bluuebunny/crossref_metadata_2025 huggingface dataset:
Local Stress Analysis and Corner Radius Optimization of PPSCB
Authors: Huang Wen Xiong , Tan Li Ying
Published: September 2013

To research the local stress state of the polyline pretensioned beams, the 3-D nonlinear finite element model is established by FEA software ANASYS. The results show that the existence of the inflection point on the prestressed reinforcement is the main reason of local stress distribution, and the corner radius R is the primary influential factor of the local stress distribution phenomenon. Then, the variation law of the stress and stress distribution by the corner radius R is illustrated clearly. With the increasing of R, the maximum local stress has decreased, and the stress distribution curve has increasingly become smoothly and gently. Considered the variation law of local stress and various of construction requirement in engineering practice, R=600mm is selected as the optimal radius.
Construction Technology of Super-Deep Diaphragm Wall under Complicated Geological and Hydraulic Conditions
Authors: Yang Bao Zhu , Zhang Shu Chao
Published: September 2013

Supper-deep diaphragm wall construction of a Tianjin traffic hub project penetrated through many soil layers and two layers of confined water, geological and hydraulic conditions were complicated. Some special technologies including grooving methods,anti-collapse measures,verticality controlling measures, joint treatment measures and steel reinforcement cage hoisting measures were adopted for the construction. The project was finished with short time, low cost and good quality. Engineering practice shows that these technologies were appropriate for constructing supper-deep diaphragm wall under complicated geological and hydraulic conditions. These experiences can give some references to the similar super-deep diaphragm wall construction of Tianjin and other regions in future.
Study on Stability of Loess Tunnel Based on Three-Dimensional Numerical Simulation in Different Excavation Length of Invert
Authors: Sun Zhi Jie , Shen Jun Min , Xue Xiao Hui , Su Zhong Ming
Published: September 2013

The 3D finite element simulation was adopted to study the globality stability of tunnel caused by the different excavation length of invert. Kelan-Linxian highway loess tunnels were taken as an example. The research results are shown as follows: The vertical displacement and horizontal convergence increased by the increasing of the excavation length of the invert. But the latter increase range is larger than the former. The horizontal convergence in sidewall is convergence value is greater than the level of the arch and the corner, the horizontal displacement primarily occurred in the side wall position. The surrounding rocks maximum plastic strain occurred in side wall and corner wall in 4 working conditions. The plastic zone occurred around from arch corner to wall side. In Tab. 4, the maximum plastic strain is increased by the excavation length of inverts increasing.
Finite Element Analysis for the Stress Field and Seepage Field Interaction within Qingdao Submarine Tunnel Rockmass
Authors: Li Cheng , Zhou Tai Quan , Jiang Sha Sha , Kong Jie
Published: September 2013

The submarine geology characteristic for Qingdao submarine tunnel is fracture and fragmentation with smash rock mass and unevenly distributed rock mass strength. The submarine tunnel is excavated in a weathered rock mass containing water. Before the tunnel lining is constructed, it is important to assure the stability and safety for the rock tunnel and tunnel lining structure during construction and operational periods. As the submarine tunnel is under severe condition, the rock mass stabilization is to a large extent to be determined by the underwater seepage effect. It is fundamental to investigate how the seawater interacts with the tunnel rock mass stress field. To investigate the interaction between the rock mass seepage field and the secondary stress field, the nonlinear finite element software ABAQUS is used to analyze the interaction behavior between the rock mass seepage effect and the tunnel secondary stress field. The rock mass seepage field, stress field are analyzed in detail using the numerical simulation method. Also, the distribution of the tunnel rock mass plastic region is obtained. The numerical analysis results provide guidance for the submarine tunnel construction.
Numerical Analysis on Influence of Cross Section Shape on Earthquake Resistant Capability of Shallow-Buried Tunnel
Authors: Xie Hong Tao
Published: September 2013

Taking portal segment in some shallow-buried tunnel in seismic region with strong motion as objects of study, the finite element analysis method was used to compare and assess the seismic behavior of the tunnel with different cross section shape. The results show that the linings displacement response of the tunnel with different cross section shape differs very minor under seismic load. Meanwhile there exists obvious difference in the lining internal forces of the tunnel with different cross section shape. Among all the tunnel with different section shape, the mechanics situation of the tunnel with triple arched sections is the best. While the section of the tunnel is closer to circular in shape, the mechanics situation of the lining can be effectively improved under seismic load.
Study on Construction Risk Assessment Method of Deep Buried Tunnels
Authors: Kuang Xing , Yi Di Qing , Wang Cheng Liang
Published: September 2013

High speed railway tunnel have many uncertainty hazard factors in construction, at the stage of construction drawing design and during tunnel construction process. Taking no.1 tunnel in Xuefeng Mountain as a deep buried tunnel in the paper, tunnel construction risk source and main risk identification are analysis, main risk assessment during construction is recognized and reference for other similar projects is provided.
Application Analysis of Comprehensive Advanced Geological Prediction in Karst Tunnel
Authors: Wang Cheng Liang , Bai Ming Zhou , Du Yan Qing , Kuang Xing
Published: September 2013

Based on the DaDu mountain tunnel of new construction ShangHai-KunMing high-speed railway, combine with field geology investigation of the tunnel address area comparative analysis TRT advanced geological prediction, infrared probe water, ground penetrating radar advance geological forecasting and tunnel design data, aimed at fault fracture zone, high-pressure water-rich belt, the karst fissures developmental situation may have in construction period of DaDu mountain tunnel, carried out the comprehensive advanced geological prediction and then combined with the actual excavation situation contrast and verify the feasibility and practicality of the comprehensive geological advanced prediction technology, and it will have important significance of reference for the similar tunnel project in design and construction period.
Application of "Rigid-Soft Combination" Principle in Waterproof of Tunnel
Authors: Lin Zhen Rong , Lai Yuan
Published: September 2013

The waterproofing is the most essential technical specification and the difficult problem in civil engineering specially in the water draining water construction and the tunnel. Formerly, we used guard against infiltrate the concrete or in guard against the aqueous phase union with the outside waterproofing two defense lines, the effect actually not entirely as desired. In this paper, through combining engineering practice, raise a processing project of tunnel waterproofing constructions, based on the rigid-soft combination principle.
Surface Settlement Time Lag Induced by Shield Tunneling in Urban Sandy-Pebble Stratum
Authors: Man Shuai
Published: September 2013

This paper focuses on the surface settlement time lag caused by shield tunneling in sandy-pebble stratum in Chengdu. A surface collapse case during Chengdu metro construction was introduced and the mechanism of surface settlement time lag was analyzed. The process of the ground settlement was simulated using the UDEC software. It is found that: 1) over-excavation and the grouting failure are the root causes of surface settlement; 2) characteristics of the sandy-pebble stratum in Chengdu induce ground voids behind tunnel segmental lining; 3) the mechanism of surface settlement time lag can be explained by temporary ground arch in the sandy-pebble stratum.
The Comparison of Tunnel Engineering Construction Methods for Renhechang Tunnel Crossing Underneath Existing Tunnel on Lanzhou-Chongqing Railway
Authors: Sui Chuan Yi , Zhou Xu Dong , Wang Lin Hui
Published: September 2013

Problems often exist in construction of transportation tunnels, such as the effect of new tunnels constructed close to existing structures. Solving this magnificent problem by carefully choosing tunnel construction methods will be beneficial to minimize effects on existing structures while ensuring the newly constructed tunnel is both time-consuming and economical. Three representative engineering methods-the benching tunneling method, the Center Diaphragm method and the Cross Diaphragm method-are compared in controlling the settlement of new tunnel vault and the deformation of the existing tunnel. Finally checking the simulation results by comparing with field measurement data.
Numerical Simulation for Surface Displacement of Shield Tunnel Construction under Building Load
Authors: Zhan Hui Ting , Yuan Hong , Wu Jia Yu , Yuan Yu Sen
Published: September 2013

The tunnel construction causes deformation, even damage of the nearby buildings and other types of structures. Using 3d finite element method can simulate the process of shield tunneling construction. The paper studies the influence of different building load on the deformation of soil, when considering different excavation steps in the process of tunnel construction. The results show that the building load has important influence on the surface displacement during the construction of tunnel. With the advancement of excavation, sedimentation tank will move forward and become larger. By the influence of jacking force, the soil and rock in front of tunnel face moves forward and upward, thus forming the surface uplift.
Experimental Study on Mutual Effects of Rock Tunneling Positions with High Underground Pressures
Authors: Gao Quan Chen , Lei Cheng Xiang , Liang Ming , Zhao Hua Shuai
Published: September 2013

Using the mould pattern contrasting experiments the carrying capacities and deformation effects of underground tunnels within soft bed and top or floor strata are studied under high ground pressures in this paper. Through measuring mould strengths and deformation with different stratum and space position the relations of tunneling positions in different strata with carrying capacity and strains are obtained. It is shown that the soft seam tunneling under high ground pressure can bring about higher secondary stresses and have more acting effects than top or floor tunnels. In the same pressure conditions the carrying capacity of having top tunneling above soft tunnel decreases near 30% with that of having floor tunnel. The mutual effects with double horizontal spaces of tunnels decrease 25%. The experiment conclusions are important significance of conducting and applying for reasonable designing underground tunneling engineering.
Study on Failure Mode of Underground Diaphragm Wall in Soft Soil Area
Authors: Zhang Shi Min , Li Xiang , Li Deng Hui , Ding Zhi , Wei Gang
Published: September 2013

Zhejiang Province is Located in the Yangtze River Delta which the Soft Soil has Large Thickness and the High Underground Water Level.There is a Higher Requirement for the Optimization Design and Safety Construction of Deep Foundation.According to the Summary and Analysis of some Common Cause Failure of the Foundation Pit Engineering，we can Conclude that there are some Failure Mode in Soft Soil Area of Underground Diaphragm Wall Structure such as Foundation Pit System Instability，Basal Failure，Piping and the Flow of Sand Damage，Support Structure Instability and the Support of Low Strength or Buckling，and Summarizes some Prevention Measures on the Destruction of Underground Diaphragm Wall in the Light of these Failure Modes.
Multiple Compaction Tests on Laterite
Authors: Wang Rui Ying , Wang Qing , Gao Ying , Bao Shuo Chao , Li Zheng Wei , Zhang Ying , Xu Peng
Published: September 2013

Laterite has high void ratio, low density, high moisture content, high plasticity, but it does not match with their physical nature, which has the relatively high strength and low compressibility. In order to improve the strength of laterite and increase its compactness, we usually use the method of dynamic compaction in some large engineering projects. Its easy to find that soil compaction degree increased with the moisture content When the content of moisture is low, but soil compaction decreased after reaching the highest. Multiple compaction can effectively improve the maximum dry density and reduce optimum moisture content, but after compaction number is too much that optimum moisture content dont increase obviously.
Method to Determine the Navigable Depth by Rheological Properties
Authors: Ying Qiang , Jiao Zhi Bin , Wan Jun , Yuan Sheng Ying
Published: September 2013

The navigable depth, affecting economic value, needs to be determined in ports and waterways with thickness of silt layer. Through the studies of silt samples, it is found that the relationship between viscosity and specific weight follows the cubic polynomial equations. A new method is proposed for determining the navigable Specific Weight, that is, the same increment of the viscosity and the specific weight () is regarded as the judgment condition for the navigable Specific Weight.
Reliability of the Offshore Jacket Platform Based on Load Combination
Authors: Shen Zhao Wei , Jin Wei Liang , Wang Xiao Hong
Published: September 2013

Offshore jacket platforms under complicated and changeful ocean environments are subjected to various stochastic actions such as actions of wave, current, wind, ice, earthquake and their combinations. This paper presented the approach to calibrate of the reliability of the offshore jacket platform, and suggested all kinds of associated load cases. The combination of loads were mainly investigated. As an example, the reliability of offshore jacket platform of QK18-1 in Bohai Bay was verified. The result shows that the reliability of the offshore jacket platform related to 25-year reference period is between 2.7 and 3.39, which is close to the conclusion of some existing researches. This method would be used more widely for the design of offshore jacket platforms.
Research of the Artificial Island Construction Impact on Marine Deposit Dynamic Environment
Authors: Wang Ying , Li Xin , Li Ming Chang
Published: September 2013

The article analyses and predicts the hydrodynamic feature of Tang Shan bay on the basis of Ecomsed model, thus the calculation accuracy is improved. And then it predicts erosion-deposition characteristics of the study sea area.The paper assesses the influence of the artificial island construction in aspects of hydrodynamic and erosion-deposition environment. Research shows that the sea area in the north of the artificial island is deposition area because of sand excavation and the water inside is slightly deposit.
Seafloor Slope Stability under Adverse Conditions Using Energy Approach
Authors: Nian Ting Kai , Liu Bo , Yin Ping
Published: September 2013

The effects of ocean waves on the stability of seafloor slopes are of great importance in marine environment. The stability of a seafloor slope considering wave-induced pressure is analyzed using the kinematic approach of limit analysis combined with a strength reduction technique. A seafloor slope without waves is considered first. Furthermore, waved-induced pressure is considered to act on the surface of slope as an external load to analyze the effects on the stability of slope by waves. The results show that the adverse effect of waves on slope stability increases with an increase of the wave height as well as a decrease of the water depth.
Aerodynamic Stability of a Three-Tower Suspension Bridge during Erection via Aeroelastic Model Test
Authors: Zhang Wen Ming , Ge Yao Jun
Published: September 2013

As a new long-span suspension bridge with double main spans and a typical closed streamline cross-section of single box deck, the flutter performance of the Maanshan Bridge during erection was investigated via a full bridge aeroelastic model test. Critical flutter wind speeds of 13 testing cases with different percentage of deck completion are much higher than the flutter checking wind speeds, and the bridge is hence proven to be stable enough during erection in aerodynamics. The case with the percentage of deck completion of 86.4% gets the lowest flutter critical wind speed, perhaps because frequency ratio gets the minimum value at this case.
Study on External Prestressing Connection Mode of the Simply-Supported and Continued Structure System
Authors: Jiang Xiu Juan , Li Rong Da , Wu Jun Yan , Liu Jian Xin
Published: September 2013

Simply supported beam by applying the external prestressing change as a continuous system can be a substantial increase in the bridge carrying capacity, but more complex in vitro beam connection segment force. To study the forced state of external prestressing connection mode of the simply-supported and continued structure system, it is studied by both the way of numerical simulation using the finite element analysis software ANSYS and experimental research. The physical model to simulate the prestressed concrete structure and the test process are described. By comparing the results of numerical simulation and experimental research, the stress stage of the connection mode is divided. As a result, a simplified method of calculating the deflection based on the elastic theory is proposed. The internal force redistribution of the structure is also determined. The results of the numerical simulation method are reliable because it is similar to measured results.
Transverse Analysis of Box-Girder for Continuous Beam Arch Composite Railway Bridge
Authors: Yu Xiang Dong , Wu Zhi Hua
Published: September 2013

A comparative study was carried out by establishing an overall bridge spatial finite element model and a transverse frame model on transverse structural characteristics of Kunyang Bridge on Wenzhou-Fuzhou Railway line. The longitudinal variation of transverse stress in box-girder shows peaks distribution. The absolute values of transverse stress decrease gradually at peaks and valleys in overall tendency as it’s close to the mid span. The calculation results of the rigid support frame method can envelop the calculation results of the overall bridge spatial finite element model in side span region without suspenders.It verifies the reasonability of the rigid support frame method to calculate transverse stress of this region. And the width of transverse frame should designate one third of suspender spacing or more in transverse stress calculations of central span region with suspenders.
Study on Running Performance of Train and Limit Value of Traffic Safety on Hubian Bridge
Authors: Jang Bo , Zhou Zhi Hui , Liu Guo , Zeng Qing Yuan
Published: September 2013

The running performance of train on Hubian bridge was analyzed with energy random analysis theory for derailment. The calculated result shows that the running safety of train cannot be ensured with the existing operation condition, and the measurement of rate-limiting or reinforcement is needed to be taken for this bridge. A method for establishing index of traffic safety for railway bridge was proposed. The detailed contents of the method are as follows. The lateral amplitude on the middle of beam is determined as index for traffic safety for beam-pier system. The critical beam-pier system with which the running performance of train can be guaranteed is determined. The lateral amplitude of critical beam-pier system is calculated and determined as limit value for traffic safety. The limit value of lateral amplitude for traffic safety for Hubian bridge is determined as L/6400.
The General Review of Permafrost Temperature Research Methods
Authors: Lin Zeng Hua , Zhang Yan Hui
Published: September 2013

Freezing soil is a natural phenomena in cold and mountain areas, which has great impact to the regional climate, water cycle, water balance and human activities. Permafrost against the 100 years of research show that the soil is frozen soil temperature, moisture and stress fields of common effects. Permafrost temperatures ranged from permafrost in the unique position of permafrost temperature permafrost research has become an important part of research, this paper introduces the permafrost temperature domestic development theory and research status, from the approximate calculation of the numerical analysis, measured from the scene of the computer simulation analysis, from one-dimensional to multi-dimensional theory of expansion. Permafrost temperature while the influence of the analysis, expounded the permafrost temperature on moisture movement for the promotion and transfer of water temperature counterproductive. Permafrost temperatures also study the mathematical description of the problem of note, citing the current use of the important research methods. A brief description of the permafrost study the problems that exist.
Calculation and Analysis of Continuous Welded Rail on Continuous Rigid Frame Bridge
Authors: Yan Le , Wang Yu , Wang Ping , Hao Liu
Published: September 2013

At present, China's large span continuous rigid frame bridge (CRFB) has made rapid development, and has been applied in the railway bridges. This paper based on finite element analysis software ANSYS, using the simplified algorithm, establish a line - bridge - pier integration model for calculation of continuous welded rail (CWR) on bridge, the continuous rigid bridge and continuous rigid frame bridge (CGB) in two different conditions were compared and analyzed. The calculation results show that: the rail expansion force, bending force, braking force, rail broken gap of CRFB are smaller than that of the CGB of same beam span, in CWR, CRFB has obvious advantages, it should be popularized.; equivalent temperature span of CRFB are smaller than that of the CGB of same beam span, so the CRFB is less affected by the temperature; because of the pier and girder consolidation of CRFB, favorable to CWR, but due to the bending effect of bridge piers can lead to beam produces larger vertical deformation, thus affecting the track smoothness, which must be noticed in design.
The Practice of Concrete Filled Steel Tube Piers to Bridges: A Review
Authors: Ou Zhi Jing
Published: September 2013

Due to the small section dimension, high compressive strength, large stiffness, and excellent deformation capacity, the use of concrete filled steel tube (CFST) piers is attractive, especially to high-pier and super-high-pier bridges located in mountains. This paper reviews available information concerning the application and development of CFST piers. Three bridge examples are then introduced, while the structural design and the construction methods of CFST column piers are described in detail. Furthermore, main parameters of CFST piers, such as slenderness ratio and material strength are concluded. Finally the future research direction of CFST column piers is viewed.
Analysis and Test on Mechanical Properties of a Flexible Suspension Bridge
Authors: Cao Guo Hui , Hu Jia Xing , Zhang Kai , He Min
Published: September 2013

In order to research on mechanical properties of flexible suspension bridges, a geometric nonlinear analysis method was used to simulate on the experimental results, and carried on static loading test finally. In the loading test process, the deformations were measured in critical section of the suspension bridge, and displacement values of measured are compared with simulation values of the finite element simulation. Meanwhile the deformations of the main cable sag are observed under classification loading, the results show that the main cable sag increment is basically linear relationship with the increment of mid-span loading and tension from 3L/8 and 5L/8 to L/2 section, the main cable that increasing unit sag required mid-span loads and tension are gradually reduce in near L/4 and 3L/4 sections and gradually increase in near L/8 and 7L/8 sections and almost equal in near L/2, 3L/8 and 5L/8 sections. From the experimental results, the flexible suspension bridge possess good mechanical properties.
Research on Modal Identification Method of Pre-Stressed Concrete Bridge
Authors: Jiang Hao , Meng Guang Wei , Zhang Hai Kuo
Published: September 2013

To study validity of power spectrum density peak method which be used to identified modal parameter of concrete bridge under ambient excitation, number simulation of one Pre-stressed concrete bridge is carried out.3D model of the bridge is established by FEM software , FEM analysis and time-history analysis of 3D model of PC continuous beam bridge are carried out.During the simulation,practical factors such as acceleration measuring and white noise are taken into account. In the only case of the output signal modal parameter of bridge can be identified. Six-order modal parameters of the structure are identified by the number simulation which the average error is less than 5%. It is revealed that power spectrum density peak method is suitable for bridges monitoring and diagnosis, with important practical engineering application value.
Research on the Effect of Width-Span Ratio on the Bridge Impact Coefficient
Authors: Qi Chun Xiang , Gao Yu Huan , An Qing Zhang
Published: September 2013

In this paper, the bridge impact coefficient was researched under conditions of the same section form and different width-span ratio. Five bridge models were set up based on the finite element method. Static and dynamic load simulation analysis for the same form of bridge was conducted firstly. Then the impact coefficient was calculated. Finally, According to the variation of impact coefficient along with the bridge width-span ratio, the method of probabilistic statistical regression analysis is applied to analyze the changing rule of the impact coefficient change with width-span ratio. Results showed that the influence of width-span ratio on impact coefficient should considered preferably for ordinary highway bridges with its width-span ratio less than 1. But for taxiway bridges which the width-span ratio is generally between 2 to 3, the influence of width-span ratio on impact coefficient can be ignored.
Dynamic P-Δ Effect on Probabilistic Residual Displacement of Bridge Structures
Authors: Yu Bo , Liu Di , Yang Lu Feng
Published: September 2013

Residual displacement has been identified as one of the most important parameter to assess the reparability and usability of bridge structures after strong earthquake, which is significantly impacted by the P-Δ effect. In this study, the influence of the P-Δ effect on the probabilistic characteristics of residual displacement of bridge structure was quantificationally investigated based on a series of nonlinear time-history analysis. The bridge structure was idealized as the single-degree-of-freedom (SDOF) system and the hysteretic behaviour was represented by the improved Bouc-Wen model. The statistic analysis was implemented based on the inelastic dynamic responses of the SDOF system under 69 selected earthquake records. The results show that the P-Δ effect has significant impact on the residual displacement, especially for systems with large stability factor and/or small post-yield stiffness ratio and yield strength.
Sequence of Urban Bridge Maintenance and Repair Based on Multiple Factors
Authors: Huang Fang , Chen Zhang
Published: September 2013

With the bridge maintenance reinforced gradual increase in demand, the maintenance and repair of bridges and related facilities need to spend a lot of money. And the bridge of the limit line, weight limit, demolition and reconstruction measures will have a significant impact on traffic. Therefore, bridge maintenance decisions had become a problem faced by the facilities management department. In the case of limited funds, how can we determine the order of bridge repair and reinforcement, take the maintenance of the extent to which the urgent need for a systematic, efficient and practical method to develop optimal bridge maintenance and repair strategies to ensure that high-risk bridge timely conservation maintenance. This paper proposes a method of bridge maintenance and repair ranking The paper analyze a multivariate method, get result of multivariate, and verify the feasibility of the approach by using an example.
Reliability Assessment of Existing Reinforced Concrete Arch Bridge
Authors: Peng Wei , Ye Wen Ya , Jia Jia , Lu Zhao Hui , Hou Hai Tao
Published: September 2013

A finite element model of an existing reinforced concrete arch bridge was established. The reliability index was investigated based on the PDF module in ANSYS software. Taking the maximum concrete stress and tendon stress as limit state, the limit state functions of main arch, upright column and deck are established respectively. There are taken as series system to study the bridge system reliability according to the structural characteristics of reinforced concrete arch bridge. The lowest reliability index superstructure is selected as the whole structure reliability index. Based on JC method and made-up MATLAB program, the reliability index of the example bridge is calculated.
Cable Force Optimization Method in Two Stages for Spatial Cables
Authors: Huang Hai Xin , Zhang Ying , Cheng Shou Shan , Li Fan
Published: September 2013

To get the ideal cable forces of the arch bridge with spatial oblique cables,Rigid Support Continuous Beam Method and Rigid Suspender Method are discussed.The results show that the former is unsuitable for the spatial structure with smaller horizontal stiffness,and the latter does not consider the elastic deformations of the cables.An improved cable force optimization method is provided,which takes Rigid Suspender Method as the initial stage to obtain initial cable forces and takes Influence Matrix Method as the subsequent stage for cable force increments.The method by test is proved to be effective to spatial structure and nonlinear structure with spatial cables.
Technological Study on Interlayer Bonding of Double-Layer Porous Asphalt Pavement
Authors: Tang Guo Qi , Cao Dong Wei , Zhong Ke , Yang Xiao Qiang
Published: September 2013

The interlayer bonding of double-layer porous asphalt pavement will show more variations with different construction technologies, such as one-step molding by double-layer (hot on hot) paver, or paving layer by layer (hot on cold) with or without tack coat, and the variations will definitely have influences on pavement structure. Different interlayer technologies are studied in this paper on three levels including simulation experiments on specimen by indoor preparation, calculation of pavement mechanics, and construction of testing road, so that optimal interlayer bonding technology for double-layer porous asphalt pavement is discussed in combination with its effect on permeability.
The Design and Implementation of Roadworks Management System Based on GIS
Authors: Zhang You Heng , Su Bao Bing
Published: September 2013

Most of current construction project management software focus on text, quantity information and lack of engineering graphics, display, query and analysis of features and other spatial features. In order to solve these problems, GIS is taken as the core, Multipatch programming is used in the natural ground and roadbed, drawing 2D features are stretched for 3D visualization and dynamic 3D display of construction progress. The TIN model is constructed and the main spatial analysis functions are implemented, including the query of 3D point information, the query of longitudinal section, cross section, volume, surface area as so on at any position. A road engineering construction management system is developed in Microsoft Visual Studio2010 platform using c # 4.0 language, the GIS secondary development tools ArcGIS Engine9.3 and Microsoft Access2007 database. GIS is taken as the core in basic framework of the system, the system has a certain application prospect in the road construction management.
Mechanism Analysis of Emulsified Asphalt Cold Recycled Mixture
Authors: Jiang He
Published: September 2013

In this paper, the electrical analysis of emulsified asphalt and aggregate explains the reaction mechanism of the emulsified asphalt and aggregate. When emulsified asphalt and wet mineral aggregate contact each other, asphalt particles with a charge have chemical adsorption with aggregate at the surface of mineral aggregate, and asphalt particles are arranged on the surface of later quickly. Subsequently, asphalt of recycled mixture can be more cohesive after a series of process between emulsion and aggregate, such as demulsification and drying by distillation. A compact structure is formed by asphalt wrapping aggregate to make recycled mixture high strength. The mole - coulomb theory analyzes formation principle of emulsified asphalt cold recycled mixture strength. The strength of the recycled mixture mainly depends on the cohesion and internal friction among materials. In early stages, asphalt can not bonding because of water, which reduce the friction resistance of recycled mixture, and lead to the early strength of recycled mixture is small. After curing, the recycled mixture has the similar structure like hot asphalt mixture, which the cohesion and frictional resistance of recycled mixture became strong and the strength increased greatly. Besides, this paper expounds the dual role of cement that hydration reaction and of being active mineral powder in the process of emulsified asphalt cold recycled mixture strength formation.
Existing Railway Horizontal Alignment Reconstruction Algorithm Based on Line Segments Identification
Authors: Liu Wei , Wang Jian Hong , Li Yang , Li Wei
Published: September 2013

A Line Segments Identification model is put forward to realize the existing railway horizontal alignment reconstruction. Firstly, Hough transform based on constraint adjustment quantity is introduced to reject the abnormal points that will affect the quality of the identification in latter steps. Then total least square method is used to get the linear segments, after which the circular curve segments and the transition curves segments will be got. At last, an evaluation function which has four arguments: circular curve radius , two transition curves length and length of straight line between curves was built and its function value is the sum of squares of all distances from measuring points to reconstruction alignment, based on the function , optimal alignment will be solved out by Powell method. Example shows that the reconstruction result is considerably superior to the traditional method and is feasible for the engineering practice.
Experimental Study on Hydrodynamic Pressure Generated by Sleeper Loose
Authors: Su Cheng Guang , Hong Kang , Li Yao Dong , Yang Rong Shan
Published: September 2013

Through indoor simulation test of double-block ballastless track sleeper loose hydrodynamic pressure, this paper study the variation laws of hydrodynamic pressure of different position, different load and frequency variation. The results show: The location of the biggest hydrodynamic pressure is in the middle of the crack and near the not void area. The amplitude and frequency of load have obvious influence on the hydrodynamic pressure. When the load amplitude is more than 30kN or load frequency exceeds 10HZ, the effect on the hydrodynamic pressure is particularly notable.
Compaction Temperature's Influence on the Pavement Performance of Warm Asphalt Mix with Different Matrix
Authors: Zhu Guang Shan , Yu Ling
Published: September 2013

Warm mix asphalt (WMA) is a new type of asphalt mixture that uses a special additive to reduce mixing temperature and compaction temperature to realize energy saving and environmental protection purpose. Laboratory tests are conducted to study that, at different compaction temperatures, the air void rate, dynamic stability and change rule of flexural-tensile strain of the Sasobit WMA of 3 matrix asphalts (Liaohe70#, Liaohe90#, Karamay90#). The results show that when compaction temperature rises, air void rate decreases and the degree of decrease turns slow. At the same temperature, WMA of Karamay90# added with 3% of Sasobit (K90S) has the least air void rate. Along with the rising of the compaction temperature, dynamic stability increases in linearity. At the same temperature, WMA of Liaohe90# added with 3% of Sasobit (L90S) has the best dynamic stability. 115°C is the optimal compaction temperature for L70S and K90S to keep relatively high flexural-tensile strain. At the same compaction temperature, difference of flexural-tensile strain is small among 3 matrix asphalts.
Experimental Study on Earth Pressure of Corrugated Steel Culvert under High Fill Embankment
Authors: Yu Wen Sheng , Li Zhu Long , Xie Xiao Ru , Guo Li Yuan
Published: September 2013

To analyze the earth pressure of corrugated steel culvert under high fill embankment, a field test was taken and the change law was got with the filling height increasing, the force state when geotechnical grilles were laid on the top of corrugated steel culvert was compared to that of reinforced concrete slab culvert. Results show that the pressure on the top of corrugated steel culvert is smaller than that on the external in same level when test points are near to culvert, the values of test points above and below geotechnical grilles are close, and the pressure of corrugated steel culvert is smaller than that of reinforced concrete slab culvert when filling height is above 7.3 m. So analysis indicates corrugated steel culvert spreads the upper load better, the geotechnical grille can reduce the pressure effectively through earth pressure redistribution, and the mechanical property of corrugated steel culvert is better than reinforced concrete slab culvert under high fill embankment.
Decision-Making Method of Maintenance Scheme for Highway Asphalt Pavement
Authors: Gao Shun Ping , Wu Pei Guan , Feng Jian
Published: September 2013

established the evaluation index according to the influencing factors (the road grade, traffic volume, road conditions, the strength of pavement, pavement performance and anti-sliding ability, etc) of highway asphalt pavement maintenance scheme. According to the interrelation of the various indexes, I put forward a set of method about the maintenance of the highway asphalt pavement.
Analysis of Cement Emulsified Asphalt Mortar Gap on CRTSII Slab Track under Train Loading
Authors: Xu Hao , Wang Ping , Xu Jing Mang
Published: September 2013

The finite element method was used to analyze the deformation and stress of track in different length and height of gaps under the train load. In order to study the influence of gap between the slab and emulsified cement asphalt mortar of china railway track system II slab track on the subgrade, a model of CRTS II slab track was established on the base of elastic foundation beam theory and finite element software ANSYS. The results show that gap between slab and CA mortar has significance effect on the stress and deformation of track structure. The deformation of rail and slab, the longitudinal stress of slab were increase with the increase of gap length, but has less effect on lateral stress of slab. When the length of gap exceed to 1.95m, the deformation and stress have the tendency of increase sharply, the length of gap between slab and CA mortar should not exceed 1.95m. The gap between slab and CA mortar has effect on the durability and lifetime of ballastless track, so the gap should be maintenance timely.
Dynamic Analysis of Railway Vehicle Moving through Bridge with Varying Velocity
Authors: Zhu Huai Liang , Wang Xue , Yu Li Feng
Published: September 2013

A dynamic model of vehicle-bridge interaction is presented considering the railway vehicle moving through bridge with varying velocity. Assuming the vehicle has a constant acceleration, the motion equations of coupled vehicle-bridge system were deduced based on DAlemberts principle and theory of Euler beam. Dynamic responses of system were analyzed both cases of the acceleration and drag acceleration for a moving car. Results show that the amplitudes of vibration of the system will enlarge sharply with the acceleration of vehicle increasing, and the maximum of responses occur when the vehicle moving at the middle point of bridge. In addition, the stiffness coefficient is one of the key factors to affect on dynamic responses of system. Generally, the suitable rigidity of structure is much important to decrease the responses and suppress the vibration of system.
Study Method for Determination Airport Runway Orientation Based on Cross Wind
Authors: Chong Xiao Lei , Cai Wan Tong , Zhang Chao
Published: September 2013

Determination of a runway orientation is a critical task in the planning and design of an airport, and runway orientation is made according result of wind coverage. But there are many shortcomings in current method of wind coverage calculation, such as less precision, process miscellaneous and result simplex, when using the method in determination of a runway orientation. Aim at the situation, through analysis the relation between wind direction and runway orientation, the method is built that becoming all wind to cross wind for runway. Then according annual wind statistic data and requirement of max cross wind, frequency of cross wind exceed limited value for eight runway orientation are calculated in certain airport area. According the result, relation curve between frequencies of cross wind exceed limited value and runway orientation is made. Now, the best and all possible orientation for runway is get under requirement of max cross wind. At last, the method for determination of a runway orientation based on frequency of cross wind is put forward, and the method is a new thought for planning and design of an airport.
Research on the Laws of the Environmental Vibration Induced by Elevated Rail Transit
Authors: Wei Luo , Wang Ping , Le Yan , Hao Liu , Rong Chen
Published: September 2013

Established the Car Line - Bridge coupling dynamic model, then entered the actual parameters of train, track and bridge structural, obtained the dynamic excitation at the rail bridge pier bottom when the train passes. On this basis, established the pier - soil - building coupling dynamic model by combining finite element method and infinite boundary element method, analysed the vibration characteristics of soil and buildings surrounding the elevated rail way, brought an in-depth study to the effects of elevated rail transit train running on the environment. The results show that: 1)The the environmental vibration induced by elevated rail transit is low-frequency vibration, the vertical ground boils down to low-frequency vibration of 10 - 25Hz, the transverse vibration of housing column is fundamental frequency vibration near 10Hz, the vertical floor boils down to low-frequency vibration of 10 - 25Hz. 2) The vertical ground vibration response level decreases with the increase of distance to the rail centerline when the train passes. 3) With the increase of vibration wave propagation distance, components of higher frequency decay more quickly.
The Development of Road Detection Technology
Authors: Xiao Du
Published: September 2013

The road surface plant disease detection is an important content of highway maintenance work, is also a key in the process of highway construction and maintenance management, basic technology. According to index of road surface detection classification discusses the testing method and technology of asphalt pavement, and the road surface detection technology is introduced, meanwhile discusses the trend of the development of detecting technology.
Dynamic Load Coefficient of Tyre Forces from Truck Axles
Authors: Buhari Rosnawati , Rohani Munzilah Md , Abdullah Mohd Ezree
Published: September 2013

This study aims to predict the Dynamic Load Coefficient (DLC) of tyre forces from truck axles. Dynamic Load Coefficient is frequently used to characterise the dynamic loads generated by axles. It is a simple measurement of the dynamic variation magnitude of the axle load, for a specific combination of road roughness and speed. Under normal operating conditions, the DLCs value is typically in the range of 0.05-0.3, and close to zero when the trucks wheels are moving over a perfectly smooth road. To achieve the objectives of this study, which is to determine the DLCs value for seven different types of axles, a simple validated quarter-truck model was excited by a random road surface profile, in order to simulate a vehicle-road interaction. Points are equally spaced along the simulated road to generate dynamic loadings over a broad range of truck speeds. Multiple trucks gross-weight conditions were used to present realistic traffic behaviour. The results showed that irregular road profiles, exciting the vehicle as it travelled, caused continually changing tyre forces. Also, dynamic loading was seen to be fundamentally influenced by the type of suspension (i.e., air and steel), loading condition, and vehicle speed. For example, the DLC value of the tyre forces of the quarter-truck fitted with a steel suspension was found to be more than twice that of the truck fitted with an air suspension. Tyre forces of the one-third laden truck were more aggressive than any other loading condition, due to the uncertain body-bounce generated by the truck, which was strongly dependent on surface irregularities. At low speed, the DLC was greatly decreased if the load was increased. Furthermore, DLC value was always lower for trucks with air suspension over steel suspension, for the same load and vehicle speed. However, air suspension efficiency was clearly better for higher axle loads.
Damage Equivalent of the Flexible Pavement Variation with Load Applied
Authors: Buhari Rosnawati , Puteh Saifullizam
Published: September 2013

Previous research revealed that influence function is strongly influenced the appropriateness of pavement damage prediction and are demanding to be concern in order for better prediction of long term pavement performance. In order to identify the impact of traffic loading condition on the influence function of the pavement toward failure, further stucdy was done to determine the exponential value in the Damage Equivalent Law for varies loading condition and also vehicle speeds. To achieve the aims, the simple quarter truck model was efficiently used with personal computers to predict pavement loading. Towards reality of traffic loading condition will contain a distribution of axles load between unladen and fully laden, the study was further taking into account realistic axle load variation. Results are presented from a study to evaluate the relative influence of truck speed and axle load variation on the stiffness of the asphaltic layer and thus the primary response of the pavement. In conclusion, the exponential value in the Equivalent Damage Law is clearly sensitive to both factor.