Prestress calculation method and device for unbonded prestressed concrete containment reinforcement

Abstract

The invention discloses a prestress calculation method and device for unbonded prestressed concrete containment reinforcement. The method comprises the steps that the first total deformation amount of a single unbonded steel strand under the action of a preset single load is obtained; obtaining a first unit stress variable of the unbonded steel strand according to the first total deformation and the elastic modulus of the steel strand; according to the first unit stress variable and a corresponding second unit stress variable of the bonded steel strand, obtaining a first compensation stress load required for converting the bonded steel strand into an unbonded steel strand; and according to the second prestress of the bonded steel strand under the preset single load effect and the first compensation stress load, the first prestress of the unbonded steel strand under the preset single load effect is determined. According to the method, the first prestress of the steel strand under the action of the preset single load can be determined more accurately, and support is provided for stress calculation of concrete under the condition of load combination in subsequent unbonded prestressed concrete containment design.

Description

Technical Field

[0001] The invention belongs to the technical field of nuclear power, and in particular relates to a prestress calculation method and device for unbonded prestressed concrete containment reinforcement and a containment. Background Art

[0002] Prestressed concrete containment includes concrete and reinforcement (prestressed tendons). Among them, the prestressed tendons are multiple bundles, and each bundle of prestressed tendons contains multiple steel strands, which can be used to provide prestressing force to resist accident pressure, regardless of their bearing capacity contribution. Concrete is used to bear the loads generated by the prestressed tendons and the stress changes under the load combination. The combination of the two can make the prestressed concrete containment have better crack resistance and durability while bearing the load.

[0003] In the process of designing the prestressed concrete containment, the prestress change of the unbonded prestressed concrete containment reinforcement under the preset load will be determined first, and then the stress demand of the concrete part will be designed based on the prestress change of the unbonded prestressed concrete containment reinforcement.

[0004] However, in the prior art, the prestress change of the unbonded prestressed concrete containment reinforcement is replaced by the prestress of the bonded prestressed concrete containment reinforcement. However, the deformation mode of the reinforcement and concrete in the unbonded prestressed concrete containment is different from that in the bonded prestressed concrete containment. Therefore, the stress change of the bonded reinforcement is used to replace the stress change of the unbonded reinforcement, resulting in a lower accuracy of the prestress calculation of the unbonded prestressed concrete containment reinforcement, which reduces the accuracy of the concrete stress calculation in the design process of the unbonded prestressed concrete containment. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a method, device and system for calculating the prestress of the reinforcement of the unbonded prestressed concrete containment shell in view of the above-mentioned deficiencies in the prior art. By using this method, the deformation mode of the reinforcement in the concrete shell of the unbonded prestressed concrete containment shell can be accurately simulated, and the accuracy of the prestress calculation of the reinforcement of the unbonded prestressed concrete containment shell can be effectively improved.

[0006] In a first aspect, the present invention provides a method for calculating the prestress of unbonded prestressed concrete containment reinforcement, comprising:

[0007] Obtaining a first total deformation of a single unbonded steel strand under a preset single load;

[0008] According to the first total deformation and the elastic modulus of the steel strand, a first unit stress variable of the unbonded steel strand is obtained;

[0009] According to the first unit stress variable and the corresponding second unit stress variable of the bonded steel strand, a first compensating stress load required for the bonded steel strand to be transformed into an unbonded steel strand is obtained;

[0010] The first prestress of the unbonded steel strand under the preset single load is determined based on the second prestress of the bonded steel strand under the preset single load and the first compensating stress load.

[0011] In some embodiments, the step of obtaining the total deformation of a single steel strand under a preset single load includes:

[0012] The second total deformation of a single bonded steel strand under a preset single load is determined as the first total deformation of a single unbonded steel strand under a preset single load, which specifically includes:

[0013] The second total deformation of the bonded steel strand under a preset single load is calculated according to the following formula (1):

[0014]

[0015] Where, ΔL is the second total deformation of a single bonded steel strand (m); L is the total length of a single steel strand before the load is applied (m); E s is the elastic modulus of the steel strand (MPa); s is the distance between the finite element unit and the starting point of the steel strand (m); Δσ 有粘结 is the second unit stress variable of the bonded prestressed steel strand under the preset single load (MPa);

[0016] The second total deformation is determined as the first total deformation of a single unbonded steel strand under a preset single load.

[0017] In some embodiments, the calculating the first unit stress variable of the unbonded steel strand according to the first total deformation and the elastic modulus of the steel strand comprises:

[0018] Assuming that the stress change of the entire unbonded steel strand is uniform under the action of a preset single load, the first unit stress variable of the unbonded steel strand is calculated according to the following formula (2):

[0019] Δσ PE =ΔL / L×E s (2)

[0020] Among them, Δσ PE is the first unit stress variable of the unbonded prestressed steel strand (MPa), ΔL is the first total deformation of a single unbonded steel strand (m); L is the total length of a single unbonded steel strand before the load is applied (m); E sis the elastic modulus of the unbonded steel strand (MPa).

[0021] In some embodiments, the calculating, based on the first unit stress variable and the corresponding second unit stress variable of the bonded steel strand, the first compensating stress load required for the bonded steel strand to be transformed into the unbonded steel strand specifically includes:

[0022] The second compensating stress load required for the unbonded steel strand is calculated according to the following formula (3):

[0023] σ 补偿 =Δσ PE -Δσ 有粘结 (3)

[0024] Among them, σ 补偿 The second compensating stress load (MPa) required for the steel strand to transform from a bonded steel strand to an unbonded steel strand;

[0025] The second compensating stress load is corrected according to the following formula (4) to obtain the first compensating stress load required for the bonded steel strand to be transformed into an unbonded steel strand, so as to compensate for the deviation caused by the elastic deformation of the concrete:

[0026]

[0027] in, is the first compensating stress load (MPa) required for the steel strand to transform from a bonded steel strand to an unbonded steel strand; 补偿 A is the second compensating stress load (MPa) required for the steel strand to transform from a bonded steel strand to an unbonded steel strand; s is the area of ​​each strand (m 2 );s p is the distance of the steel strand (m); t is the thickness of the containment (m); E c is the elastic modulus of concrete (MPa).

[0028] In some embodiments, determining the first prestress of the unbonded steel strand under the preset single load according to the second prestress of the bonded steel strand under the preset single load and the first compensating stress load comprises:

[0029] Using finite element software, the second prestress of the bonded steel strands in the bonded prestressed concrete containment under the action of a preset single load is obtained, and

[0030] Obtaining a first compensating force of a bonded steel strand in a bonded prestressed concrete containment under a first compensating stress load;

[0031] The second prestressing force and the first compensating force are combined to obtain a first prestressing force of the unbonded steel strands in the unbonded prestressed concrete containment under a preset single load.

[0032] In some embodiments, the method further comprises:

[0033] The first stress of concrete in the unbonded prestressed concrete containment is calculated based on the determined first prestress of the unbonded steel strands under the preset single load.

[0034] In a second aspect, the present invention further provides a prestress calculation device for unbonded prestressed concrete containment reinforcement, the device comprising:

[0035] An acquisition module, which is configured to acquire a first total deformation of a single unbonded steel strand under a preset single load;

[0036] A first obtaining module, connected to the acquisition module, is configured to obtain a first unit stress variable of the unbonded steel strand according to the first total deformation and the elastic modulus of the steel strand;

[0037] A second obtaining module, connected to the first obtaining module, is configured to obtain a first compensating stress load required for converting the bonded steel strand into the unbonded steel strand based on the first unit stress variable and the corresponding second unit stress variable of the bonded steel strand;

[0038] The determination module is connected to the second obtaining module and is configured to determine the first prestress of the reinforcement of the unbonded prestressed concrete containment shell under the preset single load based on the second prestress of the bonded prestressed concrete containment shell under the preset single load and the first compensating stress load.

[0039] In some embodiments, the second obtaining module is further used to

[0040] The second compensating stress load required for the unbonded steel strand is calculated according to the following formula (3):

[0041] σ 补偿 =Δσ PE -Δσ 有粘结 (3)

[0042] Among them, σ 补偿 The second compensating stress load (MPa) required for the steel strand to transform from a bonded steel strand to an unbonded steel strand;

[0043] The second compensating stress load is corrected according to the following formula (4) to obtain the first compensating stress load required for the bonded steel strand to be transformed into an unbonded steel strand, so as to compensate for the deviation caused by the elastic deformation of the concrete:

[0044]

[0045] in, is the first compensating stress load (MPa) required for the steel strand to transform from a bonded steel strand to an unbonded steel strand; 补偿 A is the second compensating stress load (MPa) required for the steel strand to transform from a bonded steel strand to an unbonded steel strand; s is the area of ​​each strand (m 2 );s p is the distance of the steel strand (m); t is the thickness of the containment (m); E c is the elastic modulus of concrete (MPa).

[0046] In a third aspect, the present invention further provides a design device for an unbonded prestressed concrete containment shell, comprising:

[0047] The prestress calculation device for unbonded prestressed concrete containment reinforcement as described in any one of the above items is used to determine the first prestress of the unbonded steel strand under a preset single load;

[0048] A concrete design module, connected to the prestress calculation device, for combining the first prestress and a preset single load to design the concrete in the unbonded prestressed concrete containment;

[0049] The containment design module is connected to the concrete design module and is used to design the containment according to the concrete.

[0050] In a fourth aspect, the present invention further provides an unbonded prestressed concrete containment, comprising: concrete and a steel strand composed of unbonded steel strands,

[0051] The unbonded prestressed concrete containment shell is designed by using the arrangement device as described above.

[0052] The method for calculating the prestress of the reinforcement of the unbonded prestressed concrete containment shell of the present invention obtains the first total deformation of a single unbonded steel strand, calculates the first unit stress variable of the unbonded steel strand, and calculates the first compensating stress load required for the bonded steel strand to be transformed into the unbonded steel strand. Because the first compensating stress load compensates for the uncoordinated deformation of the unbonded steel strand and the concrete deformation, the stress change of the reinforcement in the concrete shell of the unbonded prestressed concrete containment shell can be accurately simulated. Therefore, the first prestress of the steel strand under the action of a preset single load can be more accurately determined. Therefore, it can more accurately provide support for the stress calculation of concrete in the subsequent unbonded prestressed concrete containment shell design under load combination. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1A flowchart of a method for calculating prestress of unbonded prestressed concrete containment reinforcement provided by an embodiment of the present invention;

[0054] Figure 2 A flowchart of an application example of a method for calculating prestress of unbonded prestressed concrete containment reinforcement provided by an embodiment of the present invention;

[0055] Figure 3a and Figure 3b Schematic diagrams of displacement of a prestressed concrete containment with and without bonding under accident pressure loads provided in embodiments of the present invention;

[0056] Figure 4a and Figure 4b Schematic diagrams of stress of prestressed tendons of a prestressed concrete containment with and without bonding provided in embodiments of the present invention;

[0057] Figure 5 A schematic diagram of the steel strand stress of a typical inverted U-shaped prestressed tendon with and without bonded prestressed containment provided in an embodiment of the present invention;

[0058] Figure 6 A schematic diagram of the stress of a typical horizontal prestressed steel strand of a prestressed containment shell with or without bonding provided by an embodiment of the present invention;

[0059] Figure 7 A schematic diagram of the steel strand stress of a typical dome horizontal prestressed steel strand with and without bonded prestressed containment provided in an embodiment of the present invention;

[0060] Figure 8 A structural diagram of a prestress calculation device for unbonded prestressed concrete containment reinforcement provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0061] In order to make those skilled in the art better understand the technical scheme of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and Examples. It should be understood that the specific embodiments described herein are only intended to explain the application, rather than to limit the application. For those skilled in the art, the application can be implemented when some details in these specific details are not needed. The following description of the embodiments is only for providing a better understanding of the application by illustrating the examples of the application.

[0062] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "include..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0063] In the related art, it is difficult to simulate unbonded reinforcement in ANSYS software. The prestress calculation of unbonded prestressed concrete containment reinforcement is replaced by the prestress approximation of bonded prestressed concrete containment reinforcement. However, because for bonded prestressed concrete containment, its steel strands and concrete deform in coordination; while for unbonded prestressed concrete containment, the steel strands can still slide in the containment after the concrete is poured, which is not coordinated with the concrete deformation. Under the action of load, the internal stress of the reinforcement will be redistributed due to sliding. That is, the deformation mode of the reinforcement and concrete in the unbonded prestressed concrete containment is different from that of the reinforcement and concrete in the bonded prestressed concrete containment. Therefore, the stress change of the bonded reinforcement is used to replace the stress change of the unbonded reinforcement, resulting in a lower accuracy of the prestress calculation of the unbonded prestressed concrete containment, which reduces the accuracy of the concrete stress calculation in the design process of the unbonded prestressed concrete containment.

[0064] That is, unlike the bonded prestressed concrete containment, the prestress in the unbonded prestressed concrete containment under a preset load does not change in tandem with the deformation of the shell, but is redistributed as the prestressed tendons slide inside. Therefore, accurate simulation of the changes in the unbonded prestress can improve the accuracy of concrete stress calculation during the design of the unbonded prestressed concrete containment.

[0065] The inventors have found that the total deformation of the steel strand is determined by first analyzing a single load based on the reinforcement in the bonded prestressed concrete. Then, the unbonded steel strand is set to slide freely along the length direction of the steel strand. Under the action of a preset single load, the stress change of the entire steel strand is uniform, thereby obtaining the unit stress variable of each unbonded steel strand. Finally, the unit stress variable of each steel strand is subtracted from the initial calculated stress variable of each finite element unit of the steel strand to obtain the compensation stress variable of each finite element unit of the unbonded steel strand. This compensation stress variable is applied as a load condition to the bonded prestressed model, which can accurately simulate the stress change of the reinforcement in the concrete shell of the unbonded prestressed concrete containment. This method overcomes the problem of uncoordinated deformation of the steel strand and concrete in the unbonded prestressed concrete, making the prestress calculation of the reinforcement of the unbonded prestressed concrete containment more accurate.

[0066] Based on this, in order to solve the problems of the prior art, the present invention proposes a prestress calculation method and device for unbonded prestressed concrete containment reinforcement, which can accurately simulate the stress changes of the reinforcement in the concrete shell of the unbonded prestressed concrete containment, and improve the accuracy of the prestress calculation of the unbonded prestressed concrete containment reinforcement.

[0067] Embodiment 1:

[0068] like Figure 1 As shown, this embodiment provides a method for calculating the prestress of unbonded prestressed concrete containment reinforcement, which is mainly used in the design of the containment of a nuclear power system, and includes steps S1 to S4:

[0069] Step S1. Obtain a first total deformation of a single unbonded steel strand under a preset single load.

[0070] Here, the preset single load may refer to an accident pressure load or other loads. In some embodiments, the accident pressure load may be set according to the reactor type of the containment vessel to ensure that the containment vessel can maintain integrity and prevent radioactive substances from leaking into the environment in extreme cases.

[0071] The unbonded steel strand can be a PE (Polyethylene) unbonded steel strand. The steel strand is wrapped with a PE sheath on the outside and filled with anti-corrosion lubricating grease on the inside. It has a relatively low friction coefficient and can provide a higher effective prestress. It can be used in the prestressed system of the containment of a nuclear power plant to reduce the amount of prestressed materials and save construction time. It should be noted that unbonded steel strands can also be designed in other ways, and this application does not limit this.

[0072] During implementation, the first total deformation of a single unbonded steel strand under a preset single load is obtained, which can be specifically obtained according to the total deformation of a single bonded steel strand in bonded prestressed concrete. This is because, under the preset single load, the total deformation of the bonded prestressed concrete containment reinforcement and the total deformation of the unbonded prestressed concrete containment reinforcement are the same.

[0073] like Figure 3a and Figure 3b As shown in the figure, the displacement of the unbonded prestressed concrete containment is very different from that of the bonded prestressed concrete containment. Therefore, it can be considered that under the action of a preset single load, the total deformation of the bonded prestressed concrete containment reinforcement is the same as the total deformation of the unbonded prestressed concrete containment reinforcement.

[0074] Step S2. Obtain a first unit stress variable of the unbonded steel strand according to the first total deformation and the elastic modulus of the steel strand.

[0075] Here, the elastic modulus of the steel strand is an indicator of the material's ability to resist deformation within the elastic range. The elastic modulus of high-strength prestressed steel strands is generally between 190 GPa and 210 GPa. In some embodiments, the selection of the elastic modulus of the steel strand must also comply with the requirements of relevant national standards or industry specifications.

[0076] The first unit stress variable is the stress variable of the finite element unit of the first total deformation along the length direction of the steel strand. It can be understood that in this embodiment, the unbonded steel strand slides freely along the length direction of the steel strand, and under the action of a preset single load, the stress change of the entire steel strand is uniform.

[0077] like Figure 4a and Figure 4b As shown in FIG. 1 , under the action of a preset single load (accident pressure load), the stress of each steel strand of the unbonded prestressed concrete containment is basically uniform.

[0078] During implementation, the strain variable of the finite element unit of the unbonded steel strand can be determined by the first total deformation of the single unbonded steel strand and the total length of the single steel strand before the application of a preset single load; then, the first unit stress variable of the unbonded steel strand is obtained based on the strain variable of the finite element unit of the unbonded steel strand and the elastic modulus of the steel strand.

[0079] Step S3. Obtain a first compensating stress load required for converting the bonded steel strand into an unbonded steel strand based on the first unit stress variable and the corresponding second unit stress variable of the bonded steel strand.

[0080] Here, the existing prestress calculation software for bonded prestressed concrete containment reinforcement can be used to perform finite element calculation extraction to obtain the second unit stress variables of the bonded steel strands.

[0081] During implementation, the second unit stress variable of the bonded steel strand under the same preset single load can be subtracted from the first unit stress variable, and the difference obtained is the stress load required to compensate for the conversion of the bonded steel strand into an unbonded steel strand.

[0082] In some embodiments, the stress load required to compensate for the conversion of bonded steel strands to unbonded steel strands can also be taken into consideration. When it is directly applied to the prestress calculation model of the bonded prestressed concrete containment reinforcement for calculation, deviations will occur due to the elastic deformation of the concrete. It is necessary to correct the stress load required to compensate for the conversion of bonded steel strands to unbonded steel strands to obtain the first compensating stress load.

[0083] Step S4. Determine the first prestress of the unbonded steel strand under the preset single load based on the second prestress of the bonded steel strand under the preset single load and the first compensating stress load.

[0084] Here, the second prestress represents the force generated by the bonded steel strands on the concrete under the preset single load. During implementation, the second prestress of the bonded steel strands under the preset single load can be extracted by finite element calculation using the existing prestress calculation software for bonded prestressed concrete containment reinforcement.

[0085] The first prestress represents the force generated by the unbonded steel strand on the concrete under the preset single load. During implementation, the second prestress generated by the bonded steel strand on the concrete under the preset single load and the compensating force generated by the bonded steel strand on the concrete under the first compensating stress load are combined to determine the first prestress of the unbonded steel strand under the preset single load.

[0086] Specifically, the force (second prestress) generated by the bonded steel strands on the concrete under the action of a preset single load and the compensatory force generated by the bonded steel strands on the concrete under the action of the first compensatory stress load applied by the bonded steel strands can be simulated in the existing prestress calculation software for bonded prestressed concrete containment respectively. The force (first prestress) generated by the unbonded steel strands on the concrete under the action of a preset single load can be obtained by combining the force generated by the bonded steel strands on the concrete and the compensatory force using the existing prestress calculation software for bonded prestressed concrete containment.

[0087] In some other embodiments, in the existing prestress calculation software for bonded prestressed concrete containment, the second unit stress variable of each bonded steel strand can be superimposed with the first compensating stress load of the corresponding unit to determine the actual unit stress variable of the unbonded steel strand; then, the first prestress of the unbonded steel strand under the action of a preset single load is determined based on the actual unit stress variable of the unbonded steel strand.

[0088] In this embodiment, by obtaining the first total deformation of a single unbonded steel strand, calculating the first unit stress variable of the unbonded steel strand, and calculating the first compensating stress load required for converting a bonded steel strand into an unbonded steel strand, the stress change of the reinforcement in the concrete shell of the unbonded prestressed concrete containment can be accurately simulated because the first compensating stress load compensates for the uncoordinated deformation of the unbonded steel strand and the concrete deformation. Therefore, the first prestress of the steel strand under the preset single load can be more accurately determined. Therefore, it can provide more accurate support for the stress calculation of concrete in the subsequent unbonded prestressed concrete containment design under load combination.

[0089] In some embodiments, step S1 includes step S11:

[0090] Step S11. Determine the second total deformation of a single bonded steel strand under a preset single load as the first total deformation of a single unbonded steel strand under a preset single load, which specifically includes:

[0091] The second total deformation of the bonded steel strand under a preset single load is calculated according to the following formula (1):

[0092]

[0093] Where, ΔL is the second total deformation of a single bonded steel strand (m); L is the total length of a single steel strand before the load is applied (m); E s is the elastic modulus of the steel strand (MPa); s is the distance between the finite element unit and the starting point of the steel strand (m); Δσ 有粘结 is the second unit stress variable of the bonded prestressed steel strand under the preset single load (MPa);

[0094] The second total deformation is determined as the first total deformation of a single unbonded steel strand under a preset single load.

[0095] It is understandable that for bonded steel strands (bonded prestressed concrete containment reinforcement) and unbonded steel strands (unbonded prestressed concrete containment reinforcement), under the same load, although the stress distribution of the steel strands is different, the total deformation of a single steel strand should be the same. Therefore, a single load analysis is performed on the unbonded prestressed concrete containment reinforcement according to the design method of bonded prestressed concrete containment reinforcement, and the deformation of all finite element units in each steel strand is extracted and summed to obtain the total deformation (second total deformation), which is also the total deformation of the unbonded prestressed concrete containment reinforcement under the same single load (i.e., the first total deformation).

[0096] For example, according to the design method of bonded prestressed concrete containment reinforcement, through finite element extraction, for a steel strand length of 157.9284 m, according to formula (1), the length change of a single bonded steel strand under the accident pressure load is calculated to be 0.02718 m, and the length change of a single unbonded steel strand under the accident pressure load is also 0.02718 m.

[0097] In this embodiment, the second total deformation of a single bonded steel strand under a preset single load is determined as the first total deformation of a single unbonded steel strand under a preset single load, thereby determining the total deformation of the unbonded prestressed concrete containment reinforcement under the preset single load, thereby providing a basis for the subsequent prestress calculation of the unbonded prestressed concrete containment reinforcement.

[0098] In some embodiments, step S2 specifically includes:

[0099] Assuming that the stress change of the entire unbonded steel strand is uniform under the action of a preset single load, the first unit stress variable of the unbonded steel strand is calculated according to the following formula (2):

[0100] Δσ PE =ΔL / L×E s (2)

[0101] Among them, Δσ PE is the first unit stress variable of the unbonded prestressed steel strand (MPa), ΔL is the first total deformation of a single unbonded steel strand (m); L is the total length of a single unbonded steel strand before the load is applied (m); E s is the elastic modulus of the unbonded steel strand (MPa).

[0102] Here, the strain variable of the finite element unit of the unbonded steel strand can be determined according to △L / L; and the stress variable of the finite element unit can be obtained by dividing the strain variable of the finite element unit by the elastic modulus of the steel strand, that is, the first unit stress variable of the unbonded steel strand can be obtained.

[0103] It should be noted that under the preset single load, the stress change of the whole unbonded steel strand is uniform, because the unbonded steel strand can still slide freely along the length direction of the steel strand in the containment after the concrete is poured. Therefore, under the preset single load, the stress change (△σ PE ) is also uniform, so the first unit stress variable of the unbonded steel strand can be obtained according to the above formula (2).

[0104] In this embodiment, by setting the stress change of the entire unbonded steel strand to be uniform under a preset single load, the first unit stress variable of the unbonded steel strand is calculated, which can simulate the uncoordinated deformation of the unbonded steel strand and the concrete deformation, and more accurately simulate the stress change of the reinforcement in the concrete shell of the unbonded prestressed concrete containment, providing support for more accurate determination of the first prestress of the steel strand under a preset single load.

[0105] In some embodiments, step S3 specifically includes steps S31 to S32:

[0106] Step S31. Calculate the second compensating stress load required for the unbonded steel strand according to the following formula (3):

[0107] σ 补偿 =Δσ PE -Δσ 有粘结 (3)

[0108] Among them, σ 补偿 It is the second compensating stress load (MPa) required for the steel strand to transform from a bonded steel strand to an unbonded steel strand.

[0109] Here, the second compensating stress load is the stress load required to compensate for the transformation of each finite element unit from a bonded steel strand to an unbonded steel strand.

[0110] Step S32. The second compensating stress load is corrected according to the following formula (4) to obtain the first compensating stress load required for converting the bonded steel strand into the unbonded steel strand, so as to compensate for the deviation caused by the elastic deformation of the concrete:

[0111]

[0112] in, is the first compensating stress load (MPa) required for the steel strand to transform from a bonded steel strand to an unbonded steel strand; 补偿 A is the second compensating stress load (MPa) required for the steel strand to transform from a bonded steel strand to an unbonded steel strand; s is the area of ​​each strand (m2 );s p is the distance of the steel strand (m); t is the thickness of the containment (m); E c is the elastic modulus of concrete (MPa).

[0113] Here, directly applying the second compensating stress load to the model for calculation will cause deviation due to the elastic deformation of concrete, so the second compensating stress load needs to be corrected.

[0114] The cross-sectional shape of the steel strand can be approximately circular. The diameter and corresponding cross-sectional area of ​​the standard prestressed steel strand can be determined according to the specific product specifications. For example, the commonly used prestressed steel strand diameters are 12.7 mm, 15.2 mm and several other specifications. For a standard prestressed steel strand with a diameter of 15.2 mm, its cross-sectional area is about 181 square millimeters.

[0115] The distance between the steel strands is the arrangement spacing of the prestressed tendons in the containment. The distance between the steel strands in the unbonded prestressed concrete containment can be designed according to the relevant design specifications in this field.

[0116] The thickness of the containment vessel is generally between tens of centimeters and one meter. The thickness of the containment vessel can be determined based on factors such as design standards, nuclear power plant type, and geographical location.

[0117] The elastic modulus of concrete refers to the rigidity of concrete in the direction of force. The elastic modulus of concrete can be between 20GPa and 50GPa. The specific value of the elastic modulus of concrete can be determined according to the design requirements of the containment.

[0118] In this embodiment, by calculating the second compensating stress load required for the unbonded steel strands and determining the first compensating stress load required for the conversion of the bonded steel strands into the unbonded steel strands, the deviation caused by the elastic deformation of the concrete under the action of a preset single load can be compensated, thereby facilitating a more accurate description of the prestressing of the unbonded prestressed concrete containment reinforcement in the existing bonded prestressed concrete containment system.

[0119] In some embodiments, step S4 includes steps S41 to S42:

[0120] Step S41. Using finite element software, obtain the second prestress of the bonded steel strands in the bonded prestressed concrete containment under a preset single load, and,

[0121] A first compensating force of a bonded steel strand in a bonded prestressed concrete containment under the action of a first compensating stress load is obtained.

[0122] Here, the second prestress of the bonded steel strands in the bonded prestressed concrete containment under the preset single load can be obtained by applying a preset single load to the bonded prestressed concrete containment in the existing prestress calculation software for the bonded prestressed concrete containment reinforcement (e.g., finite element software). For example, the second prestress is the force composed of the second unit stress variables.

[0123] By applying the first compensating stress load to the bonded prestressed concrete containment, the compensating force of the first compensating stress load on the concrete is determined. For example, the first compensating force is the force formed by each first compensating stress load.

[0124] Step S42. Combine the second prestress and the first compensating force to obtain a first prestress of the unbonded steel strands in the unbonded prestressed concrete containment under a preset single load.

[0125] Here, in the finite element software, the second prestress and the first compensating force are combined to obtain the first prestress of the unbonded steel strands in the unbonded prestressed concrete containment under the action of a preset single load.

[0126] For example, by post-processing the analysis results of the bonded prestressed containment, it is found that the first prestress of the unbonded prestressed steel strand under the accident pressure load is 10.95 MPa. Figure 5 As shown, the steel strand stress of the typical inverted U-shaped prestressed steel strand of the unbonded prestressed containment is basically uniform and very close to the theoretical calculated value of 10.95 MPa. It can be seen that the prestress calculation of the unbonded prestressed concrete containment of this embodiment has a higher accuracy.

[0127] In this embodiment, by obtaining the second prestress of the bonded prestressed concrete containment under a preset single load, and combining the second prestress with the first compensating stress load, a more accurate first prestress of the unbonded steel strands in the unbonded prestressed concrete containment under a preset single load can be obtained.

[0128] In some embodiments, the method further comprises:

[0129] The first stress of concrete in the unbonded prestressed concrete containment is calculated based on the determined first prestress of the unbonded steel strands under the preset single load.

[0130] Here, the first stress may be the ultimate bearing capacity of concrete or other stress.

[0131] In the existing bonded prestressed concrete containment system, the first prestress of the unbonded steel strand under the preset single load is determined to accurately simulate the force of the reinforcement on the concrete in the unbonded prestressed concrete containment. That is, in the existing bonded prestressed concrete containment system, a preset single load is applied to the concrete of the bonded prestressed concrete containment to perform stress analysis to obtain a first analysis result of the concrete, and a first compensation load is applied to the concrete of the bonded prestressed concrete containment to perform stress analysis to obtain a second analysis result of the concrete, and then the first analysis result is combined with the second analysis result to obtain the analysis result (i.e., the first stress) of the concrete of the unbonded prestressed concrete containment.

[0132] In some other embodiments, the first stress of concrete in the unbonded prestressed concrete containment is calculated by obtaining the second unit stress variable of the bonded steel strand and the first compensating stress load of the corresponding unit in the existing bonded prestressed concrete containment system, determining the stress variable of each unit of the unbonded steel strand, and then applying the stress variable of each unit of the unbonded steel strand to the existing bonded prestressed concrete containment system to simulate the calculation of the first stress of concrete in the unbonded prestressed concrete containment.

[0133] In this embodiment, the first stress of concrete in the unbonded prestressed concrete containment is calculated by the first prestress. Since the first prestress is load compensated, the stress change of the reinforcement in the concrete shell of the unbonded prestressed concrete containment can be accurately simulated in the existing bonded prestressed concrete containment system, thereby improving the accuracy of concrete stress calculation of the unbonded prestressed concrete containment.

[0134] Embodiment 2:

[0135] The specific implementation process of the above method is described below in conjunction with specific application examples.

[0136] This embodiment proposes a method for calculating the prestress of a PE unbonded prestressed concrete containment, which can simulate the stress distribution of PE unbonded steel strands under a single load, and then obtain the analysis results of the PE unbonded prestressed concrete containment under a single load, providing a basis for subsequent load combination and reinforcement calculation.

[0137] To achieve the above objectives, Figure 2 As shown, the method adopted by the present invention includes steps 1 to 4:

[0138] Step 1. Determine the distribution principle of PE unbonded steel strand (prestressed tendon) stress based on the characteristics of PE unbonded steel strand.

[0139] Specifically, before calculating the stress distribution of PE unbonded prestressed steel tendons under a single load, two basic principles should be determined first:

[0140] 1) PE unbonded prestressed steel strand can slide freely along the length of the steel strand. Under a single load, the stress change of the entire steel strand is uniform.

[0141] 2) After single load analysis, the prestress change determined according to the first principle is the actual prestress change and does not need to be corrected again in the load combination or reinforcement calculation.

[0142] Step 2. Perform a single load analysis for bonded tendons.

[0143] Specifically, for bonded and PE unbonded prestressed systems, under the same load, although the stress distribution of the internal steel bundles is different, the total deformation of a single steel bundle is the same. Therefore, a single load analysis is performed on the PE unbonded steel bundle according to the design method of the bonded system, and the deformation of all units (finite element units) in each steel bundle is extracted and summed to obtain the total deformation, which is also the total deformation of the PE unbonded steel bundle under the same single load. The calculation formula is as follows:

[0144]

[0145] Where: ΔL—total deformation of a single tendon after analysis of bonded prestressed tendons (m);

[0146] L—total length of a single steel strand before loading (m);

[0147] E s —Elastic modulus of steel strand (MPa);

[0148] s—the distance between the unit and the starting point of the steel bundle (m);

[0149] Δσ 有粘结 —Calculated stress change (MPa) in each element of the tendon after analysis of bonded prestressed tendons.

[0150] Reference Figure 3a and Figure 3b ,in Figure 3a and Figure 3b are the displacements of the prestressed concrete containment with and without bonding under accident pressure load, respectively. Figure 3a and Figure 3b As shown, the displacement of the unbonded prestressed concrete containment is very different from that of the bonded prestressed concrete containment.

[0151] Step 3. According to the distribution principle of PE unbonded steel bundle stress, the compensation stress of PE unbonded steel bundle is calculated and substituted into the bonded containment finite element model for analysis.

[0152] Specifically, according to the basic principle of calculating the stress distribution of PE unbonded steel strands determined above, the total deformation of the steel strand is averaged according to the total length and elastic modulus to obtain the unit stress variable of the redistributed PE unbonded steel strand. The calculation formula is as follows:

[0153] Δσ PE =ΔL / L×E s (2)

[0154] Where: Δσ PE —Actual stress change of PE unbonded prestressed steel tendons after single deformation load analysis (MPa);

[0155] The difference between the stress variable of each unit of the PE unbonded steel strand and the stress variable of the corresponding unit of the bonded steel strand is the compensation stress load required for the bonded steel strand to be converted into the PE unbonded steel strand. The compensation stress will produce deviations due to the elastic deformation of the concrete if it is directly applied to the model for calculation. Therefore, the compensation stress needs to be corrected. The calculation formula is as follows:

[0156]

[0157] Where: 补偿 —Compensation stress load required for the steel bundle to transform from bonded to PE unbonded (MPa);

[0158] A s —Area of ​​each steel strand (m 2 );

[0159] s p — Distance of steel tendons (m);

[0160] t—thickness of containment (m);

[0161] E c —Elastic modulus of concrete (MPa).

[0162] Reference Figure 4a and Figure 4b ,in Figure 4a and Figure 4b are the stresses of the prestressed tendons of the prestressed concrete containment with and without bonding, respectively. Figure 4a and Figure 4b As shown in the figure, under the accident pressure load, the stress of each steel strand of the unbonded prestressed concrete containment is basically uniform.

[0163] Step 4. Combine the analysis results of bonded prestressed tendons with the compensating stress analysis results to obtain the analysis results of PE unbonded single load.

[0164] Specifically, the analysis results of the bonded prestressed concrete containment under a single load are combined with the analysis results of applying the corrected compensating stress, and the combined result is the analysis result of the PE unbonded prestressed concrete containment under this single load.

[0165] Figure 5 The following is a schematic diagram of the stress of the steel strands of the typical inverted U-shaped prestressed tendons with and without bonded prestressed containment. By post-processing the analysis results of the bonded prestressed containment, the actual theoretical stress value of the unbonded prestressed steel strand under the accident pressure load is 10.95MPa. Figure 5 It can be seen that the steel strand stress of the typical inverted U-shaped prestressed steel strand of the unbonded prestressed containment is basically uniform and very close to the theoretical calculated value.

[0166] Figure 6 The following is a schematic diagram of the stress of the typical horizontal prestressed steel strands with and without bonded prestressed containment. By post-processing the analysis results of the bonded prestressed containment, the actual theoretical stress value of the unbonded prestressed steel strand under the accident pressure load is 33.56MPa. Figure 6 It can be seen that the tendon stress of the typical horizontal prestressed steel tendons of the unbonded prestressed containment is basically uniform and very close to the theoretical calculated value.

[0167] Figure 7 The following is a schematic diagram of the stress of the typical dome horizontal prestressed steel strands with and without bonded prestressed containment. By post-processing the analysis results of the bonded prestressed containment, the actual theoretical stress value of the unbonded prestressed steel strand under the accident pressure load is 18.45MPa. Figure 7 It can be seen that the steel strand stress of the typical dome horizontal prestressed steel strand of the unbonded prestressed containment is basically uniform and very close to the theoretical calculated value.

[0168] It can be understood that, in this embodiment, the actual change value of the unbonded prestress can be calculated by extracting the total deformation of bonding according to the finite element analysis results. Then, the compensation stress (first compensation stress load) is inverted according to the unbonded actual value and the bonded prestress result. The compensation stress is then used as the load input for finite element analysis, and combined with the finite element result of bonded prestress, and finally the finite element result of unbonded prestress (first prestress) is obtained, which should be not much different from the calculated actual value.

[0169] In this embodiment, by determining the distribution principle of PE unbonded steel bundle stress, analyzing the single load of bonded prestressed steel bundles, introducing the compensating stress of PE unbonded steel bundles, and combining the analysis results of bonded prestressed steel bundles with the compensating stress analysis results, compared with the existing stress calculation results of bonded prestressed concrete containment, more accurate analysis results under the action of PE unbonded single load can be obtained.

[0170] Embodiment 3:

[0171] like Figure 8 As shown, the present invention also provides a prestress calculation device for unbonded prestressed concrete containment reinforcement, the device 100 comprising:

[0172] An acquisition module 11 is configured to acquire a first total deformation of a single unbonded steel strand under a preset single load;

[0173] A first obtaining module 12, connected to the obtaining module 11, is configured to obtain a first unit stress variable of the unbonded steel strand according to the first total deformation and the elastic modulus of the steel strand;

[0174] A second obtaining module 13, connected to the first obtaining module 12, is configured to obtain a first compensating stress load required for the bonded steel strand to be transformed into an unbonded steel strand according to the first unit stress variable and the corresponding second unit stress variable of the bonded steel strand;

[0175] The determination module 14 is connected to the second obtaining module 13, and is configured to determine the first prestress of the unbonded steel strand under the preset single load based on the second prestress and the first compensating stress load of the bonded steel strand under the preset single load.

[0176] In some embodiments, the acquisition module 11 is further used to determine the second total deformation of a single bonded steel strand under a preset single load as the first total deformation of a single unbonded steel strand under a preset single load, which specifically includes:

[0177] The second total deformation of the bonded steel strand under a preset single load is calculated according to the following formula (1):

[0178]

[0179] Where, ΔL is the second total deformation of a single bonded steel strand (m); L is the total length of a single steel strand before the load is applied (m); E s is the elastic modulus of the steel strand (MPa); s is the distance between the finite element unit and the starting point of the steel strand (m); Δσ 有粘结is the second unit stress variable of the bonded prestressed steel strand under the preset single load (MPa);

[0180] The second total deformation is determined as the first total deformation of a single unbonded steel strand under a preset single load.

[0181] In some embodiments, the first obtaining module 12 is further used to set that under a preset single load, the stress change of the entire unbonded steel strand is uniform, and the first unit stress variable of the unbonded steel strand is calculated according to the following formula (2):

[0182] Δσ PE =ΔL / L×E s (2)

[0183] Among them, Δσ PE is the first unit stress variable of the unbonded prestressed steel strand (MPa), ΔL is the first total deformation of a single unbonded steel strand (m); L is the total length of a single unbonded steel strand before the load is applied (m); E s is the elastic modulus of the unbonded steel strand (MPa).

[0184] In some embodiments, the second obtaining module 13 is further used to calculate the second compensating stress load required for the unbonded steel strand according to the following formula (3):

[0185] σ 补偿 =Δσ PE -Δσ 有粘结 (3)

[0186] Among them, σ 补偿 The second compensating stress load (MPa) required for the steel strand to transform from a bonded steel strand to an unbonded steel strand;

[0187] The second compensating stress load is corrected according to the following formula (4) to obtain the first compensating stress load required for the bonded steel strand to be transformed into an unbonded steel strand, so as to compensate for the deviation caused by the elastic deformation of the concrete:

[0188]

[0189] in, is the first compensating stress load (MPa) required for the steel strand to transform from a bonded steel strand to an unbonded steel strand; 补偿 A is the second compensating stress load (MPa) required for the steel strand to transform from a bonded steel strand to an unbonded steel strand; s is the area of ​​each strand (m 2 );s p is the distance of the steel strand (m); t is the thickness of the containment (m); Ec is the elastic modulus of concrete (MPa).

[0190] In some embodiments, the determination module 14 is further used to obtain, using finite element software, a second prestress of the bonded steel strands in the bonded prestressed concrete containment under a preset single load, and

[0191] Obtaining a first compensating force of a bonded steel strand in a bonded prestressed concrete containment under a first compensating stress load;

[0192] The second prestressing force and the first compensating force are combined to obtain a first prestressing force of the unbonded steel strands in the unbonded prestressed concrete containment under a preset single load.

[0193] In some embodiments, the apparatus further comprises:

[0194] The combination module is connected to the determination module 14 and is configured to calculate the first stress of the concrete in the unbonded prestressed concrete containment shell according to the determined first prestress of the unbonded steel strand under the preset single load.

[0195] It should be noted that this embodiment is a corresponding device of the prestress calculation method for unbonded prestressed concrete containment reinforcement in the above-mentioned embodiment 1. The method in embodiment 1 can be implemented by adopting this device. The specific implementation method can refer to the description in the prestress calculation method for unbonded prestressed concrete containment reinforcement, and this embodiment will not be repeated here.

[0196] Embodiment 4:

[0197] The present invention also provides a design device for an unbonded prestressed concrete containment shell, comprising:

[0198] The prestress calculation device for unbonded prestressed concrete containment reinforcement as described in Example 3 is used to determine the first prestress of the unbonded steel strand under a preset single load;

[0199] A concrete design module, connected to the prestress calculation device, for combining the first prestress and a preset single load to design the concrete in the unbonded prestressed concrete containment;

[0200] The containment design module is connected to the concrete design module and is used to design the containment according to the concrete.

[0201] In this embodiment, a design device for an unbonded prestressed concrete containment is formed by determining a calculation device for determining the first prestress of the unbonded prestressed concrete containment reinforcement under a preset single load, a concrete design module for designing concrete in the unbonded prestressed concrete containment, and a containment design module for designing the containment based on the designed concrete. The device can accurately simulate the stress changes of the reinforcement in the unbonded prestressed concrete containment in the concrete shell, and design a containment with more accurate concrete stress calculation in the unbonded prestressed concrete containment.

[0202] Embodiment 5:

[0203] This embodiment also provides an unbonded prestressed concrete containment shell, comprising: concrete and a steel bundle consisting of unbonded steel strands,

[0204] The unbonded prestressed concrete containment shell is designed using the setting device described in Example 4.

[0205] In this embodiment, the unbonded prestressed concrete containment shell designed by adopting the setting device described in Example 4 can accurately simulate the stress changes of the reinforcement in the concrete shell of the unbonded prestressed concrete containment shell, and the concrete stress calculation in the designed unbonded prestressed concrete containment shell is more accurate.

[0206] It should be clear that the present application is not limited to the specific configuration and processing described above and shown in the figures. For the sake of simplicity, a detailed description of the known method is omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of the present application is not limited to the specific steps described and shown, and those skilled in the art can make various changes, modifications and additions, or change the order between the steps after understanding the spirit of the present application.

[0207] The functional blocks shown in the above block diagram can be implemented as hardware, software, firmware or a combination thereof. When implemented in hardware, it can be, for example, an electronic circuit, an application specific integrated circuit (ASIC), appropriate firmware, a plug-in, a function card, etc. When implemented in software, the elements of the present application are programs or code segments that are used to perform the required tasks. The program or code segment can be stored in a machine-readable medium, or transmitted on a transmission medium or a communication link by a data signal carried in a carrier wave. "Machine-readable medium" can include any medium capable of storing or transmitting information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, ROM, flash memory, erasable ROM (EROM), floppy disks, CD-ROMs, optical disks, hard disks, optical fiber media, radio frequency (RF) links, etc. The code segment can be downloaded via a computer network such as the Internet, an intranet, etc.

[0208] The above are only specific implementation methods of the present application. Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the systems, modules and units described above can refer to the corresponding processes in the aforementioned method embodiments, and will not be repeated here. It should be understood that the protection scope of the present application is not limited to this. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in this application, and these modifications or replacements should be included in the protection scope of this application.

Claims

1. A method for calculating the prestress of unbonded prestressed concrete containment reinforcement, characterized in that: include: Obtaining a first total deformation of a single unbonded steel strand under a preset single load; According to the first total deformation and the elastic modulus of the steel strand, a first unit stress variable of the unbonded steel strand is obtained; According to the first unit stress variable and the corresponding second unit stress variable of the bonded steel strand, a first compensating stress load required for the bonded steel strand to be transformed into an unbonded steel strand is obtained; The first prestress of the unbonded steel strand under the preset single load is determined based on the second prestress of the bonded steel strand under the preset single load and the first compensating stress load.

2. The method for calculating the prestress of the unbonded prestressed concrete containment reinforcement according to claim 1, characterized in that: The method of obtaining the total deformation of a single steel strand under a preset single load includes: The second total deformation of a single bonded steel strand under a preset single load is determined as the first total deformation of a single unbonded steel strand under a preset single load, which specifically includes: The second total deformation of the bonded steel strand under a preset single load is calculated according to the following formula (1): Where, ΔL is the second total deformation of a single bonded steel strand (m); L is the total length of a single steel strand before the load is applied (m); E s is the elastic modulus of the steel strand (MPa); s is the distance between the finite element unit and the starting point of the steel strand (m); Δσ 有粘结 is the second unit stress variable of the bonded prestressed steel strand under the preset single load (MPa); The second total deformation is determined as the first total deformation of a single unbonded steel strand under a preset single load.

3. The method for calculating the prestress of the unbonded prestressed concrete containment reinforcement according to claim 2, characterized in that: The step of calculating the first unit stress variable of the unbonded steel strand according to the first total deformation and the elastic modulus of the steel strand comprises: Assuming that the stress change of the entire unbonded steel strand is uniform under the action of a preset single load, the first unit stress variable of the unbonded steel strand is calculated according to the following formula (2): Board PE =ΔL / L×E s (2) Among them, Δσ PE is the first unit stress variable of the unbonded prestressed steel strand (MPa), ΔL is the first total deformation of a single unbonded steel strand (m); L is the total length of a single unbonded steel strand before the load is applied (m); E s is the elastic modulus of the unbonded steel strand (MPa).

4. The method for calculating the prestress of the unbonded prestressed concrete containment reinforcement according to any one of claims 1 to 3, characterized in that: The step of calculating the first compensating stress load required for converting the bonded steel strand into the unbonded steel strand according to the first unit stress variable and the corresponding second unit stress variable of the bonded steel strand specifically includes: The second compensating stress load required for the unbonded steel strand is calculated according to the following formula (3): s 补偿 =Ds PE -Board 有粘结 (3) Among them, σ 补偿 The second compensating stress load (MPa) required for the steel strand to transform from a bonded steel strand to an unbonded steel strand; The second compensating stress load is corrected according to the following formula (4) to obtain the first compensating stress load required for the bonded steel strand to be transformed into an unbonded steel strand, so as to compensate for the deviation caused by the elastic deformation of the concrete: in, is the first compensating stress load (MPa) required for the steel strand to transform from a bonded steel strand to an unbonded steel strand; 补偿 A is the second compensating stress load (MPa) required for the steel strand to transform from a bonded steel strand to an unbonded steel strand; s is the area of ​​each strand (m 2 );s p is the distance of the steel strand (m); t is the thickness of the containment (m); E c is the elastic modulus of concrete (MPa).

5. The method for calculating the prestress of the unbonded prestressed concrete containment reinforcement according to claim 1, characterized in that: The method of determining the first prestress of the unbonded steel strand under the preset single load according to the second prestress of the bonded steel strand under the preset single load and the first compensating stress load comprises: Using finite element software, the second prestress of the bonded steel strands in the bonded prestressed concrete containment under the action of a preset single load is obtained, and Obtaining a first compensating force of a bonded steel strand in a bonded prestressed concrete containment under a first compensating stress load; The second prestressing force and the first compensating force are combined to obtain a first prestressing force of the unbonded steel strands in the unbonded prestressed concrete containment under a preset single load.

6. The method for calculating the prestress of the unbonded prestressed concrete containment reinforcement according to any one of claims 1 to 5, characterized in that: The method further comprises: The first stress of concrete in the unbonded prestressed concrete containment is calculated based on the determined first prestress of the unbonded steel strands under the action of a preset single load.

7. A prestress calculation device for unbonded prestressed concrete containment reinforcement, characterized in that: The device comprises: An acquisition module, which is configured to acquire a first total deformation of a single unbonded steel strand under a preset single load; A first obtaining module, connected to the acquisition module, is configured to obtain a first unit stress variable of the unbonded steel strand according to the first total deformation and the elastic modulus of the steel strand; A second obtaining module, connected to the first obtaining module, is configured to obtain a first compensating stress load required for converting the bonded steel strand into the unbonded steel strand based on the first unit stress variable and the corresponding second unit stress variable of the bonded steel strand; The determination module is connected to the second obtaining module, and is configured to determine the first prestress of the unbonded steel strand under the preset single load based on the second prestress of the bonded steel strand under the preset single load and the first compensating stress load.

8. The prestress calculation device for unbonded prestressed concrete containment reinforcement according to claim 7, characterized in that: The second module is also used The second compensating stress load required for the unbonded steel strand is calculated according to the following formula (3): s 补偿 =Ds PE -Board 有粘结 (3) Among them, σ 补偿 The second compensating stress load (MPa) required for the steel strand to transform from a bonded steel strand to an unbonded steel strand; The second compensating stress load is corrected according to the following formula (4) to obtain the first compensating stress load required for the bonded steel strand to be transformed into an unbonded steel strand, so as to compensate for the deviation caused by the elastic deformation of the concrete: in, is the first compensating stress load (MPa) required for the steel strand to transform from a bonded steel strand to an unbonded steel strand; 补偿 A is the second compensating stress load (MPa) required for the steel strand to transform from a bonded steel strand to an unbonded steel strand; s is the area of ​​each strand (m 2 );s p is the distance of the steel strand (m); t is the thickness of the containment (m); E c is the elastic modulus of concrete (MPa).

9. A design device for an unbonded prestressed concrete containment, characterized in that: include: The prestress calculation device for unbonded prestressed concrete containment reinforcement according to any one of claims 7 to 8, used to determine the first prestress of the unbonded steel strand under a preset single load; A concrete design module, connected to the prestress calculation device, for combining the first prestress and a preset single load to design the concrete in the unbonded prestressed concrete containment; The containment design module is connected to the concrete design module and is used to design the containment according to the concrete.

10. An unbonded prestressed concrete containment shell, characterized in that: include: concrete and steel strands consisting of unbonded steel strands, The unbonded prestressed concrete containment shell is designed using the setting device as described in claim 9.

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