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21 August 2018, Volume 37 Issue 08 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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Fatigue Damage Assessment and Experimental Study on Steel Box Girder of Taizhou Yangtze River Bridge JI Lin1，KONG Xiangming2，JIANG Bo1，YUANZHOU Zhiyuan2 2018, 37(08): 1-5.  DOI: 10.3969/j.issn.1674-0696.2018.08.01 Abstract ( )   PDF (727KB) ( )   The 3D simulation model was established for the analysis of dynamic response of Taizhou Yangtze River Bridge to determine the most unfavorable fatigue damage section. The fatigue stress test was conducted on the deck and U-rib joint weld of the most unfavorable section, and the fatigue damage characteristics were analyzed. In addition, the fatigue test was carried out and the fatigue strength of the detail was evaluated by the nominal stress method. The results show that the most unfavorable section of Taizhou Yangtze Bridge lies in the mid-span of the steel box girder. Under the current traffic volume, the maximum stress amplitude of the measuring points of deck and U-rib weld in the mid-span section is much lower than the fatigue threshold recommended by the BS5400 standard. The fatigue strength of deck and U-rib weld of Taizhou Yangtze River Bridge conforms to the specifications. References | Related Articles | Metrics

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Application of Stress-Free State Method in Long-Span Arch Bridge Construction ZHOU Yin, ZHANG Xuesong, DING Yanchao 2018, 37(08): 6-10.  DOI: 10.3969/j.issn.1674-0696.2018.08.02 Abstract ( )   PDF (479KB) ( )   In order to realize the reasonable bridge state that the stress state of the arch rib of the long-span arch bridge will be the same as the design after the construction of the bridge, the specific implementation of the stress-free state method was discussed, taking the long-span arch bridge with cable hoisting, the cantilever casting, the rotation construction and etc. as the research object. The cable force calculation formula was derived, and the control conditions for the displacement and curvature constraint of the arch rib during the adjustment process were proposed. The stress-free state method was applied to the construction calculation of the 500 m concrete filled steel tube arch bridge and the 200 m cantilever casting arch bridge. The calculation results show that the alignment and internal force of the arch rib after arch are consistent with the design condition. References | Related Articles | Metrics

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Fitted Evolutionary Power Spectra of Explosive Ground Motion Based on Kameda ModelDamage Mechanism of Outer Sheath of Slings in Service and Life Prediction Method CHEN Huiguo1,SONG Hao2,ZHONG Ting1，LIU Guocui1,WANG Miaoshuo1 2018, 37(08): 11-15.  DOI: 10.3969/j.issn.1674-0696.2018.08.03 Abstract ( )   PDF (551KB) ( )   Based on the non-stationary vibration method, the Kameda evolutionary power spectrum model was used to simulate the explosive ground motion. The rationality of the Kameda evolutionary power spectrum was analyzed by combining the actual explosive ground motion. The feasibility of the Kameda model was verified by comparing the acceleration, the response spectrum, the intensity envelope and the cumulative times of zero-crossing of the fitting time history and the recorded time history. The research shows that the time-frequency non-stationary explosive ground motion can be fitted by the Kameda evolutionary power spectrum model. References | Related Articles | Metrics

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Monitoring and Analysis of Support Structure Stress of Railway Tunnel under Soft Surrounding Rock Condition HUANG He1, ZHOU Dingheng2, LI Fengling1 2018, 37(08): 16-22.  DOI: 10.3969 /j.issn.1674?0696.2018.08.04 Abstract ( )   PDF (611KB) ( )   Based on the engineering background of ZhujiashanTunnel on Baoji-Lanzhou Passenger Dedicated Lines, the rule of the parameters changing with the time and the spatial distribution characteristics were studied by in-situ monitoring, such as surrounding rock pressure, steel frame stress, the initial support concrete stress, the initial support and inner lining contact pressure and second lining concrete stress.The research results show that the surrounding rock pressure of Vb class rock is larger than that of IVb class rock,but the pressure distribution uniformity of Vb class rock is better than that of IVb class rock; the surrounding rock pressure of left side is larger than that of the right side for IVb class rock. The whole steel frame is in the state of compression and the uneven distribution of Vb section is more obvious than that of IVb; the stress of vault and left arch foot of Vb class rock exceeds 200 MPa.The initial support concrete stress distribution of the two types of surrounding rock is uneven, and some parts are tensile stress during construction; the initial support concrete stress of the inverted arch is much larger than that in other locations, exceeding the allowable value. After inner-lining construction,the initial support and inner lining contact pressure increase in a short time and then reduce to a stable value.That means the problem of bearing capacity reduction in fault fracture zone has been improved. The distribution of second lining concrete stress is not uniform; the stress of vault, right arch waist and wall middle are larger;especially the stress of the vault is the largest and exceeds the allowable value. Based on all monitoring results, the stress of steel frame and concrete in some places is too large and even exceeds the allowable values. Therefore, appropriate construction control measures need to be taken. References | Related Articles | Metrics

Highway & Railway Engineering

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Experimental Study on Physical Properties of Heavy Bio-oil Recycled Asphalt ZHU Hongzhou, ZHONG Weiming, WAN Yiqiu, XIANG Hao, YANG Yang 2018, 37(08): 23-28.  DOI: 10.3969/j.issn.1674-0696.2018.08.05 Abstract ( )   PDF (512KB) ( )   In order to study the feasibility of regeneration of aging asphalt by using biological heavy oil, three kinds of heavy bio-oil was selected to carry out the experiment. Physical and chemical properties of three kinds of heavy bio-oil such as specific gravity, viscosity, and moisture content were tested; the elemental analysis and infrared spectrum analysis were undertaken. 70# asphalt under indoor aging simulation experiment was blended with three kinds of heavy bio-oil in the proportion of 2%, 4%, 6% and 8% respectively. The penetration, ductility, softening point and viscosity tests were undertaken to analyze differences of the regeneration effect of three kinds of bio heavy oil on 70# aging asphalt. Besides, the optimal dosage of heavy bio-oil was determined according to the method for the optimum asphalt usage of asphalt mixtures. The results show that: (1) with the increase of bio-oil dosage, there is a downward trend for softening point and viscosity of aging asphalt, while there is a upward trend for penetration and docility of aging asphalt; (2) there are differences among different types of heavy bio-oil in regeneration performance; the regeneration effects of heavy bio-oil A and B are better while the regeneration performance of heavy bio-oil C is slightly worse; (3)the optimum contents of heavy bio-oil A, B and C are 3.9%, 4.6% and 6.4% respectively. References | Related Articles | Metrics

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Self-healing Properties of Bio-oil Regenerated Asphalt BAI Aiming1, ZHOU Xinxing2 2018, 37(08): 29-33.  DOI: 10.3969/j.issn.1674-0696.2018.08.06 Abstract ( )   PDF (814KB) ( )   In order to improve the self-healing property of asphalt and improve the reaction energy barrier of asphalt in the process of self-healing,the bio-oil regenerated asphalt extracted by waste wood was used to evaluate the self-healing property of the bio-oil regenerated asphalt from energy and chemical structure perspective, through the dynamic shear rheometer (DSR) and molecular simulation technology.The reaction energy barrier and healing index of bio-oil regenerated asphalt are 32.52KJ/mol and 0.596 respectively during the self-healing process of modified asphalt when the addition of bio-oil is 8.0wt%. The results show that the bio-oil can decrease the reaction energy barrier and improve the fatigue lifetime, healing index, and self-healing property of the asphalt.The variation of steric configuration of asphaltenes and resins is not big, while that of the steric configuration of saturates and aromatics is great; the morphology of saturates and aromatics gets together during the self-healing process.The influence of bio-oil on the steric configuration of asphalt molecules is significant. References | Related Articles | Metrics

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Characteristics and Technology Standard of Buton-Asphalt-Rock LU Xueyuan1, LING Dongqiang2, HU Yingde3 2018, 37(08): 34-44.  DOI: 10.3969/j.issn.1674-0696.2018.08.07 Abstract ( )   PDF (1281KB) ( )   In order to reveal material characteristics and technology standard of the Buton-asphalt-rock(BAR), different test methods and micro-analysis methods were used respectively to study the gradation, Buton asphalt(BA), rock material and coating of the long-term applied BAR and modified asphalt.The results show that the test method of centrifugal separation can accurately control the BA content of BAR; the test methods of dry screening, and washing screening after centrifugal separation are respectively applied to control the particle gradation range of BAR and BR; Abson test method can effectively control the quality of the recovered BA. The structure characteristics of BR are revealed from the microscopic mechanism, and the result that the rock mineral material is composed of calcareous silicate minerals and has strong adhesion with BA is obtained by analysis and demonstration. The coating mechanism and adhesion of 4 kinds of bituminous binder materials were evaluated and analyzed. The result shows that the longer of the mixing time of BAR and coarse aggregate,the larger of the coating surface and the better of the adhesion, which is consistent with micro-analysis results. Therefore, the technology indicators and control standard for BAR and its composite modified asphalt were proposed. References | Related Articles | Metrics

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Correlation between Fractal Dimension Characteristics and Road Performance of Asphalt Mixture Gradation HUANG Weirong1，XIONG Yixiao2，XI Lei2 2018, 37(08): 45-50.  DOI: 10.3969/j.issn.1674-0696.2018.08.08 Abstract ( )   PDF (561KB) ( )   Through the analysis of the fractal dimension characteristics of gradation of GAC-13C asphalt mixture, the correlation between pavement fractal dimension and road performance was studied. The relationship between fractal dimension and gradation with and without segmented regression was analyzed. The correlation between the pass rate of 4.75 mm and the fractal dimension was compared. According to the related results of Marshall test parameters, high temperature stability and skid resistance test, the correlation between the gradation fractal dimension characteristics of changing the pass rate of 4.75 mm sieve hole and the road performance of the mixtures was discussed. The results show that: the correlation between the pass rate of 4.75 mm and the segmented fractal dimension is better; with the decrease of pass rate of 4.75 mm, the fractal dimension of GAC-13C type asphalt mixture gradually increases and the gradation becomes coarser. At the same time, the fractal dimension and Marshall test parameters, high temperature stability as well as skid resistance of mixtures have good correlation. References | Related Articles | Metrics

Port & Waterway · Hydraulic & Hydroelectric · Resources & Environment

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Properties and Mechanism to Clean up the Entanglements in Waterway Using Water Jet LIU Zhaocun1,2,3, YU Kui1, SUN Peng1, ZHOU Shiliang1, ZHAO Teng1, WANG Xiaoqing1,2 2018, 37(08): 51-56.  DOI: 10.3969/j.issn.1674-0696.2018.08.09 Abstract ( )   PDF (755KB) ( )   On the basis of the developed prototype, the properties to clean up the entanglements in waterway by using water jet were experimentally studied. The interaction and movement characteristics between the abrasive material and the flow were investigated. The cause to form the sawtooth shape of cutting section was explained; and the experimental formula for cutting characteristics was obtained. On the basis of many sets of test results in experimental case and natural field condition, the cutting mechanism of the water jet of the abrasive material was analyzed. It is discovered that the erosive effect of the abrasive material and the splitting effect of the high speed flow are dominating factors; especially, the former factor has more remarkable effect to clean up the entanglements. References | Related Articles | Metrics

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Seepage Stability Calculation Method for Rock Slope with Two Sets of Joints SUN Ming 2018, 37(08): 57-62.  DOI: 10.3969/j.issn.1674-0696.2018.08.10 Abstract ( )   PDF (807KB) ( )   For the seepage stability problem of rock slope with joints, the physical model and mechanical model for the rock slope with two sets of joints were established, and its stability calculation method was proposed by limit equilibrium theory. Based on the seepage law of single joint under stress condition, the normal stress and shear stress of fissure surface were equivalent to the maximum principle stress and the minimum principle stress; the seepage velocity and seepage driving force of single joint was obtained, and then the seepage stability calculation method for rock slope with two sets of joints was proposed. The stability calculation results of 5 high and steep rock slope with two sets of joints in Shouli Mountain, Wanzhou District show that: under the influence of seepage driving force, slope W123 and W132 vary from basically stable state to unstable state; the seepage stability coefficient reduces by 1.5%~5.7%, compared with non-seepage stability coefficient. For rock slopes with filling fissure, no cut-through fissure and fissure with lesser opening, the seepage driving force may not be considered; but for the rock slopes with better connectivity and fissure with larger opening, the seepage driving force should not be neglected. References | Related Articles | Metrics

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Stereographic-Real Proportion Projection Method and Its Application TANG Shengchuan1, FENG Deng2,3, WANG Junjie2,3 2018, 37(08): 63-68.  DOI: 10.3969/j.issn.1674-0696.2018.08.11 Abstract ( )   PDF (881KB) ( )   The stereographic-real proportion projection method has a unique advantage in the stability analysis of the rock slope. In the case study of a certain rock slope in Heishangu, the comprehensive analysis of the slope was carried out by adopting the stereographic-real proportion projection method. The important features such as sliding mechanism, sliding direction, sliding surface area and sliding body volume were analyzed. And the rock slopes stability was also analyzed by the stereographic-real proportion projection method. The advantages and disadvantages of the stereographic-real proportion projection method and the transfer coefficient method in the traditional limit equilibrium method were discussed. The results show that the stereographic-real proportion projection method has more advantages than the transfer coefficient method in the analysis of rock slopes stability, which can provide reference for the protection of rock slope. References | Related Articles | Metrics

Traffic & Transportation Engineering

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Optimization of Yellow Signal Duration Considering the TypeⅠ Dilemma Zone ZHANG Yaping, WEN Liang, QI Shouming, MO Qiong 2018, 37(08): 69-74.  DOI: 10.3969/j.issn.1674-0696.2018.08.12 Abstract ( )   PDF (525KB) ( )   The typeⅠdilemma zone caused by yellow signal is one of the potential unsafe factors of traffic accidents. In order to reasonably set yellow signal duration, eliminate the typeⅠdilemma zone and ensure the safety of vehicles running at the intersection, the traffic parameters of vehicle on straight lane and exclusive left-turn lane at the signal intersection with 60km/h speed limit were collected by video observation method. The functional relationship among parameters were established by SPSS analysis software. TypeⅠdilemma zone model was established based on the classic GHM model. The optimization result of yellow light signal duration with different signal phases was obtained by MATLAB simulation. By contrasting the boundaries of dilemma zone, typeⅠdilemma zone can be effectively eliminated when the yellow signal duration of the straight phase is 5 seconds and that of the exclusive left-turn phase is 4 seconds. References | Related Articles | Metrics

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Dynamic Queuing Theory and Its Optimization for Large Bus Station LIU Wei, CHEN Kequan, XIE Zhongjin 2018, 37(08): 75-80.  DOI: 10.3969/j.issn.1674-0696.2018.08.13 Abstract ( )   PDF (461KB) ( )   Bus station is the critical nod in the bus transit system. The service level of the bus station not only affects the operation efficiency of the bus, but also directly influences the operation condition of the surrounding traffic. In order to improve the efficiency of traditional bus crossing through the bus bay stop, the characteristics of vehicle operation and passenger waiting in public transport platform were analyzed firstly. The basic parameters in the queuing theory model were introduced, and the service time was improved to be a function which dynamically varied according to the number of vehicles in the station. Meanwhile, according to the law of bus arrival at different time periods, the time interval parameters were used to improve the accuracy of the model. Secondly, the main and auxiliary station were set in the bus bay stop, therefore, the platform was modeled as a M/M/2/N system; the guiding mode of intelligent bus stop was made. Finally, the proposed model was applied in a case study of Damiao bus station in Chongqing. The current survey shows that the interior delay time of Damiao bus station accounts for 40.1% of the total running time, and the time of bus passing through Damiao bus station will increase sharply during the rush hour. The entry and exit order of bus in Damiao bus station can be effectively controlled by using the platform zoning management and public traffic intelligent guidance model. The number of queuing vehicles is reduced by 77.5% and there is no queuing overflow, meanwhile, the time of vehicles passing through Damiao bus station is reduced by 41.1% during the rush hour. References | Related Articles | Metrics

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Prediction of Target Passengers Travel Intention of Customized Public Transport Based on Wavelet Neural Network JIN Wenzhou, HAN Bowen, HAO Xiaoni, HUANG Weiqi 2018, 37(08): 81-87.  DOI: 10.3969/j.issn.1674-0696.2018.08.14 Abstract ( )   PDF (463KB) ( )   In the face of the increasingly diverse needs of people travel, more and more customized public transport appears in the peoples life. Before planning a new type of public transport which means to provide the customized travel services for target passengers, it is necessary to predict the target passengers travel intentions. Considering the complexity of the influence factors of travel intention, a predict method based on wavelet neural network was proposed. First of all, according to the survey of passengers travel intention, the factors affecting the target passengers travel intention were analyzed; and then the neural network model was constructed.Finally, the forecast was verified and implemented by using MATLAB. In order to improve the training effect of the network, the self-adaptive method was used to determine the networks learning rate and the number of hidden layer nodes.The results show that the wavelet neural network has good applicability for the prediction of target passengers travel intention of the customized public transport, and has better prediction accuracy than the traditional BP neural network. References | Related Articles | Metrics

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Impact of En-route Traffic Information on Travel Route Choice ZHAO Huaiming1, TAN Yu2, LI Bowei2 2018, 37(08): 88-95.  DOI: 10.3969/j.issn.1674-0696.2018.08.15 Abstract ( )   PDF (604KB) ( )   Traffic information guidance, which is an important aspect of ITS research, is an effective measure to balance the traffic flow in the network and ease the traffic congestion. The effect of traffic information guidance on traffic performance of road network was investigated, such as queue length, delay, and vehicle kilometers; and storage-and-forwarding computation model was proposed. A case study of Amsterdam road network in Holland was conducted to analyze the impact of providing instant traffic information and predicted traffic information on the travel route choice in the condition of traffic incident and no traffic incident; meanwhile, the travelers compliance degree to the traffic information was also considered. Results show that among all cases travelers benefit most by providing them with the predicted information in the case of traffic incident. References | Related Articles | Metrics

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Intercity Traffic Mode Based on a Nested Logit Model JIANG Dengying, YU Ling 2018, 37(08): 96-101.  DOI: 10.3969/j.issn.1674-0696.2018.08.16 Abstract ( )   PDF (408KB) ( )   Aiming at the reasonable planning of intercity traffic mode, the share rate of traffic mode was investigated. Firstly, the utility function was established by disaggregate theory and random utility theory, whose weight was calculated by maximum likelihood estimation, and the influence of travelers with different income on the weight was considered. Then, considering the correlation among different traffic modes, the relative utility was used to take the place of the absolute utility; and the improved nested Logit model was established. Finally, the share rates of various traffic modes were calculated, combining with the share rate models and the questionnaire results of travelers from Wuhan to Xianning. The feasibility and effectiveness of the proposed model was verified by comparing with the calculation results,the nested Logit model and the actual share rate of passenger flow.The proposed model has important guiding significance and reference value for the future division and management of intercity traffic modes. References | Related Articles | Metrics

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Uneven Illumination License Plate Image Recognition Base on Template Matching Method LING Xiang, LAI Kun, WANG Xipeng 2018, 37(08): 102-106.  DOI: 10.3969/j.issn.1674-0696.2018.08.17 Abstract ( )   PDF (619KB) ( )   For fast and accurate recognition of uneven illumination license plate images, a new license plate recognition algorithm based on improved top-hat reconstruction and template matching was proposed. Firstly, the gray scale top-hat reconstruction was applied to do pre-processing, enhance the detail information of the image as well as weaken the interference of the environment and light conditions to the license plate character information. Secondly, the improved projection segmentation method was used to segment the binary license plate image and extract the character image. Finally, tests on the images collected from different places and different natural conditions were carried out. The test results show that the proposed algorithm has excellent performance. On the basis of the above, a template matching function based on global coincidence degree of character image was proposed, and tests were done on images of different kinds of samples. The test results show that the matching function is proved to be accurate and feasible for license plate recognition, and has good performance. References | Related Articles | Metrics

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Model of Route Short-Time Utilization Rate Based on Flight Level ZHANG Zhaoning，CAO Yueqi 2018, 37(08): 107-111.  DOI: 10.3969/j.issn.1674-0696.2018.08.18 Abstract ( )   PDF (389KB) ( )   The route utilization rate is an important index to measure the use of area control airspace. The short-time utilization rate assessment is an important means to adjust and monitor the technology in airspace use. For the utilization rate of a single route rather than the whole space, the calculation model of utilization rate was established from the perspective of flight level. According to the operation of airspace system, which took the capacity, the time and space constraints in consideration. A breakthrough had been made in the short-term utilization rate, quantifying the utilization rate, not just using the evaluation method to get the level value of utilization rate. Firstly, the calculation model of utilization rate of single flight level in time slice was established. And then the route utilization rate was obtained by integrating the utilization rate of each flight level. Secondly, considering the utilization rate was time-varying, the route short-time utilization rate model was obtained by synthesizing the utilization rate of each time slice. Finally, taking an area control center as an example, its route short-time utilization rate value and variation of the utilization rate from 9:00 to 10:00 was obtained. References | Related Articles | Metrics

Vehicle &Electromechanical Engineering

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Controller Design for Vehicle Macpherson Active Suspension Based on LPV Model ZHAO Qiang1, HE Fa2 2018, 37(08): 112-118.  DOI: 10.3969/j.issn.1674-0696.2018.08.19 Abstract ( )   PDF (661KB) ( )   According to the two-dimensional structure of Macpherson active suspension, the dynamical equations of active suspension considering Macpherson type was established by Lagrange formula with dissipative energy. The dynamical equations were further linearized at its equilibrium position and converted into the state equation form. According to the uncertainty of the sprung mass, the LPV model of the Macpherson suspension was established and then a state feedback robust H∞ controllerwas designed with regional poles assignment method and LMI technique. The proposed controller was simulated in Matlab/Simulink. The simulation results show that vehicle with Macpherson active suspension using a state feedback robust H∞ controller on regional poles assignment has great improvement in ride comfort and suspension stability, and its performance obviously outperforms the corresponding passive Macpherson suspension with the same parameters. References | Related Articles | Metrics

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Stability of Monorail Vehicle Considering Tire Nonlinear Characteristics ZHAO Shuen，LUO Baoliang，LI Yuling 2018, 37(08): 119-126.  DOI: 10.3969/j.issn.1674-0696.2018.08.20 Abstract ( )   PDF (609KB) ( )   In order to study the running stability problem of straddle type monorail, the straddle type monorail line in Chongqing was taken as the research object to establish the multibody dynamic model of 15-degrees-of-freedom, in which the PC track girder was regarded as rigid body and the non-linear characteristic of the rubber tire was considered. The dynamic differential equation of vehicle running was derived from Lagrange principle. Based on the simulation of PC track beam pavement in the American six road spectrum, the running stability of the straddle type monorail vehicle with different speed and variable radius of curvature was simulated and analyzed. The results show that in the small radius of curvature during the driving, the running stability of the vehicle decreases with the increase of the vehicle speed and increases with the increase of the radius of curvature. References | Related Articles | Metrics