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The Dalian Bay Subsea Tunnel is constructed using the immersed tube method, where 18 sections of immersed tubes are prefabricated using a fixed dry-dock. The dock entrance serves as a protective barrier between the dry-dock and the sea, playing a crucial role in ensuring dock safety by preventing water ingress and providing wave protection. On the premise of safety and economy, it is necessary to take into account the convenience of construction and the ease of use. On the basis of summarizing the typical dock gate types for prefabrication of immersed tubes both domestically and internationally, this project adopts the fixed dry dock method, gravity-type dock entrances, and large floating caisson gate system. The dock entrance system incorporates curtain grouting, water stop strips, steel gates, and concrete structure water stop system, and is equipped with the energy dissipation self-flowing water dock gate pier structure. The caisson of floating dock gate adopts cast-in-situ scheme, which can provide reference for similar projects. [ABSTRACT FROM AUTHOR]

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Copyright of Transportation Science & Technolgy is the property of Transportation Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The suspended monorail is a new mode of rail transit with light weight, medium speed and low cost. It has a lightweight and aesthetically pleasing structure but has obvious limitations when spanning obstacles such as rivers and valleys. From the perspective of structural force and operational safety, this paper puts forward a new composite beam structure scheme, in which track piers and track beams are erected on the main beam of a cable-stayed bridge, overcoming the limitations of conventional suspended monorail spanning ability. To investigate the complex force situation and the load transfer path at the junction of the main beam of the cable-stayed bridge and the track beam piers, finite element models of steel box girder section and concrete box girder section were established using ANSYS software. The results showed that, in the steel box girder section, the pier load was mainly transferred to the diaphragm and the middle web directly connected to it. Among them, the diaphragm load experienced relatively uniform stress, while the middle web's stress was mainly concentrated within a 2-meter radius centered around the pier, which could be mostly transferred to the steel girder bottom plate. 58% of the pier's axial force was transferred to the directly connected diaphragm. During the transfer of the pier column's transverse bending moment, 58. 8% of the shear force was transferred to the directly connected diaphragm. During the transfer of the pier column's longitudinal bending moment, 53. 4% of the shear force was transferred to the middle web. In the concrete box girder section, the pier load was mainly transferred to the concrete web and diaphragm directly connected to it. The concrete stress was mainly concentrated within a 2-meter radius centered around the joint surface, and the pier load was basically transferred within about 0. 5 meters below the joint surface. 68. 8% of the pier's axial force was transferred to the directly connected diaphragm. During the transfer of the pier column's transverse bending moment, 86. 4% of shear force was transferred to the directly connected diaphragm. During the transfer of pier column's longitudinal bending moment, 44. 6% of shear force was transferred to the middle web. [ABSTRACT FROM AUTHOR]

Copyright of Railway Construction Technology is the property of Railway Construction Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Construction Technology is the property of Railway Construction Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to promote the industrialization development of reinforcement in pier towers, three kinds of structural optimization design of reinforcement parts were proposed. Taking the connection mode of main reinforcement and stirrup, stirrup structure and stiffness skeleton as parameters, the four-point bending test of two reinforced concrete beams was carried out (the new reinforced concrete beam was referred to as the new beam, and the traditional tied reinforced concrete beam was referred to as the traditional beam), and the bending mechanical properties of the optimized design structure of the new pier tower reinforcement parts were studied. The test results show that the crack distribution of the traditional beam is denser than that of the new beam, the peak load of the traditional beam is about 5% higher than that of the new beam, and the ductility of the traditional beam is slightly higher than that of the new beam. The reinforcement strain of the two specimens is basically consistent with the variation load. Under the same load, the stirrup strain of the new beam is about 50% (500 με) larger than that of the traditional beam, and the stirrup restraint capacity and load sharing ratio of the new beam are higher. In general, the bending resistance mechanical properties of the new beam are basically the same as those of the traditional beam. The welded connection of the main stirrups of the pier tower and the new stirrup structure can be used in practical engineering. [ABSTRACT FROM AUTHOR]

With the construction of high-speed railway entering a new period, the frequency of railway viaduct stations has increased dramatically. When the pier is high, the space under the viaduct station has a large demand for utilization. Due to the rigidity control, the conventional pier layout is relatively dense, it is likely to form the phenomenon of "pier forest", which is not conducive to space utilization and has poor aesthetics. In order to find a reasonable structural system suitable for high pier viaduct station, this paper takes Dingyuan viaduct station of Hefei-Xinyi High-speed Railway as the engineering background, the existing problems of common structural systems are studied in the design, and a bridge structural system of sparse-piers and semi-integral viaduct station is proposed. This structural system adopts prestressed beam portal pier with cantilever with two inclined columns, which greatly reduces the number and volume of piers, and maintains good mechanical properties. A kind of fixed support which can release horizontal force is innovatively proposed, which improves the overall stiffness of the structure by changing the structural restraint system. Compared with common structural systems, it can greatly improve the utilization efficiency of the space under the bridge, greatly reduce the structure size and top displacement of piers, and has good aesthetics, practicality and structural mechanical performance. It provides a new idea for the bridge structure design of high-speed railway and other rail bridge viaduct stations. [ABSTRACT FROM AUTHOR]

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To overcome the deficiency of large numbers of nonlinear time history analysis for seismic fragility assessment of complex bridge structures, a fragility analysis method based on endurance time method (ETM) is proposed for rapid assessment of bridge fragility. Firstly, several endurance time accelerations (ETA) are synthesized according to ETM and combined with probabilistic seismic demand model. Subsequently, a sample library of finite element model for a long-span steel-truss deck arch bridge is established by using OpenSEES software with the consideration of bridge model uncertainties. ETM and incremental dynamic analysis (IDA) methods are employed to carry out nonlinear time history of the bridge models to obtain the fragility curves of typical components, and the applicability of ETM is validated by comparing the results of the two methods above. Results show that the relative error between ETM and IDA is basically controlled within 5%, indicating that the fragility method based on ETM can effectively take into account both analysis efficiency and calculation accuracy; Under the action of longitudinal earthquake, the seismic indexes (i. e., 0.597g and 0.972g) of approach pier and junction pier of steel-truss deck arch bridge with 50% moderate damage probability are much smaller than that of other components, illustrating that concrete piers are the most vulnerable members. The failure probability of arch ribs and columns under earthquake is small while the vault and arch foot are relatively weak. Short columns with fixed supports are susceptive to be damaged subjected to the longitudinal earthquakes, which can be optimized by changing the support layout of columns. [ABSTRACT FROM AUTHOR]

Partial cable-stayed bridges have the advantages of high rigidity, good economy and convenient construction. In recent years, they have been widely used in high-speed railway, but most of them are two-tower structures. In this paper, based on the main bridge of Ji'nan Yellow River Bridge on Zhengzhou-Ji'nan Railway, the structural system, side-to-middle span ratio and key parameters of beam-tower-cable are analyzed and studied for the long-span, five-tower, four-span and large-span partial cable-stayed bridge on high-speed railway. Through comprehensive comparison and study, the structure system of tower pier consolidation is selected for the Yellow River Bridge, which has the advantages of partial release of temperature force, bridge stiffness and track surface irregularity index to meet the requirements of ballastless track on high-speed railway. Vibration-reducing and isolation measures can be adopted for beam section, effectively reducing seismic force and improving overall economy of bridge. The main bridge uses a smaller ratio of mid-span at the edge to meet the requirement of no auxiliary span for flood control, and can effectively reduce the corner at the end of the beam, avoiding the increase of the investment of the whole bridge due to the use of large girder height. When the height of the tower is 38 m, the increase of the height of the tower can significantly reduce the internal force of the beam, but the deformation under temperature load will increase accordingly. Therefore, the selection of the height of the tower should take into account the structural forces and the requirements of track irregularity. AT - 61 cable is used. Increasing cable size has little effect on bridge rigidity, but it can significantly reduce beam bending moment, but increase beam irregularity and residual creep deformation. [ABSTRACT FROM AUTHOR]

The aseismic capability of the water intake tower-traffic bridge, a crucial component of the reservoir's infrastructure, is essential for ensuring the safe operation of the reservoir after an earthquake. Taking the water intake tower-traffic bridge at Shenzhen Beikeng Reservoir as an example, its seismic response was analyzed with finite element method, and its aseismic safety was evaluated. The maximum transverse displacement of the traffic bridge is 3.15 cm, and the minimum distance between adjacent decks is 2.97 cm during the design earthquake. There is no occurrence of beam dropping or collision between adjacent bridge panels. The traffic bridge experiences significant amplification of seismic accelerations in the earthquake. The maximum amplification for the bridge deck's transverse seismic acceleration is 4.01, and for the longitudinal direction, it is 3.36. During the design earthquake, the dynamic shear stress levels in the pier columns of the bridge are not high, indicating that column shear failure is unlikely. However, there are relatively high tensile stress values on the outer vertical side of the bottom of the pier columns. Additionally, the lower beams of the bridge piers exhibit high tensile stress on both the top and bottom surfaces. To ensure the seismic safety of the bridge pier structure, anti-seismic reinforcements are necessary at pier columns and beams. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Due to hydraulic, mechanical, electromagnetic and other reasons, vibration will inevitably occur during the operation of the hydroelectric generating set. As the supporting structure of the hydroelectric generating set, the stability of the pier is very important. In this paper, the whole model of the pier, volute, draft tube and foundation is established. The amplitude of any part of the pier under the resonant load can be obtained by numerical simulation. On this basis, the response surface method is used by statistical method. The two parameters of the inner diameter and thickness of the pier are taken as the design variables, and the information weight method is used to replace the maximum amplitude of the pier in the vertical, radial and circumferential directions with a comprehensive objective function, and the comprehensive objective function is used as the optimization objective. The response surface model is established and the pier model is optimized. The results show that the maximum amplitude of the optimized pier in the vertical direction is reduced by 17.8%, the maximum amplitude in the circumferential direction is reduced by 4.7%, and the maximum amplitude in the radial direction is reduced by 1.4%. The recommended value range of the inner diameter of the pier is 1.73D1 - 1.83D1, and the recommended value range of the pier thickness is 0.50D1 - 0.63D1. The optimization design method of response surface can be effectively applied to the vibration reduction design of hydropower station pier. [ABSTRACT FROM AUTHOR]

In view of the poor flow pattern such as bias flow and vortex in the inlet building of the expansion pump station project, the method of arranging diversion piers is adopted to optimize the flow pattern in the project, but its structural parameters are usually adjusted according to experience, which cannot easily achieve the optimal effect.In order to determine the optimal structural opening parameters of the diversion pier, this study uses the opening length, width, height and spacing of the diversion pier as design variables. The test scheme is designed based on the central composite design method. The axial velocity uniformity is used as the evaluation index. The response surface model is constructed for optimization analysis, and the optimal parameter combination for the opening of the diversion pier is determined. Numerical simulation is carried out under the optimal parameter combination. It is found that the error between the actual value and the predicted value of the response surface model is only 0.33%, and the axial velocity uniformity increases by 11.17% compared with the original scheme, which has significantly improved the flow pattern of the forebay. The results indicate that the established response surface model can reflect the relationship between the evaluation index and the design variables, and the method can be applied to the structural parameter optimization of the rectification measures. [ABSTRACT FROM AUTHOR]

In order to study the influence of shape memory alloy (SMA) on the seismic response of railway self-centering piers, the SMA restrainer element is added to the verified two-spring model. Taking a railway bridge pier as the engineering background, the numerical analysis model is established based on OpenSees platform. By inputting three strong earthquake records, the influence of SMA restrainer on the pier is analyzed by nonlinear time history analysis method. The influence of the initial clearance and the change of the initial prestress of the key parameters of the SMA restrainer device on the displacement of the pier top and the bending moment of the pier bottom is discussed, and compared with the prestressed reinforcement restrainer. The results show that under ordinary ground motion El-Centro and Taft waves, the displacement at the top of the self-centering pier decreases with the decrease of the initial gap δ of the restrainer device, and the bending moment at the bottom of the pier increases with the decrease of the initial gap δ. With the increase of the initial preload of the SMA restrainer, the displacement of the top of the self-centering pier decreases and the bending moment of the bottom of the pier increases. The influence of SMA restrainer on the seismic response of self-centering piers under near-fault ground motion Northridge is complex. Under three strong earthquake records, compared with the prestressed reinforcement restrainer, SMA restrainer will reduce the bending moment of the pier bottom and increase the horizontal displacement of the pier top. [ABSTRACT FROM AUTHOR]

New railways often use frame piers to cross the operating railway. The construction of existing frame piers, especially columns, has a great impact on the operating railway. It is worth studying how to complete the construction quickly and efficiently and reduce the impact on operating railways. In this paper, the rapid construction frame pier is taken as the research object, the research on structure form, connection form, design calculation and construction method is carried out through theoretical analysis, finite element calculation, scheme comparison and engineering application verification. The main research results are as follows: (1) For the rapid construction frame pier, the frame pier beam adopts steel structure, and the column adopts concrete column, steel-concrete composite column, steel column and steel-concrete hybrid column. The full assembly construction can meet the needs of rapid construction of frame piers with different beam span and height. (2) A new type connection of the rapid construction frame pier, between beam and column and between column and foundation, is proposed, which can realize rapid assembly on site. (3) The calculation and analysis show that the strength, rigidity, fatigue and connection performance of the rapid construction frame pier meet the stress requirements. (4) After the successful implementation of some projects, the goal of reducing the impact of construction on the operating railway and reducing the traffic safety risk has been achieved with good promotional value. [ABSTRACT FROM AUTHOR]

In order to meet the development needs of modern traffic, the small radius curved bridge of tramcar has been widely used. Because of the irregular nature of the curved bridge, its seismic response is more intense and complex than that of other bridge types. How to minimize the seismic damage of curved bridge in design is worth in-depth study. Based on a practical project, the three-dimensional finite element models of different pier height arrangements are established. Through nonlinear dynamic time history analysis, the internal force response and displacement response of each pier under the arrangement of equal height, gradient, concave island and convex island are investigated, and some suggestions are put forward for seismic design of curved bridges. Through comparison and analysis, it is shown that in the seismic design of the small radius curved bridge of tram, the equal height layout should be preferred, and the gradient type should be avoided as much as possible, and the necessary seismic reinforcement measures should be taken for the fixed piers in practical engineering. [ABSTRACT FROM AUTHOR]

Pile-pier structures in water level fluctuation zone are very common in the current construction of wharves, trestles, bridges and other structures, and their construction is greatly affected by water level changes, the difficulties and costs are high. Based on the project of a heavy loading wharf in Daya Bay Petrochemical Zone of Huizhou City, a widely applicable method for the construction of partially submerged piers, the reverse lifting base mould construction method, has been proposed. This method can create dryland construction conditions without cofferdam work, which has the advantages of low cost, high construction efficiency and low construction difficulty. Through scheme design and load calculation, it is verified that there verse lifting base mould construction method is feasible theorectially, and finally good results were achieved in the construction of the partially submerged pier of the project involved. [ABSTRACT FROM AUTHOR]

The settlement monitoring and control of high-speed railway (HSR) underline engineering is the basis of realizing the high smoothness construction and high stability operation of railway track. Bridge engineering accounts for more than 50% of the total mileage in the HSR projects that has been established in China. Therefore, it is of great significance for the smooth construction of HSR project and the operation safety of HSR network to carry out settlement monitoring and prediction, so as to realize the rapid and accurate judgment of settlement deformation trend. In order to establish a settlement prediction model that conforms to the actual settlement deformation of HSR piers, the relevant research was carried out based on the autoregressive (AR) model and linear hypothesis theory. Firstly, on the basis of classical AR model, combined with the actual situation of modeling, considering the influence of model variable errors on AR model modeling, the modeling and solution method of autoregressive EIV model for HSR pier settlement prediction considering the model variable errors was derived. Then, the optimum prediction model selection method for HSR pier settlement based on linear hypothesis theory was deduced. Finally, a prediction method of HSR pier settlement based on autoregressive EIV model was designed. The research results show that, the algorithm proposed can be used to establish the optimum settlement prediction model that conforms to the actual settlement deformation of HSR pier, which can objectively and accurately predict the settlement deformation trend of HSR pier, and provide a scientific basis for the construction and operation decision-making. [ABSTRACT FROM AUTHOR]

An existing mooring pier, as a reserved structure, needs to be evaluated for its bearing capacity when the dock is put into use during the upgrading and renovation. A spatial model is established using finite element software SAP2000, and the ultimate bearing capacity of the mooring pier is calculated based on the actual operating conditions and structure of the mooring pier. To verify the reliability of numerical calculations, a prototype test of the mooring pier was designed and implemented. The test used tugboat graded loading, with displacement as the experimental control parameter, effectively solving the problems of reaction force and difficulty in building the observation system. The numerical calculation results are in good agreement with the experimental results, proving that the method for determining the bearing capacity of the mooring pier is reasonable, and the evaluation results meet the requirements of upgrading and renovation. This provides a reference example for the bearing capacity evaluation methods of similar structures. [ABSTRACT FROM AUTHOR]

Copyright of Transportation Science & Technolgy is the property of Transportation Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Under the long-term effect of the flow load the local scour around the bridge pier foundation is extremely prone to occur. Local scour of bridge pier foundation is one of the important factors of bridge failures, and seriously affects the safety and stability of bridges. Therefore, it is especially important to study the local scour reduction measures for bridge piers. As a classical scour reduction measure, the collar can effectively weaken the local scour around the bridge pier foundation. In order to study the local scour reduction around cylindrical bridge piers affected by the collar thickness, a three-dimensional numerical model of pier-flow-sediment is established based on the numerical simulation software Flow-3D. Then the reliability of the model is verified by the Melville classical experimental data, and the validated model is used to study the effect of the change of collar thickness on the local scour depth of bridge piers and the local scour pit morphology of bridge piers. The results show that the scour reduction effect of the collar on the front and rear of the bridge pier is better than that on both sides of the pier. The increase in collar thickness will aggravate the local scour around the bridge pier, especially on both sides of the pier. Under the selected test conditions, the local scour depth around the bridge pier is the smallest, and the scour reduction effect is the best when the collar thickness is 0.05D (D is the diameter of the bridge pier) . The scour reduction efficiency can reach 54.4% at this time. The research findings serve as a reference for the local scour protection of bridge piers. [ABSTRACT FROM AUTHOR]

The liquid bulk cargo berths No.1 and No.2 of East Second Port Pool in Jida Port Area of Maoming Port are independent pier type cylinder caisson gravity wharf. This paper focuses on the precision control of round caisson installation. Under the influence of uncovered conditions and long period waves in the open sea, compared with traditional caisson installation, this project excavates and optimizes from the aspects of ship machinery equipment, selection of lifting point sling, hoisting mode, and takes effective control measures, which greatly improves the accuracy and efficiency of caisson installation, reduces project cost and safety risks of offshore lifting, and provides valuable experience and reference for the installation of independent pier caissons in similar LPG wharves in the future. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Architecture & Civil Engineering is the property of Chang'an Daxue Zazhishe and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To determine the influence of bridge parameters and track parameters on the longitudinal stress and deformation of CWR (Continuous Welded Rail), the pier top longitudinal stiffness limit of 24 m and 32 m simply supported box bridge of intercity railway in Greater Bay Area is determined. Based on the mechanism of the interaction between the beam and track, an integrated finite element model of rail, bridge body and pier is established. The influence of pier top longitudinal stiffness on the tensile and compressive force of CWR, braking force and rapid relative displacement of beam and rail is analyzed. The results show that: The tensile and compressive forces of rail and pier increase with the increase of pier top longitudinal stiffness. The change range of rail's tensile and compressive force is slow, and that of pier's tensile is significant. The increasing rate of both decreases gradually with the increase of pier top longitudinal stiffness. With the increase of the pier top longitudinal stiffness, the braking force at the rail decreases significantly, and the braking force at the pier increases significantly, and the change rate of both decreases gradually. The additional stress of the rail does not affect the determination of the pier top longitudinal stiffness. The rapid relative displacement between beam and rail decreases with the increase of the pier top longitudinal stiffness. Taking the rapid relative displacement of beam and rail as the limiting index, the longitudinal stiffness limit of 32 m single track simply supported box bridge is 125 kN/cm, and that of the 24 m single track simply supported box bridge is 90 kN/cm. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Fly Ash Comprehensive Utilization is the property of Hebei Fly Ash Comprehensive Utilization Magazine Co., Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

It is difficult to build cofferdams in deep waters with shallow overburden and with high risks. Based on the construction of pier No.31 of Xiangluzhou Bridge, a notching+locking steel pipe pile process is proposed to build the cofferdam. Finite element software was used to analyze the cofferdam structure in various construction stages and the calculation results showed that the strength, stiffness and stability of the cofferdam in each construction stage met the design objectives specified in the design criteria. The key technologies for notching in the cofferdam, sand filling in the notched groove, concrete water stop wall and 义pre-shoring method义 are studied to ensure the smooth implementation of the cofferdam. The result of field practice shows that the process is safe and reliable in construction of pile caps in deep waters with shallow overburden and the risk is controllable. [ABSTRACT FROM AUTHOR]

Copyright of Railway Construction Technology is the property of Railway Construction Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aiming at the safety problem of the traverse method construction of copings of thin-walled hollow high piers,a bridge project under construction was taken as the engineering background,and the mechanical characteristics of the construction frame with traverse method of copings was studied. The calculation method of mechanical properties of key combined members were introduced, and the finite element model of the construction frame under the most unfavorable load was developed by using Midas-Civil. The internal force and deformation of the templates pane, main back corrugated, support truss, tension screw, transverse beam, longitudinal beam and cross steel rod were analyzed. The results show that for the formwork system of the traverse method construction of copings, the maximum combined deformation value of is 4. 55 mm, and the maximum combined stress value is 95. 89 MPa. For the support system,the maximum combined stress value is 106. 28 MPa,within the allowable value range. The anti-overturning safety coefficient of the whole structure is 12. 3,which is greater than the minimum safety factor 2. According to the research results, the construction quality of copings was monitored. The on-site monitoring data show that the inspection data of copings is within the specified range,which shows the traverse method construction of copings is safe and reliable [ABSTRACT FROM AUTHOR]

Copyright of Railway Construction Technology is the property of Railway Construction Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Construction Technology is the property of Railway Construction Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Investigation & Surveying is the property of Railway Investigation & Surveying Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Xiamen Second East Passage project is a large fabricated prefabricated bridge project similar to the Hongkong- Zhuhai-Macao Bridge (HZMB) in structure and construction technology. In the construction of post-pouring holes for the piers of the HZMB, the circular steel formwork and wood formwork are used to assemble the formwork, and the process of penetrating the whole rebar after the completion of straight thread sleeves connection is adopted for the rebar. This process has low efficiency, serious damage of epoxy rebar coating when penetrating, and low installation accuracy. In order to improve the construction efficiency and quality, the construction technology of pier prefabrication of Xiamen Second East Passage was improved. In the new technology of post-pouring hole construction, the whole supported and disassembled formwork was adopted for the formwork, and the rebar was adopted for the process of laying rebar. Through the analysis of the key technology of the process, it provides experience for similar project construction in the future. [ABSTRACT FROM AUTHOR]