Journal articles: 'Prestressed concrete structure'

1

Wei, Fang Fang, Jin Bo Wang, Ben Wei Zou, and Hao Sun. "FEM Research on Static Mechanical Performance of Twice Prestressed Composite Curved Beam." Advanced Materials Research 243-249 (May 2011): 1038–42. http://dx.doi.org/10.4028/www.scientific.net/amr.243-249.1038.

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The conception of twice prestressed composite structures (TPCS) was proposed in order to solve great distortion problems in prestressed concrete structures. Through decomposition of the total prestress, we define the 1st stage as one part of the prestress acting on a prefabricated beam, and the 2nd as the other part on a post-pouring structure. This kind of structure could substantially decrease its distortion and enhance the efficiency of prestress, at the same time contributing to flexibly laying the prefabricated concrete. A continuous curved prestressed concrete box girder bridge was modeled with the FEM software ANSYS, taking into account the ordinary steel and prestressed losses. The aim is to analyze the deformation, stress performance, the impacts of the primary prestressed force value on the anti-deforming performance as well as bearing load performance of the twice prestressed composite curved beam. The conclusion could provide a basis for the application and promotion of the structure.

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An, Jing Bo. "Unified Design of Tensile-Compression Prestressed Concrete Structure." Applied Mechanics and Materials 193-194 (August 2012): 970–75. http://dx.doi.org/10.4028/www.scientific.net/amm.193-194.970.

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Structural characteristics of tensile-compression prestressed concrete are introduced briefly in this paper. Firstly, with current concrete structure design code（GB50010）, requirements for materials used in tensile-compression prestressed concrete structure are put forward; and for prepressing stress steel pipe, strength value and basic types for structure design are determined. Secondly the calculation method of prestress loss is given during each work stage of tensile-compression prestressed concrete; and the basic measures of cracking control are concluded. Thirdly, bearing capacity formula of tensile-compression prestressed concrete structure and stress checking formula of menbers in construction stage are provided. Finally structure design of tensile-compression prestressed concrete is unified

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Zhang, Shan, Kai Yin Zhang, Bing Yang Xie, and Zhong Lin Fan. "Research on the Mechanism of Prestressed Loss for Curving Hole of Prestressed Concrete Structure Caused by Frictional Resistance." Applied Mechanics and Materials 351-352 (August 2013): 156–63. http://dx.doi.org/10.4028/www.scientific.net/amm.351-352.156.

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Excessive prestress loss in Prestressed Concrete (PC for short) continuous beam bridges and continuous rigid frame bridges cause structures to be different types of diseases. Based on theoretical analysis and experiment , this paper points out the imperfection of the effective prestress formula in Curving Hole at present. According to the research on the influencing factor of prestressed loss in Curving Hole of friction coefficient, it plays a remarkable role on the analysis about the prestressed loss in Curving Hole of prestressed concrete structure.

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Wang, Yongguang. "Determination of Bridge Prestress Loss under Fatigue Load Based on PSO-BP Neural Network." Computational Intelligence and Neuroscience 2021 (July 12, 2021): 1–10. http://dx.doi.org/10.1155/2021/4520571.

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During the service period of a prestressed concrete bridge, as the number of cyclic loads increases, cumulative fatigue damage and prestress loss will occur inside the structure, which will affect the safety, durability, and service life of the structure. Based on this, this paper studies the loss of bridge prestress under fatigue load. First, the relationship between the prestress loss of the prestressed tendons and the residual deflection of the test beam is analyzed. Based on the test results and the main influencing factors of fatigue and creep, a concrete fatigue and creep calculation model is proposed; then, based on the static cracking check calculation method and POS-BP neural network algorithm, a prestressed concrete beam fatigue cracking check model under repeated loads is proposed. Finally, the mechanical performance of the prestressed concrete beam after fatigue loading is analyzed, and the influence of the fatigue load on the bearing capacity of the prestressed concrete beam is explored. The results show that the bridge prestress loss characterization model based on the POS-BP neural network algorithm has the advantages of high calculation efficiency and strong applicability.

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Li, Chen, Kai Yin Zhang, and Zhong Lin Fan. "Research on Prestressed Loss in Curving Hole of Prestressed Concrete Structure Caused by Frictional Resistance." Applied Mechanics and Materials 587-589 (July 2014): 1668–71. http://dx.doi.org/10.4028/www.scientific.net/amm.587-589.1668.

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Excessive prestressed loss in prestressed concrete continuous beam bridge and continuous rigid frame bridge causes structures appearing different types of diseases. By theoretical analysis on computational expression of effective prestress in curving hole, and distribution of contact stress and experiment about prestressed loss caused by frictional resistance, this paper points out the disadvantages of current effective prestress formula in curving hole. According to the research on the major influencing factors of prestressed loss in curving hole-contact status and friction coefficient μ, it plays a remarkable role on the further analysis of prestressed loss in curving hole.

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Xie, Xin Ying, and Xin Sheng Yin. "The Application of Stability on Prestressed Concrete Cable-Beam Structure System." Applied Mechanics and Materials 256-259 (December 2012): 930–33. http://dx.doi.org/10.4028/www.scientific.net/amm.256-259.930.

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The paper introduces the importance of stability and current reseach status on prestressed concrete cable-beam structure system.It demonstrates the basic relative theory on stability in concretely research and applies this theory into the prestressed concrete cable-beam structure system,the formula of stability on this system is come true to make the analyze prestressed concrete cable-beam structure system precisely.

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Li, Chang Chun, and Li Yun Yi. "On Detection Technologies of Pre-Stressed Duct Grouting Fullness." Advanced Materials Research 933 (May 2014): 71–75. http://dx.doi.org/10.4028/www.scientific.net/amr.933.71.

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Aging and deterioration (such as weakening of concrete strength and loss of prestress) of various degree will inevitably happen to prestressed concrete beam in service. In making the prestressed concrete beam, it is of vital importance to ensure that the prestress tension is sufficient, duct grouting is compact enough and concrete pouring is in good quality. Otherwise, structure will deteriorate faster and safety hazard and even bridge collapse may ensue, causing considerable economic losses.

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Guo, Er Wei, Ying Xin Qian, Gang Xu, Jin Dong Gao, and Chen Guang Li. "The Application of Building Information Model in the Deepen Design of Prestressed Concrete Structures." Applied Mechanics and Materials 716-717 (December 2014): 303–6. http://dx.doi.org/10.4028/www.scientific.net/amm.716-717.303.

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Currently deepen design of prestressed concrete structure exists various problems, them can be solved using BIM building digital technology in the deepen design phase of prestressed concrete structures, such as constant correction of the two-dimensional drawings. BIM technology was advanced technology, the design of prestressed concrete structures, was given by using BIM technology in the complete process; Design process and value of the application of the BIM technology in the prestressed concrete structure were analyzed, Prospects of the BIM technology using in prestressed concrete were discussed.

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9

Chen, Feng, Shuan Hai He, Da Lin Hu, and Bing Yuan Huang. "Anti-Shear Reliability Analysis of Existing Pretension Prestressed Concrete Beam Bridges in the Corrosion Environment with Acid Rain." Advanced Materials Research 150-151 (October 2010): 1488–94. http://dx.doi.org/10.4028/www.scientific.net/amr.150-151.1488.

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Under the acid rain corrosion condition, the shear-bearing capacity of the pretension prestressed concrete beam will attenuate gradually with the stirrup corrosion and concrete deteriorate. Moreover, the stress corrosion cracking failure and the bond force degradation of the prestressed wires that caused by the aggravated corrosion mediator ingress will further increase the shear failure risk of the pretension prestressed concrete structure without any symptom. The paper presents a shear bearing capacity calculation model of the pretension prestressed concrete beam bridge and discuss the time-variation model of the stirrup corrosion considering the effective prestress attenuation under the acid rain corrosion condition. The analysis method on anti-shear reliability of existing pretension prestressed concrete beam bridges under the sodium sulfate corrosion condition is proposed then. The method will be used in the durability and safety evaluation of the shear-bearing capacity of the existing pretension prestressed concrete beam bridges in the corrosion environment with acid rain.

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Zhang, Guanhua, Jiawei Wang, Jinliang Liu, Yanmin Jia, and Jigang Han. "Analysis of loss in flexural stiffness of in-service prestressed hollow plate beam." International Journal of Structural Integrity 10, no. 4 (August 12, 2019): 534–47. http://dx.doi.org/10.1108/ijsi-09-2018-0055.

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Purpose During service, cracks are caused in prestressed concrete beams owing to overload or other non-load factors. These cracks significantly affect the safety of bridge structures. The purpose of this paper is to carry out a non-linear iterative calculation for a section of a prestressed concrete beam and obtain the change in stiffness after the section cracks. Design/methodology/approach The existing stress of prestressed reinforcement was measured by performing a boring stress release test on two pieces of an in-service 16 m prestressed concrete hollow plate. Considering the non-linear effects of materials, the calculation model of the loss in the flexural stiffness of the prestressed concrete beam was established based on the existing prestress. The accuracy of the non-linear calculation method and the results obtained for the section were verified by conducting a bending destruction test on two pieces of the 16 m prestressed concrete hollow plate in the same batch and by utilising the measured strain and displacement data on the concrete at the top edge of the midspan section under all load levels. Findings The flexural stiffness of the section decreases rapidly at first and then gradually, and structural rigidity is sensitive to the initial cracking of the beam. The method for calculating the loss in the flexural stiffness of the section established with the existing stress of prestressed reinforcement as a parameter is accurate and feasible. It realizes the possibility of assessing the loss in the rigidity of a prestressed concrete structure by adopting the existing stress of prestressed reinforcement as a parameter. Originality/value A method for quickly determining the loss in the stiffness of structures using existing prestress is established. By employing this method, engineers can rapidly determine whether a bridge is dangerous or not without performing a loading test. Thus, this method not only ensures the safety of human life, but also reduces the cost of testing.

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11

Wang, Yu Zhuo, and Chuang Guo Fu. "Calculation of Ultimate Bearing Capacity of Prestressed Steel Reinforced Concrete Structure under Fire." Advanced Materials Research 250-253 (May 2011): 2857–60. http://dx.doi.org/10.4028/www.scientific.net/amr.250-253.2857.

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Prestressed steel reinforced concrete structure, compared with other concrete structure has its unique advantages. So it is mainly used in large span and conversion layers. With the popularization of this structure,more attention should be payed on fire resistance performance. On the basis of reasonable assume,two steps model is used as concrete high strength calculation model. Simplified intensity decreased curve is used as rebar,steel and prestressed. Two ultimate bearing capacity formulas of prestressed steel reinforced concrete beam are established. One is for the beam whose tensile area is under fire, the other is for the beam whose compression area is under fire. Prestressed steel reinforced concrete structure has both prestressed concrete structure’s advantages and steel reinforced concrete structure ’s advantage. Steel reinforced concrete is used to improve the bearing capacity of the structure. Prestressed steel is used to improve the ultimate state of structure’s performance during normal use. Thereby structure’s performance is better to play. There are many similarities between prestressed steel reinforced concrete structure and steel reinforced concrete structure about fire resistance performance. Because of prestressed steel reinforced concrete structure’s own characteristics, there are still many problems about fire resistance. This paper mainly presented bending terminal bearing capacity of prestressed steel reinforced concrete beam under fire. Established simplified formulae for calculation, it is meet the engineering accuracy requirement.

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12

Wen, Hua Bin, Yu Lin Zhan, and Hai Bo Liu. "A Nonlinear Study on the Prestressed Structure of High Strength Concrete - Steel Fiber Concrete." Advanced Materials Research 335-336 (September 2011): 743–51. http://dx.doi.org/10.4028/www.scientific.net/amr.335-336.743.

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In the construction of high-rise buildings, large span structures and tall structures, the combinatorial design structure of high strength concrete, steel fiber concrete, prestressed tendon and ordinary steel bar is a main measure to bring the advantages of high strength concrete into full play. This paper studies the nonlinear constitutive relations of high strength concrete, steel fiber concrete and steel bar. By using finite element method, this paper carries out a numerical simulation of the whole monotonic loading process of box prestressed continuous beam of high strength concrete - steel fiber concrete and gets comparatively detailedc calculating results, which provide a theoretical reference for the reasonable combinatorial design of high strength concrete,steel fiber concrete, prestressed tendon and ordinary steel bar.

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13

Kraľovanec, Jakub, František Bahleda, Jozef Prokop, Martin Moravčík, and Miroslav Neslušan. "Verification of Actual Prestressing in Existing Pre-Tensioned Members." Applied Sciences 11, no. 13 (June 27, 2021): 5971. http://dx.doi.org/10.3390/app11135971.

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In the case of prestressed concrete structures, information about the actual state of prestressing is an important basis for determining their load-carrying capacity as well as remaining service life. During the service life of the prestressed concrete structure, the initial level of prestressing is inevitably reduced as a result of the actions of various factors. These reductions of prestressing force are considered as prestress losses, which are influenced by construction stages, used materials, prestressing technology, or required length of service life. Available standards enable the determination of the expected values of prestress losses. Ultimately, their calculation is part of the design procedure of every prestressed concrete structure. However, aging and often neglected infrastructure in Europe is also exposed to factors, such as environmental distress, that are not considered in standard calculations. Therefore, verified and reliable methods for determining the actual state of prestressing are needed. This paper presents an experimental program of an indirect method for the evaluation of the value of prestressing force in seven prestressed concrete sleepers. Particularly, the non-destructive saw-cut method as a pivotal object of this study is performed and assessed. Furthermore, the Barkhausen noise technique is used as a comparative method. Subsequently, the experimental campaign is supported by the numerical analysis performed in the ATENA 3D software. Finally, the experimentally determined values of residual prestressing force are compared to the expected level of prestressing according to Eurocodes.

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14

Hou, Wen Yu, Lian Guang Wang, and Peng Liu. "Bending Capacity of T Beam with Prestressed Concrete-Filled Steel Tube." Applied Mechanics and Materials 368-370 (August 2013): 1048–51. http://dx.doi.org/10.4028/www.scientific.net/amm.368-370.1048.

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The prestressed composite T beam with concrete-filled steel tube is made through welding with half I-beam to connect the concrete-filled circular steel tube. The prestressed reinforcement was equipped on the T-beam. The load-bearing capacity and rigidity of the composite beam was enhanced by using prestressed force. In consideration of applying prestress, the corresponding parts stress and strain from the beginning of applying prestress to the phase of elimination of the pressure is calculated through the process of applying prestress; establish the equation of elastic flexural capacity with different location of neutral axis according to the theoretical analyses. Also use the superposition method to build the equation of the deflection. The computational results show that applying prestress reduces the deformation of the composite structure and the mechanic performance has improved which provide important theoretical basis with practical application in engineering.

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15

Chen, Feng, Da Lin Hu, and Yi Li Sun. "Anti-Shear Reliability Analysis of Existing Pre-Tensioned Prestressed Concrete Beam Bridges under Atmosphere Condition." Advanced Materials Research 255-260 (May 2011): 1017–22. http://dx.doi.org/10.4028/www.scientific.net/amr.255-260.1017.

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The shear bearing capacity of pretensioning prestressed concrete beam bridge mainly depends on the stirrup and concrete of the beam, but the longitudinal pre-pressure plays a certain role for the shear bearing of the structure. Under the carbonization corrosion condition, the shear-bearing capacity of the pretensioning prestressed concrete beam will attenuate gradually with the stirrup corrosion and concrete deteriorate. And the risk of brittle shear failure will be increased with the enhanced reinforcement corrosion amount. The paper presents an anti-shear calculation model of the pretensioning prestressed concrete beam bridge, and discusses the time-variation model of the corrosion stirrup considering the effective prestress attenuation under the carbonization corrosion condition. The analysis method on the anti-shear reliability of existing pretensioning bridges under the corrosion condition is proposed then. The method will be used in the durability and safety evaluation of the shear-bearing capacity of the existing pretensioning prestressed concrete bridges.

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Yan, Xueyuan, Suguo Wang, Canling Huang, Ai Qi, and Chao Hong. "Experimental Study of a New Precast Prestressed Concrete Joint." Applied Sciences 8, no. 10 (October 10, 2018): 1871. http://dx.doi.org/10.3390/app8101871.

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Precast monolithic structures are increasingly applied in construction. Such a structure has a performance somewhere between that of a pure precast structure and that of a cast-in-place structure. A precast concrete frame structure is one of the most common prefabricated structural systems. The post-pouring joint is important for controlling the seismic performance of the entire precast monolithic frame structure. This paper investigated the joints of a precast prestressed concrete frame structure. A reversed cyclic loading test was carried out on two precast prestressed concrete beam–column joints that were fabricated with two different concrete strengths in the keyway area. This testing was also performed on a cast-in-place reinforced concrete joint for comparison. The phenomena such as joint crack development, yielding, and ultimate damage were observed, and the seismic performance of the proposed precast prestressed concrete joint was determined. The results showed that the precast prestressed concrete joint and the cast-in-place joint had a similar failure mode. The stiffness, bearing capacity, ductility, and energy dissipation were comparable. The hysteresis curves were full and showed that the joints had good energy dissipation. The presence of prestressing tendons limited the development of cracks in the precast beams. The concrete strength of the keyway area had little effect on the seismic performance of the precast prestressed concrete joints. The precast prestressed concrete joints had a seismic performance that was comparable to the equivalent monolithic system.

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Han, Jian Qiang, Zhen Bao Li, and Xiao Sheng Song. "Research on Seismic Performance of Prestressed Precast Reinforced Concrete Intelligent Structure." Applied Mechanics and Materials 50-51 (February 2011): 1003–7. http://dx.doi.org/10.4028/www.scientific.net/amm.50-51.1003.

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This thesis studies deeply the crack development characteristics, failure pattern, hysteresis curve and the displacement ductility of this new prestressed precast reinforced concrete intelligent structure, by analyzing one prestressed precast reinforced concrete frame under low reversed cyclic load test. Prestressed precast reinforced concrete frame is a new assembly architecture intelligent structure. We build a model using finite element analysis software to the test piece model analysis, the analysis result agree well with the experimental results. Experimental studies indicate that this new prestressed precast reinforced concrete intelligent structure has a good seismic performance. This prestressed precast reinforced concrete frame is a new kind of structural system complying with the development of architectural industrialization, which is worthy of popularization and application in the earthquake area.

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Eratodi, I. Gusti Lanang Bagus, Ali Awaludin, Ay Lie Han, and Andreas Triwiyono. "Evaluation and Study of Prestressed Slab Structure Precast Modular Concrete." MEDIA KOMUNIKASI TEKNIK SIPIL 26, no. 1 (July 30, 2020): 44–51. http://dx.doi.org/10.14710/mkts.v26i1.27765.

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Prestressed precast modular concrete slabs function rigid pavement, supporting vehicle loads above it on subgrade with relatively low bearing capacity. This slab measures 2000 x 850 x 150 mm3 of regular reinforced concrete (old production) or prestressed concrete (new production) quality K-500. After several times of use, damage occurs mainly at the end of the slab in the form of spalling. The objectives of the study and evaluation were: (1) observing damage; (2) material quality data; (3) numerical modeling by taking into account material properties, loading and soil conditions; and (4) providing slab design recommendations including materials and geometrics. The method of study and evaluation of slab damage was done by observing the damage, taking concrete core-case and testing it in the laboratory, and modeling the slab structure with various parameters (soil data, concrete quality and slab geometry). Field observations and analysis results show that concrete slab spalling occurs initially at the edge (850 mm wide) which in turn causes the effectiveness of the pre-tension force to be suboptimal and finally the concrete spalling volume increases. Apart from the frequency of collisions during installation and slab deformation when supporting vehicle loads. Concrete spalling problems also due to inappropriate concrete quality.

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Chen, Feng, Yi Li Sun, and Da Lin Hu. "Prestressed Concrete Covering Layer System Depth Zonation in Marine Environment." Advanced Materials Research 250-253 (May 2011): 2337–41. http://dx.doi.org/10.4028/www.scientific.net/amr.250-253.2337.

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The chloride ingress of prestressed concrete should consider much more factors than common reinforced concrete. And the prestressed concrete covering layer system is a complex system which includes not only the non-uniform layer of concrete, but also the non-prestressed reinforcement, the metal corrugated pipe and the cement paste incrustation body in the pipe. Taking into consideration of the effect of stress level in concrete and the non-prestressed reinforcement, the multi-factors for chloride ingress corrosion model is achieved and the durability limit state equation for prestressed concrete structures is established. The paper presents a determination method for the depth of the covering layer system of prestressed concrete structure in marine environment. The principle for zonation of the prestressed concrete covering layer system’s minimum depth is established after sensitivity analysis of the effect factors in the marine environment, and the environment temperature and humidity are identified as the main environment sensitivity factors for the depth. Therefore, the paper also proposes zoning method and the division regions for the prestressed concrete covering layer system depth of the coastal region in China.

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Xie, Xin Ying, and Xin Sheng Yin. "The Application of Cable's Arrangement and Stability on Prestressed Cable-Beam Structure." Applied Mechanics and Materials 405-408 (September 2013): 1096–99. http://dx.doi.org/10.4028/www.scientific.net/amm.405-408.1096.

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The paper analyzes the basic theory of prestressed concrete cable-beam structure in single span and single direction.The paper arranges reasonably the shape of cable,deduces the equation of cable. It introduces the reseach status and the importance of stability and demonstrates the basic relative theory on stability in concretely research and applies this theory on prestressed concrete cable-beam structure. It has significant prospect and is easy to put into practice .

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NISHIYAMA, Minehiro, Masahiko KANGAWA, Shoji SHIRAHAMA, Kennichi NAKAMURA, and Yuichi SATO. "JSMS Committee on Prestressed Concrete Structure." Journal of the Society of Materials Science, Japan 64, no. 7 (2015): 607. http://dx.doi.org/10.2472/jsms.64.607.

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Ji, Jing, Dan Yang, Zhen Chao Teng, and Hong Guo Ren. "Structure Design and Comparison Analysis of Frame System with Angle-Steel Column and Prestressed Beam." Applied Mechanics and Materials 182-183 (June 2012): 1626–29. http://dx.doi.org/10.4028/www.scientific.net/amm.182-183.1626.

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In combination with structure design of the JuLang farm activity center, a new frame structure which consists of angle-steel concrete composite column and prestressed concrete beam is adopted. Three kinds of schemes and the concrete design process are given, those are the well beam-shape structure, prestressed girder floor structure and prestressed beam and slab structure. Clear height indoor, material costs and time limit of three kinds of schemes are analyzed comparatively, the reason selecting prestressed girder structure system is given, these can provide reference for scheme selection and design of similar engineering.

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Ren, Zhen. "Study on Structure Analysis of Prestressed Reinforced Concrete Inverted Siphon." Applied Mechanics and Materials 488-489 (January 2014): 585–88. http://dx.doi.org/10.4028/www.scientific.net/amm.488-489.585.

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This paper adopt universal finite element calculation software to carry out force analysis for Shayubeigou prestressed reinforced concrete inverted siphon,computer is applied in analysis of prestressed reinforced concrete inverted siphon. Deducing variation law of the inverted siphons stress and displacement in construction process and operating process. The calculation results further shown design schemes rationality and safety. which provide reliable reference of design and construction for the prestressed reinforced concrete inverted siphon.

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Balevičius, Robertas, and Eugedijus Dulinskas. "EVALUATION OF CONCRETE LINEAR CREEP IN DETERMINATION OF STRESS STATE AND STEEL PRESTRESS LOSSES IN CONCRETE MEMBERS/BETONO TIESINIO VALKŠNUMO ĮVERTINIMAS, NUSTATANT GELŽBETONINIŲ ELEMENTŲ ĮTEMPIMŲ BŪVĮ IR ARMATŪROS IŠANKSTINIO ĮTEMPIMO NUOSTOLIUS." JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT 5, no. 6 (December 31, 1999): 364–73. http://dx.doi.org/10.3846/13921525.1999.10531491.

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Determination of stress-strain state imposed by concrete linear creep and specification of steel prestress losses in linear prestressed concrete member is discussed in this article. Particularities of regulations of the Code acting in Lithuania [1] and of Eurocode [2] are analysed and a modified method for calculation of steel prestress losses due to concrete linear creep in prestressed concrete linear members suitable for assessment of Code regulations is presented. Also, the method is used for analysis of results of long-term tests of reinforced concrete members. In Lithuania, a code based on investigations of prestressed concrete members is used for calculation of steel prestress losses due to concrete creep. Therefore calculation of losses is associated with stress-strain state of the member in time t in empirical way only and time dependent stress-strain state is adjusted by additional coefficients to take into consideration concrete creep. Analogous calculations of steel prestress losses by Eurocode are presented in a more general form and are based on creep theory. It is clear that in the first [1] and the second [2] cases the same change in stress-state is evaluated by different parameters. Therefore it is important to create a general method based on concrete creep characteristics. General case of eccentrically reinforced prestressed concrete linear member under the action of prestressing forces changing with time in relation to prestress losses due to concrete creep is analysed (Fig 1). Stress-strain time dependent state of such member with the changing concrete stress σ b (t) and σ′ b (t) is determined using well-known equations of equilibrium (1–4) and integral differential equations (7–8) for evaluation of concrete creep deformations [4–8]. These equations are solved by numerical method (9–10) dividing time period considered in intervals. In reference [9] a more particular solution method evaluating variation of interval magnitude in relation to accuracy of solution is presented. In such a way it is possible to assess reduction of concrete stress (13–14) at time moment t when loss of steel prestress due to concrete creep takes place (33–34). There are many experiments performed for investigating concrete creep and determinating time dependent stress-strain state of reinforced concrete members. Various methods are applied for analysis of these data. Assumptions of these methods influence the conclusions of the analysis. In this article there is presented a general method giving opportunity to assess creep of concrete members by the same characteristics, when specific creep (51) or coefficient of creep (52) is determined by tests on eccentrically prestressed linear members (the case of axially prestressed members is presented in [9]). Pure specific creep C* (t,t 0) values determined according to the method proposed in this article and results of experimental investigations [12] of prestress in steel of eccentrically prestressed concrete members and also according to data of analysis [11] of the Code [1] are presented in Fig 2. Using the same creep characteristics method of the Code EC-2 and proposed in this article losses of prestress in steel due to concrete creep were calculated according to EC-2 and the method proposed. Values of these losses and their ratio are presented in Fig 3 and 4. In Fig 5, losses of prestress in steel due to creep predicted after 70 years were calculated in accordance with data of the Code SNiP [1] analysis [11] and regulations of the Code EC-2 [2]. Relationships (62) including (63), (64) formulas are modified EC-2 method for regulation of steel prestress loss due to concrete creep calculation for doubly reinforced members are proposed in the article. Results of analysis of regulations of Eurocode EC-2 and the Code SNiP indicate that design according to Code [2] method for steel prestress loss due concrete creep calculation in all cases gives increased values of stiffness and crack resistance characteristics of the structure, but larger amount of steel is to be used in comparison with the design according to SNiP [1].

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Cai, Hua, Feng Shuo Li, and Xin Li. "Analysis of Concrete Pavements Characteristics of Oblique Distribution Forms of Prestressed Reinforcement." Applied Mechanics and Materials 97-98 (September 2011): 316–20. http://dx.doi.org/10.4028/www.scientific.net/amm.97-98.316.

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ABAQUS software is adopted. And the three-dimensional finite element models, respectively oblique and vertical reinforcements, are used for the calculation of the prestressed concrete pavement structure. The prestress is imposed on pavement by changing the temperature of reinforcements. Then through the analysis of mechanical behavior of the two kinds of prestressed reinforcement concrete pavements under the standard load. The results show that the oblique reinforcement pavement is flatter and the range of influnence is smaller. These data of the two kinds of pavements are provided for engineering design and construction.

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Abdel-Jaber, Hiba, and Branko Glisic. "Monitoring of long-term prestress losses in prestressed concrete structures using fiber optic sensors." Structural Health Monitoring 18, no. 1 (January 29, 2018): 254–69. http://dx.doi.org/10.1177/1475921717751870.

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This study presents a method for on-site assessment of prestress losses in prestressed concrete structures. The study is motivated by the increased use of prestressed concrete, the importance of prestressing force levels as a parameter, and the lack of formalized methods for its on-site assessment. The proposed method uses strain measurements from long-gauge fiber optic sensors to study strain changes at the centroid of stiffness (i.e. centroid of composite section) of the cross-sections. Its advantages include (1) robustness to operational load on the structure caused by seasonal and daily temperature variations, in addition to loading; (2) rigorous quantification of uncertainties associated with measurements and parameters; and (3) applicability to a wide range of beam-like structures. The application of the method is illustrated through application to measurements collected over a 7-year period from strain sensors embedded in Streicker Bridge, a post-tensioned concrete pedestrian bridge on the Princeton University campus. Application of the method indicates that prestress losses measured by sensors are of comparable magnitude to design estimates, which implies that estimates are not necessarily overly conservative.

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Zhao, Jun, and Di Tao Niu. "Study on Corroded Detection of Bridge Prestressed Reinforcement Based on the Magnetic Flux Leakage Method." Applied Mechanics and Materials 105-107 (September 2011): 1241–44. http://dx.doi.org/10.4028/www.scientific.net/amm.105-107.1241.

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As the pretressed reinforcement of prestressed concrete structure leads to rust, it would bring serious disadvantage effect to load capacity of the concrete members and reduce the reliability of all concrete structure greatly more than that of ordinary steel caused. If the prestressed reinforcement can be detected in time, the prestressed concrete structure would be got effective maintenance. In the paper, magnetic leakage testing method used in ordinary steel detection is applied to test the simulation corrosion bug of the prestressed reinforcement in bridge with nondestructive mode. The result of experiment indicates that in the distance of 100 mm from the concrete surface the magnetic leakage testing method can detect effectively the loss ratio of cross-section more than 20 percent of a hank of prestressed strands caused by a part of prestressed strands corroded to break. At last, the paper also puts forward the experiment problems in existence and the improvement methods.

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Zeng, Qing Xiang, and Da Jian Han. "Selection of Concrete Creep Analytical Models for Modern Prestressed Bridges." Applied Mechanics and Materials 90-93 (September 2011): 1023–26. http://dx.doi.org/10.4028/www.scientific.net/amm.90-93.1023.

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The modern prestressed concrete bridges have the characteristics of large-span, high concrete strength, reinforced volume prestress and linear shape complexity. The structure bearing capacity and durability are considerable impacted by concrete creep, such as stresses redistribution and deflections increase. Some of the prediction concrete creep models that are being widely used at present are briefly introduced in this paper. Based on the analysis of existing research achievement, for the aim of improving the calculation accuracy of creep effects in bridge structures, several main problems that should be paid attention to in concrete creep analysis are pointed out from four aspects: (1) in design stage, the reasonable creep prediction model should be selected in accord with the local building materials and environment conditions; (2) during the analysis of creep effects, the initial stresses state and the stresses redistribution should be attended; (3) the reliability of prestress loss calculation should be considered in analysis of concrete creep effects; (4) the differences between normal construction materials and that of new types should be taken into account in concrete creep analysis.

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Küsel, Frank, Elsabe Kearsley, Liam J. Butler, Sarah A. Skorpen, and M. Z. E. B. Elshafie. "Measured temperature effects during the construction of a prestressed precast concrete bridge beam." MATEC Web of Conferences 199 (2018): 11013. http://dx.doi.org/10.1051/matecconf/201819911013.

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Prestress losses in precast concrete beams include the short-term effects of elastic shortening and the long-term effects of concrete shrinkage, concrete creep and steel relaxation. Temperature effects are, however, excluded. The aim of this research was to monitor the behaviour of a prestressed precast concrete bridge beam, focussing on temperature effects and destressing. Successful monitoring assists in comparing the real performance of a structure to the expected design performance, and in managing the durability of the monitored structure. The effect of temperature variation on strains in prestressed beams was investigated by instrumenting a precast beam. Temperature and strains were monitored from the day of casting up to and including the cutting of the pretensioning strands. Daily temperature variations causing vertical non-linear temperature profiles resulted in internal strains of up to 28 % of the strains caused by destressing. It was therefore concluded that thermal effects before destressing resulting from elevated curing temperatures and daily temperature changes should be considered in the calculation of prestress losses. The monitoring techniques used were successful in determining the stresses and strains within the beam, which can be used to compare real prestress losses with the losses assumed in design.

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Ren, Zhenhua, Xiantao Zeng, and Junbo Sun. "Using Two-Way Prestressed Semicircular Steel Plate for Construction of Reinforced Concrete Cylinder Column." Complexity 2018 (July 30, 2018): 1–10. http://dx.doi.org/10.1155/2018/1481837.

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A concrete column has a significant influence on constructions because the component withstands the major weight of the whole structure. However, the ordinary concrete column has limited capacity to resist to multiaxial loadings. Since steel plate is one of the most common materials used in construction, concrete reinforced with steel plates based on prestressing reinforcement technology would be a directly applicable solution to the enhancement of mechanical property. In this study, a new reinforcement method upon concrete cylinder column used a two-way prestressed semicircular steel plate, which has already been patented. The study firstly analyzed the stress-bearing situation of the short concrete column reinforced by a two-way prestressed semicircular steel plate. The considerable substitution effect of vertical prestressing force on the concrete column was explored. The multiple restriction effects of horizontal prestressing force, semicircular steel plate, and stirrup were examined. Thereby, the calculation model was derived for the prestressed structure. Secondly, the formula was verified by experiments with close agreements. The result indicated that a unified strength theory was applicable to the theoretical calculation for short concrete column reinforced with a prestressed semicircular steel plate under axial compression, providing the foundation for analytical computation of prestressed semicircular steel plate-reinforced concrete column structures.

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Su, Jian, Nan Gai Yi, Zong Guang Sun, Yang Bai, and Ai Guo Zhang. "Experimental Study on Mechanical Performance of Unbonded and Bonded Prestressed Concrete Beams." Applied Mechanics and Materials 178-181 (May 2012): 2387–92. http://dx.doi.org/10.4028/www.scientific.net/amm.178-181.2387.

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The experiment which based on the stress performance of unbonded and bonded prestressed concrete beam, has made a systematically research on the stress and strain variation law of pretressing tendon in the aforementioned reinforcement prestressed concrete structure. When the bonded prestressed concrete beam bearing load, there is a larger variation in stress and strain of prestressing reinforcement along the length. The maxima of stress and strain of prestressing reinforcement in bonded prestressed concrete beam appears in midspan, it is achieved the yield stress and yield strain, the minima appears in bearing, the stress and strain of prestressing reinforcement in bonded prestressed concrete beam is proportional to the distortion. The stress and strain of prestressed reinforcement in unbonded prestressed concrete beam is almost the same along the length.

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32

Pandey, M. D., and M. A. Nessim. "Reliability-based inspection of post-tensioned concrete slabs." Canadian Journal of Civil Engineering 23, no. 1 (February 1, 1996): 242–49. http://dx.doi.org/10.1139/l96-025.

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In unbonded, post-tensioned prestressed concrete slabs and beams, corrosion of prestressed tendons due to moisture ingress and their subsequent breakage has been identified as a major problem raising serious concern over the safety of aged structures. The paper presents a practical Bayesian approach to reliability assessment of such structures based on the inspection of a randomly selected sample of prestressing tendons. To minimize inspection costs, clear guidelines are presented for selecting the minimum sample size necessary to demonstrate that the annual probability of failure of an existing structure is below the target value of 10−5, implied in the Canadian Standards Association concrete design code CAN3-A23.3-M84. A systematic and cost-effective incremental strategy is developed for inspection of existing prestressed concrete structures. Key words: reliability, Bayes theorem, prestressed concrete, unbonded post-tensioned system, inspection, corrosion, probability distribution, CSA Standard CAN3-A23.3-M84, slab.

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Xie, Xin Ying, and Xin Sheng Yin. "Research on Prestressed Concrete Cable-Beam Structure System." Applied Mechanics and Materials 226-228 (November 2012): 1145–48. http://dx.doi.org/10.4028/www.scientific.net/amm.226-228.1145.

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The article presents the method of research, introduces the relative theory, researches the force statement of prestressed concrete cable-beam structure system by the method of model test. The results of test and theory is consistent. Prestressed concrete cable-beam structure systems has lots of advantages than ordinary reinforced concrete, such as high bearing capability, less cost, less weight, the longer span and shorter construction period. It is easy to put into practice and has significant prospect.

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Jiang, De Bao, and Xiao Jing Gu. "Test Research of Prestressed Concrete Beams with CFRP under Low Cyclic Loading." Advanced Materials Research 163-167 (December 2010): 3848–52. http://dx.doi.org/10.4028/www.scientific.net/amr.163-167.3848.

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Through testing it is obtained that force and the damage that 1 root structure of prestressed concrete beams strengthened and 3 different layers CFRP reinforced stickup prestressed concrete beams under cyclic loading. This test results show that CFRP reinforcement effect of prestressed concrete beams is obvious, and at the same time the cracking of prestressed concrete beam has also has certain reinforcement effect; But the CFRP reinforcement effect is proportional to the number of layers.

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35

Ai, Hui, Chuan Qing Zhang, Li Zhang, and Ju Tian. "Research on Bearing Capacity of Prestressed Concrete T-Beam at High Temperature in Fire." Advanced Materials Research 160-162 (November 2010): 1716–23. http://dx.doi.org/10.4028/www.scientific.net/amr.160-162.1716.

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The bearing capacity of bridge structure would decrease under high temperature in fire, and there is a risk of structural collapse when the bearing capacity decreased to a certain degree. The estimate of bearing capacity of concrete structure at high temperature in fire will directly influence the scheme of disaster relief. Recently, there are a few researches on evaluating the bearing capacity of concrete structure at high temperature in fire, even fewer on bearing capacity of prestressed structure. Surface temperature and temperature of internal specific position of prestressed concrete T-beam are put forward in this paper by making use of ISO 834 international standard heating curve and distribution rules of temperature field of ASCE. The degradation of mechanical properties of concrete, steel bar, steel strand and other materials at high temperature are worked out according to relationships between material mechanical properties and high temperature, and on this basis, the bearing capacity of 3 prestressed concrete T-beams are calculated and evaluated at high temperature in fire. The results show that after being under 3-hour's high temperature in fire, the bearing capacity in high temperature of prestressed concrete T-beam would decreased to it’s 25% in normal; the stronger the concrete is or the thinner the concrete cover is, the greater decrease of bearing capacity of prestressed concrete T-beam would be. Based on calculations and evaluations, a statistics regression equation of bearing capacity of prestressed concrete T-beam at high temperature in fire is obtained.

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36

Fang, Shu Tian, Ying Zhang, and Yuan Gao. "The Influence of Lateral Confinement in Prestressed Concrete Structure under the Effect of Pre-Applied Force." Advanced Materials Research 479-481 (February 2012): 1687–90. http://dx.doi.org/10.4028/www.scientific.net/amr.479-481.1687.

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The author analyzed the effect of lateral confinement under the pre-applied force in prestressed concrete structure and analyzed the influence of lateral confinement under the equivalent load of pre-applied force and rotation angle by the matrix deflection method in prestressed frame beam, at the same time the formula for the influence modulus of lateral confinement in prestressed concrete structure was proposed. Based on the analysis of practical projects, it’s indicated that the modulus of lateral restraint decreased with the increase of pre-applied force, and this kind of influence was small, and was the advantageous influence. Thereby provided basis for rational design of lateral confinement for prestressed concrete structure.

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NOGUCHI, Tsutomu. "Historical development of prestressed concrete railway structure." Doboku Gakkai Ronbunshu, no. 442 (1992): 9–14. http://dx.doi.org/10.2208/jscej.1992.442_9.

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WATANABE, Akira. "Historical development of prestressed concrete. Highway structure." Doboku Gakkai Ronbunshu, no. 451 (1992): 1–5. http://dx.doi.org/10.2208/jscej.1992.451_1.

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Zheng, Yuanxun, Lei Yang, Pan Guo, and Peibing Yang. "Fatigue Characteristics of Prestressed Concrete Beam under Freezing and Thawing Cycles." Advances in Civil Engineering 2020 (September 4, 2020): 1–11. http://dx.doi.org/10.1155/2020/8821132.

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In order to reveal the influence of freezing and thawing on fatigue properties of the prestressed concrete beam, a kind of novel freeze-thaw test method for large concrete structure components was proposed, and the freeze-thaw experiments and fatigue failure test of prestressed concrete hollow beams were performed in this paper. Firstly, the compressive strength and dynamic elastic modulus of standard specimens subjected to different numbers of freeze-thaw cycles (0, 50, 75, and 100) were determined. Then, the static and dynamic experiments were performed for prestressed concrete beams under different freeze-thaw cycles. Depending on the static failure test results, the fatigue load for the prestressed concrete beam model was carried out, the fatigue tests for prestressed concrete beam under freezing and thawing cycles were done, and the influence of fatigue loading times on dynamic and static characteristics of prestressed concrete beam was also studied. Finally, the relation between fatigue characteristics and numbers of freeze-thaw cycles was established, and the fatigue life prediction formulas of prestressed concrete beams under freeze-thaw cycles were developed. The research shows that the freezing and thawing cycles had obvious influence on fatigue life, and the freezing and thawing cycles should be taken into account for life prediction and quality evaluation of prestressed concrete beams.

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40

Yang, Yumin, and John J. Myers. "Prestress Loss Measurements in Missouri's First Fully Instrumented High-Performance Concrete Bridge." Transportation Research Record: Journal of the Transportation Research Board 1928, no. 1 (January 2005): 118–25. http://dx.doi.org/10.1177/0361198105192800113.

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Prestress losses have a direct impact on concrete stress development and deflection behavior of highway bridge members. A poor estimate of prestress losses can result in a structure in which allowable stresses are exceeded or camber and deflection behavior is poorly predicted, such that the serviceability of a structure may be adversely affected. This paper reports the prestress losses observed throughout fabrication, shipment, erection, and the first 2 years of service for the first high-performance superstructure concrete bridge in Missouri. The prestress losses investigated included prerelease losses, elastic shortening losses, relaxation losses, creep losses, and shrinkage losses. Results from the study were compared with eight commonly used loss estimate models for total prestress losses, including AASHTO and Prestressed Concrete Institute methods. Recommendations were proposed by the authors for the most appropriate methodology to use to predict prestress losses in high-strength concrete girders accurately.

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Yang, Jian, and Zhi Fang. "Behavior of Prestressed Ultra High Performance Concrete Beams." Key Engineering Materials 400-402 (October 2008): 385–90. http://dx.doi.org/10.4028/www.scientific.net/kem.400-402.385.

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An experimental program was formulated to investigate the characteristics of complete stress-strain curve of UHPC in uniaxial compression and flexural behaviors of prestressed UHPC beams. The particular focus was the influence of the partial prestress ratio and jacking stress on the flexural response of UHPC beams. The tests of beams demonstrated that the UHPC beams have an excellent behavior in load carrying capacity, crack distribution and deformability; their ultimate deflection can reach 1/34～1/42 of the span. Based on this investigation, theoretical correlations for the prediction structure response of UHPC beams are proposed.

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Li, Ming Hong, Yi Li Wang, Shang Min Zheng, and Shui Wan. "Research and Analysis of Shear Connector in Prestressed Concrete Box-Girder with Corrugated Steel Webs." Advanced Materials Research 639-640 (January 2013): 790–95. http://dx.doi.org/10.4028/www.scientific.net/amr.639-640.790.

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The prestressed concrete box-girder with corrugated steel webs is a new type of steel-concrete composite structure. It has some advantages comparing with traditional prestressed concrete structure. Shear connector is a decisive component with which steel and concrete can work together in steel-concrete composite structure. In this paper, the most commonly used forms of shear connector in prestressed concrete composite girder with corrugated steel webs are introduced. The method of design and calculation of shear connector is described. Furthermore, the engineering design case of shear connector in the 4th Nanjing Yangtze River Bridge North Terminal Chuhe Bridge is presented. The method can be taken as a reference to the design of shear connector in the same kind bridge.

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Yu, Jian Jun, and Lian Guang Wang. "Nonlinear Analysis of Prestressed Cold-Formed U-Shaped Steel and Concrete Composite Beams." Advanced Materials Research 594-597 (November 2012): 749–52. http://dx.doi.org/10.4028/www.scientific.net/amr.594-597.749.

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Cold-formed U-shaped steel and concrete composite beam is a kind of composite beam which the steel and the concrete are integrated by welding connections on the cold-formed U-shaped steel and then pouring concrete on the steel. Now, many experts and scholars have carried out many experimental research and theoretical analysis about it. But, prestressed Cold-formed U-shaped steel and concrete composite beams have not been studied. Based on the structure , the nonlinear analysis mode of prestressed cold-formed U-shaped steel and concrete composite beams is proposed, the calculating program is researched. The calculating results show that the bearing capacity of composite beam increases with the increments of thickness of steel plate and concrete strength, and the thickness of steel plate has a larger effect than the width of the flange plate of concrete, applying prestress can enhance the bearing capacity and flexural rigidity of the composite beam.

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Liu, Zhong Min, Xue Hua Liu, and Jing Ji. "Simulation Analysis of a Beam-Slab Floor Structure and Comparison on Project Economy." Applied Mechanics and Materials 193-194 (August 2012): 1311–14. http://dx.doi.org/10.4028/www.scientific.net/amm.193-194.1311.

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Combined with the specific project in this paper, the working principle of prestressed high-strength concrete beam and floor system arrangement are presented. The prestressed high-strength concrete beam is simulated using ANSYS finite element software, the bearing capacity, stiffness and deflection are checked and the results can meet the requirement. Finally the prestressed construction technology and engineering economy of a classroom floor structure are given. These can provide reference for rational design of similar floor system.

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Li, Pan Wu, and Zhen Xing Xue. "Prefabricated Box Girder Crack's Reason Analysis and Preventative Measures." Advanced Materials Research 255-260 (May 2011): 3543–47. http://dx.doi.org/10.4028/www.scientific.net/amr.255-260.3543.

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With its good spanning capacity and whole structural stress performance, the prestressed concrete box girder is widely used in modern large-span bridge structures. But, if the construction of box girder prefabricated control is inappropriate, cracks will appear easily, thereby the structure stability and durability will be greatly influenced. Through analysis of concrete box girder constituent materials, pouring temperature, construction process, and according to correlative concrete anti-cracking theories and analysis, there comes the prestressed concrete box girder crack preventative measures and repairing technic.

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Ma, Xin Wei, Sen Zeng, Chong Hai Dong, Zhi Yu, and Guan Qi Huang. "Design of Assembled Post-Tensioned Prestressed Reactive Powder Concrete Wind Turbine Tower." Advanced Materials Research 1055 (November 2014): 38–43. http://dx.doi.org/10.4028/www.scientific.net/amr.1055.38.

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This paper proposes a new type of assembled post-tensioned prestressed reactive powder concrete (RPC) turbine tower structure. It includes the structure design of 200kW wind turbine tower according to the specifications, calculation of loading combinations and internal force, checking calculation of bearing capacity, prestressed concrete design and calculation of reinforcement. Local stress applied on the structure is analyzed by the finite element software of ANSYS, and the calculation results show that the bearing capacity calculation of RPC tower satisfies the requirements, and it is economical comparing with the traditional steel structures.

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Yu, Dong Ming, Zhi Qin Liu, and Feng Guang Chen. "Analysis on the Design and Application of Prestressed Concrete Supporting Piles." Applied Mechanics and Materials 44-47 (December 2010): 173–76. http://dx.doi.org/10.4028/www.scientific.net/amm.44-47.173.

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The supporting piles of deep foundation pits are usually made in reinforced concrete materials and rarely in prestressed concrete materials. But prestressed concrete materials have higher stiffness and less deformation and are suitable for controlling displacements or settlements. So, in this paper a practical engineering project as an example, the prestressed concrete supporting piles of the deep foundation pit are calculated and designed. Then, the settlement and inclination of the building adjacent the foundation pit with the prestressed concrete piles are calculated in the numerical software, FLAC. The results calculated in FLAC are compared with the actual settlement and inclination of the adjacent building during the foundation pit is excavated. The comparison confirms the feasibility of the supporting structure. This is a useful trial on the design of the prestressed concrete supporting piles.

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Song, Manrong, Jiaxuan He, Yuan Liu, Hang Zhang, Chenjun Ge, Yadong Jin, Bingkang Liu, Shenjiang Huang, and Yan Liu. "Seismic Behavior of Three-Story Prestressed Fabricated Concrete Frame under Dynamic and Low Reversed Cyclic Loading." Advances in Civil Engineering 2018 (September 10, 2018): 1–10. http://dx.doi.org/10.1155/2018/7876908.

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Precast concrete structure is the building industrialization of the sure route. It can realize the construction process of low energy consumption and low emission and effectively meet the green development requirements of the construction industry. Based on prestressing technique, the connections of the precast concrete structure obtain prestress producing integrate joints and continuous frames, which improve the seismic safety and are applied widely in the earthquake area. To study seismic behavior of prestressed fabricated concrete frame structure, the experiments on the concrete frame under dynamic loading and low reversed cyclic loading were carried out. The single-span three-story prestressed fabricated concrete frame can accurately represent the load-carrying capability and the failure mechanism of multistory frame. Results of the study show that experimental specimens have good behaviors such as full hysteresis curves, proper displacement restoring capacity, and energy dissipation; the maximum interlayer drift ratio arrives 0.27% which has no damage to the frame in small earthquakes subjected to the 102 gal peak ground acceleration; the frame is repairable in moderate earthquakes when the maximal interlayer drift ratio arrives 0.73% subjected to the 204 gal peak ground acceleration; plastic hinges appeared at the ends of beam under low reversed cyclic loading firstly where the section curvature ductility factor ranges from 3.64 to 5.62; biaxial compression is acquired at beam-column joints with the help of column axial force and horizontal prestressing force; the beam fails before the column in the prestressed fabricated concrete frame at interlayer drift ratio between 1.56% and 2.56%.

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Han, Jian Qiang, Xiu Yan Fu, and Yu Min Zhang. "Carbon Fiber Cloth in Structural Engineering Application." Advanced Materials Research 160-162 (November 2010): 146–50. http://dx.doi.org/10.4028/www.scientific.net/amr.160-162.146.

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The frame beam end uses the carbon fiber cloth restraint, then uses the steel stranded wire assembly,which is a new assembly architecture structure. This thesis studies deeply the crack development characteristics, failure pattern, hysteresis curve and the displacement ductility of prestressed precast reinforced concrete frame, by analyzing one prestressed precast reinforced concrete frame under low reversed cyclic load test. We build a model using finite element analysis software to the test piece model analysis, the analysis result agree well with the experimental results. Experimental studies indicate that assembly of prestressed reinforced concrete frame structure has a good seismic performance. This prestressed precast reinforced concrete frame is a new kind of structural system complying with the development of architectural industrialization, which is worthy of popularization and application in the earthquake area.

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Yang, Ya Xun. "Analysis of Stress Measuring and Testing of Continuous Rigid Frame Bridge." Advanced Materials Research 346 (September 2011): 787–92. http://dx.doi.org/10.4028/www.scientific.net/amr.346.787.

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According to the structure and construction features of prestressed concrete continuous rigid frame bridge, with reference to the principle of vibrational chord strain gauge to concrete, the vibrational chord strain gauges to concrete are used in the construction control of prestressed concrete continuous rigid frame bridge. This paper introduces the measurement techniques and methods for stress and strain of main girder of the bridge, analyses some infection factors of stress measuring and testing, and presents the error analysis methods of stress measuring and testing and calculation methods of true stress of structure. The techniques and analysis methods prove to be quite effective through the applications and provide background data for constructing safely of prestressed concrete continuous rigid frame bridge.

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Journal articles on the topic 'Prestressed concrete structure'

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