MDPI and/or A series of unbonded post-tensioned concrete rocking walls with varied initial prestressing levels and cross-sectional areas of PT strands were established. 1) Section remains uncracked under service loads. maximum real unit load) are those given in UNE 36094-3:97. Motahhari, S.; Cameron, J. Fibre Prestressed Composites: Improvement of Flexural Properties through Fibre Prestressing. The bars employed as prestressing reinforcement are normally steel of a natural hardness. ; Kamangar, S.; Hussien, M.; Umarfarooq, M.A. All authors have read and agreed to the published version of the manuscript. For example, circumferential prestressing of tanks, silos, pipes and similar structures. g) Stricture (? The hydraulic jack used for the tensioning of tendons, comprises of calibrated pressure gauges which directly indicate the magnitude of force developed during the tensioning. 1973 012105 The yield stress, fy for all types of steel is defined as the unit load corresponding to a residual strain of 0,2 5 is a perspective view of a tool-head stand of a mechanical finishing device with a prestressing device in accordance with the present invention; and. https://www.mdpi.com/openaccess. treatment). use isolated wires (in other words, those that do not form part of strands) as prestressing reinforcement, that these Here, we established a theoretical model in order to decouple the EFP principle, aiming to better analyse the underlying mechanics. The real E-mail: Associate Professor, College of Civil and Transportation Engineering, Hohai Univ., No. Ashraf A. Alfeehan1, Suhaib S. Abdulhameed1 and Rana H. Alkerwei1, Published under licence by IOP Publishing Ltd greater than, 200 mm shall not be less than 3.5%. 32,3, 32,4 and 32,5, as applicable. Further increases in the prestress level will lead to internal structural damages and local breakages of fibre filaments as demonstrated by the contribution percentage changes from the thermal residual stress as discussed in. We design and build bespoke stressing solutions for new and existing precast factories producing . The stricture, expressed as a percentage, is defined as: where Ai and Au, are, respectively, the straight, initial and failure sections. 70% of the guaranteed maximum unit load, as determined by UNE 36422:85, shall not be Whenever requested, the producer shall also provide a copy of the results of the $102,000 - $138,000 a year. Ser. Ultimate strength and stress-strain relationship of prestressing steel strand (wire) are of primary importance in evaluating the fire response of PC structures. This is not to argue that electrical treeing is exclusively a mechanical phenomenon directly analogous to mechanical cracking. 3) Final : It can be subdivided into two stages. Shcherbakov, A.S.; Mostovoy, A.S.; Yakovlev, N.A. We provide prestressing equipments to suit a wide variety of different precast production requirements, offering a full range of stressing pumps, jacks, grips accessories and related services. test carried out according to UNE 7474:92, should meet the following requirements. The residual elongation to failure may be evaluated in two ways. This can provide a prestressing tension to the mechanical component. The delivered coils shall not contain any welds that are carried out after the heat ]{n+c oE$A#n]~.\${,tKwn{q3 deviate at the anchorage are often subjected to this stress. requirements. When the prestressed members are straight or flat, in the direction of prestressing, theprestressing is called linear prestressing. Disclaimer/Publishers Note: The statements, opinions and data contained in all publications are solely This is further supported by the glassy temperature changes after fibre prestressing. DOI 10.1088/1742-6596/1973/1/012105, drce_ashrafalfeehan@uomustansiriyah.edu.iq, 1 This relationship shall be met, not only by the minimum guaranteed values, 2) High span-to-depth ratios Other Topics Pet Boarding Application to, Company has made additional purchase of fixed assets amounting to 187.61 crore it is out flow of cash for assets amounting to 187.61 crore it is out flow of cash for company and, As expected, the road racing helmet Lazer O2 with 24 air vents generates higher aerodynamic drag at all pitch angles (Head Positions 1, 2 & 3) compared to all other helmets.. "Elastic Fibre Prestressing Mechanics within a Polymeric Matrix Composite" Polymers 15, no. The useful life of the mechanical finishing device is prolonged. Unbonded . In a situation of employing wires with very severe straightening requirements, as occurs in the manufacture Mechanical properties of a unidirectional carbon prepreg before and after curing. For each effect, the benefits are listed. ; Badruddin, I.A. Experimental Evaluation of the Effect of Prestressing the Fibers in Two Directions on Certain Elastic Characteristic of Woven-Glass Reinforced Plastics. ; Daneshvar, A.; Akbari, S. Reduction of Thermal Residual Stresses of Laminated Polymer Composites by Addition of Carbon Nanotubes. To check. The 1000 hour relaxation level at a temperature of 20 1C, for an initial stress equal to The helical structure of commonly used seven-wire strands allowed estimation of the mechanical properties of the strand based on those of the central wire. For example, longitudinal prestressing of beams. sw^&{^VE+fGw-SnB6=2..\Rs%z-UqE& c7EanT>18XS'v={Q{3(KcQyhY7+l{`S Methods Phys. have a diameter of 4 mm or greater. All Rights Reserved. Pre-tensioning and Post-tensining: Effects of Tensile Prestress Level on Impact Value of 50 Vol% Continuous Unidirectional 0 Degree Oriented Carbon Fiber Reinforced Epoxy Polymer (CFRP). two fifth prestressing units adapted to be arranged in each opposite sides of the tool-head stand of the mechanical finishing device, wherein one of the fifth prestressing units is adapted to be mounted between two ends of the tool-head stand and the other fifth prestressing unit is adapted to be diagonally mounted in the side of the tool-head stand. In the cases of both certified and non-certified products, the Instruction requires that quality control tests be Wires are supplied in coils, where the reel diameter shall not be less than 250 times the Nishi, Y.; Okada, T.; Okada, S.; Hirano, M.; Matsuda, M.; Matsuo, A.; Faudree, M.C. 4 is a perspective view of a column of a mechanical finishing device with a prestressing device in accordance with the present invention; FIG. The reinforcement should be stored correctly classed by type, class and lot of origin. Thus, the preparation of an EPPMC using unidirectional carbon prepreg can be divided into three stages, see. the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, ; Hahn, H.T. Wang, B. Viscoelastically Prestressed Composites: Towards Process Optimisation and Application to Morphing Structures. It is recommended that the content, in percentage, of each of the chemical constituents of prestressing 36422:85, shall not be greater than 2%. b) At ultimate, during extreme events. between 1,000 and 4,000 kg. of grease, oil, paint, dust, soil or any other material detrimental to its conservation or subsequent When the level of prestressing is such that under tensile stresses due to service loads, the crack width is within the allowable limit, it is called Partial Prestressing (Type 3). Si 0.15 0.40 . To benefit from elastic fibre prestressing, the carbon prepregs need to be prestressed within the elastic region. Consistent models for the reduction factors of various properties were developed. This makes, For several years it has been apparent that the mechanical characteristics of insulating materials have a pronounced influence on their electrical breakdown by treeing. Editors select a small number of articles recently published in the journal that they believe will be particularly To further understand the EFP mechanics, we established a theoretical model to decouple the EFP principle and performed a comprehensive investigation into the prestress effects in terms of the static and dynamic mechanical properties, as well as the viscoelastic creep performance. Publishing. Advantages of Prestressing The continuous fibre reinforcements are prestressed and then impregnated into a polymeric matrix, where the prestress load is only removed after the resin is fully cured in order to produce an elastically prestressed polymeric matrix composite (EPPMC). Post-tensioning accordance with UNE 36461:80. Two- or three-wire strands are supplied in coils, where the inside diameter should be The geometry and weight properties of the strands, together with their corresponding ), expressed as a percentage. Shokrieh, M.M. They have been widely used in industries, such as automotive, tissue engineering, aerospace, and sustainable engineering [, There have been many techniques to reduce the generated thermal residual stress within a composite, including heat treatment after the curing process [, Depending on the mechanical properties of the fibre materials, fibre prestressing can be applied on both elastic fibres and viscoelastic fibres to produce (i) an elastically prestressed polymeric matrix composite (EPPMC) and (ii) a viscoelastically prestressed polymeric matrix composite (VPPMC) [, The EFP was first applied on polymeric composites by Zhigun [, For tensile properties of EPPMCs, Brown et al. and the customer. 1 Xikang Rd., Nanjing City, Jiangsu Province 210098, China. permission provided that the original article is clearly cited. A manual mechanical prestressing system was manufactured which used to apply a post-tension force to the high-stress steel wires in the curved slab member. taken from Table 32.3.b(corresponding to 60%, 70% and 80% of the maximum real unit load) given in UNE (Courtesy: The Concrete Products and Construction Company, COPCO, Chennai). Changes on characteristic parameters of the ceramic and in the coupling. When there are prestressing tendons parallel to two axes, it is called Biaxial The following classifications are discussed. In comparison to the non-prestressed control samples, the tensile strength is improved by 15%, the elongation at break by 11%, the impact strength by 11%, and the dynamic flexure modulus in both the elastic and rubbery plateau regions by ~30%. The objective of this study is to investigate and provide the mechanical properties of the new strand, as these properties are essential in the design and construction of prestressed concrete structures. a recess adapted to be defined in each component of the mechanical finishing device and receiving at least one of the prestressing units. Wang, B.; Fancey, K.S. value may vary between 195 and 205 kN/mm depending on the production process. Experiments were carried out using an accurate testing system for the development of empirical formulae to predict the deterioration of prestressing steel at elevated temperatures and after cooling. The system is used for strengthening reinforced concrete members. ; Lee, A.Y. These are expected to further promote industrial applications of the EFP technique to polymeric composite industries. S -- 0.040 performed on the steel (see Article 90) on acceptance, although test intensity will vary from one case to another. wherein the rigid prestressing units comprise: two first longitudinal prestressing units and three first lateral prestressing units adapted to be applied to the base of the mechanical finishing device, wherein each first longitudinal prestressing unit is adapted to be mounted in one of the sides of the base between two ends of the base and each first lateral prestressing unit is adapted to be mounted between two sides of the base; two second longitudinal prestressing units adapted to be applied to the moving base of the mechanical finishing device, wherein each second longitudinal prestressing unit is adapted to be mounted in one of the sides of the moving base between two ends of the moving base; three third longitudinal prestressing units adapted to be applied to the work table of the mechanical finishing device, wherein each third longitudinal prestressing unit is adapted to be mounted between two ends of the work table; two fourth prestressing units adapted to be applied to the column of the mechanical finishing device, wherein each fourth prestressing unit is adapted to be mounted cross a top and a bottom of the column; and. The useful life of the mechanical finishing device is prolonged. greater than, 200 mm shall not be less than 3.5%. Nucl. Enter your email address to subscribe to this blog and receive notifications of new posts by email. The main features of the system are as follows: (1) the prestressing forces are applied manually without using hydraulic jacks, (2) the prestressing level of the CFRP sheets can be controlled by using . ; resources, H.C., B.W. In all and C.Z. tolerances shall conform to the specifications given in UNE 36094-2:97. Journal of Physics: Conference Series, No special Knowledge of the mechanical properties of prestressing steel at elevated temperatures and after cooling is essential to the fire resistance design and post-fire evaluation of the residual load-carrying capacity of prestressed concrete structures. l) Skewed tensile strength (only for strands of rated diameter equal to or greater than 13 Linear Prestressing Mater. interesting to readers, or important in the respective research area. greater than 3%. (PDF) Mechanical properties of prestressing strands and how they tend to change under thermo-mechanical treatment Home Medicine General Practice Therapeutics Mechanical properties of. value may vary between 180 and 195 kN/mm depending on the production process. The system is used for strengthening reinforced concrete members. Results show that the system is efficient and practical for prestressing CFRP sheets to strengthen reinforced concrete beams. Tie Rod Diameter Up to 3 " 3 -4" 4 -7" 7" & over. Stage-I is the fibre prestressing stage, where constant tensile stress. Stages of Loading Wagner, H.D. of railway sleepers, (diameters between 7 and 10 mm), the relaxation value shall be agreed between the producer The 1000 hour relaxation level at a temperature of 20 1C, for an initial stress equal to By continuing to use this site you agree to our use of cookies. Pre-tensioned and grouted post-tensioned tendons are bonded tendons. recommended that the largest be employed in order to reduce the significance of any possible surface defects. Mechanical prestressing improves electrical strength | Semantic Scholar There is a strong mechanical influence on the growth of electrical trees in electrical insulation resins. This is the simplest type of prestressing, producing large prestressing forces. Drawn for Prestressing Concrete Pipe A649/A649M-99(2003) Standard Specification for Forged Steel . This number is an index of the ability of * This value is the one required by the article. Applying the post-tension prestressing force in the curved slab member increased the cracking and ultimate loads to about 311% and 381% respectively compared to the non-prestress curved slab, whereas the failure mode was occurred by flexural-tensile stress near the edge beams for both curved slabs. Therefore, the internal stress level of a composite can be regulated by adjusting the elastic fibre prestressing level. Fujian Provincial Key Laboratory of Terahertz Functional Devices and Intelligent Sensing, School of Mechanical Engineering and Automation, Fuzhou University, Fuzhou 350108, China. Therefore, the internal stress level within an EPPMC. PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362. To find out more, see our, Browse more than 100 science journal titles, Read the very best research published in IOP journals, Read open access proceedings from science conferences worldwide, Published under licence by IOP Publishing Ltd, Consultant Scientist / Engineer - Awerian, BAE Systems Applied Intelligence 2023 Engineering & Physics Graduate Programme, Electrical Engineer/Applied Physicist - Pulsed Power, Copyright 2023 IOP - The yield stress fy shall remain between 75% and 90% of the maximum unit load ; formal analysis, B.W. because it includes the failure section and adjacent zones, is affected by a possible stricture. Proceedings of the 2004 IEEE International Conference on Solid Dielectrics, 2004. ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:YEN, KELSON;HSU, CHEN-CHIEN;REEL/FRAME:011951/0428, Free format text: More economical sections. E-mail: 2014 American Society of Civil Engineers, Journal of Performance of Constructed Facilities, Prestress Losses and Flexural Behavior of Reinforced Concrete Beams Strengthened with Posttensioned CFRP Sheets, Investigation of RC Beams Strengthened with Prestressed NSM CFRP Laminates, Prestressed Carbon Fiber Reinforced Polymer Sheets for Strengthening Concrete Beams at Room and Low Temperatures, Prestressed CFRP for Strengthening of Reinforced Concrete Structures: Recent Developments at Empa, Switzerland, Design and Site Application of Prestressed Carbon-Fiber-Reinforced Polymer Sheets for Strengthening Concrete Structures, https://doi.org/10.1061/(ASCE)CF.1943-5509.0000478, 19962023, American Society of Civil Engineers. The tension is maintained during the solidification of the concrete and then released when fully solidified; thus, the elastic deformation of the steel rods is locked inside the concrete. The mechanism of the breakdown occurring when a dc ramp voltage is applied to low-density polyethylene (LDPE) and silane cross-linked PE at high temperatures is discussed, using experimental results, By clicking accept or continuing to use the site, you agree to the terms outlined in our. Struzziero, G.; Nardi, D.; Sinke, J.; Teuwen, J.J.E. (*total distance between nuts) Care must be taken not to exceed the required amount of shrinking. followed by a drawing process and another for stress-relieve. Because fibre prestressing is applied before resin curing, beyond the optimal prestress level, further increases in the creep stress may lead to premature failure of the fibres. relaxation. ; Rusnakova, S. A Review of Prestressed Fibre-Reinforced Polymer Matrix Composites. B.Tech in Civil Engineering from MIT Muzaffarpur and Diploma in Railway from IPWE as well as Civil Engineering from Govt. Ju OvW`5*53l!w>x_*--no0gaG h:V7ELGb/i.j|ngI; lh{&+vdB/r8QYL:$M9eAN=2Skr! ?YS>3?KPj~ ;Y@9X^{A2345eAPR#BvG6CH7l`MqN #_(g kfFGI65R/= Beyond the optimal prestress level however, there will be internal structural damages and premature failures which are able to change the in-plane stress levels within the composite. Significant features of this mechanical device are 1) the CFRP sheets are directly anchored to the device itself; 2) prestressing is easily achieved while the device is . prior to publication. C 0.58 0.88 . ; investigation, H.C., F.Y., B.W. adjacent to the one which is subject to the relaxation test. Prestressing of concrete can be classified in several ways. Mechanical Prestressing System for Strengthening Reinforced Concrete Members with Prestressed Carbon-Fiber-Reinforced Polymer Sheets A new, practical mechanical prestressing system was developed to prestress carbon-fiber-reinforced polymer (CFRP) sheets. 70% of the guaranteed maximum unit load (tensile strength), as determined by UNE 36422:85, Tensile testing was conducted using a universal testing machine to capture the mechanical properties of the PT strands, and the details of the test results are summarized in Table 3, . As a consequence of this, 1999 Annual Report Conference on Electrical Insulation and Dielectric Phenomena (Cat. MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR, DETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g. For the purposes of this Instruction, strands are those elements that meet the technical An Affiliate Member of ASCE American Society of Civil Engineers. Export citation and abstract The advantages of precast construction are as follows. For information purposes, the producer may provide relaxation values corresponding to an initial stress of Commercial insulation materials are often polymer composites containing additives of a particulate or laminate form that have a higher permittivity, a better breakdown resistance, and a greater mechanical roughness than the base resin. Typical values of span-to-depth ratios in slabs are given below. In the rubbery plateau region at 180 C, the prestress effects show a similar trend as with the glassy region and give a maximum improvement of 30.0% in flexure modulus. Partial Prestressing. The deviation coefficient D value in the skewed tensile test (UNE 36466:91) shall not be Less deformations (improved serviceability). It was found that there is an optimal level of EFP in order to maximise the prestress benefits, whilst the EFP is detrimental to the fibre/matrix interface. For the purposes of this Instruction, the esential properties used to define the quality of ; Schenk, M. Thermal Prestress in Composite Compliant Shell Mechanisms. ; data curation, F.Y. Conceptualization, B.W. These develop an initial compressive stress/strain in, Proceedings of the 7th International Conference on Properties and Applications of Dielectric Materials (Cat. It shall also be accompanied by the appropriate certificate of A prestressing device for a mechanical component of a mechanical finishing device has at least one rigid prestressing unit mounted in the mechanical component. ICSD 2004. LIU, Z.; ZHENG, X.; FAN, W.; WANG, F.; AHMED, S.; YAN, L. An Alternative Method to Reduce Process-Induced Deformation of CFRP by Introducing Prestresses. should not be greater than 2% (pre-straightened (decoiling) wires with stress-relieving When this information is not available, the relaxation To browse Academia.edu and the wider internet faster and more securely, please take a few seconds toupgrade your browser. Reduction of formwork This can provide a prestressing tension to the mechanical component. For informational purposes, the producer may provide relaxation values corresponding to an initial stress of Limited Prestressing b) At transfer of prestress to concrete. The main findings include: The EFP technique is able to be applied to a UD carbon prepreg material through a bespoke fibre prestressing rig to produce prestressed composite samples. ; methodology, B.W. progress in the field that systematically reviews the most exciting advances in scientific literature. When the prestressing is achieved by elements located outside the concrete, it is called external prestressing. In the past, many tests were carried out to evaluate the residual mechanical properties of prestressing steel after fire exposure. Find support for a specific problem in the support section of our website. period of storage on-site or in the workshop, in order to ensure that no detrimental changes Fancey, K.S. The bending and the deformation of the mechanical component can be prevented. With reference to FIG. @0p(U7-8PEs$NFKsd2pnF6].AnZ'. equal to 70% of the guaranteed maximum unit load, as determined by UNE Leverage your professional network, and get hired. Berzin, F.; Lemkhanter, L.; Marcuello, C.; Chabbert, B.; Agui-Bghin, V.; Molinari, M.; Castellani, R.; Vergnes, B. %PDF-1.2 % Influence of the Polarity of the Matrix on the Breakage Mechanisms of Lignocellulosic Fibers during Twin-Screw Extrusion. 32,4 and 32,5 in order to justify that the steel complies with the requirements contained in this Station, Karnataka The term of unit load is preferred over that of stress in order to take into account that the values recorded The other fibre ends were attached on the weight platform in order to be prestressed. There is an optimal EFP level to maximise the prestress benefits, i.e., 90 MPa for the applied CFRP prepreg. A rise in temperature would increase the Grade 1860 strands conforming to GB/T 5224, mostly used in Mainland China, and grade 1860 strands conforming to BS 5896, used in Europe and other countries, were tested. The designated fibre prestressing level is achieved by adjusting the weight applied on the platform. Tree growth is sensitive to, Proceedings of 1995 IEEE 5th International Conference on Conduction and Breakdown in Solid Dielectrics. The study aims to experiment with the use of a mechanical prestressing technique of thin curved sections to assess the prestressed force influencing the behavior of a curved slab at the initial and final loading stages. The design solution is simple and requires a summation of the, 1) Apparatus development to enable scaled construction and centrifuge testing of a variety of ribbed pile profiles and geometries. Although the EFP is active in improving the static mechanical performance of a composite, its mechanics on dynamic mechanical performance and viscoelasticity of a composite is still limited. Mechanical Prestressing System for Strengthening Reinforced Concrete Members with Prestressed Carbon-Fiber-Reinforced Polymer Sheets Suhaib S. Abdulhameed; Erjun Wu; and Bohai Ji Full text PDF Tools Share Abstract A new, practical mechanical prestressing system was developed to prestress carbon-fiber-reinforced polymer (CFRP) sheets. Force Measurement from Viscoelastically Recovering Nylon 6, 6 Fibres. The aim is to provide a snapshot of some of the Mechanical Systems Design and Analysis Engineer (Experienced) new. Rapid construction pre-stressed ties, GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS, TECHNICAL SUBJECTS COVERED BY FORMER USPC, TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION, Cutting by use of rotating axially moving tool, Machine frame including means to compensate for deformation, VICTOR TAICHUNG MACHINERY WORKS, CO., LTD., TAIWAN, ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:YEN, KELSON;HSU, CHEN-CHIEN;REEL/FRAME:011951/0428, PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362. You seem to have javascript disabled. The first one is reinforced with micro steel fibers while the second one is reinforced with micro steel fibers in addition to four high-stress steel wires. In this type of prestressing, the devices includes weights with or without ever The inside diameter of the coil or tolerances shall conform to the requirements given in UNE 36094-3:97. Current Planning Division On-line Project Application. It is obviously an electrically driven process; no volts, no trees. Effect of Tensile . The Effects of Fibre Pre-Stressing on the Impact Performance of Composite Laminates. Higher moment of inertia (higher stiffness) To do this, the decay of the mechanical properties of the prestressing steel needs to be determined first. - The yield stress fy shall remain between 0.88 and 0.95 of the maximum unit load Because the elastic recovery of the fibre is usually instant, the elastic strain locked inside an EPPMC, i.e.. A new, practical mechanical prestressing system was developed to prestress carbon-fiber-reinforced polymer (CFRP) sheets. ; validation, C.Z., X.C., W.N. Prestressing bars are only produced in a limited number of factories, and in general, for certain Parlevliet, P.P. * This value is the one required by the article. This site uses cookies. steels , lies between the values given in Table 32.2, in order to achieve acceptable mechanical properties. 1. TYPES of PRESTRESSED CONCRETE: Prestressing of concrete is classified into different types as per applied load or force used to do prestress. Assigned to VICTOR TAICHUNG MACHINERY WORKS, CO., LTD. VICTOR TAICHUNG MACHINERY WORKS, CO., LTD. fmax This limitation shall be met, not only by the minimum guaranteed values, but The wires used in the strands shall be capable of withstanding the number of reverse We present an energy. To evaluate the effects of prestress level on viscoelastic performance of composites, tensile creep testing was also carried out on prestressed samples at different temperatures, which include 25 C, 50 C, 75 C, 100 C, 125 C. For wires intended for the several techniques or approaches, or a comprehensive review paper with concise and precise updates on the latest Knowledge of the mechanical properties of prestressing steel at elevated temperatures and after cooling is essential to the fire resistance design and post-fire evaluation of the residual load-carrying capacity of prestressed concrete structures.