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20 January 2017, Volume 36 Issue 1 Previous Issue    Next Issue
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Bridge & Tunnel Engineering
Highway & Railway Engineering
Port & Waterway · Hydraulic & Hydroelectric · Resources & Environment
Traffic & Transportation Engineering
Vehicle &Electromechanical Engineering


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Bridge & Tunnel Engineering

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Analysis of Temperature Effect on Cable-Stayed Self-Anchored Suspension Composed Model Bridge with Three Towers CAI Junzhe1，SI Long2 2017, 36(1): 1-8.  DOI: 10.3969/j.issn.1674-0696.2017.01.01 Abstract ( )   PDF (1232KB) ( )   In order to study the mechanical performance of the cable-stayed self-anchored suspension composed bridge with three towers under temperature effect, a model bridge with 1∶20 reduced scale was made, and it's deformation performances were studied under four conditions, which were uniform temperature change, temperature difference between cables and girder, sunshine temperature difference on tower and sunshine temperature difference on girder. The results show that there are the same change trends of adjacent hanger tension in suspension section, one hanger tension increase and another descend, which has greatly influenced the uniform distribution of hanger tension. Under the condition of temperature difference between stayed cables and girder, the degree of the girder deformation changes and of the tensions changes of short stayed cable are probably significant. References | Related Articles | Metrics

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Anchoring Surface Displacement Monitoring System Based on Differential Amplification Method LAN Zhangli1，TIAN Yuan1，ZHOU Jianting2，YAO Jinqiang1 2017, 36(1): 9-13.  DOI: 10.3969/j.issn.1674-0696.2017.01.02 Abstract ( )   PDF (1031KB) ( )   A measurement system based on the piston device displacement differential amplification method is put forward for monitoring the displacement of anchorage surface through research on the characteristics of anchorage plane of the suspension bridge, design of a differential amplifier device in combination with image processing technology. The composition and measurement principle of the system were introduced, and the creep data of the anchor surface was obtained by the image segmentation and the circle fitting method and the displacement transformation. About the measuring system, lens distortion error and non vertical installation errors were analyzed and the solutions were expounded. The experimental results show that when the creep range of -1.2 cm～+1.2 cm, the measurement error can be controlled within 3.5%. References | Related Articles | Metrics

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Tests on the Features of Elastic Wave Velocity in Bridge Grouting Tunnel WEI Lianyu, WANG Jinwei, LIU Yongping, ZHANG Guopan 2017, 36(1): 14-18.  DOI: 10.3969/j.issn.1674-0696.2017.01.03 Abstract ( )   PDF (940KB) ( )   This paper checked prefabricated box beam grouting tunnels with JL-BPAC(A) in the actual project. The normal distribution of the original data was checked by using the χ2 method, and the result consistency was verified. The results indicate that the impact elastic wave in normal grout duct propagates the rule of normal distribution. The mathematical average value in the tests can be used as an overall mathematical expectation for all the samples, thus disclosing the propagation characteristics of impact elastic wave in grout duct meanwhile showing the normal construction of current duct grouting. The method of improving the completeness of the tunnel grouting is raised. References | Related Articles | Metrics

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Dynamic Response Analysis of Local Subway Tunnel under Spatially Varying Earthquake YAO Erlei, MIAO Yu, CHEN Chao 2017, 36(1): 19-23.  DOI: 10.3969/j.issn.1674-0696.2017.01.04 Abstract ( )   PDF (2828KB) ( )   Subway tunnels are extremely long linear structures, on which the spatial variance of earthquake can exert significant influence. Considering the local site response and incoherence effect, the artificial earthquake ground motions were generated by using the improved spectral representation method. Through finite element method, the dynamic responses of local bending and straight subway tunnel across different sites to spatially varying earthquake were studied. The Numerical results show that at the boundary between different sites, the tunnel displacement sharply changed. The section moment of bending tunnel was higher than that of straight tunnel, while the shear force of bending tunnel was smaller than that of straight tunnel at the interface between different sites. Tunnel stress mainly concentrates on the interface between different sites and the angle between tensile-compressive area and tunnel axis is about 45 degree. References | Related Articles | Metrics

Highway & Railway Engineering

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Silica Fume's Impact on the Interface Bond Strength of Steel Fiber-cement Matrix MEI Yingjun1，WANG Zhaobing2，DAI Chao3 2017, 36(1): 24-29.  DOI: 10.3969/j.issn.1674-0696.2017.01.05 Abstract ( )   PDF (2285KB) ( )   Tests of steel fiber pulled out from cement matrix were carried out by self-made mould and the pull out load-displacement curve of common concrete and silica fume reinforced steel fiber concrete are achieved. The content of steel fiber was 0～1.2% by volume fraction and the content of silica fume is 0～12% by quality replacement of cement. The micro-hardness and micro-morphology of the interface between steel fiber-cement matrixes are obtained by micro-hardness test and SEM test. Based on the above experiments, the concept of interface bond pull out toughness was put forward, and the interfacial bond strength and toughness of steel fiber pulled out from cement matrix were calculated and the law of silica fume's impact on the interfacial bond strength, steel fiber pull out toughness, micro-hardness and microstructure of the interface were analyzed. The results of tests show that the interfacial bond strength of steel fiber-cement matrix in steel fiber reinforced concrete is increased by 10.7%～44.2% with the content of 3%～12% silica fumes. The micro-hardness of the interface region is increased by 7.4%～38.8%，and the distance 60 μm, in ordinary concrete, between the weakest layer of the interface and the surface of the steel fiber is reduced to 40 nm after the addition of 12% silica fume, and the greater addition of silica fume, the better effect is shown. With the different additions of silica fume, the displacement of steel fiber under peak loads at time of being pulling out is reduced by 4.1%～25.9%. As for steel fiber reinforced concrete with different content of fiber, the ideal content of silica fume is 6%～9% for the steel fiber's pull out roughness. References | Related Articles | Metrics

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Performance and Mechanism Investigation of Recycled Plastic Modified Asphalts YANG Xiwu, LIU Ke, FENG Mei, HE Ze 2017, 36(1): 30-35.  DOI: 10.3969/j.issn.1674-0696.2017.01.06 Abstract ( )   PDF (2032KB) ( )   The method of cracking polyethylene （PE） and polypropylene （PP） was introduced. Two kinds matrix asphalts—Maoming-90 and CNOOC-70—were chosen, and blended with cracking recycled plastics（CRP） or non-cracking recycled plastics（RP） by mass of 6% and 8% respectively. Three indexes （penetration, soften point and ductility）, storage stability, low-temperature bending property, viscosity and aging performances of the modified asphalts mixed with cracking recycled plastics were compared and studied. The component variation of RP and CRP, and the components variation of the asphalts with or without modifier were test analyzed with infrared spectrum. The modified asphalt mechanism was analyzed. Test results show that the high-temperature property of all kinds CRP modified asphalts increase greatly, the soften point of CNOOC-70 asphalt with CRP modifier addition of 6% can grow from 48.7℃ to more than 70℃，and demonstrate sound storage stability without segregation and meanwhile demonstrate their low-temperature bending property, viscosity and aging performances similar to that of matrix asphalt. References | Related Articles | Metrics

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Estimation of Fatigue Failure of Asphalt Concrete Based on Three-Parameter Weibull Distribution LI Xiao1，2，LIANG Naixing2，CHENG Zhihao1 2017, 36(1): 36-41.  DOI: 10.3969/j.issn.1674-0696.2017.01.07 Abstract ( )   PDF (1098KB) ( )   Weibull distribution is widely used in asphalt mixes fatigue failure fitting. Compared with two-parameter Weibull distribution, three-parameter Weibull distribution shows better practicability in the situation that fatigue failure does not exist at initial steps. Through indirect tension test （IDT） at different stress levels and different temperatures, the fatigue behavior of three different asphalt concrete were analyzed with location parameter using iterative computations of scale parameter, shape parameter. Combined with test data, the distribution function was calculated based on three characteristic parameters. The results show more reasonable fitting accuracy of three-parameter Weibull distribution than its calculated results by others methods. The fatigue curves and fatigue equations at different test conditions of 50% reliability are obtained. References | Related Articles | Metrics

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The Study on the Interfacial Viscoelasticity and Zeta Potential of Emulsified Asphalt PEI Qiang, DU Sujun, PANG Jinyu 2017, 36(1): 42-45.  DOI: 10.3969/j.issn.1674-0696.2017.01.08 Abstract ( )   PDF (886KB) ( )   The relationship among interfacial dilatational modulus, zeta potential and the stability of emulsified asphalt was investigated by measuring interfacial dilatational modulus and zeta potential of self-made emulsifier A and B. When the concentration of self-made emulsifier A and B was 100 mg/L and 50 mg/L respectively, the elasticity of interfacial film was the largest. When the dosage of emulsifier A and B was 2.8% and 1.2% respectively, the emulsified asphalt presented the maximum Zeta potential absolute value and the best storage stability. Thus, the interfacial dilatational modulus and zeta potential has a good correspondence to the storage stability of emulsified asphalt, so both can be used as an indicators of evaluation of the emulsifier merits and determination of emulsifier optimal dosage. References | Related Articles | Metrics

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Comparison of 2PB and 4PB Beam Fatigue Test Methods of HMA LI Benliang1，HUANG Weidong1，MENG Huilin2，MA Huabao2 2017, 36(1): 46-51.  DOI: 10.3969/j.issn.1674-0696.2017.01.09 Abstract ( )   PDF (4477KB) ( )   Beam fatigue tests are commonly used to evaluate the fatigue characteristic of asphalt mixture around the world.2PB is widely used in Europe while more application of 4PB is found in USA. The two test methods are compared in test standards, specimen requirement, specimen aging condition, test conduction and application of test results. The conclusions are drawn that: 2PB is more complex in specimen preparation, demands more accurate geometry and more sophisticated test equipment, but the specimen is more homogeneity and representativeness than 4PB. Specimen cluing, fixing and replacing during the test is more time-consuming in 2PB test, making the test operation more complicated, also the maximum loading strain is no more than 500με in 2PB test. In contrast the specimen fixing and replacing, loading strain adjustment can be achieved by software controlling in 4PB test, making 4PB test an easy operation, also the maximum loading strain can be about 2 000με. More specimens are required to obtain a fatigue curve of in 2PB than that in 4PB, time-consuming in 2PB is more than double of that in 4PB. Fatigue life of 2PB test can be regarded as real fatigue of pavement in situ because of the observed cracks cross specimen after test but the fatigue life of 4PB test is conservative. Fatigue life variation of 2PB is smaller than 4PB. Test results of 2PB can be used for comparison as well as an input parameter in pavement design, results of 4PB can be only used for HMA comparison. References | Related Articles | Metrics

Port & Waterway · Hydraulic & Hydroelectric · Resources & Environment

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Stability Analysis and Evaluation of Soil Slope System Considering the Shear Dilatancy Effect CHEN Xi1，ZHANG Xunwei1，2，MIAO Jianglong1，WANG Dongyong1 2017, 36(1): 52-57.  DOI: 10.3969/j.issn.1674-0696.2017.01.10 Abstract ( )   PDF (1748KB) ( )   Based on numerical calculation examples the influence of soil expansion on earth side slope and the stability of side slope system was studied and two different views regarding dilatancy impact on slope stability were compared and these two different methods of finite element strength reduction and gravity loading method were tested and verified. The test results show that the finite element strength reduction method has its limit in stability analysis of side slope of non-associated platic earth nature and was only effective when statisfying the dilation angle less than internal friction angle in course of redcution. In addition, study was carried out regarding the view which stated that it is a safe method to take approximate dilation angle 0°. After study made on the side slope strengthened with anti-slide pile it was found that the less is the dilation angle, the less is the deflection of anti-slide pile and the maximum earth pressure acting on the pile shaft, which presented the characteristics that earth flow through pile body more easily. Hence considering from the respect of side slope safety factor, the minimum safety factor can be obtained by taking dilation angle approximately 0° , which is a safe practice. But considering from aspect of design of anti-slide pile this method is not safe. It is hence suggested that the value setting of dilation angle shall be reasonably considered by specific issue analysis according to specific conditions of slope. References | Related Articles | Metrics

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Seismic Fuzzy Reliability Analysis of Bedding Slope Based on the Maximum Entropy Principle GONG Wenhui, ZHONG Xuhan, CHEN Xunlong, QIU Jinwei, LI Yi 2017, 36(1): 58-63.  DOI: 10.3969/j.issn.1674-0696.2017.01.11 Abstract ( )   PDF (920KB) ( )   The maximum entropy method was applied to calculating the seismic fuzzy reliability of bedding slope with the seismic action and the fuzziness of slope instability considered. By pseudo-static method, the seismic load was simplified into horizontal and vertical inertial force and the fuzzy limit state equation was established with the fuzziness of the limit states considered. The maximum entropy principle was applied to estimate the probability density distribution which was closest to reality and the higher order moments of the random variable information were fully used to calculate the fuzzy failure probability of bedding rock slope under seismic load. An example was analyzed and the fuzzy failure probability was calculated. The results from a case study indicate that the method with a fast convergence and a high calculation efficiency which more complies with engineering practice can be widely used in fuzzy reliability analysis of practical engineering. References | Related Articles | Metrics

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Study on Failure Criterion of Coarse-Grained Soil inThree-Dimensional Stress State SHI Weicheng1，ZHU Jungao2，DAI Guozhong1，SHI Guicai1，ZHU Jianqun1 2017, 36(1): 64-67.  DOI: 10.3969/j.issn.1674-0696.2017.01.12 Abstract ( )   PDF (1470KB) ( )   Mohr-Coulomb criterion and the failure criterion of coarse-grained soil were expressed by p, q and b. The failure lines on π-plane of the two criterion were compared with the test results of coarse-grained soil in which both p and b kept constant. It is shown that the later criterion is closer to the test results owing to considering the influence of the intermediate principal stress ratio b. Both of the two criterion have singular points which are disadvantageous to numerical calculations. Based on the experimental results of loose sand, dense sand, gravel and coarse-grained soil, a new strength criterion is proposed whose failure line on π-plane fits for the test results. References | Related Articles | Metrics

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Study on the Relationship between the Impervious Surface and the Urban Thermal Environment in Chongqing Based on Landsat8 OLI/TIRS Image DENG Rui1，2，HU Richa1，LIU Liang1，WANG Xiaoting1 2017, 36(1): 68-76.  DOI: 10.3969/j.issn.1674-0696.2017.01.13 Abstract ( )   PDF (7694KB) ( )   In this paper, On in combinatiom with remote sensing methods and GIS technology and used the Carlson methods Jiménez-Muoz split window algorithms wasused to extract impervious surface and inverse surface temperature based on Landsat-8 image data in 2014. Then analyzed the distribution pattern of impervious surface and thermal island and the correlation of them was analyzed to study the relationship between impervious surface and heat island effect on the main city of Chongqing. The results show that the impervious surface area and the heat island in main city of Chongqing? are more concentrated and mostly in built-up areas. Impervious surface and surface temperature has a positive correlation and it has a significant effect on the urban heat island. References | Related Articles | Metrics

Traffic & Transportation Engineering

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Study of Driver's Fatigue Level Grading Experiment Based on His Physiological Signal LU Zhangping1，YIN Chuanbin1，LI Rui1，HE Ren2 2017, 36(1): 77-81.  DOI: 10.3969/j.issn.1674-0696.2017.01.14 Abstract ( )   PDF (977KB) ( )   With the help of Electroencephalogram （EEG） and Electrocardiogram （ECG）, a real traffic driving experiment which combining physiology test and subjective fatigue survey was conducted to study the law of fatigue level variation of a diver who was driving during 09：00—12：00AM，12：00—14：00PM and 21：00—23：00PM. By the principal component analysis （PCA）, this study was able to establish the relationship between EEG and ECG signal, and to set up a comprehensive indicator to determine driver fatigue. The results show that the above-mentioned comprehensive indicator can recognize different levels of driver fatigue and the fusion of different indicators thas can improve the accuracy in detecting driver′s different fatigue levels. References | Related Articles | Metrics

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Analysis of Wide Range Population Flow Analysis Based on Mobile Phone Signaling TANG Xiaoyong1，ZHOU Tao2，LU Baichuan1 2017, 36(1): 82-87.  DOI: 10.3969/j.issn.1674-0696.2017.01.15 Abstract ( )   PDF (1915KB) ( )   With the cell phone data from mobile communication system, after a series of technical methods processing such as base station positioning, data filtration, travel behavior recognition and sample expansion, the distributions of resident population and employment, OD matrix between large zones can be acquired. This method has obvious advantages of low cost, wide coverage, large sample, continuous observation, and can be used as a new means for data collection in urban planning. In Chongqing Urban-Rural Master Planning （2007—2020）, the population exchange within Chongqing was analyzed based on the CQ Unicom mobile signaling data, and quantitatively evaluated the connection degree between counties. The result was used for aligning each county's development strategy and as a basis for passenger demand forecasting for rail or expressway network layout planning. References | Related Articles | Metrics

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A Broadcasting Policy of Emergency Warning Message in Vehicular Ad-hoc Network CAO Wenjing, XU Shenghong 2017, 36(1): 88-92.  DOI: 10.3969/j.issn.1674-0696.2017.01.16 Abstract ( )   PDF (876KB) ( )   Vehicle safety can be improved by communicating alarming messages in vehicular ad hoc network. High reliability and real-timeliness of warning messages transmission is required. Currently , the reliability of emergency messages transmission is guaranteed by repeated broadcast without calculating method for the message repeating rate. In current research, broadcast repeating rate per second was not discussed herein. A vehicular speed-based broadcast repeating ratio model is proposed based on the thought regarding warning information generation and the broadcasting system as a queuing system and by establishing a model on the relationship between vehicular speed and alarming information . The delayed transmission of the alarming information was limited and an calculation formula was worked out for calculation of optimized rate of repeated alarming. Experiment results showed that the method better strikes the balance between the reliability and real-timeliness of alarming information transmission by broadcast and the operation is easy. References | Related Articles | Metrics

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Traffic Impact Fee Allocation of Construction Project Based on Improved Shapley Value Method YAN Dongmei1，FENG Shumin2，SHAO Yiming3 2017, 36(1): 93-96.  DOI: 10.3969/j.issn.1674-0696.2017.01.17 Abstract ( )   PDF (852KB) ( )   The trafic impact factors were determined by analyzing the influences on traffic fee allocation, by Shapley value method and by considering such influences as traffic operation, traffic organization and traffic safety. The hierarchy analysis method was used to calculate weights of each of the various influencing factors. The traffic fee allocation model was established by means of improved Shapley value method. Finally three enterprises of certain one area were taken as examples to make reasonable allocation of traffic impact fees among the three enterprises. The results show that this model is easy and operable in some degree. References | Related Articles | Metrics

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Research on the Optimization Model of Site Selection and Layout of Logistics Distribution Center LI Ming，LIU Hang，ZHANG Xiaojian 2017, 36(1): 97-102.  DOI: 10.3969/j.issn.1674-0696.2017.01.18 Abstract ( )   PDF (848KB) ( )   The direct relationship of supply and demand between manufacturer and retailer was brought into the research on the site selection and layout of logistics distribution center, and constructed the nonlinear mixed 0～1 programming model of the site selection and layout of logistics distribution center was conducted through improving the linear programming model of existing general transportation problem with introducing the 0～1 variable of the selection of logistics distribution center. At last, the optimal solution of freightage and the optimal number were obtained, by which the logistics distribution center will be constructed by solving this model with LINGO. Thus, to solutionssuch issues as the site selection and layout of logistics distribution center were put forward. References | Related Articles | Metrics

Vehicle &Electromechanical Engineering

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Numerical Research of Piezoelectric Energy Harvesting from VIV Based on XFlow ZHANG Min1，2，XIE Yulin2，LEI Lin2，LAI Yuyang3 2017, 36(1): 103-109.  DOI: 10.3969/j.issn.1674-0696.2017.01.19 Abstract ( )   PDF (5970KB) ( )   The VIV numerical simulations of a circular cylinder with low mass damping ratio is done by using XFlow based on lattice Boltzmann meshless method. The numerical results are in good agreement with the experimental results. The fluid-mechanical-electric coupled model is established in XFlow and OpenModelica to solve the VIV and Gauss simultaneous equations. The output voltage and power of different values of load resistance are obtained through the numerical analysis. The change rule of the phase difference between the amplitude and voltage is obtained through comparing the amplitude and voltage time traces. The results show that the output voltage increased with the resistance load, the maximum output power can be obtained at a certain stream velocity and load resistance. References | Related Articles | Metrics

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Reserch on Flow Field and Influencing Factors of Tire Hydroplaning Based on CFD Method ZHOU Haichao1，CHEN Lei1，ZHAI Huihui2，LEI Lili1 2017, 36(1): 110-116.  DOI: 10.3969/j.issn.1674-0696.2017.01.20 Abstract ( )   PDF (2293KB) ( )   Tire hydroplaning performance has a decisive influence on vehicle safety and maneuverability, and the pattern structure design parameters directly affect the tire contact area of water movement, which will have a direct impact on tire hydroplaning performance. But due to tire hydroplaning performance test conditions are extremely harsh, and it is difficult to capture the water flow characteristics when hydroplaning occurs. In order to clear the effect of the flow characteristics and pattern structure design parameters on hydroplaning performance when hydroplaning occurs, the hydroplaning analysis model with tire footprint and pattern deformation was established by virtual of the computational fluid dynamics method, and get the flow field distribution features of water film lift, free liquid surface and the groove flow speed. The effects of water film thickness, flow velocity, longitudinal pattern and the cross pattern structure design on hydroplaning performance were analyzed. The results show the water can enter freely the grooves and drainage in the thinner; the circumferential patterns have important influence on tire hydroplaning and adding the number of transverse pattern in footprint can decrease hydrodynamic pressure. References | Related Articles | Metrics