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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.)

The deteriorated continuous rigid frame bridge is strengthened by external prestressing. Static loading tests were conducted before and after the bridge rehabilitation to verify the effectiveness of the rehabilitation process. The stiffness of the repaired bridge is improved, and the maximum deflection of the load test is reduced from 37.9 to 27.6 mm. A bridge health monitoring system is installed after the bridge is reinforced. To achieve an easy assessment of the bridge's safety status by directly using transferred data, a real-time safety warning system is created based on a five-level safety standard. The threshold for each safety level will be determined by theoretical calculations and the outcomes of static loading tests. The highest risk threshold will be set at the ultimate limit state value. The remaining levels, namely middle risk, low risk, and very low risk, will be determined using reduction coefficients of 0.95, 0.9, and 0.8, respectively. [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.)

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.)

In order to study the effect of bridge pre-camber on the comfort of continuous rigid bridge, a number of continuous rigid bridges with main span diameters between 110 m and 200 m were used as research objects. Firstly, the time domain model of the pavement was established using the filtered white noise method, and the levelness of the new bridge deck was simulated by superimposing it with the formed bridge alignment set according to the co sine curve. Secondly, MATLAB / Simlink was used to build the vehicle-road system model. The root means square (RMS) acceleration value was used to evaluate the traffic comfort of the bridge side span and middle span deck. The maximum transient vibration value (MTVV) was used as the evaluation index of the driving comfort in the short time at the peak of the side span. Finally, the influence of the span diameter and design speed on the RMS value of the side and middle spans of the bridge with the empirical method of setting the pre-arch according to the cosine curve was analyzed. The influence of the pre-arch value on the MTVV value at 3L / 8 of the side span were analyzed. The results showed that the RMS values were less than 0.315 m / s² at the side span and mid-span, indicating that the empirical method of setting the pre-arch of the bridge according to the cosine curve did not affect the traffic comfort at the mid-span. The MTVV value at the side span 3L / 8 was greater than 0.345 m / s² in a short period of time, which mean that the peak of the side span was slightly uncomfortable in a short period of time. In order to improve the traffic comfort within the side span, measures were proposed to optimize the bridge deck alignment at 3L / 8 and the top of the side pier based on the leveling layer construction. [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.)

An innovative seismic performance evaluation strategy for irregular rigid frame bridges with a long-span and high-rise piers under the action of ground motions with different fault distances is presented in this paper. A total of 129 mainshock records taken during the Wenchuan earthquake, from national seismic stations with different fault distances, were analyzed using statistical methods, to determine the attenuation characteristics of the intensity index of the Wenchuan earthquake records from the perspective of aseismic engineering, and the attenuation of the acceleration response spectrum is discussed. The Miaoziping Bridge on the Dujiangyan–Wenchuan Expressway, which was damaged in the Wenchuan earthquake, is taken as the analysis background; two sets of samples for long-span continuous rigid frame bridges with different pier heights are constructed, to discuss the seismic response characteristics of continuous long-span rigid frame bridges; and representative values for the natural periods of these two bridge structural groups are subsequently compared and analyzed. After the peak responses for various bridges with various pier heights are determined through a response spectrum analysis under the action of ground motions with different fault distances, and the surfaces for the obtained peak responses are fitted and the response characteristics for different fault distances are discussed. It is shown in the results that the seismic response characteristics of the continuous rigid frame bridges with long-span and high-rise piers were significantly different under the action of the ground motions with different fault distances, and the seismic responses of these two bridge groups were distinctly larger under the action of near-fault ground motions. Furthermore, based on the above research, suggestions for the pier arrangement and bridge site selection for continuous rigid frame bridges with long-span and high-rise piers are also discussed. The results of this paper also provide some theoretical guidance for the sustainable development of bridges with long-span and high-rise piers, from the perspective of bridge seismic response characteristics. [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.)

This study investigates the mechanical performance of a polyester fiber concrete continuous rigid frame bridge during construction and the spatial stress distribution of the 0# block box girder, with a focus on the backdrop of the bridge in Pipa Zhou, Jiangxi Province. Stress monitoring at critical cross-sections during bridge construction was combined with FE simulations to analyze the stress and alignment deviation variations along the cantilevered construction process of the bridges. Subsequently, after validating the accuracy of the whole bridge model, the actual internal force of the box girder cross-section was extracted to act on the 0# block box girder solid model, and the spatial force of the 0# block box girder under the state of maximal cantilever and the completed bridge was further investigated. The results indicate that during cantilever construction, the top, and bottom plates of the box girder were subjected to compression, with the bottom plates having relatively low compression stress close to the critical values for compression and tension. Attention should be paid to controlling tensile stress application. After reaching a quarter of the bridge's span in construction, the alignment deviation of the main beam increases, necessitating enhanced monitoring and adjustments of the main beam elevation. Furthermore, FE analysis shows that under maximum cantilever and the completed bridge states, the stress variations of the top and bottom plates of the 0# block box girder remain consistent, with the top plate stress varying by no more than 2.5 MPa and the bottom plate stress varying by approximately 1 MPa. Moreover, the 0# block box girder shrinkage cracks were mainly located in the bottom and web plate, and the number of cracks in the 0# block box girder with polyester fibers was reduced compared to the cracks in the ordinary concrete box girder. [ABSTRACT FROM AUTHOR]

Abstract In order to clarify the risk of demolition construction of large-span continuous rigid structure bridge and put forward an intelligent safety assessment method to ensure the safety of demolition construction of the closure segment. Taking a concrete continuous rigid bridge as an example, this paper uses the combination of finite element analysis, theoretical calculation and actual measurement verification to study the influencing parameters and construction safety assessment methods of the long-span continuous rigid bridge in the demolition construction stage of the closure segment. The results show that the parameters that have a great influence on the stress state of box girder and pier during the demolition stage of the closure segment are mainly the self-weight of the structure, tendon prestress state and construction temperature difference. Through the influence envelope analysis of each parameter, it is clear that the ultimate failure mode caused by the most unfavorable parameter combination in the demolition stage of the closure segment is the crushing of the bottom plate of the box girder in the middle span, and the cracking of the piers on the side span at the top and the variable section. In order to further accurately evaluate the construction safety in the demolition stage of the closure segment, based on the long-term down-warping state inversion analysis of the box girder, the identification method of cross-section damage and prestress loss of the box girder and the calculation results of engineering examples are given. Finally, a safety assessment method of the most unfavorable section based on the principle of influence matrix is proposed. Through the analysis of an example, the safety of the closure segment demolition construction is clarified, and the correctness of the analysis is verified by intelligent monitoring means.

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.)

Aiming at the problem of safety assessment of continuous rigid frame bridges, based on the deflection monitoring data, a hierarchical safety evaluation method of continuous rigid frame bridges using evidence theory was proposed. Firstly, the four-level warning mode of the continuous rigid frame bridge was established, and the method of obtaining the warning threshold of each level was proposed, which formed the hierarchical warning framework. On this basis, information fusion was carried out by evidence theory, and the basic reliability distribution function was constructed by means of Euclidean distance. Then, the entropy weight method was used to update the basic reliability distribution, and the Desmpster synthesis rules were used to integrate the evaluation results, thereby realizing the hierarchical evaluation of bridge safety state. Finally, the effectiveness and feasibility of the proposed method was verified by an example analysis. The results show that the proposed method can effectively combine multi-level early warning information, achieve both qualitative and quantitative assessment, and obtain a comprehensive assessment of bridge status. The studied bridge belongs to class 1 evaluation level and is in a good running state. [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.)

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 the construction process of large-scale bridges, there are uncertainties and time-varying factors in the environment and construction loads. It is difficult to make accurate estimates of the theoretical calculation models of construction control in advance. In view of this situation, Bayesian dynamic updating method is introduced to re-estimate the predicted results of the theoretical model. When applying this method, first, the finite element calculation model is determined based on the response surface method, and its calculation results are used as prior information. Then, combined with the actual detection data during the construction process, the Bayesian update formula is derived based on the conjugate prior distribution to correct the theoretical prediction results of bridge construction monitoring. Finally, the actual stress detection data of the control section of high-pier and large-span continuous rigid frame bridges during the construction process illustrate the application process of Bayesian updating in improving the theoretical prediction model. Results indicate that the internal force of the bridge control section obtained by re-evaluating by Bayesian theory not only incorporates the priori information models but also actual monitors sample information during the construction process. The predicted results reflect the true deformation and stress state of the bridge during the bridge construction process and improve the precision of construction monitoring. [ABSTRACT FROM AUTHOR]

In order to clarify the risk of demolition construction of large-span continuous rigid structure bridge and put forward an intelligent safety assessment method to ensure the safety of demolition construction of the closure segment. Taking a concrete continuous rigid bridge as an example, this paper uses the combination of finite element analysis, theoretical calculation and actual measurement verification to study the influencing parameters and construction safety assessment methods of the long-span continuous rigid bridge in the demolition construction stage of the closure segment. The results show that the parameters that have a great influence on the stress state of box girder and pier during the demolition stage of the closure segment are mainly the self-weight of the structure, tendon prestress state and construction temperature difference. Through the influence envelope analysis of each parameter, it is clear that the ultimate failure mode caused by the most unfavorable parameter combination in the demolition stage of the closure segment is the crushing of the bottom plate of the box girder in the middle span, and the cracking of the piers on the side span at the top and the variable section. In order to further accurately evaluate the construction safety in the demolition stage of the closure segment, based on the long-term down-warping state inversion analysis of the box girder, the identification method of cross-section damage and prestress loss of the box girder and the calculation results of engineering examples are given. Finally, a safety assessment method of the most unfavorable section based on the principle of influence matrix is proposed. Through the analysis of an example, the safety of the closure segment demolition construction is clarified, and the correctness of the analysis is verified by intelligent monitoring means. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Fuzhou University is the property of Journal of Fuzhou University, Editorial Department 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.)

More and more rigid frame bridges with high piers and large spans are built in the high and steep slope areas of deep valleys in southwest China. The slow deformation of the slope in the geological sense often causes the problems of piles, which in turn causes damage of the upper bridges. The vertical bearing characteristics of bridge piles in slope still need to be conducted because of the peculiarity of slope topography. The vertical deformation and bearing characteristics of piles in the slope area were experimentally studied by considering different influencing factors and the fitting formula for the ultimate bearing capacity of the piles under vertical load is obtained. The results show that the vertical deformation and ultimate bearing capacity (defined by vertical limit settlement deformation of 0.013 times the pile diameter) of the pile are closely related to its position in the slope. The pile in the middle of the slope has the lowest vertical ultimate bearing capacity. Moreover, the side frictional resistance transfer depth of the pile in continuous slope is greater than that of the pile in unilateral slope. Additionally, the slope angle has a significant influence on the vertical bearing performance of piles. The delayed settlement of the pile top decreases approximately 40% at most and the vertical ultimate bearing capacity of the pile increases 48.6% at most as the slope angle decreases by 15°. Meanwhile, the side friction resistance of the pile increases with the decrease of slope angle. The bending moment applied to the pile top reduces the vertical ultimate bearing capacity of the pile and increases the axial force of the pile body. The results can provide data support for pile design and instability judgment with similar geological conditions. [ABSTRACT FROM AUTHOR]

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.)

This study investigates the mechanical performance of a polyester fiber concrete continuous rigid frame bridge during construction and the spatial stress distribution of the 0# block box girder, with a focus on the backdrop of the bridge in Pipa Zhou, Jiangxi Province. Stress monitoring at critical cross-sections during bridge construction was combined with FE simulations to analyze the stress and alignment deviation variations along the cantilevered construction process of the bridges. Subsequently, after validating the accuracy of the whole bridge model, the actual internal force of the box girder cross-section was extracted to act on the 0# block box girder solid model, and the spatial force of the 0# block box girder under the state of maximal cantilever and the completed bridge was further investigated. The results indicate that during cantilever construction, the top, and bottom plates of the box girder were subjected to compression, with the bottom plates having relatively low compression stress close to the critical values for compression and tension. Attention should be paid to controlling tensile stress application. After reaching a quarter of the bridge’s span in construction, the alignment deviation of the main beam increases, necessitating enhanced monitoring and adjustments of the main beam elevation. Furthermore, FE analysis shows that under maximum cantilever and the completed bridge states, the stress variations of the top and bottom plates of the 0# block box girder remain consistent, with the top plate stress varying by no more than 2.5 MPa and the bottom plate stress varying by approximately 1 MPa. Moreover, the 0# block box girder shrinkage cracks were mainly located in the bottom and web plate, and the number of cracks in the 0# block box girder with polyester fibers was reduced compared to the cracks in the ordinary concrete box girder.

Bridges are critical links in a transportation network that are susceptible to seismic actions, their vulnerability assessment is essential for seismic risk assessment and mitigation. In order to explore the damage probability of long span prestressed concrete continuous rigid frame bridge in the event of earthquake, this study took the Longxi Jialing River Bridge as an example and presents seismic vulnerability assessment based on the incremental dynamic analysis method. Taking the curvature of the pier's most unfavorable section as the damage index, the seismic vulnerability curve of the pier was established with peak acceleration(PGA) as the independent variable and the probability of the structure exceeding a specific damage state as the dependent variable. Results demonstrate that under the action of a near-field earthquake, when PGA =0.5 g, the failure probabilities of slight damage is 0.02926, the failure probabilities of moderate damage is 0.01823, and the failure probabilities of severe damage is 0.00075. When PGA = 1.0 g, the failure probabilities of slight damage is 0.672 and 0.597 for moderate damage, 0.20109 for severe damage, and 0.00484 for complete damage. Under the action of a far-field earthquake, when PGA = 0.5 g, the failure probability of slight damage is 0.00194, and the failure probability of moderate damage is 0.00101 along the span direction. When PGA = 1.0 g, the failure probability of slight damage is 0.04358, 0.02802 for moderate damage, and 0.00138 for serious damage along the span direction. The complete damage of the bridge hardly occurs. With the increase of intensity of an earthquake, the failure probability of the pier gradually increases. After entering the moderate damage stage, the pier has relatively good ductility. This study provides a good reference for the seismic design of similar bridges. [ABSTRACT FROM AUTHOR]

This paper summarizes a sophisticated field investigation of the seismic damage to a continuous rigid frame bridge. Cracking and deformation of main girder, failure of bearings, and damage of piers were examined. The whiplash effect of the long side span of main bridge caused the prominent damage of bearings and restrainers on the transition piers. A numerical model was developed for supplementary analysis. The multi-directional dynamic analyses were conducted, which revealed a satisfactory agreement with the field investigation. Based on the numerical model, the effect of anti-tensile configurations was analyzed for reducing the whiplash effect of the side span. [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.)

In the construction process of large-scale bridges, there are uncertainties and time-varying factors in the environment and construction loads. It is difficult to make accurate estimates of the theoretical calculation models of construction control in advance. In view of this situation, Bayesian dynamic updating method is introduced to re-estimate the predicted results of the theoretical model. When applying this method, first, the finite element calculation model is determined based on the response surface method, and its calculation results are used as prior information. Then, combined with the actual detection data during the construction process, the Bayesian update formula is derived based on the conjugate prior distribution to correct the theoretical prediction results of bridge construction monitoring. Finally, the actual stress detection data of the control section of high-pier and large-span continuous rigid frame bridges during the construction process illustrate the application process of Bayesian updating in improving the theoretical prediction model. Results indicate that the internal force of the bridge control section obtained by re-evaluating by Bayesian theory not only incorporates the priori information models but also actual monitors sample information during the construction process. The predicted results reflect the true deformation and stress state of the bridge during the bridge construction process and improve the precision of construction monitoring.

The pounding effect at the expansion joints on the seismic response of a long-span deep-water high pier bridge with multiple approach spans under earthquake is studied considering the fluid–structure interaction effect. The nonlinear fibre element is used to simulate the main piers and transition piers. The contact element is employed to consider the seismic pounding effect at the expansion joints. The hydrodynamic pressure is applied to the main piers and transition piers in the form of added mass of graded accumulation. Forty seismic records of different earthquakes are used as input to conduct the longitudinal time history analysis of the whole bridge. The seismic responses of bridge structure with and without pounding effect are compared to analyse the impact of pounding on the structure. The results show that considering the pounding effect at the expansion joints, the seismic response of the main pier under the fluid–structure interaction effect is reduced, which indicates that the pounding is beneficial to the main pier. Due to the out-of-phase vibration between the main bridge and the approach spans, the pounding force at the expansion joints on the left and right transition piers is the largest, and the pounding transmission effect is obvious. The transmission effect makes the positive displacement amplitude of the right bearings on the top of each pier of the right approach spans increase evidently. The increased amplitude of each pier is not synchronous, which will increase the possibility of unseating. [ABSTRACT FROM AUTHOR]

Structural health monitoring (SHM) allows for real-time structural response monitoring and online data acquisition of bridge structures. Thisdata reflectsthe operational and environmental conditions of the bridge, which is important in identification of possible anomalous changes. In order to effortlessly determine the safety condition of the bridge directly through the transferred data without data analysis, a five-level safety standard system will be established for real-time safety warning in this paper. The threshold of each safety levels will be determined through field loading tests results on an external prestressing rehabilitated continuous rigid frame bridge, of which permanent structural health monitoring system was instrumented. After overall evaluation, we cometo the conclusionthat the rehabilitation is successful and that the bridge is under safe operating condition.A novel, simplified safety standard thresholding technique is proposed based on static loading test results as well as ultimate limit state of the bridge. This technique is simple yet very practical in daily bridge monitoring.

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil 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 Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil 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.)

Near-fault pulse-type (NFPT) ground motion is characterized by pronounced velocity pulse effects. Its velocity pulse period is typically greater than 1 s, and has a large influence on the seismic response of long-period bridges. However, few quantitative studies about the influence of the pulse parameters have been reported. In this work, that influence – namely, velocity pulse period (VPP), velocity pulse amplitude (VPA), and velocity pulse number (VPN) – on the seismic response of a long-period bridge was studied. A 1/15-scale model was designed and a synthetic method was introduced to obtain artificial NFPT ground motions. Then, a series of shaking table tests and numerical simulation analyses were conducted. The results show that the synthetic method can be used to obtain artificial NFPT ground motions for different pulse parameters. The pulse effect can significantly increase the seismic response of the model bridge. The response increases as VPA increases. In the case of the increasing VPP, the response first increases and then decreases. It may be greater when the VPP is close to the natural vibration period of the model. The displacement response spectrum value can be used to predict the influence of the VPN. A larger spectrum value can induce a larger response. [ABSTRACT FROM AUTHOR]

To consider the effect of non-uniform shrinkage of box girder sections on the long-term deformations of continuous rigid frame bridges, and to improve the prediction accuracy of analysis in the design phase, this paper proposes a new simulation technique for use with general-purpose finite element program. The non-uniform shrinkage effect of the box girder is transformed to an equivalent temperature gradient and then applied as external load onto the beam elements in the finite element analysis. Comparative analysis of the difference in deflections between uniform shrinkage and nonuniform shrinkage of the main girder was made for a vehicular bridge in reality using the proposed technique. The results indicate that the maximum deflection of box girder under the action of non-uniform shrinkage is much greater than that under the action of uniform shrinkage. The maximum downward deflection of the bridge girder caused by uniform shrinkage is 5.6 mm at 20 years after completion of bridge deck construction, whereas the maximum downward deflection caused by non-uniform shrinkage is 21.6 mm, which is 3.8 times larger. This study shows that the non-uniform shrinkage effect of the girder sections has a significant impact on the long-term deflection of continuous rigid frame bridge, and it can be accurately simulated by the proposed transformation technique.

Four seismic isolation specimens were designed, fabricated, and subjected to physical loading tests to enhance the seismic performance of a high-pier continuous rigid-frame bridge. A finite element model of the seismic isolation structure of the high-pier was established using numerical simulation software. The entire bridge model was established based on the multi-scale modeling method to investigate the seismic response of the high-pier continuous rigid frame bridge under different seismic waves. The results indicate that the seismic isolation pier has self-centering and energy dissipation capabilities. The seismic isolation pier has satisfactory energy dissipation capacity and ductility when the ratio of the long-axis and short-axis radii is 1.5. The results of the finite-element simulation corresponded well with the experimental results. Significant damage occurred to the concrete at the bottom and corner of the pier, and the reinforcement did not reach its yield strength throughout the loading process. Therefore, measures must be implemented to ensure the seismic performance of the structure. The pier bottom self-centering seismic isolation structure effectively absorbs shocks, as evidenced by reduced absolute acceleration and relative displacement at the pier top, decreased shear force and bending moment at the pier bottom, and minimized girder displacement. It was recommended that the ratio of the long-axis and short-axis radii be adopted as 1.5–2.0 and that the pier height be selected as 60 m–100 m. These results provide a reference for the research and applications of this type of structure. • Seismic isolation specimens enhance high-pier bridge's seismic performance. • Experimental and simulation results align for seismic isolation pier. • Seismic isolation pier exhibits self-centering and energy dissipation. • Ratio of long-axis to short-axis radii affects energy dissipation. • Pier bottom self-centering structure absorbs shocks effectively. [ABSTRACT FROM AUTHOR]

In this paper, we study the application of BIM technology in the construction management of prestressed concrete continuous rigid frame bridge as well as the design and installation of travelling trestle bridge fabrication machine based on the Xingbei Weihe River Bridge Project. Abaquss can be used for checking the safety of the design. Delmia can be used for the hoisting simulation of the main girder of the die frame and determining the lifting lug position of the main girde. Revit is applicable to the establishment of the model of continuous rigid road bridge, to optimize the design drawings through collision inspection, meanwhile, accurate engineering quantity and construction coordinates can be extracted to serve the construction management. The BIM platform turns out to be good for bridge construction quality and safety and engineering data management, which not only improves management efficiency, but also facilitates data search and provides data support for later operations. [ABSTRACT FROM AUTHOR]

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil 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 Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil 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 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.)

To investigate the seismic fragility of deep-water and high-pier continuous rigid frame bridge subjected to the combined action of hydrodynamic pressure and ground motion, a representative deep-water and high-pier continuous rigid frame bridge is examined to study the influence of hydrodynamic pressure and ground motion on structural fragility. The corresponding damage indicators and conditional exceedance probabilities are defined and quantified. The probabilistic seismic demand model (e.g., pier and bearing) is analyzed using incremental dynamic analysis (IDA) in the nonlinear finite element software OpenSEES. A comparative analysis is conducted to identify the effect of hydrodynamic pressure on the dynamic response of the bridge. Hydrodynamic pressure plays an important role in influencing the conditional failure probability of piers and bearings. Damage probability increases with increasing water depth, particularly for the pier top in the longitudinal direction. • The hydrodynamic pressure of piers is considered via the "added mass" of piers obtained. • The fragility curves of two models with and without hydrodynamic pressure are derived and compared. • The damage exceedance probability of pier with hydrodynamic pressure is significantly greater. [ABSTRACT FROM AUTHOR]

This paper is concerned with the evaluation of natural frequencies for the design of simply supported girder bridges, continuous girder bridges, and continuous rigid frame bridges. There are two significant parameters affecting the vibration frequencies. The first parameter is called the span ratio γ while the second parameter is called the stiffness ratio κ. The approximate formulas in terms of these parameters are proposed for these three types of bridges. From the analysis results, it is found that the first mode shape of the continuous rigid frame bridge is mainly induced by the pier other than the superstructure, when the stiffness parameter κ is greater than 10. Finally, the method proposed herein may be adopted to investigate the natural frequency of other types of bridges. [ABSTRACT FROM PUBLISHER]

The large-span continuous rigid frame bridge is a kind of common structural form in long-span bridges of our country, but one of the main diseases of these bridges is the excessive deflection in the mid-span, which seriously affects the safety of the structure. This paper makes a comprehensive analysis for the causes of the excessive deflection, and lists the commonly-used control measures in engineering. Simultaneously, new improvement measures and the comparative analysis of before-and-after improvements are put forward on this basis. However, these measures can be used to inhibit deflection in a certain extent, but cannot avoid the occurrence of deflection completely.