bluuebunny/crossref_metadata_2025 huggingface dataset:
Estimating ESD Properties of Fabrics Based on Correlation between Dielectric Losses and Charge Decay Time
Authors: Donciu Codrin
Published: November 2013

ESD garments are used to protect sensitive devices from electrostatic discharges that can occur from the normal clothing of the human operators. Over the years, researchers implemented different structures of fabrics that can be used in ESD garments and studied their ESD properties using different methods. The current paper presents the possibility to use the information obtained from dielectric spectroscopy in order to evaluate the fabrics electrostatic charge decay time and investigates the presence of a correlation between the losses factor tan (δ) and the electrostatic charge decay time.
Modeling of Strain and Stress States for Straight Rods with Particular Cross Sections Subjected to Torsion
Authors: Glovnea Marilena , Suciu Cornel
Published: November 2013

In the case of shaft-hub joints with cylindrical pins found in both macro and micro-devices, a longitudinal gutter with an almost half-circular cross section is practiced along the length of the shaft segment. The center of the circular arc is placed on the circular edge of the cross section. The present paper aims to model strain and stress states within such a shaft, when the material elastic properties are known along with shaft segment length and applied torque. Using the MathCad environment, 3D and constant stress level plots were obtained for the distribution of tangential stresses over the cross section. After application of torque, the transverse cross sections shift and become anti-symmetric as illustrated by the obtained 3D and constant strain plots.
The Influence of Thermal Treatment upon Nanostructure and Composition of YZrO Based Ceramics Obtained by Atmospheric Plasma Spraying
Authors: Pintilei Geanina Laura , Brânza Florin , Nica Valentin , Strugaru Sorin Iacob , Bârcă Eduard Sebastian , Munteanu Corneliu
Published: November 2013

This paper presents a concept of thermal barrier coating used to prevent exfoliation and increase the maximum working temperature of a turbine engine. The coating consist of a ZrO2/20%Y2O3 ceramic layer and a NiCrAlY adherent layer, deposited by atmospheric plasma spraying (APS), on a Ni super alloy sample usually used for the manufacturing of turbine blades. The sample was subjected to thermal treatment and after that analyzed. SEM images of the samples were taken, to analyze their behaviour to thermal treatment. . Reference sample (without thermal treatment) and samples subjected to 5, 10 and 15 hours heat treatment were investigated using X-ray diffraction in 25-130o 2θ interval.
Analysis of Rails of a Ferry Boat under Wheels Contact Loading
Authors: Axinte Tiberiu
Published: November 2013

The paper presents the effect of the discontinuity of the rails of a ferry boat and the presence of lower modulus insulation material at the gap to the variations of stresses in the insulated rail. The analysis consists of a three-dimensional wheel rail contact model based on the finite element method. One of the results shows that the maximum stress occurs in the subsurface of the railhead of the ferry boat. The ratio of the elastic modulus of the railhead and insulation material is found to alter the levels of stress concentration. Numerical result indicates that a higher elastic modulus insulating material can reduce the stress concentration in the railhead but will generate higher stresses in the insulation material, leading to earlier failure of the insulation material. A general subsurface crack propagation analysis methodology is used for the wheel and rail rolling contact. The fatigue damage in the wheel is calculated using a previously developed mixed-mode fatigue crack propagation model. The advantages of the proposed methodology are that it can accurately represent the contact stress of complex mechanical components and can consider the effect of loading non-proportionality. The effects of wheel diameter, vertical loading amplitude, initial crack size, location and orientation on stress intensity factor range are investigated using the proposed model. The prediction results of the proposed methodology are compared with in field observations. The contact elements were used to stimulate the interaction between a wheel and a railhead. Variations in contact stress fields at various locations of the rail are sensitive to the contact distance. The location of the maximum von Mises stress was shifted to the contact surface as the contact point moves close to the rail end. A higher stress, larger deflection and significant plastic deformation occurring at the rail from ferry boat may lead to deterioration at the rail end.
Statistical Model for Ultra-Wide Band Radio Channels Onboard Ship
Authors: Deacu Daniela
Published: November 2013

Modeling of radio wave propagation onboard ship should take into account multipath effects, i.e., reflection and scattering on the ship conductive superstructure. Novel ultra-wide band communication technology consists of series of short pulses carrying information by changing the polarity as 0 or 1 bits are transmitted. Multipath effects actually impact on the interference free time-slots to be provided between carrier pulses. Narrow-band radio channels are presently modeled either deterministic or stochastic. Although accurate, deterministic models are rather complicated and difficult to use when the configuration of the propagation channel changes. Stochastic models are less sensitive with respect to the configuration of the channel if the distribution of the scatterers and their type do not change dramatically. This paper extends the stochastic, narrow-band log-distance model to ultra-wide band channels. The coefficients of the model are calculated from a set of real data measured onboard a maritime ship. The accuracy of our model is then investigated by comparing the real channel response to the calculated one. Finally, we investigate the channel response to a usual pulse waveform, i.e. the first time-derivative of the Gauss function. The figure of merit to be analyzed is the normalized correlation coefficient or fidelity factor. It should be noted that the dispersion of the measuring antennas was compensated by knowing the gain variation as a function of frequency. This study also leads to minimal values for the time slots between pulses.
Comparative Analysis of Tanker Ships Incidents and their Environment Impacts
Authors: Tromiadis Ramona , Stanca Costel
Published: November 2013

The paper presents a comparative analysis of tanker ships incidents and their environment impacts. The focus is on oil tankers because this type of ships poses the highest environmental risk. By the sheer amount of oil carried, modern oil tankers can be considered a threat to the environment. In case of a maritime accident a ship can suffer fracture of the ships hull that may lead to oil outflow leading to environmental consequences or stability problems, which may again result in capsizing of the vessel. In terms of the consequences for the vessel maritime accidents can be classified in different categories. Severe accident means an accident involving a total loss of the ship, loss of life or severe pollution. Accident that is not severe which may involve: fire, explosion, stranding, collision damage caused by bad weather, damage caused by ice, fracture in the hull or suspected damage to the body. This may also lead to pollution. And incidents that are circumstances or events caused by, or related with the operation of a ship from which the ship or any person is being hazard or results in serious damage to the ship, the ship's structure or the environment. Oil spills have devastating effects on the environment. Shipping regulations have been developed or modified over years on the basis of some significant marine accidents. The regulations are mostly concentrated on reducing the consequences of maritime incidents. Following the Exxon Valdez spill, the United States passed the Oil Pollution Act of 1990 (OPA-90), which excluded single-hull tank vessels of 5,000 gross tons or more from U.S. waters from 2010 onward, apart from those with a double bottom or double sides, which may be permitted to trade to the United States through 2015, depending on their age. Following the sinkings of the Erika (1999) and Prestige (2002), the European Union passed its own stringent anti-pollution packages (known as Erika I, II, and III), which also require all tankers entering its waters to be double-hulled by 2010. Oil tankers are only one source of oil spills. Air pollution from normal tanker engines operation and from cargo fires is another serious concern. Ship fires may not only result in the loss of the ship due to lack of specialized firefighting gear and techniques but the fires sometimes burn for days and require evacuations of nearby residents due to the dangerous smoke.
Studies on the Hydrodynamic Flow through the Cylinder Valve
Authors: Florescu Daniela , Florescu Iulian
Published: November 2013

The paper aims to highlight the pressure and velocity variations on power lines created by water flowing through a cylindrical valve. Drain valve is typical cylindrical bottom of the dam or hydroelectric penstocks. Varieties of dimensions of these valves allow different analyses of the dynamics within them. The valves are able to access water from both sides and different ways of filling and closing action items. This paper presents a method to analyse the influence of parameters on physical-mechanical construction or operation and hence derive dynamic optimal design of these types of valves. Refer to the more intermediate positions of the piston sealing and visualization power lines and areas of turbulence for each position.
Influence of Tool - Semi-Product Friction on the Force Evolution at the Simulation of the Deformation Process with Flat Wedge Tools
Authors: Iacomi Doina , Iordache Monica , Niţu Eduard , Tabacu Stefan
Published: November 2013

Processing through volumetric cold plastic deformation (cold rolling) with flat wedge tools is a procedure used in mass production to process profiles (circular, threads, grooves, teeth) on revolution pieces. Complex profiles obtained by cold plastic deformation with flat wedge tools have important advantages: material economy, high productivity, continuous fibre, superior mechanic properties, low values of the roughness parameters, low costs. In recent years, the simulation of processes of volumetric plastic deformation by the finite element method is used to obtain the optimization of the deformation process and the improvement of the product quality even from the design stage. By numerical simulation there is observed the evolution during the process of different parameters such as: stress and deformations in the deformed body, mode of material flow, final shape and sizes of the product etc. Therefore, it becomes possible to analyse the process even from the design stage by identifying the problems which can appear and their influence on some characteristics of the product obtained: geometry, state of deformations and stress.This paper presents the experimental determination of the deformation force at the processing of complex profiles with flat wedge tools and the influence of the friction coefficient between tool and semi-product on its value; influence established by simulating the deformation process. The process also has been simulated by means of finite element calculations using the Abaqus/Explicit code. The material behaviour is described by using a 5-parameter strain-hardening law and by accounting for thermal effects at high strain-rates. The comparison between the values and the variation of the deformation force recorded experimentally and at simulation allows establishing the optimal value of the friction coefficient and validating the numerical model developed.
Research on Deflection and Cracking of Prestressed Concrete Continuous Girder Bridge
Authors: Guo Fan , Yang Yong Qing , Huang Sheng Qian
Published: November 2013

Through the checking comparison of example bridge, to analysis the major causes of the cracking and too much deflection for prestressed concrete continuous box girder bridge. Calculated weak position and the current presence of cracks in the bridge position basically consistent, so cracks mainly caused by the prestress loss, concrete creep and the temperature effect, the structure stiffness weakened after cracking, then the actual mid-span deflection is greater than the calculated values bound. Therefore, the cracking and too much deflection appear simultaneous and mutual promote. The view that by improving the mechanical behavior of box girders, design parameters optimization, just the fundamental solution to cracking and too much deflection, also, several key issues need study to be addressed.
The Influence of Bridge Construction and Operation on Adjacent Nanjing Yangtze River Tunnels
Authors: Wang Tao , Wang Le , Li Cang Nan
Published: November 2013

With the background of bridge on Riverside Avenue cross over Yangtze River tunnels in Nanjing, studies on the influence of bridge construction and operation on the Yangtze River tunnels are as followed. First, safety control standards of Yangtze River tunnels are presented according to safety situation of the tunnel and the deformation property of super large shield tunnels. Then bridge construction and operation process is simulated to study the engineering influence on adjacent Yangtze River tunnel, to which the excavation of bearing platform foundation pits and piles, and bridge loads are considered. Safety state of Yangtze River tunnel during bridge construction and operation period is estimated based on the safety control standards and numerical simulation results. Construction scheme is optimized, and suggestions are also given to reduce harmful effect on the tunnels brought by construction of the bridge.
Comparison and Analysis on Self-Balanced Method and Anchored Pile Method in Qingdao Gulf Bridge
Authors: He Chun Lin , Gong Cheng Zhong
Published: November 2013

Based on the situ results of Self-balanced Method and Anchored Pile Method on the piles of Qingdao Gulf Bridge, the test method of them have been contrasted in same cite. Compared with anchor piles method the self-balancing test is simple way which saves money and time. And the load-displacement curve obtained from the self-balanced test is closed to anchored pile test; from the view of the sides shear resistance, the side resistance below the load cell in Self-balanced Method is less than the value in Anchored Pile Method while the value under the load cell is more than it. The proportion which tip resistance occupied in self-balancing test is more than the traditional anchor piles method, it should be considered in pile design.
Fatigue Load for Cable-Girder Anchorage Structure of Highway and Light-Railway Cable Stayed Bridge
Authors: Zhao Min , Di Jin
Published: November 2013

Because fatigue load of bridge structure under the highway and light-railway loads has not been specified in current design codes, it is necessary to study the fatigue load of cable-girder anchorage structure of the highway and light-railway cable stayed bridge. Take Chongqin Hongyan Jialing River bridge as the subject of investigation, the fatigue load of cable-girder anchorage structure is computed through MatLab program developed by Monte Carlo method and the rain flow method. According to the traffic flow surveys on the load spectrum, the fatigue load of cable-girder anchorage structure was calculated accurately by the MatLab program. Through comparison with the calculation results of the MatLab program, a fatigue load calculation method used equivalent fatigue vehicle based on the Palmgren-Miner linear cumulative damage theory is reliable and accurate.
Study on Bridge Static Test Based on Close-Range Photogrammetry
Authors: Wang Han Zhang , Tan Shen Zhou , Peng An Quan , Hong Bao Kun
Published: November 2013

Bridge static load test is a conventional method to ensure the safety of bridge, but time-consuming and inconvenient in certain situation to implement. This paper attempts to use photogrammetry method to achieve deformation measurements in the bridge static load test, which is based on time baseline method. using image correlation matching for distance measurement, and using the edge recognition of the targets and ellipse fitting to get the conversion factor of in-image and actual distance. The validation of laboratory experiment and engineering application proved its strong practical value with high accuracy.
Research on Longitudinal Seismic Response of Continuous Welded Rail on Bridge with High-Pier and Long-Span
Authors: Xiao Jie Ling , Wei Xian Kui , Wang Ping , Zhang Meng Nan
Published: November 2013

Longitudinal seismic responses of CWR on bridges with high-piers and long-spans under uniform excitation and traveling wave effect were studied. Results are shown as follows: Under seismic action, rail longitudinal forces near beam joints increase greatly than rail expansion forces (due to beam expansion); Designing CWR on bridges with high-piers and long-spans needs to consider influences of traveling wave effect and wave spreading derection; With the increase of the apparent velocity of seismic waves, rail longitudinal force tends to decrease; We suggest that designing of CWR on bridges crossing high-intensity earthquake zone should consider impact of seismic action, and establish a reasonable check method.
Durability Assessment of Reinforced Concrete Bridge Based on Fuzzy Neural Networks
Authors: Cheng Yong Chun , Guo Hong Bin , Wang Xian Qiang , Jiao Yu Bo
Published: November 2013

In the operation process of bridge structures, some bridges appear early failure without reaching design reference period due to the influences of external environment, vehicle load and other factors. Therefore, the problem of structure durability is very obvious. In this paper, a new durability assessment method is proposed based on fuzzy neural networks, which can take account of the defects and deficiencies of existing durability assessment methods. The simulation for learning and testing samples indicates that the proposed method possesses good learning ability and predictive analysis ability. Actual project verifies the effectiveness of the method
The Fuzzy Reliability Analysis for the Thin-Walled High Pier of SanBei Bridge
Authors: Liu Yun Lai , Bi Wen , Rong Yao
Published: November 2013

The crack control of the thin-walled high pier for SanBei Bridge is effected by various uncertain factors such as loads, concrete strength and the release of hydration heat etc. Because of the fuzziness for the crack control of thin-walled high pier, it is difficult to accurately calculate the crack width to meet with the requirement of the limiting crack design for the structure. Based on the maximal permit crack formula issued in Concrete Design Specifications, the fuzziness analysis is made to the crack control reliability, the index of fuzzy reliable degrees of the girder maximal permit crack width is calculated by Monte Carlo method, and the sensitivity analysis to uncertain parameters is given to provide reference of the design for SanBei Bridge.
The Influence of Calcium Sulfate Whisker on Melting, Crystallization, Rheological Properties and Mechanical Property of Polyamide 1012
Authors: Song Jian Bin , Zhong Yu Mei , Zhang Hui Liang , Yang Wen Bin
Published: November 2013

The effect of calcium sulfate whisker (CaSO4) on mechanical property, melting, crystallization and rheological properties of polyamide 1012 (PA1012) was studied by differential scanning calorimeter (DSC), rheometer and material testing machine. It was shown that CaSO4had no influence on melting temperate of PA1012, but can effectively enhanced nucleation ability of PA1012, which indicated that CaSO4was good nucleation agent for PA1012. The viscosity and storage modulus of PA1012 firstly increased and then decreased as CaSO4content increased. The results showed that CaSO4had little effect on tensile strength, but impact largely flexural strength.
Evulation of Temporary Protection during Bridge Construction against Accelerating Erosion
Authors: Lin Chih Hsien , Cheng Kuei Hsiang , Chao Cheng
Published: November 2013

According to the old bridge damaged emergency conversion program, this study investigates the flow changes during the coexistence of old and new bridge and contraction effect. The flow rate between piers increasing, thereby accelerating erosion. This study uses SMS-2D unsteady flow model to simulate old pier into the pre-construction setting due to their contraction flows and further necessary hydraulic structures and facilities for temporary protection during bridge construction against accelerating erosion for CheCheng Bridge in PenTung country, Taiwan as case study, thus, providing reliable information and references for bridge engineers.
Research on the Application of TLD to Viaduct Box Girder Bridges for Vibration and Noise Reduction
Authors: Yan Xu , Lei Zhen Yu
Published: November 2013

Simulation was conducted to study the feasibility of TLD (tuned liquid damper) on the vibration and noise reduction of rail transit viaduct box girder bridges. The vibration of a 30m span simply supported box girder bridge paved with slab track was modeled in ANSYS. The noise radiation characteristics before and after the installation of TLD were analyzed with Virtual.lab. Results show that TLD can effectively reduce the vibration and noise radiation of rail transit box girder bridges. The vertical displacement peaks of the flange and web can decrease about 40%, while the lateral displacement amplitudes decline by 30%. The lateral noise near webs can reduce 2~3db. The vertical damping property of TLD changes along with the difference of liquid level, and improper use can increase the surface vibration on the contrary. It is suggested that TLD should be used in engineering together with other vibration control measures to reduce the disadvantages.
The Study of Volume Electrical Resistivity and Mechanical Property of CBT/Carbon Black/Aluminum Composites
Authors: Song Jian Bin , Zhong Yu Mei , Lan Lin Sheng , Lin Song Yue , Yang Wen Bin
Published: November 2013

Cyclic Butylene Terephthalate (CBT)/carbon black (CB)/aluminum composites were prepared by melting blend method and their conductivity and mechanical property were studied by Milliohmmeter and material testing machine. The results showed that at below 1.6 wt% of flake aluminum（Al）, volume electrical resistivity and flexural strength of composites increased with Al content increases and reached the maximum value at 1.6 wt% of Al. Composites containing 18.4 wt% of CB and 1.6 wt% of aluminum exhibited excellent comprehensive performance (electrical resistivity, 20.3 Ω.cm; flexural strength, 40.0 MPa).
Analysis of Perpetual Asphalt Pavement Response under Heavy Loads in Northeast Area of China
Authors: Zhou Deng Wen , Wang Rong Jin
Published: November 2013

Severe rutting, cracks and moisture damage are presented on conventional semi-rigid base asphalt pavements not long after completed in China. This phenomenon indicates that conventional philosophy on pavement design could not meet more and more frequent and heavy vehicle. With high structural capacity for high traffic volume and heavy loads, the Perpetual Asphalt Pavements (PAPs) solve those problems well. Meanwhile they need minimal or no major structural rehabilitation and/or reconstruction exercises in their life, which ensures low user-delay. Three PAPs, including semi-rigid base asphalt pavement, flexible base asphalt pavement, and combined base asphalt pavement, are put forward for the northeast area in China considering its climate, traffic characteristic. Finite element method is utilized to analyze response of PAPs under heavy loads. Two key factors, i.e. tensile horizontal strains at the bottom of asphalt layers and compressive vertical strains are investigated. Also the capacities of the structures on bearing overloading are estimated. Four types of wheel and axle, including single axle and single tire, single axle and dual tires, dual axles and dual tires, and tri axles and dual tires are adopted in finite element models. The shapes of tire-pavement contact area are either circular or rectangular to simulate standard load or overloading respectively. When rectangular shapes are adopted, the contact area sizes and the distribution of pressure are varied. Conventional asphalt concrete and high modulus asphalt concrete are adopted. Simulations are done. The competences of the three pavement structures on fulfilling long lives are evaluated.
Structural Mechanics Analysis of Asphalt Pavement Using Large Stone Asphalt Mixture as Base
Authors: Liang Xu , Gu Yin , Wang Jin Chang , Yan Ming Xing , You Si Zeng
Published: November 2013

Asphalt pavement with semi-rigid base is the major structure adopted in the new built highway and municipal roads in China. So as to reduce the unfavorable impact on the rehabilitation of municipal roads which require quick resumption of traffic, better base materials should be adopted. If a pavement base fails, the flexible base, i.e. large stone asphalt mixture (LSAM), should be employed in the pavement rehabilitation practice. Focusing on the practice pavement sections using LSAM as base in Hangzhou municipal roads, the effect factors of subgrade modulus, base modulus and base thickness on surface deflection and bending strain in base bottom is analyzed. That work is done through finite element method of software BISAR3.0. The results provide a practice reference for municipal roads rehabilitation needing to open traffic early.
Comprehensive Evaluation of Bolt and Wire Mesh Support Scheme of Roadway Based on Set Pair Analysis
Authors: Jiao Shen Hua , Wang Jin An , Zhou Hao Liang
Published: November 2013

Set pair analysis is a combination of qualitative and quantitative methods used in decision-making. Aiming at the irrelevance of each indicator, an evaluation model of bolt and wire mesh support scheme of roadway based on set pair analysis is set up and a relativity to optimal scheme which combines multiple indicators as well as its set pair situation are applied to describe the comprehensive benefits of bolt and wire mesh support scheme. Evaluation results of three optional support schemes in a mine of Yaojie Coal and Electricity Co., Ltd are obtained using this method, and an optimal scheme with the best comprehensive benefits is determined.
The Performance Evaluation and Application of Recycled Concrete in Constructions
Authors: Zhao Chao , Wang Jun
Published: November 2013

In recent years, with the urbanization in our country speeding up, the phenomena of wasting concrete due to the demolition and renovation are very common. For our country, resources are very scarce. How to reuse the waste concrete, so as to keep the sustainable utilization of building resources, is a topic worthy of deep thinking. In order to realize the full use of recycled concrete, this paper points out that the use of recycled concrete is the key to keep the sustainable utilization of natural resources. Based on this, it discusses the work performance, mechanical properties, durability properties, shear properties, seismic performance of recycled concrete and its performance evaluation.
Analysis of Heat Conduction Mechanism on Tympanites Roadbed
Authors: Yuan Jian Yi , Cheng Jian Hua , Wang Chun Feng , Zhang Ding Bang , Wu Zhen Hua
Published: November 2013

In order to reveal the heat conduction direction on roadbed, a series of theoretical analysis and mathematical derivations are used. Through simplifying the frozen soil layer as an equivalent homogeneous frozen body, the physical model of heat conduction was founded. Also, applying the entropy change of the thermodynamics second law, the direction of the actual heat transfer was analyzed. Further more, the three-dimensional and two-dimensional differential equation of unsteady heat transfer in Cartesian model were obtained by using Fourier's Law and importing the micro unit. It has significant senses for deep research of roadbed tympanites.
Clastic Rock Physical Characteristics of Southern Songliao Basin Shiwu Fault Depression Layer
Authors: Zhang Yun Feng , Zhao Hui , Yuan Hong Qi , Gao Zeng Hui
Published: November 2013

We sum up the reservoir space types and characteristics of clastic rock reservoir ShiWu fault depression rift layer study area, through core observation, microscope, scanning electron microscope and mercury injection methods, and discuss the development characteristics and formation mechanism of pore and fracture. A large number of core analysis, drill results and test mining research has confirmed that the study area is constructed by the strong force, the micro-cracks are well developed, it is not only important reservoir space, but also the flow of oil and gas wells to obtain high yield important seepage paths, is to obtain yield the necessary conditions.
Field Measurement and Analysis of Vibration Response in the Metro Shield Tunnel with Straight Joint
Authors: Li Ming Yu , Guo Yuan Cheng
Published: November 2013

Appling the M8 as the monitor objects and choosing the single-round shield tunnel with or without the steel spring floating slab and the DOT shield tunnel with straight joint as the research objects, the vertical vibration response of the track bed and the standard block in different conditions was compared. The peak vibration acceleration of two measuring points and vibration response time of the standard block in the DOT is smaller compared with the DOT and the single-round shield tunnel when a single train is through the monitoring section. Vibration response time and intensity of the DOT structure is increasing with two trains intersection. Compared to the other two shield tunnels, structural vibration response of the single-round shield tunnel is significantly decreased by the isolation effect of steel spring floating slab. For the vibration acceleration of the track bed and the standard block in the three types of shield tunnels, spectrum range is 0Hz~150Hz, and peak acceleration is in the same frequency range, which is 35Hz~70Hz. Peak vibration acceleration of the track bed is greater than that of the standard block.
Study of Tunnel Water Detection through Infrared Acquisition Technology Based on 3D Trend Analysis
Authors: Zhang Shu Hao , Wang Ya Wei
Published: November 2013

The study discusses a revised method of water detection through infrared acquisition technology. In the case of Xianghe tunnel construction, the authors built 3D infrared radiation field functions through 3D trend analysis. The separately calculated radiation intensity trend values and outliers were processed by the visualization software, Voxler, and transformed into 3D distribution graphs for further comparison and analysis. The result indicates that the technique and method applied in this article successfully eliminate the random interference and realize the detection of aquifer.
A Study on Optimization of Middle Vent Shaft in Subway Tunnel Ventilation System
Authors: Lin Fang , Zeng Yan Hua , Zhou Xiao Han , He Jian Feng
Published: November 2013

The air flow and temperature variation in the subway tunnel are different in the railway tunnel. Its necessary to study the middle vent shaft in subway tunnel ventilation system. According to the primary design documents of one subway line in Chengdu, the paper sets up the metros geometric model which is used in the SES program and also does the simulation analysis of the biggest transportation capacity in the line. The simulation mainly analyzes the adoption of the middle vent shaft which is located in the running tunnel between the station A and B. Meanwhile it also analyzes the influence of middle vent shaft on the nearby piston vent shaft, the wall surface temperature and the air temperature in the tunnel. Finally it takes temperature as the estimated index, analyzes the advantages and disadvantages of the middle vent shaft and makes the theoretic accounts for the design. The comprehensive analysis is that this middle vent shaft could be canceled.
Application of Infrared Method for Water Detection in Karst Tunnel
Authors: Guo Xin Ming , Cui Ge , Fu Ya Peng , Fang Yong
Published: November 2013

Water rush and mud rush are two major problems during the process of tunnel construction, which can lead to big troubles. Advanced geological prediction should be carried out to prevent the emergency of water rush and mud rush during the construction in the karst and water-rich areas. Infrared detection technology is a way to detect the hidden water. In this paper, basic principles of model HY-304 infrared detection meter are described, and it is applied in Shuangbei Tunnel. By analyzing the predicted results and comparing it with the situation of excavation, the instrument is feasible as to water rush in karst areas and infrared detection technology has a great opportunity to be applied in the tunnel engineering under complex geological conditions.
Introduction of Construction Process in Shenjiamen Immerse Tube Tunnel and Problem Analysis of Grouting
Authors: Wei Gang , Qiu Hui Jie , Wei Xin Jiang
Published: November 2013

The construction method for immerse tube tunnelling varies significantly in sites with different hydrogeological conditions. Using the construction process of the undersea immerse tunnel at Shenjiamen harbour, Zhoushan city, Zhejiang Province as an example, the overall construction process of undocking, float transporting, immerse positioning, locking, grouting and backfilling were introduced in this study, with possible problems at each stage listed in details. The problems occurred when grouting Tube E1, E2 and E3 (floating or settling) and relevant solutions were concluded and the related possible causes were analysed.
The Effect of External Conditions on Ignition Temperature of Thermoplastic Polyurethane Elastomers
Authors: Turekova Ivana , Szabova Zuzana , Chrebet Tomas , Harangozo Jozef
Published: November 2013

The paper reports a study of the impact of moisture and age of pellets, as well as an external condition, on the thermal degradation of the thermoplastic polyurethane elastomers. Because thermoplastic polyurethane elastomers are hydroscopic polymer, moisture will have a significant impact on thermal degradation. For determination of the effect of moisture and age were used the thermo gravimetric analysis, differential scanning calorimeter and ISO STN 871: Plastics. Determination of ignition temperature using a hot-air furnace.
The Grouting Technology of Large-Section Highway Tunnel in Water-Rich Karst Formations
Authors: Zhou Chao Yue , Fang Yong , Fu Ya Peng , Cui Ge
Published: November 2013

It is a challenge to deal with karst in the construction of large cross-section tunnel. Under the background of Shuangbei Highway Tunnel, a new kind of grouting technology is introduced. According to hydrogeology, field tests are carried out to select grouting materials and proportion of mixture. Combined with the project practice, grouting construction technology is discussed such as grouting equipments, grouting parameters, operation technique, grouting ending standards. It has been proved that the technology is effective in tunnel construction.
Application of Bayesian Network in Safety Evaluation of Metro Construction
Authors: Liu Xiang Ke , Wang Zhi Shen , Wang Hai Liang , Wang Jun Tao
Published: November 2013

The paper introduced the Bayesian networks briefly and discussed the algorithm of transforming fault tree into Bayesian networks at first, then regarded the structures impaired caused by tunnel blasting construction as a example, introduced the built and calculated method of the Bayesian networks by matlab. Then assumed the probabilities of essential events, calculated the probability of top event and the posterior probability of each essential events by the Bayesian networks. After that the paper contrast the characteristics of fault tree analysis and the Bayesian networks, Identified that the Bayesian networks is better than fault tree analysis in safety evaluation in some case, and provided a valid way to assess risk in metro construction.
Finite Element Analysis on Seismic Behavior of Typical Residence in Yunnan
Authors: Wang Dan , Tao Zhong , Li Ling Xu
Published: November 2013

Based on the actual inspection to typical Stilt timberwork residence in Puer of Yunnan.This paper find that many places still inadequate, of which the most outstanding part were lack of plinth , the defects of support in the node , the lack of beams and columns ,etc. A contrast analysis of maximum sheers in every storeys and storey drift are made between unreinforced and reinforced slopes by using the finite element software of etabs , which verified the rationality of the strengthening scheme.
Assessment Model Research of Seismic Damage for Clear Water Tanks in Water Supply System
Authors: Gao Lin , Guo En Dong , Liu Zhi
Published: November 2013

In order to study the damage characteristics and seismic performances of clear water tanks in water supply system, common damage types and main influence factors are summarized based on the collected damage data, and seismic vulnerability matrix is obtained. Seismic damage loss ratio is suggested by combination damage and construction cost. On the strength of the above results, assessment models of seismic loss for clear water tanks are built, including group assessment model and monomer assessment model. The accuracy and applicability of the models can meet engineering requirements. Finally, anti-seismic suggestions and countermeasures of pools are given based on the above research results.
Research on Seismic Disaster and Prevention Countermeasures of Electric Power System
Authors: Yu Wen , Zhou Yi Hang , Zhu Li Xin , Ge Xue Li
Published: November 2013

Electric power system is an important part of lifeline systems, and it is vulnerable to earthquake. In this paper, the characteristics of failure of electric power system are summarized on the basis of its damages in past earthquakes. Then earthquake damage and failure mechanism of electric structure and equipment are analyzed. Finally, from the aspects of engineering and non-engineering, disaster prevention countermeasures are presented.
The Application of Peak Number Attribute in the Prediction of River Sand
Authors: Li Ting Ting , Zhang Xing Xing , Ma Shi Zhong , Wang Zhao
Published: November 2013

Its a commonly used method to predict layer by using seismic attributes, especially for some of the less well control channel sand bodies whose role is more important. Putaohua reservoir in Gaotaizi oilfield mainly develop shallow water delta front subaqueous distributary channel sand bodies which has narrow rivers and thin sand bodies, meanwhile, the existing well density is difficult to control the trend and boundary of the channel. By using seismic forward modeling analysis techniques, this paper researched the differences of seismic reflection characteristics among different geological model of channel sand bodies, then , further pointed out the methods of channel sand prediction by using the peak number attribute and analyzed the predictive effect. The results show that this method can effectively improve the prediction accuracy of thin interbedded reservoir.
Study on Risk Analysis of Seismic Secondary Fires Disaster in Villages and Small Towns
Authors: Chu Jian Yu , Chen Ling Li
Published: November 2013

Compared with the cities, Chinese villages and small towns have many problems, so the threat of seismic secondary fires disaster is larger than that of the cities. The characteristics of seismic secondary fires disaster in villages and small towns are fire sources great and fire spreading rapidly. Based on the present situation in China, this paper gives seismic secondary fires disaster chain of evolutionary flow. Combined with single house fire and fire spreading in region, it puts forward the risk analysis model.
Classification and Rapid Assessment of Subgrade Seismic Damage after Earthquake
Authors: Cong Li , Chai He Jun , Tang Sheng Chuan
Published: November 2013

As an important part of earthquake disaster relief, highway traffic system is the passage for rescue staffs, material transport and evacuation. Hence, people are concerned about destruction condition and safety of highways after earthquakes. However, there are neither systematically scientific methods to classify highway subgrade seismic damage, nor systematic study on its rapid evaluation methods. Therefore, the Paper studies post-seismic highway subgrade damage grade and rapid evaluation methods, to be as a significant reference for improving post-seismic emergency rescue and relief efficiency, as well as for recovering and reconstructing highway traffic system.
Research of Seepage Influence on the Lateral Water-Earth Pressure in Underground Structures
Authors: Kui Dai
Published: November 2013

Earth pressure field and hydrostatic water pressure field are usually considered for classical earth pressure theories. Nonconsideration of groundwater seepage field is one of the main reasons why measured values of water-earth pressure on supporting structures are generally very different from those calculated values.Under the action of seepage,seepage force changes soil effective stress and affects soil shear strength.Through calculating the interraction of the hindering force field and seepage force field,a multi-field coupling problem is solved, a new calculation expressions on the foundation pit is presented.Key words : multi-field coupling; seepage ; lateral pressure ; water-earth pressure ; hindering force
Mechanism of Lake Area Variations and Water Level Changes in Nam Co Lake
Authors: Du Yan , Xie Mo Wen , Hu Man
Published: November 2013

The Tibetan Plateau is one of the best areas for the study because of its geographical location as well as human disturbance. AS one of the largest lakes in the Qinghai-Tibet Plateau, Nam Co Lake seepage underestimated for a long time. By linear regression analysis of hydrological data from 1970-2005, we qualitatively understands the water level operation mechanism. The result shows that the model deviates from 2000, compared with the actual water level. Correlation analysis indicates the Nam Co Lake seepage flow reduces after 2000. The Three Gorges project resulted in the uplift of the downstream water level, which exacerbates the rise of water level of Nam Co Lake. Owing to the non timeliness of underground seepage recharge, water level of downstream lake is difficult to simulate. According to the result and recent research, underground seepage may be a cycle, affecting the water level of all the lakes.
Research on Key Algorithms for Seepage Analysis Using Composite Element Containing Drainage Holes
Authors: Xu Gui Sheng , Guo Jian Qiang
Published: November 2013

For seepage analysis using Composite Element Method(CEM), the drainage holes are treated as “air sub-elements” with high permeability contained in the conventional rock(soil) element, which is called “composite element”. To ensure the validity and correctness of the calculated results, the “permeability coefficient” of drainage holes and transmissibility coefficient of the interface between rock(soil) and drainage holes are studied and some reasonable suggestions are given. To improve the calculation precision and efficiency of CEM, the p-version adaptive method is studied and the corresponding algorithm of upgrade the hierarchical order and accelerating convergence are implemented in the CEM.
Polymer Cut-Off Wall Quality Testing Based on Direct Current Response Measuring
Authors: Lou Xuan , Wang Rui , Zhou Yang
Published: November 2013

Polymer Cut-off wall is a new kind of anti-seepage work used in hydraulic and civil engineering. It is quite different from concrete cut-off wall in materials and sizes. Traditional quality testing methods such as elastic wave tomography, GPR and resistivity imaging are all not applicable in polymer cut-off wall quality testing. We design a new testing method based on DC potential measuring. We use electrodes to build underground electric field and measuring the change of potential near the wall to analysis the integrity of the wall. We finish a series of indoor model and some full-scale tests. The results prove that the method is effective and practicable in polymer cut-off wall quality testing.
Dynamic Structural Analysis of Large Dams by Fourier SEM
Authors: Tan Ping , Li Nan Sheng , Jiang Qun
Published: November 2013

Spectral element method (SEM), which combines the ideas of the finite element method (FEM) with the theory of spectral method, is being in the initial stage of developing for the static and dynamic analysis of large dams. The best advantage of SEM is that it can arrive at so-called spectral accuracy out of FEMs reach. In this paper, the Fourier SEM has been first used in dynamic analysis of large dams in order to improve the accuracy and efficiency of numerical results and procedure. The study begins with the governing equation of motion of large dams, then deduces the corresponding SEM stiffness, mass (damping) matrix and equivalent load vector taking advantage of the Fourier interpolation polynomials to approximate the unknowns in spatial domains. This paper also reveals the valuable application of SEM in complicated structural engineering. The formulation proposed in this paper can also be applied to the general dynamic analysis of physical structures.
Determining the Flood Control Level of Small Reservoirs with Fuzzy Decision by Stages
Authors: Liu Zhi Qi , Lu Jin Xi , Jiao Jian , Zhang Qing
Published: November 2013

The limited water level of reservoir by stage, fully consider the seasonal variations of the average annual precipitation characteristics in every reservoirs control catchment. Its not only ensuring the rational use of water resources, increasing economic and social benefits to the reservoir, but also ensuring the safety of flood control reservoir flood season, to protect people's lives and property. Determine flood limit level for small reservoir by installments should consider the balance between the economic benefits from improving the water level and the consumption of human and financial resources caused by the installments flood water level adjustment. At the same time, the water resources should be intelligent used in order to let the level of reservoir get in normal. This paper, according to the characteristics of small reservoir, calculated on the reservoir storage capacity can be increased basis of the existing flood control capacity through calculating the value of membership function during reservoir flood season. So that the new limited water level can be obtained after calculating the reservoir capacity increase according to the capacity-water level graph.
Study for Regional Evapotranspiration by Fuzzy Inference System
Authors: Lin Chih Hsien , Chao Cheng , Cheng Kuei Hsiang
Published: November 2013

This paper demonstrates the application of fuzzy inference system (FIS) employed by mapping meteorological data between known inputs (wind speed, relative humidity, temperature, and sunshine radiation) and output (evapotranspiration). The results after training show that the FIS is able to capture the nonlinear feature for evapotranspiration. Moreover, the trained FIS is integrated into geographical statistical technology for the estimation of the regional evapotranspiration, forest and farmland in Dan-Shui Basin as an example. It is found that FIS simulation effectively reduces the amounts of formula parameters, computation time, and diverse procedure, which it can be another efficient mathematical tool to deal with the study of evapotranspiration estimation.