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Discussion on Detection and Evaluation of Simply Supported Prestressed Concrete Small Box Girder Bridge After a Fire
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作者 Qing Yang Jiang Feng 《Journal of Architectural Research and Development》 2024年第2期108-113,共6页
The article takes a simply supported prestressed concrete small box girder bridge project as an example for inspection and evaluation after a fire incident.This includes appearance detection,concrete color hardness de... The article takes a simply supported prestressed concrete small box girder bridge project as an example for inspection and evaluation after a fire incident.This includes appearance detection,concrete color hardness detection,concrete strength detection,concrete surface damage layer detection,reinforcement protective layer detection,and concrete carbonation detection.It is hoped that this analysis can be used as a reference for the detection and evaluation of future bridge projects with fire incidents to smoothen its subsequent repair and maintenance. 展开更多
关键词 prestressed concrete box girder Simply supported small box girder Fire damage concrete testing Reinforcement testing
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Design on the Prestressed Concrete Frame Beam-column
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作者 ZHANG Taiyue ZHANG Weiguo +1 位作者 WANG Sihai GUO Yiqing 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第6期1397-1403,共7页
A bidirectional ribbed concrete beam slab structure was widly adopted for the upper space of industrial buildings.To maintain ample space and minimize the presence of conventional columns,a bidirectional prestressed c... A bidirectional ribbed concrete beam slab structure was widly adopted for the upper space of industrial buildings.To maintain ample space and minimize the presence of conventional columns,a bidirectional prestressed concrete beam is often employed.The intersection node of the prestressed concrete frame beam column was characterized by a high density of steel reinforcement,significant structural loads,and complex construction requirements.To ensure the quality,safety,and progress of prestressed frame beamcolumn intersection nodes during construction,this article proposed a new technology for constructing such nodes,which includes setting the tensioning and haunching ends of nodes at different positions,using ABAQUS finite element software to optimize the design of cross-sectional dimensions,conducting stress analysis simulations. 展开更多
关键词 prestressed concrete beam-column intersection node finite element analysis optimal design digital simulation
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Finite element failure analysis of continuous prestressed concrete box girders 被引量:4
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作者 张峰 李术才 +2 位作者 李树忱 叶见曙 雷笑 《Journal of Southeast University(English Edition)》 EI CAS 2009年第2期236-240,共5页
In order to analyze the load carrying capacity of prestressed concrete box girders, failure behaviors of in-situ deteriorated continuous prestressed concrete box girders under loading are experimentally observed and a... In order to analyze the load carrying capacity of prestressed concrete box girders, failure behaviors of in-situ deteriorated continuous prestressed concrete box girders under loading are experimentally observed and a finite failure analysis method for predicting behaviors of box girders is developed. A degenerated solid shell element is used to simulate box girders and material nonlinearity is considered. Since pre-stressed concrete box girders usually have a large number of curve prestressed tendons, a type of combined element is presented to simulate the prestressed tendons of box girders, and then the number of elements can be significantly reduced. The analytical results are compared with full-scale failure test results. The comparison shows that the presented method can be effectively applied to the failure analysis of in-situ continuous prestressed concrete box girders, and it also shows that the studied old bridge still has enough load carrying capacity. 展开更多
关键词 full-scale failure test prestressed concrete box girder finite element analysis combined element prestressed tendon load carrying capacity
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Durability design of prestressed concrete structures 被引量:4
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作者 涂永明 吕志涛 《Journal of Southeast University(English Edition)》 EI CAS 2005年第1期73-77,共5页
Based on the durability characteristics of prestressed concrete structures,the durability limit states of carbonation and chloride ion attack are defined, respectively.Durability predicting models on the basis of reli... Based on the durability characteristics of prestressed concrete structures,the durability limit states of carbonation and chloride ion attack are defined, respectively.Durability predicting models on the basis of reliability mathematics and stochastic processes areconstructed, and the pure theoretical formulae of failure probability of prestressed concretestructures are analyzed. In addition, a simple durability design method for carbonation ofstructures is put forward. According to the analysis, the durability of prestressed concretestructures is superior to that of traditional structures. The research also indicates that theconcrete cover prescribed in the current code (GB 50010-2002) is not adequate. The rational coverthickness should notbe less than 35 or 45 mm according to carbonation or chloride ion attack,respectively. 展开更多
关键词 prestressed concrete structure limit state failure probability durabilitydesign
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Study on the Design Criteria for Prestressed Concrete Pavements
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作者 孙宝俊 RogerK.Hawkins 吕志涛 《Journal of Southeast University(English Edition)》 EI CAS 2000年第1期80-88,共9页
With a concrete pavement slab prestressed, its load carrying capacity can be significantly increased; thus a thinner slab may be used for the same loading. Prestressing modify the structural behavior of the pavement ... With a concrete pavement slab prestressed, its load carrying capacity can be significantly increased; thus a thinner slab may be used for the same loading. Prestressing modify the structural behavior of the pavement slab and there is a greater resistance to impact, vibration and overloading. This paper discusses the major design considerations necessary in the successful construction of prestressed concrete pavements and presents a design procedure developed to predict the compressive stress due to prestressing in the pavements at early stage, during service and after cracking. Variation in the approach for repetitive and nonrepetitive loads is clearly distinguished. Check on the recovery after cracking for overloading in prestressed pavements is also needed. Finally, a design example is illustrated the application of the approach developed. 展开更多
关键词 design criteria prestressed concrete pavements design procedure prestressING recovery after cracking
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Dynamic finite element model updating of prestressed concrete continuous box-girder bridge 被引量:6
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作者 Lin Xiankun Zhang Lingmi +1 位作者 Guo Qintao Zhang Yufeng 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2009年第3期399-407,共9页
The dynamic finite element model (FEM) of a prestressed concrete continuous box-girder bridge, called the Tongyang Canal Bridge, is built and updated based on the results of ambient vibration testing (AVT) using a... The dynamic finite element model (FEM) of a prestressed concrete continuous box-girder bridge, called the Tongyang Canal Bridge, is built and updated based on the results of ambient vibration testing (AVT) using a real-coded accelerating genetic algorithm (RAGA). The objective functions are defined based on natural frequency and modal assurance criterion (MAC) metrics to evaluate the updated FEM. Two objective functions are defined to fully account for the relative errors and standard deviations of the natural frequencies and MAC between the AVT results and the updated FEM predictions. The dynamically updated FEM of the bridge can better represent its structural dynamics and serve as a baseline in long-term health monitoring, condition assessment and damage identification over the service life of the bridge . 展开更多
关键词 prestressed concrete continuous box-girder bridge field ambient vibration testing dynamic characteristics model updating accelerating genetic algorithm objective function
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Temperature and Stress Analysis of An Experimental Model of Prestressed Lightweight Concrete Platform 被引量:2
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作者 宋玉普 宋小软 封盛 《China Ocean Engineering》 SCIE EI 2000年第3期279-288,共10页
This paper presents an experimental study of a prestressed lightweight concrete platform model with a tank and for five steel-columns. This platform can be used not only for extraction but also for storage of oil and ... This paper presents an experimental study of a prestressed lightweight concrete platform model with a tank and for five steel-columns. This platform can be used not only for extraction but also for storage of oil and is suitable for the Bohai Sea and other shallow seas of China. The platform is subjected to temperature. load, or both. The corresponding temperature distribution. strains, cracks. and vulnerable parts of the platform are analyzed respectively. By use of the finite element method and empirical formulas, the temperature field of the model is analyzed. The results agree with the experimental results, thereby verifying! the reliability of these two calculating methods. The paper provides an experimental basis for the des sign of the bearing capacity and normal service state of prestressed concrete platforms. 展开更多
关键词 prestressed concrete platform LIGHTWEIGHT TEMPERATURE STRAIN cracks
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Theoretical analysis of natural frequency of externally prestressed concrete beam based on rigidity correction 被引量:3
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作者 Hui-xia Xiong1,2, Yao-ting Zhang11.School of Civil Engineering & Mechanics, Huazhong University of Science and Technology, Wuhan 430074, China 2.Department of Civil Engineering, Nanyang Institute of Technology, Nanyang 473004, China. 《Journal of Pharmaceutical Analysis》 SCIE CAS 2009年第1期31-35,共5页
A dynamic test on externally prestressed simply supported concrete beams separately with three typical types of tendon distributions was conducted. The results show that the natural frequencies of the beams increase w... A dynamic test on externally prestressed simply supported concrete beams separately with three typical types of tendon distributions was conducted. The results show that the natural frequencies of the beams increase with the increase in the prestressing force at the tensioning stage, and the natural frequencies decrease after the cracks occur in the beams. Following the calculation formula of natural frequency of externally prestressed beam, which was reported in a literature, the natural frequencies of the experimental beams are calculated, and big errors are found between the test results and the calculated ones of natural frequency values. As a result, this paper has tried to adopt two methods to correct the rigidity parameter of the concrete beam in the formula for natural frequency calculation, and to use the corrected formula to calculate the frequencies of the experimental beams. The calculation results indicate a good consistency with the experimental ones, which verifies the feasibility of the corrected formula. 展开更多
关键词 externally prestressed concrete beam natural frequency rigidity correction regression analysis
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Influence of key factors on deflection of bonded prestressed concrete simply supported slabs subjected to fire 被引量:3
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作者 郑文忠 欧阳志为 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2010年第5期615-621,共7页
In order to validate the accuracy of nonlinear fire simulation programs,comparison analysis is carried out between simulation and experiment induced from small-scale specimens,and then fire resistance of large-scale p... In order to validate the accuracy of nonlinear fire simulation programs,comparison analysis is carried out between simulation and experiment induced from small-scale specimens,and then fire resistance of large-scale prestressed concrete slabs is further investigated through parameter expansion.The influences on fire resistance ratings controlled by deflection are explored and discussed,including effective span,concrete cover thickness,load level,prestress degree,effective prestress,composite reinforcement index and other factors.The calculated results indicate that fire resistance ratings of large-scale bonded prestressed concrete simply supported slabs are bigger than those of small-scale ones.Finally,the calculation formulas of fire resistance ratings controlled by deflection are established,which rationally consider the influence of effective span,concrete cover thickness,load level,composite reinforcement index and so on key factors. 展开更多
关键词 bonded prestressed concrete simply supported slabs fire resistance ratings controlled by deflection
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Structural Behavior of Continuous Prestressed Steel Fiber Reinforced High Strength Concrete Beam 被引量:2
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作者 刘海波 向天宇 赵人达 《Journal of Southwest Jiaotong University(English Edition)》 2008年第1期37-45,共9页
The flexural behaviors of continuous fully and partially prestressed steel fiber reinforced high strength concrete beams are studied by experiment and nonlinear finite element analysis. Three levels of partial prestre... The flexural behaviors of continuous fully and partially prestressed steel fiber reinforced high strength concrete beams are studied by experiment and nonlinear finite element analysis. Three levels of partial prestress ratio (PPR) are considered, and three pairs of two-span continuous beams with box sections varying in size are designed. The major parameters involved in the study include the PPR and the fiber location. It is concluded that the prestressed high strength concrete beam exhibits satisfactory ductility; the influences of steel fiber on the crack behaviors for partially prestressed beams are not as obvious as those for fully prestressed ones; steel fibers can improve the structural stiffness after cracking for fully prestressed high strength concrete beams; the moment redistribution from mid-span to intermediate support in the first stage should be mainly considered in practical design. 展开更多
关键词 High strength concrete Steel fiber reinforced concrete prestressed concrete Continuous beam
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Fatigue Damage Modeling for Partially Prestressed Concrete Beams under Repeated Loadings with Variable Amplitude 被引量:2
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作者 冯秀峰 宋玉普 朱美春 《Journal of Southwest Jiaotong University(English Edition)》 2006年第3期258-264,共7页
A full-range nonlinear analysis method for fatigue damage in prestressed concrete beams is presented. New damage accumulation models are proposed to describe the fatigue damage evolution in concrete and reinforcement ... A full-range nonlinear analysis method for fatigue damage in prestressed concrete beams is presented. New damage accumulation models are proposed to describe the fatigue damage evolution in concrete and reinforcement respectively. Based on the stress analysis for cross section, the stress redistrbution in the fatigue damage process, due to the different damage mechanisms of concrete and reinforcement, is considered. The nonlinear damage analysis is achieved by means of piecewise linearity, and it is applicable on the condition of repeated loadings with variable amplitude. Fatigue damage modeling of a beam is implemented to illustrate that the proposed method can preferably fit the experimental results. 展开更多
关键词 prestressed concrete beam FATIGUE DAMAGE Nonlinear analysis Stress redistribution
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Load history-based model for prestressed concrete beam damage evaluation 被引量:1
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作者 袁建力 王仪 钱仲慧 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2007年第4期383-390,共8页
The residual capability of a damaged structure to resist further load is essential in optimal seismic design and post-earthquake strengthening. An experimental study on the hysteretic characteristics of prestressed co... The residual capability of a damaged structure to resist further load is essential in optimal seismic design and post-earthquake strengthening. An experimental study on the hysteretic characteristics of prestressed concrete frame beams under different loading histories was performed to explore the influence of load history on energy dissipation and failure characteristics of the member. Based on the test results, the failure of the beam is defined, and the relationship between the failure moment under cyclic load and from the skeleton curve is formulated. Finally, based on displacement and energy dissipation, a model for prestressed concrete beam damage-failure evaluation is developed. In this model, the effect of deformation level, cumulative dissipated energy, and loading history on prestressed concrete beam damage-failure is incorporated, thus it is applicable to stochastic earthquake forces. 展开更多
关键词 prestressed concrete earthquake force load history energy dissipation damage-failure evaluation
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Experimental and analytical studies on the vibration serviceability of long-span prestressed concrete floor 被引量:1
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作者 Cao Liang Liu Jiepeng +1 位作者 Li Jiang Zhang Ruizhi 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2018年第2期417-428,共12页
An extensive experimental and theoretical research study was undertaken to study the vibration serviceability of a long-span prestressed concrete floor system to be used in the lounge of a major airport.Specifically,j... An extensive experimental and theoretical research study was undertaken to study the vibration serviceability of a long-span prestressed concrete floor system to be used in the lounge of a major airport.Specifically,jumping impact tests were carried out to obtain the floor’s modal parameters,followed by an analysis of the distribution of peak accelerations.Running tests were also performed to capture the acceleration responses.The prestressed concrete floor was found to have a low fundamental natural frequency(≈8.86 Hz)corresponding to the average modal damping ratio of≈2.17%.A coefficients plate with simply-supported edges.The calculated analytical results(natural frequencies and root-mean-square acceleration)agree well with the experimental ones.The analytical approach is thus validated. 展开更多
关键词 vibration serviceability prestressed concrete floor airport lounge theoretical analysis modal superposition method
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Aseismic safety analysis of a prestressed concrete containment vessel for CPR1000 nuclear power plant 被引量:1
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作者 Yi Ping Wang Qingkang Kong Xianjing 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2017年第1期55-67,共13页
Abstract: The containment vessel of a nuclear power plant is the last barrier to prevent nuclear reactor radiation. Aseismic safety analysis is the key to appropriate containment vessel design. A prestressed concrete... Abstract: The containment vessel of a nuclear power plant is the last barrier to prevent nuclear reactor radiation. Aseismic safety analysis is the key to appropriate containment vessel design. A prestressed concrete containment vessel (PCCV) model with a semi-infinite elastic foundation and practical arrangement of tendons has been established to analyze the aseismic ability of the CPR1000 PCCV structure under seismic loads and internal pressure. A method to model the prestressing tendon and its interaction with concrete was proposed and the axial force of the prestressing tendons showed that the simulation was reasonable and accurate. The numerical results show that for the concrete structure, the location of the cylinder wall bottom around the equipment hatch and near the ring beam are critical locations with large principal stress. The concrete cracks occurred at the bottom of the PCCV cylinder wall under the peak earthquake motion of 0.50 g, however the PCCV was still basically in an elastic state. Furthermore, the concrete cracks occurred around the equipment hatch under the design internal pressure of 0.4MPa, but the steel liner was still in the elastic stage and its leak-proof function soundness was verified. The results provide the basis for analysis and design of containment vessels. 展开更多
关键词 nuclear power plant prestressed concrete containment vessel aseismic safety analysis
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Experimental Behavior of Partially Prestressed High Strength Concrete Beams 被引量:3
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作者 Shady H. Salem Khalid M. Hilal +1 位作者 Tarek K. Hassan Ahmed S. Essawy 《Open Journal of Civil Engineering》 2013年第3期26-32,共7页
In the last few decades, prestressed concrete has been rapidly used in bridge engineering due to the enormous development in the construction techniques and the increasing need for long span bridges. High strength con... In the last few decades, prestressed concrete has been rapidly used in bridge engineering due to the enormous development in the construction techniques and the increasing need for long span bridges. High strength concrete has been also more widely spread than the past. It currently becomes more desirable as it has better mechanical properties and durability performance. Major defect of fully prestressed concrete is its low ductility;it may produce less alarming signs than ordinary reinforced concrete via smaller deflection and limited cracking. Therefore, partially prestressing is considered an intermediate design between the two extremes. So, combining high strength concrete with partial prestressing will result in a considerable development in the use of prestressed concrete structures regarding the economical and durability view points. This study presents the results of seven partially prestressed high strength concrete beams in flexure. The tested beams are used to investigate the influence of concrete compressive strength, prestressing steel ratio and flange width on the behavior of partially prestressed beams. The experimentally observed behaviors of all beams were presented in terms of the cracking load, ultimate load, deflection, cracking behavior and failure modes. 展开更多
关键词 PARTIALLY prestressed High Strength concrete BEAMS SERVICEABILITY BEHAVIOR Failure Modes
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Experimental research on mechanical properties of prestressed truss concrete composite beam encased with circular steel tube 被引量:3
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作者 张博一 郑文忠 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第3期338-345,共8页
Tests of 4 simply supported unbonded prestressed truss concrete composite beams encased with circular steel tube were carried out. It is found that the ratio of the stress increment of the unbonded tendon to that of t... Tests of 4 simply supported unbonded prestressed truss concrete composite beams encased with circular steel tube were carried out. It is found that the ratio of the stress increment of the unbonded tendon to that of the tensile steel tube is 0.252 during the using stage,and the average crack space of beams depends on the ratio of the sum of the bottom chord steel tube's outside diameter and the secondary bottom chord steel tube's section area to the effective tensile concrete area. The coefficient of uneven crack distribution is 1.68 and the formula for the calculation of crack width is established. Test results indicate that the ultimate stress increment of unbonded tendon in the beams decreases in linearity with the increase of the composite reinforcement index β0. The pure bending region of beams accords with the plane section assumption from loading to failure. The calculation formula of ultimate stress increment of the unbonded tendon and the method to calculate the bearing capacity of normal section of beams have been presented. Besides,the method to calculate the stiffness of this sort of beams is brought forward as well. 展开更多
关键词 truss concrete composite beam encased with circular steel tube bearing capacity of normal section STIFFNESS crack width unbonded prestressed tendon
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Analysis and calculation of factors on curvature ductility of unbonded prestressed concrete beams 被引量:1
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作者 郑文忠 解恒燕 杨春峰 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第1期18-22,共5页
In consideration that behavior of curvature ductility of interior support directly influences the degree of moment modification of unbonded prestressed concrete (UPC) continuous structures, constitutive relationships ... In consideration that behavior of curvature ductility of interior support directly influences the degree of moment modification of unbonded prestressed concrete (UPC) continuous structures, constitutive relationships of concrete, non-prestressed reinforcement and prestressed reinforcement used for nonlinear analysis are given. Through simulation analysis on simple beams subjected to single loading at the middle of the span, the law of factors influencing curvature ductility, such as global reinforcing index, prestressing degree, effective prestress, strength of concrete and grade of non-prestressed reinforcement are explored. Based on these researches, calculating formula of curvature ductility coefficient of UPC beams is established, which provides basic data for further research on plastic design of UPC indeterminate structures. 展开更多
关键词 unbonded prestressed concrete continuous beam curvature ductility coefficient global reinforcing index
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Experimental and theoretical analysis on the natural frequency of external prestressed concrete beams 被引量:1
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作者 熊辉霞 《Journal of Chongqing University》 CAS 2008年第4期317-323,共7页
Analyses and computations of the natural frequencies of external prestressed concrete structures are the bases for studying the dynamic properties of such structures. We carded out dynamic tests on three types of exte... Analyses and computations of the natural frequencies of external prestressed concrete structures are the bases for studying the dynamic properties of such structures. We carded out dynamic tests on three types of external simply supported beams, pulling the beams gradually. Then vertical loads were applied to the beams while the frequencies and related coefficients were measured at every step. We calculated natural frequencies and the results indicate that natural frequencies increase as the prestressing force rises in the pre-crack stage, and decrease significantly during the post-crack stage. Substantial incoincidences exist between the calculated and experimental results for the frequency and its tendency to changel Based on the experimental results, we modified the stiffness and other parameters in the equations. The results calculated using the modified equations agree with experimental results well, so the modified eauations can be used nractically. 展开更多
关键词 natural frequency external prestressed concrete beams dynamic property stiffness modification
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METHOD FOR FAST TEST OF PRESTRESSED CONCRETE VOIDED SLAB (V.S)
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作者 马明奎 孙长林 周儒祥 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1996年第1期92-94,共3页
By practical experience and lots of actuel data on tens of prestressed concrete V.S,maximum strains of the midspan sectional concrete and Strains of tendon are calculated according to actual date of the midspan deflec... By practical experience and lots of actuel data on tens of prestressed concrete V.S,maximum strains of the midspan sectional concrete and Strains of tendon are calculated according to actual date of the midspan deflection Yc, which show Whole structual working condition, as a result,method for fast test of structural bearing capacity can be deduced, which would make determining bearing capacity of existing prestressed concrete V.S simply and quickly, and also improve accuracy of cxperimental results and working efficiency. 展开更多
关键词 prestressed concrete v.s DEAD load TEST FAST TEST
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Influences of Installment Tensioning Technology on Bearing Capacity of Rectangular Prestressed Concrete Beam
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作者 Hongyan Ding Peng Liu +2 位作者 Puyang Zhang Yan Zhu Yaohua Guo 《Transactions of Tianjin University》 EI CAS 2017年第2期122-129,共8页
To obtain the relationship between use of installment tensioning technology and the bearing capacity of prestressed concrete beams, tensile and cyclic loading tests are conducted on five rectangular prestressed concre... To obtain the relationship between use of installment tensioning technology and the bearing capacity of prestressed concrete beams, tensile and cyclic loading tests are conducted on five rectangular prestressed concreted specimens. Two types of prestressed tensioning methods are adopted in the tests, one uses installment tensioning technology to tension beams on days 4, 12, and 8, 12, respectively, and the other adopts the conventional method to tension the beam on day 28 only. The age of concrete, number of times tensioned, and the prestress value of early tensioning are considered in tests. Results show that use of installment tensioning technology has no effect on the bending failure pattern of prestressed concrete beams, but it reduces prestress loss and increases crack and yield loads. © 2017, Tianjin University and Springer-Verlag Berlin Heidelberg. 展开更多
关键词 Bearing capacity concreteS Cyclic loads prestressed beams and girders prestressed concrete
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