxy resin used to paste CFRP strengthening the concrete structures, has a sharp drop in more than 60°C. Four CFRP-strengthened concrete one-way slabs were studied in the fire, one using epoxy resin and the other three using inorganic adhesive (Magnesium Oxychloride Cement). The experimental results show that :(a) The fire resistance performance of CFRP-strengthened concrete slab by inorganic adhesive with 15mm thickness fire protection was better than the slab without fire protection; (b) Without considering the impact of burst, the fire resistance performance of CFRP-strengthened concrete slab by inorganic adhesive with 30mm fire protection was better than the slab with 15mm fire protection;(c)Under the same fire protection measures, the fire resistance performance of CFRP-strengthened concrete slab with inorganic adhesive was better than the concrete slab strengthened with CFRP by epoxy adhesive.
Shear Size Effect Analysis of Reinforced Concrete Column Based on Truss-Arch Model
Authors: Xie Yong Ping , Li Zhen Bao , Song Jia , Du Xiu Li
Published: September 2011

With the development of modern constructional technique, more attention on the size effect is paid by academics and engineers. Shear failure mechanism of reinforced concrete column is analyzed firstly, and then the advances on the size effect of reinforced concrete column is introduced. the effects of sectional size on the shear behaviors of reinforced concrete column is studied by theoretical analysis and experimental summary, and the formula of the size effect of shear resistance of reinforced concrete column is proposed.
Evaluation and Governance Design of Risk Factor of Debris Flow on Gunmaling
Authors: Nie Lei , Xu Li Na , Yu Yan Xin
Published: September 2011

Abstract: It is analyzed and obtained the result that the debris flow is currently in mature stage with medium risk and high occurrence through the gray correlation method of fractal research and effect measure of debris flow gully. Therefore, it is necessary to take corresponding governance measures. In this article, check dam is used as main preventive engineering measures to set up two check dams in the passing area of debris flow, with total capacity about 2800m3 and design reservoir capacity of flood once per 50 years. Construction of the check dam will effectively reduce risk of debris flow.
Evaluation Method of Urban Comprehensive Disaster-Carrying Capability Based on Fractal Theory
Authors: Wang Wei , Tian Jie , Wang Zhi Tao , Guo Xiao Dong , Ma Dong Hui
Published: September 2011

In order to correctly evaluate urban comprehensive disaster-carrying capability and then to establish scientific basis for disaster prevention and reduction, a fractal method for urban comprehensive disaster-carrying capability is proposed on the basis of system principle which is that structure determines function. The fractal dimensions of 29 cities are calculated and analyzed. The results show that relative stronger, middling and weaker are respectively 13.79%, 65.52% and 20.69%, which are completely consistent with the actual situation. So the method can construct a characteristic index, and the main impact effects can be analyzed according to the result. Tested by examples together with the other two methods, i.e. the fuzzy assessment method and exponent method, the results verify effectively that this method is useful and feasible.
Comparative Analysis of the Numerical Simulation Results Using ConWep Algorithm with the Experimental Results
Authors: Luo Zhong Xing , Luo Kun Sheng , Zhao Yue Tang , Huang Jie Ji
Published: September 2011

The keyword LOAD_BLAST in LS-DYNA has been established to simulate the response of the structure under blast loading since V960. The ConWep algorithm in it is described in this paper. As the load and impulse computed by keyword LOAD_BLAST are smaller than those they should be, the accuracy and reliability of parameters in keyword LOAD_BLAST should be verified and adjusted according to the experiment results of the blast loading on blast door. The results show that the load and impulse computed by ConWep module in LS-DYNA will be close to the experimental results when the TNT equivalent in keyword LOAD_BLAST is multiplied by a factor of 1.35.
Adaptive Research on Urban Shelter and Evacuation System Plan Coping with Catastrophe
Authors: Liu Chao Feng , Su Jing Yu , Wang Wei
Published: September 2011

Taken examples of recent major disasters，the deficiencies of shelter and evacuation system in planning，construction, etc.. and the inadaptability of protecting security needs of the city under extreme disasters is analyzed. Given this, on the basis of the analysis of the connotation of catastrophic environment and adaptation and the relationship between them, the concept of adaptive planning of urban shelter and evacuation system under the disastrous environment is proposed. Based on dynamic planning idea, the adaptive planning is preliminarily discussed in the three perspectives of disaster prevention functions, fortification level, hierarchical structures and spatial characteristics and some planning strategies and measures coping with catastrophes are given.
State-of-the-Art Review on Anti-Ram Bollards
Authors: Hu Bo , Li Guo Qiang , Chen Su Wen , Shi Wen Long
Published: September 2011

Perimeter protection is an important physical protection approach for buildings and infrastructures, which is also regarded as the first line of protection. Vehicle borne improvised explosive devices (VBIED) have been recognized as a major design threat by many government agencies for years, since they have been so extensively used in past terrorist attacks against critical buildings and infrastructures. Preventing unauthorized vehicles from approaching a protected area with vehicle barriers installed in perimeter of the buildings and infrastructures would consequently reduce blast and debris threats. The history of test certification standard for vehicle barriers is briefly reviewed. The research achievements on anti-ram bollards, one type of vehicle barriers, in the fields of crash test, numerical simulation, and design theory are presented. The remaining problems and deficiencies of the research are pointed out and the corresponding proposals are put forward. Finally, some further research works on anti-ram bollards are proposed.
The Analysis on Shape Coefficient of Low-Rise Buildings Wall
Authors: Zhou Ji , Dou Yuan Ming , Sun Ji Shu
Published: September 2011

In order to improve the wind resistance of single-storey house in the rural areas, this paper has carried countryside house's rigid model on the wind tunnel test in view of the south area. This paper has studied coefficient distributed rules of the single-layer house building and calculates the shape coefficient under various wind angles, and draws the build coefficient distribution figure finally. The result indicated that when the wind angles are 0 or 90 degrees, the front wall is most unsafe. When the wind angles are 60, 90, 150, 180 degrees the back wall is unsafe. When the wind angles are 0, 180 degrees wind angles, the flank wall are unsafe. But speaking of the entire house, 0 degrees wind angles is the unsafe wind angles.
Algorithm and Program for Simulating Heat Transfer in Cavities of Structural Members under Fire Conditions
Authors: Liu Yong Jun , Wang Dong , Ma Xing Tao
Published: September 2011

In this paper, an algorithm based on the network method suggested by Oppenheim for calculating the radiative heat flow in a cavity of structural members, say hollow core concrete slabs, exposed to fires is presented. It is assumed that the pressure in a cavity keeps atmospheric pressure through the whole cause of a fire, and the lost heat from the air due to expansion and immediate moving away from a cavity is neglected. The heat in a cavity is transfer via both heat conduction in air and thermal radiation among boundaries, and special regard is paid to modeling heat transfer by radiation. The effective radiative heat flow system of equations is derived and expressed in matrix form. The system of equations features a symmetric coefficient matrix, which can be stored in a one dimensional array, and can be solved using LDLT factorization. Node radiative thermal loads are calculated from effective radiative heat flows at edges of elements located on internal cavities. The nonlinear finite element program TFIELD written by first author has employed the new algorithm. Temperature distribution in two structural members with cavities are calculated using TFIELD, and numerical results demonstrate that the new algorithm is very effective and is useful for further study of structural behavior of structural members under fire conditions.
Soil Parameter Identification Based on Field Monitoring Value of Displacement and Stress in Pit Retaining Structure
Authors: Wang Fei , Song Jian Xue
Published: September 2011

Parameter-M is the proportion factor of horizontal soil reaction when the soil is compressed horizontally, and the corresponding method of pit retaining structure analysis is named as M-method. M-method is widely used to determine the working state of pit retaining structures in China, however, parameter-M varies significantly when deduced by different approaches. An analysis unit is chosen in the subway station pit in Zhengzhou, center of China, on the bank of Yellow River. The retaining structure consists of reinforced concrete piles, internal bracing struts made of steel pipes. The horizontal displacements of retaining piles and the axial forces in pipe bracing struts are monitored in-situ. Then, calculation assumption is taken as that during the elastic deformation stage, parameter-M for each soil keeps constant. Then a series of equilibrium equations of forces acting on retaining structure are set up to determine the values of M for each soil corresponding to deferent stages of excavation. When the identified values of M are applied in the later projects, it shows the validity and accuracy of the method. Precise values of M are applied in the similar geological sites to optimize the retaining structure design.
The Reinforced Concrete Structural Vulnerability Analysis under Earthquake Loads
Authors: Ye Ya Qi , Ren Hui Qi , Wu Xiang Yun
Published: September 2011

The structural vulnerability analysis decides the probability of the structural failure under the earthquake loads. According to the seismic failure and the failure mechanism of the structure, this paper defines the structural resistance with the limit states of the structural function and builds the probability relation between the structural failure and the structural resistance with which the failure probability of a structure under the load of some intensity earthquake can be decided and the curves of structure vulnerability can be drawn. With this method the structural tolerance of earthquake loads can be evaluated and the safe reliability of the structure can be predicted.
Environmental Impact Analysis and Control Measures in Tunnel Construction
Authors: Jia Lei , Lei Ting , Yan Song Hong
Published: September 2011

The impact of tunnel construction upon the environment is analyzed from the perspective of ecology, air, sound and society respectively. In the case of Three Ponds Tunnel, risk assessment is made on the environmental impact in different stages of tunnel construction. Environmental protection measures are put forward, which can serve as reference for environmental protection in the construction of similar geotecnical engineering projects.
A Regularization Homotopy Iterative Method for Ill-Posed Nonlinear Least Squares Problem and its Application
Authors: Tang Li Min
Published: September 2011

A regularization homotopy iterative method established for ill-posed nonlinear least squares problem. Two new regularization parameter selecting strategies are proposed, which are called direct search method and interval division method. The calculation results of nonlinear least squares problems show that the regularization homotopy iterative method and parameter selecting strategies proposed in this paper are correctly and applicable. And also calculation results of nonlinear adjustment of free networks with rank deficiency of Jianglong bridge pier displacement defor-mation monitoring control network show that the method not only decrease the iterative matrix con-dition number, but also make the condition number small fluctuation in full iterative process.
A Constrained Delaunay Triangulation Algorithm Based on Incremental Points
Authors: Wu Bai Chao , Tang Ai Ping , Wang Lian Fa
Published: September 2011

The foundation ofdelaunay triangulationandconstrained delaunay triangulationis the basis of three dimensional geographical information system which is one of hot issues of the contemporary era; moreover it is widely applied in finite element methods, terrain modeling and object reconstruction, euclidean minimum spanning tree and other applications. An algorithm for generatingconstrained delaunay triangulationin two dimensional planes is presented. The algorithm permits constrained edges and polygons (possibly with holes) to be specified in the triangulations, and describes some data structures related to constrained edges and polygons. In order to maintain the delaunay criterion largely，some new incremental points are added onto the constrained ones. After the data set is preprocessed, the foundation ofconstrained delaunay triangulationis showed as follows: firstly, the constrained edges and polygons generate initial triangulations，then the remained points completes the triangulation . Some pseudo-codes involved in the algorithm are provided. Finally, some conclusions and further studies are given.