bluuebunny/crossref_metadata_2025 huggingface dataset:
Structural Detection and Safety Ensuring Methods of Impervious Wall during Nuclear Power Plant Construction
Authors: Liu Bo , Gong Li , Song Quan Jie
Published: December 2012

Combined with the dynamic compaction example of a nuclear power plant, a fully field tests was conducted to get the permeability and integrality of the impervious wall in real time. The dynamic compaction vibration impact on impervious wall was researched based on the test results. The relationships between damage characteristic and peak particle velocity of impervious wall are suggested also. The safety control standards which used vibration safety threshold to control the potential damage for impervious wall under long-term dynamic compaction were presented. When the PPV of impervious wall is not exceeding the safety threshold, the impervious wall will in its secured state. According to the damage detection method and the presented safety threshold of vibration velocity, the protected structure can be simply and protected during dynamic compaction. The research methods reflects the damage of protected structure directly, and more accurate and safety than traditional methods.
Application and Research of Geologic Radar in Groundwater Disease of Tunnel Engineering Inspection
Authors: Tang Min An , Wang Yu , Sun Bao Ling
Published: December 2012

In order to diagnose the disease degree of operation tunnels and to estimate tunnel's security condition, this paper analyzes the causes of bugs existing behind the tunnel lining, expounds the theory and method of making non-destructive test on tunnel lining quality by using Geological Radar. By processing and analyzing field data, the following functions can be performed, such as detecting the thickness of concrete lining accurately, determining the distribution position and quantities of rebar and grid steel, searching existed cavity and uncompacted area behind the lining especially lining arch top. We also apply the method of morphology to the extraction of liner image feature. We get the liner boundary line and waterlogging area more intuitively by wavelet analysis, and find the anomalous point in the liner. It has been proved that Geologic Radar is a feasible method to inspect the structure of tunnel concrete lining. A dopting hole-drilling method to make verifications with detecting results of geological radar, the results of the two kinds of methods have not big difference.
Analysis for Engineering Example of Dry Jet Mixing Pile Consolidating Foundation
Authors: Wen Shu Lian , Zhang Qing Hong
Published: December 2012

Dry jet mixing pile is the general technique of composite ground consolidation , which is used in foundation treatment of soft soil under highway. It has a widespread applying due to so many advantages. This passage adopts an example of dry jet mixing pile combined with Longkou Shugang expressway engineering, it aims to state that dry jet mixing pile consolidating foundation along intertidal zone would obviously improve bearing capacity, strength and compressive modulus of foundation soil, reduce settlement and make a difference of consolidating foundation in according to data analysis of field or laboratory experiment. This technique is an effective way to solve the Jump Car problem and economic and quick.
Combination of Geological Radar and Video Surveillance in the Tunnel Geological Prediction
Authors: Liu Bo , Li Ning , Lv Gao
Published: December 2012

This paper presents the combination method between geological radar and video surveillance in the tunnel geological prediction, in case the randomness in judgment for the target body prone in the current geological advanced prediction. In order to improve the accuracy, this method conducts geological advanced prediction by comprehensive of geological radar, geological and construction information. In order to verify the effect of this method, we conducted a field trial in the Yululing tunnel. The field trial results are very well. And the accuracy of geological advanced prediction has been improved. This method reached the expected target for the accuracy which we want to improve of geological advanced prediction.
Study on Grouting Effect Evaluation of F4 Weathered Slot in Xiamen Xiang’an Submarine Tunnel
Authors: Huang Xiao Guang , Yang Xiao Lin , Fang Yu Zhong
Published: December 2012

Measurement of water inflow from borehole, drilling and coring, ultrasonic inspection, ground-penetrating radar and field excavation are all used to test effect of grouting water shutoff and reinforcement in F4 weathered slot of Xiamen Xiang’an submarine tunnel. The five test ways are inter-validated to determine the grouting effect accurately and reasonably. It can provide a reliable basis for grouting design, construction and grouting effect test in similar strata. The application and development of grouting in submarine tunnel can be promoted.
The 3D Numerical Simulation and Settlement Control Study for City Tunnel Crossing High Fill Geological Area of Gravelly Soils
Authors: Dong Qian , Wan Hong Yu , Kong Fan Lin , Zhao Bao Yun
Published: December 2012

Three-dimensional finite element model of tunnel-soil-structures interaction was set up to analyze the causes of settlement and structural cracking when tunnel crossing complex gravelly soil area. It simulated the real tunnel excavation process of Chongqing Metro Line 3. Based on analysis and monitoring results, improved technical measures were used to control settlement, such as advance strengthening, excavation speed control and so on. The latest monitoring results indicate that vault and ground settlement are controlled, and convergence value is reduced significantly. The 3D numerical simulation analysis method provides reference for similar projects, and improvement of technical measures is conducive to settlement control.
Analysis of Features and Causation of Rock Burst of Qirehataer Diversion Tunnel
Authors: Chen Shu Wen , Zhao Guo Bin , Chen Xiang Min , Wang Hao
Published: December 2012

Rock burst will happened when the underground engineering is excavated in the hard and brittle rock mass because of high in situ stress or concentrated stress. The length of Qirehataer diversion tunnel is 15.639km,and the maximum over-depth is 1720m. With excavation of tunnel, lightly to moderate rock burst had taken place in 600m length about of tunnel, and moderate rock burst locally. The mainly lithology of tunnel is gneiss granite and the percent is 64.5%, uniaxial compressive strength of which is 63.5MPa so it should be classified hard rock. The maximum principle stress is 30MPa in the place of rock bust. This paper analysis engineering geology conditions of this area and the characters of rock burst, author concludes that posteriority and continuity for time and Traceability and continuity for place are different from others rock burst examples. The reason is that course of stress adjustment is continually and repetitive.
Numerical Investigation of Shield Cross Tunnel Minimum Cover Depth
Authors: Li Guang Ming , Qiao Jin Li , Chen Pei
Published: December 2012

With the development construction of subway in the city, the cross tunnel is becoming common. However, due to the geological conditions of the subway which limited the minimum depth of the shallow overburden of the tunnel is not the same. In this paper, according to the mechanical characteristics of the cross subway tunnel in several typical soil, a three-dimensional finite element mode is established. And to find out the discipline of minimum cover depth in vertical cross the tunnel by researching tunnel shield excavation the ground surface deformation characteristics.
Loess Highway Tunnel Construction Process of Three Dimensional Numerical Simulation
Authors: Liu Bai , Zhang Bin , Kong Jing , Pang Jian
Published: December 2012

In recent years, as China's national sustained and rapid economic development, the state increased investment to middle-western region, promote the regional development of high grade highway. Therefore, highway tunnel through loess area is getting more and more. Due to the special physical properties of loess, it makes the loess tunnel construction a hot topic. To study on the deformation law of the loess highway tunnel, this paper based on the Shanxi Province Guang Ling to Hun Yuan highway tunnel—East Fu Yao tunnel, we simulate the whole section pre-reinforcement construction technique for three dimensional numerical, and combined with field monitoring measurement to compare and analyze in paper
Construction Technology of Cangyuan Tunnel of LanYu Railway
Authors: Qi Su , Zhang Ye , Liu Shu Hao , Liu Nian
Published: December 2012

The phenomenon of railway and road tunnel passing through the debris flow gully is more and more prevalent, for the rapid development of the construction of railways and highways. At present, the construction experience of tunnels passing through the debris flow gully is not rich enough, so the study on this part is necessary. The engineering geological conditions of Cangyuan Tunnel are complex and the construction of which is difficult. The three-step seven-step method, tunnel surface grouting and tunnel root piles reinforcement basis are used to ensure the stability of the tunnel surrounding rock, based on the characteristics of Cangyuan Tunnel which passes through the debris flow gully. The deformation is controlled within the specification range, which indicates that the construction effect of Cangyuan Tunnel is good. These construction measures solve the construction problems of tunnels which pass through the debris flow gully and ensure project quality and duration, therefore, these construction measures can be used in similar projects.
Stability Analysis of Rock and Effect Evaluation of Supporting Scheme in Tianchi Underground Plant
Authors: Luo Tao , Qiu Huan Feng , Fu Shao Jun
Published: December 2012

With the implementation of Western Development, West-to-East Electricity Transmission Project and South-to-North Water Diversion Project, a large number of hydro-power stations have been built in the west middleland regions of China. Because of the complexity of terrain, geological and physical-mechanical conditions, the stability of large underground structures becomes one of the most important problems during the engineering design, construction and operation. This paper will take Tianchi hydro-power station as an example, according to the measured stresses at several points, the in-situ stress field is feedback analyzed by using the combination of the genetic algorithm and 3D finite element method. Then, the rheological model of bolted joint rock and nonlinear finite element method are adopted to calculate the displacement field, stress field and D-P point safety factor of the underground structure. The stability of the underground structure is discussed, the excavating and supporting scheme are also presented, and the supporting effect is evaluated. The achievements in this paper can not only be taken as the reference to the design, but also provide some design experiences for other underground structures.
Determination Minimum Value of Face Support Pressure for Underwater Tunneling with Complex Condition
Authors: Liu Xue Yan , Yuan Da Jun
Published: December 2012

Underground water is a big problem for tunneling under rivers or oceans. So it’s practical method to consider pore pressure for determination minimum value of surface support pressure. What’s more, the earth thickness above excavation tunnel changes because of the riverbed existence, which makes surface support pressure more difficult to set. Active earth pressure theory, Murayama formula and fluid-structure interaction theory are used to analysis the minimum value of surface support pressure. Relationship between support pressure and horizontal displacement, which is supporting characteristic curve, is established. The determination principle for minimum value of surface support pressure is comprehensive analysis of plastic zone development and the level of face horizontal displacement. The results suggest that: the active earth pressure can be used as the lower limit for surface support pressure set in horizontal excavation section; but it can’t meet the requirements for the uphill section of notching section. But minimum value of surface support pressure for the slurry can be determined by supporting characteristic curve.
Numerical Simulation of Vortex-Induced Vibration of Submerged Floating Tunnel Cable
Authors: Luo Gang , Zhou Xiao Jun , Wang Shuang
Published: December 2012

A two-dimensional RSM turbulence model combined with enhanced wall function method is used to solve Naviar-Stokes equations，and Fourth Order of Runge-Kutta method is embedded in FLUENT’ UDF for Solving vortex-induced vibration equation of the cable of the submerged floating tunnel .The weakly coupled fluid-structure interaction algorithm is applied to solve the vibration equation and Naviar-Stokes equations, respectively,and the structure systems and fluid systems are combined with the lift coefficient, drag coefficient and dynamic mesh technology. The following conclusions: submerged floating tunnel cable presents non-locking and locking the two phenomena with the increase of the reduced velocity; In the non-locking region, the cable vibration beat phenomenon; in the locked region, vortex frequency is closed to the natural frequency of the cable and vortex-induced resonance leads to a significant increase of the cable displacement and the lift and drag.
Numerical Analysis of Underground Engineering on Self-Developed Finite Element Method
Authors: Yu De Hai , Jiang An Nan , Wang Jun Xiang
Published: December 2012

The self-developed finite element method has many advantages and good prospects to solve problems of underground engineering. The program is used to the simulation of the true tunnel, while it is embedded into self-developed algorithm. The results indicate that self-developed finite element method has many advantages and good prospects to solve geotechnical problems, and it can be used for quantitative analysis of underground engineering.
Application of Slope Safety Automatic Monitoring Technology in the Project of Road No.1 in Republic of Congo
Authors: Yang Pan , Zhang Shu Dong , Guo Jun Mei , Ma Cheng Xuan , Shen You Cheng , Yang Jun
Published: December 2012

Slope safety has been well concerned by the society in recent years. Slope displacement monitoring is an important subject of slope safety and its research has been developing rapidly. In this article, we draw up a pilot slope safety automatic monitoring scheme for the project of Road No.1 in Republic of Congo, which depends on real-time displacement monitoring. This scheme uses fixed inclinometer as its main appliance and achieves wireless data transmission. During this process, we considered both local climate and the characteristics of high slopes along the road, and finished a series of work including monitoring position selection, critical slip surface prediction and finally monitoring system establishment. Our ultimate objective is to achieve real-time monitoring of slope situation, and furthermore set up the relationship among slope displacement, rainfall and time. With the derived relationship we would be able to forecast the development of slope deformation and possible danger caused by the slopes.
Numerical Simulation Research on Deep Soft Rock Roadway
Authors: Zhang Bin , Yu Xiang Lian , Liu Ning , Zhu Feng
Published: December 2012

The soft rock roadway support is one of difficult problems in the mineral engineering. For making the stress and strains of support system to be effective forecasted in the process of roadway support. The Adina finite element software is used to do numerical simulation about the strains of the supports system in the process of the Hama mountain roadway, and compare with the date which was got from the field monitoring. The date comparison shows that the results of simulation is basic anastomotic with the examination at present. So that it can be well predicted the effectiveness of the support measure when using the finite element simulation software –Adina.
Numerical Analysis of Influencing Factors of Stability in Thick Coal Seam Mining Roadway
Authors: Li Zhi Hua , Hua Xin Zhu , Yang Ke , Zhu Ruo Jun , Zhou De Sheng
Published: December 2012

The FLAC-3D software was used to study the surrounding rock displacement and the side abutment pressure distribution laws about roadway in thick coal seam. Based on this model, through change the mining height, working face length and mining depth, the differences of roadway underground pressure characteristics were analyzed between thick coal seam working face and normal working face. The results indicate that: ①the displacement of roadway surrounding rock increases with the increase of mining depth and mining height, the closer to the coal wall the larger of the increase range of roadway displacement. ②the peak of side abutment pressure increases with the increase of mining depth and mining height, the peak district of the stress will move toward the inner department of rock body. ③ the effect of working face length on the roadway displacement and the side abutment pressure is very feeble.
Study on Seismic Failure Mode of a Rigid Frame Bridge with Super High-Rise Piers
Authors: Fan Zhen Hua , Zhang Xie Dong , Zhang Hang
Published: December 2012

Recently rigid-frame bridges have been built for only twenty years in China and they have been used as the preferred bridge type in complicated terrain mountainous areas. Based on the fiber model in Opensees, the typical nonlinear numerical analysis model of a rigid frame bridge with super high-rise piers is presented. IDA method is adopted for the nonlinear dynamic history analysis for the structure. The failure mode and the characteristic of plastic development are investigated under longitudinal seismic actions. The results show that multiple key sections of the piers enter the plastic state simultaneously and the structure will become dynamic instable inevitably.
Spatial Mechanical Behavior Research of Cable-Pylon Anchorage Zone of Steel Box Concrete Tower
Authors: Dang Dong , He Shuan Hai
Published: December 2012

In order to grasp the force performance and stress distribution of shaped pylon steel anchor box under the action of the cable tension, with a main span of 555m length of three towers cable-stayed and self-anchored suspension combined system bridge as the engineering background, through the ANSYS APDL command stream parametric programming, the different finite element models of pylon steel anchor box is established by the spatial solid element and shell element, the mechanical properties of cable-pylon anchorage zone were studied under the most unfavorable load combination, considering the stress state and distribution characteristics of steel anchor box under different orthodontic force. The results showed that, under the most unfavorable combination of loads, the stress was concentrated at the position of the anchor plate and pressure plate using the initial strain mode; the calculation results of solid element and shell element were consistent by uniform loading mode, which could reflect the real stress state of steel anchor box, but the shell element corner contact area prone to stress calculation distortion. The results provide the basis for the design and have some design reference value for the design of the same type bridge.
Influence of Cable Dampers on Cable-Stayed Bridges
Authors: Liang Dong , Shen Hui Cai , Li Yan Feng
Published: December 2012

Cable-stayed bridges have seen a wider application in recent years, with many having longer and longer spans. Modern cable-stayed bridges are using numerous cables to support the stiffing girders. Many cable dampers are installed to mitigate cable vibration. This paper focuses the attention on the effect of cable damper on the dynamic characteristics of the whole cable-stayed bridge, especially the modal damping. A practical model comprised of the cable, girder, and damper is developed to analyze the relationship between system modal damping and the performance of cable damper with complex mode method. A test model with cable, girder and damper was made to verify the theoretical results. A finite element model of a simplified cable-stayed bridge based on test model is adopted to assess the effects of cable dampers on the anti-seismic performance and wind-resistant behavior of the cable-stayed bridge. The results show that the cable dampers of cable-stayed bridge can increase the modal damping of the whole bridge.
Estimation of Scale of Fluctuation of Soil Properties Indexes
Authors: Yan Shu Wang , Guo Lin Ping
Published: December 2012

By summarizing and comparison of methods for evaluating the scale of fluctuation, suitable and convenient method to calculate correlation distance is obtained. The space averaged method is employed to analyze the scale of fluctuation of soil in the vertical direction of Tianjin combining geology data, and regional representative values are obtained, which is of high application value on risk assessment and reliability analysis in geotechnical engineering.
Introduction of Shaking Table Test of Rigid Frame Bridge Model
Authors: Yan Xiao Yu
Published: December 2012

To investigate the seismic response of long-span rigid frame bridges with high-pier, the shaking table test of a 1/10 scaled rigid frame bridge model is introduced in this paper. Details about test equipment, model design, test arrangement, input ground motion waves and test principle are provided. The response of bridge model under the seismic excitation included the uniform excitation and the multi-support excitation is observed. The influence of the soil-structure interaction on the bridge is considered through the real-time dynamic hybrid testing method. The impact effect for different ground motion input during the test is discussed. The influence of multi-support excitation, soil-structure interaction and impact effect on structural seismic responses are studied based on the test results. The isolation effectiveness and the damping effect are discussed as well.
Seismic Analysis of Reinforced Concrete Rib Arch Bridge
Authors: Hu Da Lin , Qu Tian Qi , Wang Hong Bin , Chen Long Gang
Published: December 2012

There are few researches on seismic response of reinforced concrete rib arch bridges at present; therefore, it is necessary to analyze seismic performance of this kind of bridges. Based on the engineering background of a three-span reinforced concrete rib arch bridge, a full bridge finite element model is built to analyze the structural dynamic characteristic and seismic response of the bridge. The internal forces and displacements of each key section is compared and discussed when the bridge is excited by horizontal unidirectional ground motion or the combination of vertical and horizontal ground motion. The structural seismic response calculated with different analysis methods is compared. The research results of this study can be used as a reference for the seismic design of similar bridges.
Application of Weibull Distribution in Calculating Ground Deformation
Authors: Li Shi Bo , Lu Hong Jian
Published: December 2012

Weibull distribution was applied to calculate the ground subsidence and deflection value, in order to analysis accurately the influence of ground subsidence caused by underground mining on high voltage electric power lines. The results showed that the effect of reducing surface subsidence was notable and the high power line was working normally. It was accurate enough to calculate ground deformation by using Weibull distribution, and Matlab program can be used to solve the function feasibly.
Research on Water-Stop System of HZM Bridge Precast Pile Cap Installation
Authors: Liu Jian Bo , Wu Qi He , Tian Wei
Published: December 2012

Hong Kong-Zhuhai-Macao Bridge (HZM Bridge) is located in the LingDing Sea area outside the Pearl River estuary, where the hydrological and meteorological are very complex. Because the effective operating time was short and environmental protection requirements were high, the bridge construction is very difficult. For this feature, the method of non-navigable pier construction was used factory prefabrication and on-site installation. Unlike the traditional way of the bridge pier construction, this method can greatly shorten the time to operations at sea, by which all piers will be prefabricated in the factory and these will be only installed at the on-site. The construction of water stop between precast cap and steel pipe pile is the key aspects, and also one of the main focuses. This article introduces the water-stop system selection, design and test etc. three aspects.
X-Bridge Project: Development of a New Methodology for the Monitoring of Steel Bridges
Authors: Marconi G.Paolo , Remondino Fabio , Jiménez Fenández-Palacios Belén , Cozzini Marco
Published: December 2012

The main aim of this paper is to describe the results obtained applying a new methodology developed in order to assess the presence of overloaded areas in steel bridges. The methodology is based on the principle that if the load applied (also just once) in a particular area is higher than the yield strength, it changes the residual stress in this area, inducing a different value of stress if compared with the other areas not overloaded. Using X-Ray diffraction it is possible to detect the value of residual stress on the surface of metals, also in small areas, in a non-destructive way. Therefore this technology is used to detect the presence of overloaded areas on steel bridges. As the areas sampled from X-Ray diffraction are very small (1-2 millimeters of diameter) compared with the dimensions of a bridge, it is necessary to know exactly the position of the areas subjected to the maximum load during the life of the bridge. For this reason FEM analysis are previously conducted in order to evaluate maximum load regions. The construction drawings necessary to perform the FEM analysis are not always available, especially for old bridges, therefore reality-based 3D models are created this problem. Such method is also useful by itself, as beside providing suitable drawings for the FEM analysis, it allows to quickly identify possible large deformations of the bridge structure.
Geometry Control Technology of Transition Curve Section in Cross-Sea Bridge Erected by Precasting Segment Girder
Authors: Huang Yue , Zheng He Hui , Wang Min , Wu Xing Fa
Published: December 2012

The short line match-cast method of precast segments has proved to be the most versatile and reliable way to concrete bridge construction. The success of match-cast method relies heavily on accurate geometry control in precasting as the scale of adjustments during erection is very small and difficult to implement. So the required levels of accuracy in segments match-casting are stringent in order to assure erection accuracy. Therefore, the research on segments match-casting and geometry control technique of space distorted segments are very important.Based on the principle of match-casting using the short-line method, the geometry control technology of transition curve section in cross-sea bridge erected by precasting segment girder is proposed. As an example of south approach spans in north branch of Xia-zhang Cross-sea Bridge, this paper will provide a reference for the construction of similar bridges.
Development of Methodology for Enhancing Visual Bridge Condition Assessment Using Image Processing Techniques
Authors: Wi Hui Ju , Lee Jae Ho , Blumenstein Michael , Guan Hong , Loo Yew Chaye
Published: December 2012

Many bridge authorities have implemented Bridge Information Systems (BISs) or Bridge Management Systems (BMSs) to effectively manage their routine inspection information. The success of a BMS is highly dependent on the quality of bridge inspection outcomes and accurate estimation of future bridge condition ratings. To ensure such successful outcomes, a BMS must (1) contain reliable, consistent and accurate condition data from routine bridge inspections; and (2) encompass reliable deterioration modelling that overcomes the shortcomings of a lack of historical bridge inspection records. However published literature demonstrates that several limitations exist particularly in terms of inconsistency of inspection outcomes due to subjective judgment. To minimise such limitations, this paper presents a feasibility study for the enhancement of the current visual bridge inspection method using optical image processing techniques. The development work consists of image processing and knowledge-based approaches. It is anticipated that the proposed method is capable of minimising the shortcomings of subjective judgment on condition rating assessment and providing cost effective solutions to bridge agencies. Ultimately, the proposed bridge inspection methodology can provide consistent and accurate evaluation on the condition states of bridge elements. This in turn will lead to more reliable predictions of long-term bridge performance.
Research on Pile-Sinking System of Steel Pipe Pile in Full Size Model Process Test of HZM Bridge
Authors: Zhang Hong , Tian Wei , Guo Qiang
Published: December 2012

The process of the pre-fabricated abutment and pier foundation construction by bed-burying method is adopted in The non-navigable arch bridge of HZM Bridge, According to the technology difficulties of sinking the pile accurately, A kind of tool type guide pile system with guideing and limitation function is put forward and designed, of which the structure and working method were introduced in this paper.
Structural Type Selection for Long-Span Bridges in Mountain Area
Authors: Liang Dong , Yao Chang Rong , Liu Sai Zhi
Published: December 2012

As the western region is a mountainous area with geology complicated geological conditions, the proportion of bridges and tunnels is bigger. Based on the characteristic of mountainous route and long-span bridges, this paper discussed the conceptual design of mountainous bridges. Firstly, this paper analyzes the characteristic of mountainous long-span bridges and proposed some fundamental principles to design long-span bridges. After the comparison of the main bridge structures, the paper points out that the designer should select the best programs considering hydrological, geological, geomorphology, construction technology, transportation , geographical environment and social environment. The purpose of this paper is to give reference for the conceptual design of mountainous long-span bridges.
Study of the Effect on Efficiency of External Prestressing and Economy to Box-Girder Bridge with Different Styles of Webs
Authors: Zhu Jin Song , Li Jian Feng
Published: December 2012

Prestressed box-girder bridges have been applied in modern bridges widely as the perfect structural performance, the design method and calculation theory of prestressed box-girder bridges have been relatively perfect. The self-weight of box-girder bridges is reduced during the process of development from concrete structure to composite structure. The prestressed efficiency and the economy are also improved, simultaneously. But up to now, the quantitative research of the effect on efficiency of external prestressing to box-girder bridge with different styles of webs is lack. This paper illustrates the effect on efficiency of external prestressing and economy to box-girder bridge with different styles of webs. The results show that the box-girder bridge with corrugated steel webs has the highest prestressed efficiency and the lowest life cycle cost and the best economy.
Research on Modal Parameter Identification of the Cable Stayed Bridges Based on the Singular Value Decomposition of the Power Spectrum
Authors: Xiong Hong Xia , Qin Ci Feng , Jiang Yang
Published: December 2012

In view of the modal parameter identification when only has the output signals of the system under ambient excitations has difficulty, a new method which can identify the structural modal parameters exactly based on singular value decomposition of the power spectrum is put forward. This method is used in the modal parameter identification of a cable stayed bridge under ambient excitations, and the identification frequency is compared with the finite element computation frequency. The results indicated that this method has overcome the subjectivity in modal selection of frequency domain pick-peaking method, choose eigenfrequency and identify close modal accurately and objectively. With the advantages of practical, processing simply and fast.
Effect of Axial Magnetic Field Strengths on Radial Velocity Field in Liquid Bridge under Microgravity
Authors: Liang Ru Quan , Yang Shuo , Ji Jun Hong , He Ji Cheng
Published: December 2012

This article studies on the effect of magnetic field strengths on the flow field in a liquid bridge under zero gravity. The mass conservation level set method is used to track the two-phase interface. The results show that inhibitory effect of additional axial magnetic field on thermocapillary convection within liquid bridge is obvious, and this kind of inhibitory effect increasing as the magnetic field strength is strengthened.
The Effect of Static Wind Loading on Flutter Stability of Self-Anchored Suspension Bridges
Authors: Li Tian Fei , Kou Chang Huan , Kao Chin Sheng , Jang Je , Wang Yi Min
Published: December 2012

Due to the benefits of having a larger span length, a more elegant structural shape, better adaptability and financial feasibility, the use of self-anchored suspension bridges as solutions in the engineering industry has been widely adopted. Based on the theory of 3D flutter analysis, this study chose to analyze an entire bridge. The effect of initial wind attack angle and static wind loading on the flutter stability of self-anchored suspension bridge was investigated. The results show that the critical flutter wind speed varied noticeably with different initial wind attack angles, and that an angle of +3° gave the most adverse state. Moreover, when static wind loading was considered, while changes in structural vibration characteristics showed little influence on the flutter stability of self-anchored suspension bridge, the added attack angle on the main girder affected the flutter stability remarkably.
Research on Wind-Induced Vibration Reduction Solution of the Longest Cantilever State of Jiashao Bridge
Authors: Zhang Hong , You Xin Peng , Peng Cheng Ming
Published: December 2012

A research based on Jiashao Bridge is carried out to reduce buffeting response under strong wind of the control section of main girder of the longest cantilever state and to ensure the security of the bridge during the construction period. A method that the ends of cantilevers are connected with several temporary damping cables is considered as wind-resistant measure. 4 modes with different damping cable arrangement are supposed, and the wind-resistant effect corresponding to the 4 modes are compared by FEM analysis. A mode with the best wind-resistant effect and economical meanwhile is selected out and local optimization is added to the selected mode. Some valuable conclusion obtained from the research could be adopted in Jiashao Bridge and the similar projects.
Research on Surface-Layer Improvement Technology for Dredger Fill by Vacuum Preloading
Authors: Yang Yan Hua , Ji Fu Quan , Yang Zhao
Published: December 2012

The surface-layers have very high water content and low bearing capacity, so far to be the very soft clay foundation, which come from the reclaimed land in project of reclamation. It is difficult to improve the very soft clay foundation by traditional vacuum preloading. A new method named surface soft soil improvement is presented in this paper, which can make the soft clay foundation to be improved in preliminary. Once forming the hard coat layer, the foundation may reach the needs of further construction. In the construction technology, the horizontal filter pipe net is used to instead of the sand bedding course. By laying of woven cloth and non-woven geotextile over the surface of reclaimed silt, installing PVDs by manpower becomes possible. Besides, the vertical PVDs all are connected with the horizontal filter pipe net directly, that makes a whole spatial drainage system. The loss of the degree of vacuum is decreased, and the improvement is increased. Thus, this construction technology is as a reference to the large scale engineering construction and similar projects.
Study on Fiber Modified Slurry Technology
Authors: Zhang Xiang Dong , Zhang Bo , Sun Chuang
Published: December 2012

In recent years, as the rapid development of highway construction and the increase of road traffic mileage of China, the highway traffic safety smooth has become an essential question of highway projects. In this paper, the second line which was modified by fiber slurry of S211 provincial highway construction engineering as the test prototype. We have calculated the optimum mixture ratio of the slurry mixture which was modified by fiber in the laboratory. In this condition, the shear performance, anti-fatigue performance, water damage resistance and mechanical impact resistance performance of the mixture have improved compared with the mixture without fiber modified. At the same time, the same section road with fiber modified slurry mixture and without fiber modified slurry mixture have been compared and analyzed by finite element method based on the ANSYS. We could draw some basic conclusions: The value of pavement deflection and the tensile stress of fiber modified slurry layered road have reduced compared with the slurry layered road without fiber modified.
Key Technique on the Process Control for Construction of Hohhot Circle Expressway Asphalt Pavements
Authors: Zhao Bin , Hao Pei Wen
Published: December 2012

As vehicle flow on arterial highway in Inner Mongolia sharply increased, the originally designed natural increase rate of 8% per year has been exceeded on the vehicle flow in some sections. According to statistics, monthly average vehicle flow on major section of G6 expressway has reached a standard flow of 67478 vehicles per day and night, of which in 70-80% are large ones for coal transportation. Therefore, pavement load and road capacity have exceed the designed expressway load capacity. At present, semi-rigid base asphalt pavement structure is still widely used for high-grade highway pavement in Inner Mongolia. With years of construction for such pavement structure, a great deal of valuable experience has been gained on construction technology. However, there are still a few deficiencies in the quality of raw materials, gradation control of asphalt mixture and adjustment of equipment, etc. Hohhot circle expressway connects with the G6 and G7 expressways, suffering from problems such as large vehicle flow and load overweight. This paper introduced a key technique that should be properly controlled during construction of such pavement structure, emphasized technique control and management of the following aspects, i.e. ballast sizes and gradation control, asphalt concrete mixture, adjustment of pavers, validation of mixing proportion in production and reasonable arrangement of process, and summarized corresponding technical measures taken during construction of asphalt pavement in this project.
The Application of Dynamic Compaction in Road Bed Handling
Authors: Ma Li Jie , Sun Ji Shu , Zhang Jin Yu
Published: December 2012

This paper described the working principle of dynamic compaction and the main points of construction, Using degree of compaction and deflection, evaluating construction quality based on actual project. we can solve the problem of construction quality of the road bed effectively and the waste of the dust, thus avoiding the environment pollution of waste dust and make a good economic and social profit.
Study on the Variability of the Surface Flexural Strength of Hardened Concrete in Laboratory
Authors: Yue Ai Jun , Liang Jun Lin , Zheng Jian Long
Published: December 2012

he experimentation was to study the effect to cement concrete surface flexural strength by simulating the different natures and thickness of cement mortar, The slump was defined as 20mm and 70mm, on behalf of the low plasticity of concrete and plastic concrete, the three conditions of the surface mortar thickness 25mm, 15mm and 5mm was to simulate the different thickness of mortar extracted during concrete construction,which adopted three different mortar ratio and mortar consistency, the concrete specimens with the 150*150*550mm steel mould were made from concrete and the surface layer of mortar,the specimen surface as a curved flat was to determine the surface flexural tensile strength.The results show that: the surface flexural strength of concrete is affected by the components,natures and thickness of cement mortar, the higher the surface mortar strength is, the higher concrete surface bending strength is.
Mechanics Analysis of the Structure of Fly-Ash-Flushed-by-Seawater Base Asphalt Pavement under Heavy Load
Authors: Yu Ling , Yang Jing , Bao Long Sheng , Zhu Guang Shan
Published: December 2012

In order to find out the loading mechanism of Fly-Ash-Flushed-by-Seawater base asphalt pavement under heavy load and verify reasonable road pavement structure, this paper analysed the road model under different axel load with ABAQUS. The influence of structural stress and the road asphalt pavement deflection in different road structural parameters were shown in the paper. The result indicates that the structural stress and the deflection under heavy load are greater than they are under the standard load. When the vehicle is over load by 100％, the tensile stress of subbase is close to the allowable tensile stress. The structure of Fly-Ash-Flushed-by-Seawater base asphalt pavement can be designed to adapt to the over load traffic of Yingkou by adjusted the structural parameter in a certain range.
Calculation of Land Subsidence Induced by Dewatering of Pit Based on Comprehensive Template Model
Authors: Zhang Duan Mei , Li Qin Wei , Wei Run Chu
Published: December 2012

Based on the hierarchical summation method of elasticity theory, the comprehensive template model of land subsidence induced by dewatering of pit is put forward. According to the soils experience range of conversion relationship β (between deformation modulus E0 and compression modulus Es ), we can calculate upper and lower limits of Es. When the compression modulus Es is respectively taken upper and lower limit, the curve between falling groundwater values and sedimentation values can be taken in conditions of unit thickness different soils of different pore ratio. So the comprehensive template model is built. The example shows that the comprehensive template model can be effectively calculated land subsidence induced by dewatering of pit.
Pavement Primary Response Using Influence Function and Peak Influence Function
Authors: Buhari Rosnawati , Collop Ac.
Published: December 2012

It was identified in previous research that errors in theoretical damage much associated with the influence function calculation. Thus, this paper present the efficient prediction of primary response due to dynamic vehicle loading using influence function and peak influence function approach. In order to provide the realistic loading condition, dynamic road response model with idealised loads representative by mathematical quarter-truck model with two degree of freedom was excited by a random road surface profile which equally spaced points along the simulated road with various different speeds. Consequently, the simplified computational approach (peak influence function method) was identified only a few points gave a small different compare with the influence function method for along the longitudinal distance. In order to identify the impact of both methods, further implementation was done to calculate fatigue damage (horizontal tensile strain at the bottom of a bound layer) or rutting damage (vertical compressive strain at the top of the subgrade layer) predicted by constant load moving at varies speed. It was found that the differences in response are particularly small and increased steadily as the increasing of the vehicle speed. It was conclude that the simplify calculation was able to predict stresses and strains sufficiently accurately and identified relatively small errors into the pavement damage prediction. Hence the simplification in particular much reduced the computation time sufficiently and minimized the computer resources significantly.
Application of Composite Waterproofing and Drainage Board in Low Embankment Highway
Authors: Ruan Yan Bin , Wu Wan Ping , Wang Yun
Published: December 2012

This paper introduces the composite waterproofing and drainage board, to solve issues such as the drainage problem and lack of sand gravel material in low filled embankment of plain area highway. Through the research of its application performance, design method and drainage effect. Studies show that the materials with perfect performance on tensile and compression strength are contribute to construction property of soil which under the board, it also can effective prevent water from seeping through the underground, and expel surplus water, to make sure the long-term stability of subgrade and subsoil. It is one perfect waterproofing and drainage materials used in low embankment highway.
Nonlinear Finite Element Analysis of Flexible Berthing Pier Based on P-Y Curves
Authors: Su Jing Bo , Zhu Yi Huan , Wu Feng
Published: December 2012

Flexible Berthing Pier is a port structure that absorbs, partly or totally depending on self- deformation, the ship berthing energy and the ship rolling energy caused by the wave. Flexible berthing pier mainly sustains the horizontal load. Present methods to calculate the horizontal bearing capacity of pile foundation consist of P-Y curve method, NL method and m method. P-y curves method is one kind of nonlinear subgrade-reaction methods; it considers the nonlinear character, layer character, different kinds, and load kinds of ground soil. Starting from the concept of spring joint in Newmark method, the contact non-linear finite element model is founded for the pile-soil system. By the formula of P-Y curves of compound foundation reaction method, the formulas of elastic coefficients of non-linear springs are deduced. The corresponding programs are organized based on Marc. By the numerical example, the rationality and the feasibility of the presented method is validated.
Wave-in-Deck Impulsive Pressure on Unsheltered Jetties Exposed to Waves and Current
Authors: Meng Yan Qiu , Chen Guo Ping , Yan Shi Chang
Published: December 2012

Impulsive pressure induced by waves is an important factor to be considered in the design of offshore structures. This paper presents results from physical model tests on the impulsive pressure on deck of unsheltered jetties and similar structures exposed to directional waves in the presence of currents. The pressures were measured on a 1:50 scale model of a jetty head with down-standing beams and berthing members. Different incident wave angles, the current velocities and the angles between wave and current were considered to identify the effects of these factors on the impulsive pressures. Data collected from model tests were analyzed to gain insights on the mechanics of the impulsive pressure under different wave and current conditions. It is shown that the impulsive pressure is sensitive to the wave directionality and the current magnitude.
The Application of FPSO in Oil and Gas Exploitation
Authors: Guo Ting , Qin Hong De
Published: December 2012

The far-flung ocean has abundant resource and the exploitation area of ocean oil and gas is developing from offshore to deepwater and ultra-deepwater following the increase demand for oil and gas resource. Therefore, one of the floating structures for deepwater exploitation is FPSO. The yaw of FPSO is more important problem to solve. This paper use Hydrostar to compute the RAOs, 1st-order and 2nd-order force of FPSO. A comprehensive review is introduced about the research on FPSO hydrodynamic in the world, including the coupling hydrodynamic analysis of deepwater FPSO with the mooring system. The results indicate that the FPSO’s 1st-order force and moment is a little large, however, the RAOs and 2nd-order force and moment are good. The FPSO with single point mooring system can control the displacement of FPSO effectively.