Archive

20 March 2017, Volume 36 Issue 3 Previous Issue    Next Issue
---
Bridge & Tunnel Engineering
Highway & Railway Engineering
Port & Waterway · Hydraulic & Hydroelectric · Resources & Environment
Traffic & Transportation Engineering
Vehicle &Electromechanical Engineering


For Selected:

Download Citations EndNote Ris BibTeX

Toggle Thumbnails

Bridge & Tunnel Engineering

Select

Dynamic Analysis Method of Continuous Beams with Variable Cross-Section Based on Transfer Matrix Method WANG Yuan, ZHANG Songhan, WANG Lu 2017, 36(3): 1-7.  DOI: 10.3969/j.issn.1674-0696.2017.03.01 Abstract ( )   PDF (1299KB) ( )   In order to solve dynamic responses of continuous beams with variable cross-section more efficiently, taking a common kind of continuous beams with variable cross-section as the breakthrough point, the segmental transfer matrix deduction method of continuous beams with variable cross-section and vibration characteristics analysis method were established based on transfer matrix method; meanwhile, the calculation method of dynamic time history under the action of mobile spring quality was also researched. Firstly, starting from the variable cross-section beam bending vibration differential equation, the segmental element transfer matrix deduction method was established; and then the transfer matrix construction method of continuous beams with variable cross-section was derived and its self vibration characteristics analysis was also completed. Secondly, the calculation of dynamic time history of continuous beams with variable cross-section under the excitation of mobile spring quality was completed, combining with Newmark-β method. Finally, the numerical simulation program of dynamic analysis available for continuous beams with variable cross-section was developed in MATLAB. The calculation results show that the proposed method is not only correct and reliable, but also more simple and efficient than the finite element method, which has a certain application prospect. References | Related Articles | Metrics

Select

Stress Measurement of Steel Strands Based on LC Oscillation ZHANG Benniu, YUAN Can, CHEN Zhuomin, LI Xingxing 2017, 36(3): 8-12.  DOI: 10.3969/j.issn.1674-0696.2017.03.02 Abstract ( )   PDF (3287KB) ( )   A steel strand stress detection method based on LC oscillation and magneto-elastic theory was proposed，which only needed to detect the stress at two ends of the steel strand.The basic detection principle was introduced and LC oscillation method was designed.The corresponding experimental system was set up，and the prestressed steel strand was used for stress measurement experiment.Experiment results show that the vibration frequency of the LC oscillator increases with the increase of steel strand stress.Since the proposed method detects stress only at the unloaded place of steel strands，it is hopeful to be used in detecting the pre-stress structures in service. References | Related Articles | Metrics

Select

Vehicle Load Composition and Plane Layout of Asphalt Pavement System of Concrete Curved and Ramp Bridge LI Zhidong, SHI Guijun 2017, 36(3): 13-21.  DOI: 10.3969/j.issn.1674-0696.2017.03.03 Abstract ( )   PDF (2451KB) ( )   Through the investigation of 6 regions，52 sections and 4 large cargo stations in China，the spectrum of various types of traffic and different vehicle axle loads were obtained，and the vehicle load characteristics in the current concrete bridge deck pavement system design were analyzed.Firstly，the current “car-axis-wheel-tire group” and axle load distribution of mainstream heavy truck in domestic were obtained； secondly，combined with the train curve driving footprint analysis，the car and train load model was proposed，which was easy to determinate the most unfavorable load position for numerical analysis of curved and ramp bridge； finally，the plane layout of the load model was set. References | Related Articles | Metrics

Select

Stress and Deformation of Weak-Broken Surrounding Rock of Tongluoshan Tunnel HAN Fenglei, ZHANG Xuefu, YU Wenbing, YI Xin 2017, 36(3): 22-29.  DOI: 10.3969/j.issn.1674-0696.2017.03.04 Abstract ( )   PDF (6555KB) ( )   Double-side-drift method and three-step method is often used during shallow buried and large span tunnel construction，and they have different influences on the stress and deformation of tunnel structure as well as construction schedule.Therefore，according to the comparison and selection of the construction method of Tongluoshan Tunnel in Chongqing，the elastoplastic D-P failure criterions and numerical simulation method were used to study the stress characteristics and the displacement of tunnel surrounding rock and supporting structure with 2 kinds of construction methods，that is the double-side-drift method and three-step method.And the construction schedule was also analyzed by combining with the field construction flow.The study shows that： the three-bench method adopted in Tongluoshan Tunnel can meet safety requirements in the aspects of controlling surrounding rocks displacement，the range of plastic zone and the stress of supporting structure； moreover，it is more advantageous in construction schedule，cost and process arrangement.The research results available in Tongluoshan Tunnel can provide a theoretical basis and practical experience for the similar engineering construction. References | Related Articles | Metrics

Highway & Railway Engineering

Select

Dynamic Response of Viscoelastic Asphalt Pavement under Non-uniform Moving Load HUANG Zhiyi， CHEN Yawen, YAN Kezhen 2017, 36(3): 30-35.  DOI: 10.3969/j.issn.1674-0696.2017.03.05 Abstract ( )   PDF (1604KB) ( )   Based on moving characteristics of the measured non-uniform vehicle load，the dynamic shear modulus of Witczak viscoelastic model was used to establish a three-dimensional finite layer model of asphalt pavement with transient dynamic analysis under non-uniform moving load.The change of time course and the lateral distribution discipline of asphalt pavement dynamic response were analyzed by using 3D-MOVE Analysis software in the cases of different pavement temperature and different vehicle velocity.The above results were compared with the computation results of uniform moving loads.The results show that： the dynamic response of pavement structure has alternating characteristics； base and subgrade strain recovery occur hysteresis phenomenon； the top of surface layer shows stress strain concentration； the transverse distributions of pavement dynamic response exhibit asymmetry in wheel loading area，and the transverse distributions of the maximum dynamic response are different； compared with dynamic response under uniform moving load，the dynamic response under non-uniform moving load has smaller change along the transverse direction； with the increase of the vehicle speed，the dynamic response of surface bottom decreases firstly and then increases，there is a peak point，the critical speed is about 48 km/h； as the pavement temperature increases from -10 ℃ to 50 ℃，the longitudinal strain and transverse strain of surface bottom increases by 2.75 times and 1.53 times respectively； the shear stress of surface bottom increases significantly，and the shear stress of surface bottom is prone to stress concentration below high temperature. References | Related Articles | Metrics

Select

Macro and Micro Analysis on the Compaction Characteristics of Warm Asphalt Mixture Macro and Micro Analysis on the Compaction Characteristics of Warm Asphalt Mixture 2017, 36(3): 36-41.  DOI: 10.3969/j.issn.1674-0696.2017.03.06 Abstract ( )   PDF (3369KB) ( )   Aiming at the hot asphalt mixture and warm asphalt mixture with different molding methods and different compaction times，the experiment research was carried out； at the same time，digital image processing technology was used to obtain the distribution image of their internal voids and aggregates，which were quantitatively described by void fractal dimension and particle area ratio.Therefore，the compaction characteristics of mixture were analyzed from the macro and micro aspects.It is concluded that using void ratio and void fraction dimension can get a basically same conclusion.The distribution structures of internal voids and aggregates of warm asphalt mixture by SGC are almost close at different levels.The close degree of internal vertical aggregate arrangement of warm asphalt mixture is larger by Marshall compaction. References | Related Articles | Metrics

Select

Pavement Performance of Recycled Plastics Modified Asphalt Mixtures YU Jiang, LI Linping, ZHANG Fan, HU Bangyan 2017, 36(3): 42-47.  DOI: 10.3969/j.issn.1674-0696.2017.03.07 Abstract ( )   PDF (1047KB) ( )   The penetration，ductility，softening point，and viscosity performance index of cracking recycled plastics (CRP) / SBS modified asphalts were comprised，and the Marshall test index，high and low temperature stability，water stability and fatigue life of CRP/SBS modified asphalt mixtures were also comprised and studied.Two kinds of CRP adding process——dry mixing and wet mixing——were analyzed. The properties of CRP modified asphalt mixtures using these two adding processes were investigated，and compared with that of SBS modified asphalt mixture in which SBS was wet mixed. The results show that the properties of 5% CRP modified asphalt are similar to that of 4% SBS modified asphalt. The softening points of both CRP/SBS modified asphalts are promoted，and the dynamic stability of both CRP/SBS modified asphalt mixtures surpasses 4 000 r/mm. The AC gradation asphalt mixture can be made by using CRP modified asphalt and SBS modified asphalt which has similar properties.When the CRP content is 5%，the properties of dry mixing CRP modified asphalt mixture are close to those of SBS modified asphalt mixture in which SBS content is 4% and wet mixing，including dynamic stability， freeze-thaw splitting strength ratio and the fatigue life. However，the construction process of dry mixing modified asphalt mixture is simpler. References | Related Articles | Metrics

Select

Comparison on Performance of CRP/SBS Modified Asphalts and CRP/SBS Modified Asphalt Mixtures YANG Xiwu, FANG Yuliang, LIU Ke 2017, 36(3): 48-53.  DOI: 10.3969/j.issn.1674-0696.2017.03.08 Abstract ( )   PDF (2070KB) ( )   In order to realize the on-line monitoring of roadbed compaction to improve the compaction efficiency，the dynamics relationship between vibration roller and the roadbed soil was researched and the dynamics model for roadbed vibration compaction system was established.The technology and method which used vertical vibration acceleration RMS of roller to express the compaction degree of roadbed was analyzed.The research indicates that： the vertical vibration acceleration of roller is positively correlated with the subgrade’s stiffness and negatively correlated with the damping.Through the field test，the regression formula and the correlation coefficient between the compaction degree of subgrade soil and the vertical acceleration RMS of roller were obtained，and the design scheme of the on-line monitoring system for subgrade compactness was also put forward. References | Related Articles | Metrics

Select

Relationship between Roadbed Compaction Degree and Drum Acceleration MA Liying, LIANG Naixing, CAO Yuanwen, GUI Shaoxiong, FAN Wensheng, FAN Youwei 2017, 36(3): 54-59.  DOI: 10.3969/j.issn.1674-0696.2017.03.09 Abstract ( )   PDF (1251KB) ( )   Zhengzhou-Xi’an high-speed railway is the world’s first high-speed railway which crosses the collapsible loess area in a large scale. Based on the construction of Zhengzhou-Xi’an high-speed railway, the subgrade entity experiment was taken as a major study method. A systematic research on the technical problems of subgrade settlement control of high-speed railway in the collapsible loess region was carried out, and comprehensive measures for subgrade settlement control of high speed railway subgrade in collapsible loess area were summarized and proposed. The major engineering measures include six aspects: ①objective evaluation of the collapsibility of loess site; ②loess fill improvement; ③enhancement of the subgrade stiffness; ④adoption of reasonable foundation treatment measures; ⑤artificial acceleration of the subgrade settlement deformation; ⑥conduction of observation and dynamic assessment of subgrade settlement. References | Related Articles | Metrics

Port & Waterway · Hydraulic & Hydroelectric · Resources & Environment

Select

Integrated Technology of High-speed Railway Subgrade Settlement Control in Collapsible Loess Area QU Yaohui, LI Fen, ZHUANG Dehua, MI Weijun, WU Xiaopeng 2017, 36(3): 60-64.  DOI: 10.3969/j.issn.1674-0696.2017.03.10 Abstract ( )   PDF (1657KB) ( )   According to the characteristics of waters，the ship turning around by using the wharf in narrow waters situation was investigated with the assistance of tugs from the perspective of the actual manipulation of ships，and the optimization plan of waters layout was obtained. This proposed plan optimized the navigation environment，solved the problem of supporting swirling waters in ship departing，saved time and reduced the operation costs. Meanwhile，the actual manipulation scale was comprised with the computation scale in current norms，the suggestion that there was still some room for optimizing the wharf apron waters layout scale on the basis of current norms was proposed. References | Related Articles | Metrics

Select

Optimization of Waters Layout of a Port in South China from Navigation Security Perspective HUANG Xiaxing 2017, 36(3): 65-70.  DOI: 10.3969/j.issn.1674-0696.2017.03.11 Abstract ( )   PDF (3279KB) ( )   In order to explore the influence of cap thickness on the stress and deformation of the structure，numerical simulation method was used to study the variation rule of double-row anti-slide pile deformation，stress distribution and load sharing under below situations： with or without pile cap，and the cap thickness changing in 0.25 to 1.25 times of the pile diameter.It is found that the existence of the pile cap plays a key role in coordination with the former and the rear piles deformation and the distribution of internal force，which makes the forcing structure of double row pile more reasonable.Moreover，with the increase of pile cap size and stiffness，the pile internal force and deformation are decreased at a certain degree； but when the ratio of the cap thickness and the pile diameter is greater than 0.5，the reduction effect gradually decreases.Combining research results and structural requirements，it is recommended that the thickness of cap should be 1/2~3/4 of pile diameter and not less than 500 mm，and it should be ultimately determined by the force according to the cap.At the same time，it is found that the inner side of the connection between the pile and the pile cap is easy to have structural damage caused by stress concentration； therefore，the connection should be reinforced. References | Related Articles | Metrics

Select

Stability and Deformation Characteristics of A Certain Reservoir Slope Based on Space-Time Evolution Laws YUAN Xianfan, HU Shuai, YANG Wei, LUO Yu 2017, 36(3): 71-78.  DOI: 10.3969/j.issn.1674-0696.2017.03.12 Abstract ( )   PDF (7810KB) ( )   The stability of right bank side slope in front of the dam of a hydropower station in southwest China was studied based on space-time evolution laws of slope deformation and failure.Besides，the relationship between slope deformation and the rise and fall of water level was studied by integrating slope deformation monitoring data.The results show that： ①Fissures surrounding the landslide have not been formed yet and fracture systems have not been closed，judging from the space evolution laws of side slope deformation and failure； the side slope is in a basically stable state currently，without the danger of landslides, ②With the basic stability of reservoir water level，deformation of the side slope is gradually inclined to a steady increase without the sign of accelerating deformation，and there is no risk of landslides on the side slope currently，judging from the time evolution laws of side slope deformation and failure, ③Seepage fields pointing outside and inner the slope will be formed respectively in the slope in the process of water level rise and fall，which will greatly affect the stability of the slope, ④As the deformation of the side slope is obviously influenced by reservoir impoundment and drainage，it is advisable to reinforce inspection of ground surface fissures and analysis of monitoring data in the process of impoundment and drainage. References | Related Articles | Metrics

Select

Strength Reduction Method Based on Suction Stress DENG Yousheng, LIU Huafei, YAO Zhigang, XU Wentao, WU Peng 2017, 36(3): 79-83.  DOI: 10.3969/j.issn.1674-0696.2017.03.13 Abstract ( )   PDF (1212KB) ( )   The deficiency of strength reduction method for unsaturated soil based on Fredlund formula was analyzed； and then the suction stress theory considering physicochemical force and matric suction was introduced.A strength reduction method for unsaturated soil based on suction stress theory was proposed； and the effect of the unsaturated soil strength reduction method based on the Fredlund formula and the suction stress theory was compared and analyzed respectively by using the finite difference software FLAC3D，the reasonableness and accuracy of strength reduction method based on soil suction stress were verified.The results show that the reduction factor based on the suction stress theory is basically the same with one based on Fredlund formula in the range of common matrix suction and slope angle； moreover，the unsaturated soil shear strength reduction method based on the suction stress theory is more in line with the definition of strength reduction，which has a more clear physical meaning. References | Related Articles | Metrics

Traffic & Transportation Engineering

Select

Calculation of Travel Time Reliability Based on Lognormal Distribution KONG Xiangfu, YANG Jiawen 2017, 36(3): 84-89.  DOI: 10.3969/j.issn.1674-0696.2017.03.14 Abstract ( )   PDF (1254KB) ( )   Traffic congestion not only increases the average travel time, but also increases the travel time uncertainty. It is important to study the uncertainty of travel time to calculate the congestion cost and help the traveler to make a travel plan. Based on the assumption that the travel time length distribution follows the lognormal distribution, 90% travel time length can be expressed as a function of average travel time length and coefficient of variation (COV). By exploring taxi GPS data in Shenzhen, it is found that the fluctuation of COV is less than 10%, which has little effect on 90% travel time length; and 90% travel time length shows a significant linear relationship with the average travel time. The results indicate that the travel time uncertainty linearly rises with the traffic congestion degree. The conclusion provides a theoretical and empirical support for computing the travel time uncertainty. References | Related Articles | Metrics

Select

Review of Delay Parameter Acquisition at the Signalized Intersection ZHANG Huiling, YANG Linyu, AO Guchang 2017, 36(3): 90-97.  DOI: 10.3969/j.issn.1674-0696.2017.03.15 Abstract ( )   PDF (1009KB) ( )   The definition of several delays and the relationship among different delays at signalized intersection were reviewed firstly.Secondly，the commonly used field investigation，simulation，theoretical analysis and other methods to obtain the signalized intersection delay were summarized.According to the theoretical analysis method，the Webster delay model was deduced in detail，and the classic models of the theoretical analysis method widely used in a long history were described，including HCM2000，Miller and Akcelik.Moreover，the characteristics of the above classic models in the parameter acquisition were analyzed.By use of the principle of point sample method，the application of video method in delay acquisition was introduced.Finally，the field investigation，simulation method and theoretical analysis method to obtain the delay method were reviewed and discussed.Combined with the current research，the development trend of the acquisition of delay parameters was also analyzed， References | Related Articles | Metrics

Select

Optimal Design of Nonprestressed Crashworthy Movable Guardrail LEI Zhengbao, LI Jinxin 2017, 36(3): 98-102.  DOI: 10.3969/j.issn.1674-0696.2017.03.16 Abstract ( )   PDF (3473KB) ( )   In order to develop the crashworthy movable guardrail with convenient installation on site at a maximum degree，whose crashworthy rating reached A grade (160KJ)，a new nonprestressed semi-rigid crashworthy movable guardrail was designed according to the Standard for Safety Performance Evaluation of Highway Barriers (JTG B05-01-2013).The guardrail was constituted by three rows of steel pipes，and angle steel and square tubes were spliced into “wang” as the connector structure in the middle.The thickness of the steel pipe and terminal structure of movable guardrail were optimized through the simulation calculation，and then the most optimal parameters of steel pipe thickness and terminal structure were determined.The crashworthy movable guardrail with the above optimal designs meets the standard of guardrail safety evaluation indexes of vehicle trace，acceleration and etc.. References | Related Articles | Metrics

Select

Impact of Extreme Water Levels on Characteristics of Vessel Traffic Flow in the Middle Reaches of Yangtze River LU Shengrong, LIU Yao 2017, 36(3): 103-107.  DOI: 10.3969/j.issn.1674-0696.2017.03.17 Abstract ( )   PDF (928KB) ( )   Navigation condition in the middle reaches of Yangtze River is easy to be changed under extreme water levels，and traffic control measures may need to be taken by the navigation administrative departments.These measures have great impact on the macro and micro characteristics of vessel traffic flow.Taking Taipingkou waterway under extreme low water level for example，the traffic control measure is upstream and downstream closure of navigation intermittently.Combining with vessel traffic wave model under linear relationship between speed and density，the gathering and dissipation process of vessel traffic flow before and after closure was elaborated.The study indicates that the maximum queue length and blocking time caused by closure of navigation is positively proportional to the time of closure of navigation.It is necessary for the navigation administrative departments to formulate scientific and detailed plan to minimize the effect of closure of navigation. References | Related Articles | Metrics

Select

Network Construction of Arctic Route and Traditional Route under Seasonal Influence LIN Guolong, TANG Bingbing, DING Yi 2017, 36(3): 108-114.  DOI: 10.3969/j.issn.1674-0696.2017.03.18 Abstract ( )   PDF (1410KB) ( )   Based on the airworthiness characteristics of the arctic routes and the traditional routes as well as OD container transportation demand among the ports along the routes，a 0-1 integer programming model was formulated，whose target was to minimize the total transportation costs of all containers，to build a new container shipping network of the northern hemisphere，and thus to acknowledge the change of the shipping network and the distribution of its OD containers after the opening of the arctic route.Combined with the airworthiness characteristics of each channel，traffic impedance functions were set for various routes according to different ship types，and CPLEX was used to solve the model.A case study of COSCON FAL1 routes was carried out and analyzed.The results show that the flow of the arctic route accounts for 2.35% of the total flow of the whole network in winter and spring and 30.25% in summer and autumn； and the proportion will rise to 48.93% if the arctic route is available all the year. References | Related Articles | Metrics

Vehicle &Electromechanical Engineering

Select

Vehicle & Electromechanical Engineering HE Ren, XIE Da 2017, 36(3): 115-120.  DOI: 10.3969/j.issn.1674-0696.2017.03.19 Abstract ( )   PDF (2467KB) ( )   On the basis of hydraulic speed-bump energy recovery system，AMESim simulation technology was applied to research the characteristics of a kind of double hydraulic cylinder transducer.Through the modeling analysis of double hydraulic cylinder transducer，the relationship among the velocity as well as the stroke of transducer，the gas volume as well as the inflation pressure of accumulator and the hydraulic cylinder diameter as well as the spring stiffness of transducer was established initially，which provided a reference for the development for the prototype of hydraulic speed-bump energy recovery system. References | Related Articles | Metrics

Select

Optimization Design of Cyclone Separator of Heavy Truck Intake System Based on Numerical Simulation WANG Renren, GAO Chao 2017, 36(3): 121-126.  DOI: 10.3969/j.issn.1674-0696.2017.03.20 Abstract ( )   PDF (1952KB) ( )   The internal air flow model of the cyclone separator for heavy truck intake system was established，and the numerical simulation of internal flow for exhaust ports with different sizes was carried out.Therefore，the size of exhaust port with minimum flow resistance was obtained.The calculation results show that the lowest points of the average speed，the average pressure and the pressure drop are corresponding to different exhaust port sizes.Comprehensively considering the influence of the above 3 parameters on the cyclone separator，the average value of the corresponding 3 dimensions is taken as the optimization result. References | Related Articles | Metrics