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30 August 2015, Volume 34 Issue 4 Previous Issue    Next Issue
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Bridge & Tunnel Engineering
Highway & Railway Engineering
Port & Waterway ? Hydraulic & Hydroelectric ? Resources & Environment
Transportation Engineering
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Bridge & Tunnel Engineering

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Influence of Foundation Settlement on Bridge Structure in Coastal Area and Processing Method Xiang Zhongfu, Liu Xiangyu, Xu Lige 2015, 34(4): 1-6.  DOI: 10.3969/j.issn.1674-0696.2015.04.01 Abstract ( )   PDF (1061KB) ( )   Superstructure stress concentration and cracking were often caused by the uneven foundation settlement during the design and construction of bridge across the estuary and in coastal area. ABAQUS was adopted to analyze the lateral displacement of the pile in the role of foundation settlement under six conditions, including the original design condition, the change the pile diameter, the increase of the anchor with various pile diameters, the increase of steel on the basis of cofferdam pile diameter as well as the change of the quantity and form of 0# cloth pile. In view of the pile foundation displacement under different conditions, the idea that the upper structure kept the bridge span unchanged was put forward, but the upper part was adjusted to the simply supported structure, and the hollow slab was used. The pile diameter of the lower part structure was still 1.2 m, and the soil on the pile pushing role was decreased through the setting of large diameter steel casing cofferdam. Treatment options were proposed, such as setting empty abutment, increasing tensile anchor structure, and the auxiliary measures of force dissipation hole. This method has achieved good results in practical application. References | Related Articles | Metrics

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Experimental Study and Analysis on Shear Lag Effect of Prestressed Composite Beam Structure Composite Beam Structure Hu Shaowei, Yu Jiang, , Xie Jianfeng, Xu Aiqing 2015, 34(4): 7-14.  DOI: 10.3969/j.issn.1674-0696.2015.04.02 Abstract ( )   PDF (1135KB) ( )   In order to make an in-depth analysis on shear lag effect of prestressed steel-concrete composite beam structure, a new type of double-box steel-concrete composite beam with wide flange was proposed and researched through the test, and its load-stress curves, load-strain curves, and load-deflection curves were discussed under mid-span concentrated load. Based on the warping displacement model assumption, governing differential equations were established by the minimum potential energy principle, and expressions of strain and deflection were deduced considering both shear lag effect and prestressed increment. Finally, combining with the example, contrastive analyses on shear lag effect between test and theory were also launched within the elastic stage, analysis solution showed that the error within 15%. References | Related Articles | Metrics

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Automatic Monitoring System for Displacement of Pier and Beam of Curved Bridge Tian Shiqing, Cao Hong, Wang Junxin, Zhang Minghui 2015, 34(4): 15-19.  DOI: 10.3969/j.issn.1674-0696.2015.04.03 Abstract ( )   PDF (1268KB) ( )   For curved bridge piers, beams, bearings and expansion joints diseases occur interrelated phenomena, design and development of the bending beam displacement pier automatic monitoring system. Combined effects of thermal expansion and contraction, and system installation affect the original pier excursion between the beam monitoring values deduced through theoretical actual offset value formula pier beams; to achieve the displacement of the expansion joints by image acquisition mode artificial situation interpretation, real-time observation of the bearing state, and to realize the displacement sensor to collect data validation obtained; mobile data transmission over a wireless network to a server, and the server software system called data processing, form data graphs, export monitoring data; to overrun situation timely messages warning, so as to achieve a timely and effective early warning monitoring points are functional damage conditions. References | Related Articles | Metrics

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Digital Pressure Sensor and Its Application for Vertical Displacement Measurement Based on MEMS Measurement Based on MEMS Zhu Shifeng, Zhou Zhixiang, Wu Haijun 2015, 34(4): 20-27.  DOI: 10.3969/j.issn.1674-0696.2015.04.04 Abstract ( )   PDF (4401KB) ( )   A vertical displacement sensor based on MEMS (Micro-Electro-Mechanical System) and connecting pipe technology was developed for convenience, highprecision, realtime remote monitoring of the vertical displacement. Measurement principle of closed differential pressure connecting pipe displacement was elaborated and the test module was realized. The application performance of closed differential pressure connecting pipe displacement sensor was mainly analyzed from the view of stability and reliability. Initial experiment results show that the resolution of this sensor is higher than 0.1 mm in vertical displacement measurement; the sensitivity is relatively high, with longterm stability 0.3 mm. The daily need for displacement monitoring and measurement is met. It has been successfully applied in bridge deflection measurement of the bridge static load test, which shows that the system has many advantages such as realtime monitoring, low implementation cost, easy to be operated and so on. References | Related Articles | Metrics

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Control Method of Concrete Continuous Bridge by Cantilever Casting Construction Sun Yongming, Rong Xueliang, He Xiaodong 2015, 34(4): 28-33.  DOI: 10.3969/j.issn.1674-0696.2015.04.05 Abstract ( )   PDF (586KB) ( )   Construction control theory and method of long-span prestressed concrete continuous beam bridge were summarized and estimated, and both of parameter identification and state preforest were necessary functions in the selfadaptive construction control system of longspan prestressed concrete continuous beam bridge. The deviation feedback equations were set up by theoretical calculation elevations and measured elevations of every cantilever segments, and the feedback deviations were divided into three parts, including measuring deviation, parameter deviation and system deviation. By introducing the vector of the parameter correction coefficient, the parameters of the beam segment weight, the hanging basket stiffness, the prestressing effects and shrinkage and creep of concrete could be corrected at real time. The correction coefficient of beam stiffness was calculated by the elevation deviation of moving hanging baskets, the correction coefficients of beam weight and hangingbasket stiffness were calculated by the elevation deviation of pouring concrete. The correction coefficient of prestressed effects was calculated by the elevation deviation of tensioning prestressed strands,and the system deviations were calculated by the total deviation of constructing one segment. Finally, every parameter correction coefficients and system deviations of next segment were predicted by the modes of GM (1, 1) and CGM (1, 1) based on gray prediction theory; moreover, the formwork erection elevation of the awaiting constructed beam segment was gained. Tested by the engineering example, with the cantilever segments increased, the total number of samples constantly was increased. The methods and formulas of parameter identification were proposed, which could rapidly and accurately identify the true values of every parameters, and predictive values based on gray prediction theory could be relatively stable near the true values. References | Related Articles | Metrics

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Grouting Pre-reinforcement Mechanism and Effect Evaluation in WaterRich Loess Tunnel in Water-Rich Loess Tunnel Xue Xiaohui, Zhang Jun, Su Zhongming, Sun Zhijie 2015, 34(4): 34-38.  DOI: 10.3969/j.issn.1674-0696.2015.04.06 Abstract ( )   PDF (606KB) ( )   In order to solve the problem of water-rich loess tunnel in construction process, based on the idea of underground water environmental balance, the Kuniaki Sato empirical formula and underground runoff modulus was used to build correlation function and get the permeability coefficient. Combining the engineering practice condition of the Qiaoyuan tunnel, the duplex pipe grouting was used to reinforce the water-rich loess tunnel, and its grouting effect was also evaluated in detail. Results show that there are a lot of obvious grouting veins on tunnel face, and the bedding is clear. There is not bleeding phenomenon on tunnel face. The surrounding rock is stable, no such phenomena occur as collapse, instability, gushing water or mud, etc. The soil strength increases dramatically, and the permeability reduces significantly. The permeability coefficient of grouting soil meets the requirements of underground water environmental balance. References | Related Articles | Metrics

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Major Technical Measures of the Third Series Argillaceous Weak Cementation Rich Water Silty Sand Rock Tunnelss Weak Cementation Rich Water Silty Sand Rock Tunnelss Li Guoliang, Wang Fei 2015, 34(4): 39-44.  DOI: 10.3969/j.issn.1674-0696.2015.04.07 Abstract ( )   PDF (1204KB) ( )   In order to solve the serial engineering problems caused by the third series argillaceous weak cementation rich water silty sand in the construction process of Lan-Yu and Ningxia Wangwa railway, the surrounding rock characteristics of the third series argillaceous weak cementation rich water silty sand rock systematically were elaborated, the main auxiliary technical measures and engineering plans were introduced, and the design measures and the key construction technology of this stratum were put forward, in the consideration of the engineering and scientific difficulties in construction of Tao Shuping, Hu Maling, Cheng’er Shan tunnels, et al. The major principle that “major precipitation, concentrated catheters, strong supporting, assistant grouting, fast digging, fast supporting, fast closing” was determined, and the horizontal jet reinforcement in tunnel was adopted when it was necessary. The proposed whole set construction method of such stratum conditions was explored and applied to the engineering practice successfully, which solved the rarely encountered engineering problem in the world. References | Related Articles | Metrics

Highway & Railway Engineering

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Methods about Using CatMull-Rom Spline to Describe Characteristics of Road Centerline in Perspective View Chen Yuren, Wang Ruiyun, Dong Yongjie, He Sihong 2015, 34(4): 45-51.  DOI: 10.3969/j.issn.1674-0696.2015.04.08 Abstract ( )   PDF (1680KB) ( )   Cubic Bezier spline, cubic B-spline and CatMull-Rom spline were used to fit road centerline in perspective view in this paper. The control points and fitting residuals from the three kinds of splines were analyzed by comparative studies. The results show that CatMull-Rom spline is more efficient and precise than the others in describing road centerline features in perspective view. It can meet the needs of describing features of perspective view from the vast maiority of road geometric design. The perspective view is divided into “near-scene”, “middle scene” and “far scene” as three different functional regions, and the concept and calculation method of the visual curve length and the visual curve curvature were proposed as shape parameters of road centerline in perspective view, combined the correlation analysis with operating speed. The shape parameters and operating speed are closely related. References | Related Articles | Metrics

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Mixture Proportion Design for Stone Mastic Asphalt Pavement Based on SkidResistance Performance Based on Skid-Resistance Performance Liu Yamin, Han Sen, Chen De 2015, 34(4): 52-56.  DOI: 10.3969/j.issn.1674-0696.2015.04.09 Abstract ( )   PDF (400KB) ( )   In order to study the skid-resistance performance of Stone Mastic Asphalt pavement (SMA) and provide advice for the mixture proportion design, several primary parameters in mixture proportion design for SMA, such as the percentage passing through the key sieve size and asphalt content, were taken as factors and the orthogonal experiment design was established. The effects of these factors on the skid resistance were studied and the typical gray correlation degree was introduced to quantify the influence of primary parameters on skid resistance. The results indicate that: with the increase of the percentage passing through the maximum size of aggregate and asphalt content, the skid-resistance performance of SMA is reduced; for the skidresistance performance of SMA-13, when the percentage passing through the sieve size of 9.5 mm grows, it is increased firstly and then decreased; the trend of the skid-resistance performance is contrary when the percentage passing through the sieve size of 4.75 mm is increased; for the sieve size of 2.36 mm, the skid-resistance performance is inclined to increase gradually; and with the increase of asphalt content, the skid-resistance performance of SMA is inclined to decrease gradually. The influence degree of various parameters on the skid resistance follows in a descending order as: the passing percentage of the maximum size of aggregate, percentage passing through the key sieve size, asphalt content, the percentage passing of maximum size of aggregate through the sub-tissue sieve size, the percentage passing through the subtissue sieve size. Finally, based on the above research results, the gradation range for SMA with better skid resistance is recommended. References | Related Articles | Metrics

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Potholes Measurement Method Based on Image Processing Without Reference Material Cao Jianqiu, Lan Quanxiang, Wang Danmei 2015, 34(4): 57-61.  DOI: 10.3969/j.issn.1674-0696.2015.04.10 Abstract ( )   PDF (626KB) ( )   A potholes measurement method without reference materials was proposed by researching the existing measuring methods. Firstly, the pothole images were photographed by using the Android devices, and then the direction and gravity parameters of it were utilized to preprocess and correct pothole images. Secondly, mathematical models to measure potholes were established and the formulas were calculated. Finally, the errors of the proposed method were analyzed. Experimental results show that the presented method can achieve high accuracy of measurement and its error is acceptable. Compared with the traditional measurement methods, the problem for relying on reference materials is solved, and it has low dependence on the environment; the more important thing is that the convenience of information collection is improved obviously. References | Related Articles | Metrics

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Influence of Reservoir Water Level Rise on the Stability of Super High Fills over V-shaped Gully Ding Jingsheng, Yuan Meng 2015, 34(4): 62-67.  DOI: 10.3969/j.issn.1674-0696.2015.04.11 Abstract ( )   PDF (1108KB) ( )   Natural fluctuation of water level has a great effect on the stability of super high fill in the Three Gorges Reservoir. With continuous rising of water levels, the water will actively infiltrate into the slope under the effect of pore water pressure and seepage flow in unsaturated soils. Firstly, based on seepage calculation theory, FLAC was applied to simulate the seepage field change of the Vshaped gully super high fill in the Three Gorges reservoir when the water level had been rising from 145m up to 155, 165, 175 m. Then, variation rules of important parameters including saturation, pore water pressure, horizontal displacement and maximum shear strain increment were analyzed. The relation between safety factors and different heights (150, 155, 160, 165, 170, 175 m) of rising of water level were researched in three working conditions, including rising of water level, rising of water level under 3D effect condition, rising of water level under 3D effect and two times as much as normal loads conditions. Eventually, calculation results show that: with water level continuously rising, the saturation of the fill increases, which will result in more concave saturated seepage line and higher pore water pressure; the safety factors of three kinds of working conditions are increased, up to the max level (175m), the stability safety factors reach the maximum. The change rate of safety factors decreases first and then increases. The water level rises up by each 5 m; the average safety factors increase about 5% in three working conditions. References | Related Articles | Metrics

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Comprehensive Risk Evaluation on the Longitudinal Cracks of Permafrost Subgrade Based on Fuzzy Neural Network Ye Min, Wang Tiequan 2015, 34(4): 68-72.  DOI: 10.3969/j.issn.1674-0696.2015.04.12 Abstract ( )   PDF (989KB) ( )   The natural environment factor, the design factor and the frost soil factor for the permafrost subgrade crack damage evaluation were selected as the input vector. According to the fuzzy rule, the nonlinear mapping relation of the longitudinal crack evaluation of subgrade was established. Through the combination of input pretreatment and output post treatment, the fuzzy rule was embedded into the nonlinear calculation of the neural network. It evaluated the longitudinal cracks risk degree in the section of K3+020 of QinghaiTibet Highway and the disk degree was defined as second grade based on 11 kinds of damage factors. The results show that the model can quickly, accurately and objectively evaluate the subgrade longitudinal cracks risk degree in permafrost regions. References | Related Articles | Metrics

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Roadbed Deflection Method of Beckmann-Beam Based on Double Rear Vehicle Chang Aiguo 2015, 34(4): 73-76.  DOI: 10.3969/j.issn.1674-0696.2015.04.13 Abstract ( )   PDF (682KB) ( )   The output of single rear vehicle (standard vehicle) has been decreased gradually. In order to make the roadbed deflection testing more perfect and reasonable, the common double rear vehicle was used to do test deflection, and the method of measuring was also discussed. And then the relationship of single or double rear vehicle deflections under the same roadbed were analyzed and contrasted. At last the roadbed deflection relationships between single and double rear vehicle were analyzed based on the theory of elastic semiinfinite body. The results show that: the double rear vehicle can be used in roadbed deflections detection, and the deflections between single and double rear vehicle are linear. References | Related Articles | Metrics

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Vehicle Dynamic Load Coefficient Analysis Based on Pavement Roughness Yang Chunfeng, Xie Shuai, Sun Jishu 2015, 34(4): 77-81.  DOI: 10.3969/j.issn.1674-0696.2015.04.14 Abstract ( )   PDF (581KB) ( )   In order to study the dynamic load effect of vehicle running on uneven pavement further, a quarter-vehicle vibration model was applied to analyze the influence law of dynamic load coefficient based on the pavement roughness, vehicle parameters and other factors by using MATLAB software. Calculation result indicates that speed and the road surface amplitude have a great influence on the dynamic load coefficient, and pavement amplitude has a linear relationship with dynamic load coefficient. It is also indicated that the main cause of the dynamic load is pavement roughness; tire damping, suspension stiffness and suspension damping have less impact on the dynamic load coefficient than others, meanwhile, to reduce the tire stiffness can significantly reduce the dynamic load. From the view point of road design, to improve the road roughness is an important measure to reduce the dynamic load. References | Related Articles | Metrics

Port & Waterway ? Hydraulic & Hydroelectric ? Resources & Environment

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Study on the Effect of Different Constraint Condition at Pile Bottom on Internal Force Distribution of Arc Row Piles with Arc Coupling Beam Internal Force Distribution of Arc Row Piles with Arc Coupling Beam Zhang Zhiwei，Deng Ronggui，Wang Zhenyong，Zhong Zhibin 2015, 34(4): 82-87.  DOI: 10.3969/j.issn.1674-0696.2015.04.15 Abstract ( )   PDF (683KB) ( )   The model for arc coupling beam can be simplified as hingeless arch, according to the high order statically indeterminate characteristics of the spatial antislide structure, with the redundant forces between beam and pile top, by using deformation compatibility to set up flexibility equation of new spatial antislide structure. Based on the different constraint conditions such as freedom, hinge and fixation at the pile bottom to solve the redundant forces, then calculate and compare the internal force of arc coupling beam and the internal force and displacement of pile among the different constraint conditions at the pile bottom, and the influence law of internal force and displacement by different constraint conditions was obtained. That the moment at the bottom of pile is larger as fixed, but reduce obviously as free and displacement increase. By the constraint of coupling beam, shortening the length of anchoring section can reduce the moment at the bottom of pile. References | Related Articles | Metrics

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Security Warning Measures of Shiplift Docked with Approach in Unsteady Flow Li Zhonghua, , Hu Ya’an, 2015, 34(4): 88-90.  DOI: 10.3969/j.issn.1674-0696.2015.04.16 Abstract ( )   PDF (901KB) ( )   The water level fluctuation transferring rules of the TGP shiplift downstream channel between approach entrance and chamber were simulated by 2D numerical model in various downstream water level, fluctuation amplitude and cycle. The relation of the TGP shiplift downstream water level fluctuation between approach entrance and ship chamber was established. Based on the water level fluctuation transfer relation, a new security warning measurement was proposed by monitoring approach entrance water level to reduce the risk of the TGP shiplift chamber docked with downstream approach in unsteady flow. References | Related Articles | Metrics

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Numerical Modeling of Preferential Flow and Transport Channel between RoughWalled Fractures between Rough-Walled Fractures Yu Cheng, Lei Wenwu 2015, 34(4): 91-95.  DOI: 10.3969/j.issn.1674-0696.2015.04.17 Abstract ( )   PDF (758KB) ( )   In order to show the impact of non-uniform void space on the flow and transport processes between rough-walled fractures, LCL modeling was employed to simulate the process of the solute transport under the flow with different crack width. The result suggests that, along with the decrease of fracture apertures, the flow field tends to get irregular, and streamlines tend to concentrate at preferential flow channels. Solute concentration front looks parallel when the fracture aperture is still significant, but gets irregular and looks similar to finger flow while fracture aperture decreases. As apertures decrease, preferential channels tend to form preferential transport channels. Solute transport speed at preferential transport channels tends to be much higher, thus some of the solute at low permeable regions seems to be trapped, or retarded within fractures. Therefore it can be concluded that when fracture apertures are small, preferential channels have significant impact on flow and transport processes between rough fractures. References | Related Articles | Metrics

Transportation Engineering

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Effects of Street Trees Porosity on Traffic Noise Reduction Hu Xisheng, Zheng Yan, Chen Min, Wei Huayun, Ye Limin, Qiu Rongzu 2015, 34(4): 96-99.  DOI: 10.3969/j.issn.1674-0696.2015.04.18 Abstract ( )   PDF (499KB) ( )   Digital camera was used to take pictures of street trees, and Photoshop software was used to calculate the green belt porosity. Based on the data, the relationships of green belt porosity and traffic noise reduction were analyzed. The results showed that the green belt porosity of Yangqiao Middle Road, Wusi Road, Bayiqi Road, Shangxiadian Road, Industry Road and North Riverside Road were 0.683, 0.752, 0.600, 0.767, 0.909 and 0.787 respectively. The porosity sequences of street trees were as follows: Cinnamomum camphora (childhood), Bombax ceiba, Bauhinia purpurea, Mangifera indica, Ficus microcarpa and Cinnamomum camphora (adult). The relationships between the street tree porosity of layer A and the traffic noise reduction were obviously negative. This study provides an important theoretical foundation and practical reference for the configuration of street trees. References | Related Articles | Metrics

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Information Acquisition of Expressway Drivers in Snowstorm Weather Zhang Xuguang, Gao Jianping, Wu Guoxiong 2015, 34(4): 100-103.  DOI: 10.3969/j.issn.1674-0696.2015.04.19