Method for calculating contraction deformation of steel reinforced concrete based on hindering effect of profile steel on concrete humidity transfer

Abstract

The invention discloses a steel reinforced concrete shrinkage deformation calculation method based on the hindering effect of profile steel on concrete humidity transfer, and belongs to the technical field of concrete. In order to solve the problem that the contraction deformation of the steel reinforced concrete cannot be accurately predicted in the prior art, the invention provides an improved calculation method for the contraction deformation of the steel reinforced concrete. And performing shrinkage weighting on the section steel and non-section steel areas to obtain the overall shrinkage deformation of the steel reinforced concrete. According to the method, the influence area is divided, the shrinkage model is corrected through the shortest moisture transfer path, the profile steel inhibition coefficient is proposed to quantitatively describe the profile steel limiting effect, and accurate prediction of shrinkage of concrete in different profile steel forms is achieved. The method is suitable for the engineering fields of high-rise buildings, large-span structures and the like adopting steel reinforced concrete structures.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of concrete structure performance analysis, and particularly relates to a steel reinforced concrete shrinkage deformation prediction technology in which the obstructive effect of steel on concrete humidity transfer is introduced in shrinkage calculation. BACKGROUND

[0002] Steel reinforced concrete has the advantages of high bearing capacity, strong toughness, excellent seismic performance and the like, and is an optimal form for high-rise and large-span structures. With the expansion of urban building scale and the improvement of structural performance requirements, the application of steel reinforced concrete structures is increasingly widespread, and higher requirements are put forward for long-term deformation control thereof.

[0003] Concrete inevitably produces volume shrinkage in the process of setting and hardening, which is affected by the material properties and environmental conditions. Due to the existence of elements such as embedded steel bars, studs or steel bars in the structure that limit the free deformation of the components, the concrete shrinkage often causes additional stress accumulation, leading to structural diseases such as cracking and steel bar yielding. Therefore, accurately grasping the evolution law of concrete shrinkage deformation is of great importance to the performance guarantee of the structure during construction and service period.

[0004] Traditional concrete shrinkage prediction models, such as the shrinkage formula based on BS EN 1992 specification, are mainly applicable to ordinary concrete. Such models assume that the humidity transfer path of concrete is not significantly obstructed, and cannot reflect the significant differences caused by the closing and shielding effect of steel web and wing plate on humidity transfer path in steel reinforced concrete.

[0005] In steel reinforced concrete, the steel component surrounds the internal concrete part, making the water migration path longer, resulting in significant differences in drying speed and shrinkage deformation in different regions. This state of partially closed steel is different from fully exposed reinforced concrete and fully sealed steel pipe concrete, and there is currently no applicable model to effectively predict such structures, which seriously restricts the design reliability and engineering promotion of steel reinforced concrete. Therefore, there is an urgent need for a new shrinkage deformation calculation method that can accurately depict the obstructive effect of steel on humidity transfer, to meet the engineering application requirements of steel reinforced concrete structures. SUMMARY

[0006] In order to solve the problem that the existing technology cannot accurately predict the shrinkage deformation of steel reinforced concrete, an improved steel reinforced concrete shrinkage deformation calculation method is proposed, which considers the obstructive effect of steel on concrete humidity transfer, modifies the traditional model by replacing the nominal size and introducing the steel influence zone and suppression coefficient, and improves the prediction accuracy. The specific scheme is as follows: A steel reinforced concrete shrinkage deformation calculation method based on the obstructive effect of steel on concrete humidity transfer, the method comprising: S1, collecting steel reinforced concrete parameters; S2, dividing the concrete section into a steel influencing zone and a non-steel influencing zone based on the parameters, the steel influencing zone being any one of an H-shaped steel influencing zone, a double-H-shaped steel influencing zone, and a partially closed steel influencing zone, the partially closed steel influencing zone being composed of a fully closed influencing zone and a semi-closed influencing zone; S3, calculating the area of the steel influencing zone; S4, based on the area of the steel influencing zone, calculating the shortest distance from the center of gravity of the steel influencing zone to the edge of the steel-concrete section when considering the hindering effect of the steel on the humidity transfer of the concrete; S5, based on the area of the steel influencing zone, calculating the shortest distance from the center of gravity of the steel influencing zone to the edge of the steel-concrete section when not considering the hindering effect of the steel on the humidity transfer of the concrete; S6, obtaining the concrete shrinkage deformation of the non-steel influencing zone through a concrete shrinkage calculation model; S7, replacing the nominal size in the concrete shrinkage calculation model with the shortest distance described in S4, to obtain the concrete shrinkage deformation of the steel influencing zone when considering the hindering effect of the steel on the humidity transfer of the concrete; S8, replacing the nominal size in the concrete shrinkage calculation model with the shortest distance described in S5, to obtain the concrete shrinkage deformation of the steel influencing zone when not considering the hindering effect of the steel on the humidity transfer of the concrete; S9, obtaining the restraint coefficient of the steel influencing zone according to the concrete shrinkage deformations described in S7 and S8; S10, based on the restraint coefficient of the steel influencing zone, weighting and calculating the concrete shrinkage deformations of the steel influencing zone and the non-steel influencing zone according to the area ratio, to obtain the overall steel-concrete shrinkage deformation.

[0007] Further, the method for calculating the area of the steel influencing zone in S3 is: The area of the H-shaped steel influencing zone : , The area of the double-H-shaped steel influencing zone : , The area of the fully closed influencing zone : , The area of the semi-closed influencing zone : , wherein, is the height of the H-shaped steel, is the wing plate thickness of the H-shaped steel, is the wing plate width of the H-shaped steel, This refers to the web thickness of the H-beam. The height of the double H-beam. The thickness of the flange of the double H-beam. The width of the flange of the double H-beam. This refers to the web thickness of a double H-beam. The height of the partially enclosed steel section. This refers to the width of the flange of a partially closed steel section. This refers to the web thickness of partially closed steel sections. This refers to the web spacing of partially closed steel sections.

[0008] Furthermore, in S4, the method for calculating the shortest distance from the centroid of the steel section's influence zone to the edge of the steel-concrete cross-section, considering the steel's obstruction of moisture transfer to concrete, is as follows: The shortest distance from the centroid of the H-beam's influence zone to the edge of the steel-concrete cross-section. : , The shortest distance from the centroid of the influence zone of the double H-beam to the edge of the steel-concrete section : , The shortest distance from the center of gravity of the fully enclosed affected area to the edge of the steel-concrete cross-section : , The shortest distance from the centroid of the semi-enclosed influence zone to the edge of the steel-concrete cross-section : , in, Let be the distance from the centroid of the H-beam's affected zone to its right-angled side. This is the distance from the centroid of the H-beam's affected area to its top edge. The thickness of the protective layer for H-beams. The distance from the centroid of the affected area of ​​the double H-beam to its right-angled side is given. The distance from the centroid of the affected area of ​​the double H-beam to its upper bottom edge. The thickness of the protective layer for double H-beams. It is the distance from the centroid of the semi-enclosed influence zone to its right-angled side. It is the distance from the center of gravity of the semi-enclosed influence zone to its upper bottom edge. For the thickness of partially closed steel wing plates, This refers to the thickness of the protective layer for partially enclosed steel sections.

[0009] Furthermore, in S5, the method for calculating the shortest distance from the centroid of the steel section's influence zone to the edge of the steel-concrete cross-section, without considering the steel section's obstruction of moisture transfer to concrete, is as follows: The shortest distance from the centroid of the H-beam's influence zone to the edge of the steel-concrete cross-section. : , The shortest distance from the centroid of the influence zone of the double H-beam to the edge of the steel-concrete section : , The shortest distance from the centroid of the semi-enclosed influence zone to the edge of the steel-concrete cross-section : .

[0010] Furthermore, in S7, the method for determining the concrete shrinkage deformation in the steel-affected zone when considering the obstruction of moisture transfer to concrete is as follows: Concrete shrinkage deformation in the H-beam influence zone : , Concrete shrinkage deformation in the influence zone of double H-beams : , Concrete shrinkage deformation in the fully enclosed influence zone : , Concrete shrinkage deformation in the semi-enclosed influence zone : , in, For self-generated shrinkage deformation, To account for the hindering effect of steel sections on the moisture transfer of concrete, the drying shrinkage deformation of the concrete in the H-section's influence zone is considered. To account for the hindering effect of steel sections on the moisture transfer of concrete, the drying shrinkage deformation of the concrete in the affected zone of the double H-section steel section is considered. To account for the obstruction of moisture transfer to concrete by the steel profiles, the drying shrinkage deformation of the concrete in the fully enclosed affected zone is considered. When considering the obstruction of moisture transfer to concrete by the steel profile, the drying shrinkage deformation of the concrete in the semi-enclosed influence zone is taken into account.

[0011] Furthermore, in S8, the method for obtaining the concrete shrinkage deformation in the steel-affected zone without considering the obstruction of moisture transfer to concrete is as follows: Concrete shrinkage deformation in the H-beam influence zone : , Concrete shrinkage deformation in the influence zone of double H-beams : , Concrete shrinkage deformation in the semi-enclosed influence zone : , in, To account for the drying shrinkage deformation of concrete in the H-beam's influence zone without considering the obstruction of moisture transfer to concrete by the steel section, To account for the drying shrinkage deformation of concrete in the affected zone of the double H-beam without considering the obstruction of moisture transfer to the concrete by the steel section, This refers to the drying shrinkage deformation of concrete in the semi-enclosed influence zone without considering the obstruction of moisture transfer by the steel profile.

[0012] Furthermore, the method for obtaining the inhibition coefficient of the steel section influence zone in S9 is as follows: The damping coefficient of the H-beam's influence zone. ; The damping coefficient of the affected zone of the double H-beam. ; The damping coefficient of the steel profile in the fully enclosed influence zone ; The damping coefficient of the steel profile in the semi-enclosed influence zone. .

[0013] Furthermore, the method for obtaining the integral steel-concrete composite shrinkage deformation in S10 is as follows: , , in, The area of ​​the concrete cross-section. The length of the steel-concrete composite section, The width of the steel-concrete composite section. This is due to the shrinkage deformation of the integral steel-concrete composite structure. This refers to the shrinkage deformation of concrete in the non-steel-affected zone.

[0014] Based on the same inventive concept, the present invention also proposes a computer storage medium for storing a computer program, wherein when the computer program is read by a computer, the computer executes any of the methods described in the present invention.

[0015] Based on the same inventive concept, the present invention also proposes a computer program product, which, when read, implements the method described in any one of the present invention.

[0016] Compared with the prior art, the present invention has the following beneficial effects: The method for calculating shrinkage deformation of steel-concrete composite as described in this invention divides the concrete cross-section into steel-influenced and non-steel-influenced zones, and distinguishes between H-beam influence zones, double H-beam influence zones, and partially closed steel-influenced zones composed of fully enclosed and semi-enclosed influence zones. This allows for the partitioning of humidity transmission paths and shrinkage characteristics in different areas, overcoming the shortcomings of existing technologies that treat steel-concrete composite cross-sections as homogeneous concrete and fail to reflect the actual impact of steel on the humidity and shrinkage fields.

[0017] The method for calculating shrinkage deformation of steel-concrete composite sections described in this invention calculates the shortest distance from the centroid of the steel-influenced zone to the edge of the steel-concrete composite section, considering and not considering the obstruction of moisture transmission by the steel, based on the area of ​​the steel-influenced zone. This distance is used as a nominal dimension substitute in the shrinkage model, strictly linking the nominal dimension to the specific steel arrangement and cross-sectional geometry. This quantifies the shrinkage deformation of steel-concrete composite sections considering the obstruction of moisture transmission by the steel. Unlike existing technologies that directly use a uniform nominal dimension of the component cross-section to calculate shrinkage, this invention can precisely characterize the differences in the length of the moisture transmission path, thereby improving the physical rationality and accuracy of the shrinkage calculation.

[0018] The method for calculating shrinkage deformation of steel-concrete composite sections described in this invention provides analytical expressions for the area and centroid position of the influence zone of H-beams, double H-beams, and partially closed steel sections within the same calculation framework. It clarifies the area division and geometric parameter relationships between fully and semi-closed influence zones, achieving a unified description of three typical steel-concrete composite sections. Compared to existing technologies that establish separate models for each steel section type, making them difficult to generalize in engineering, this invention's method has good versatility and scalability, facilitating smooth migration and engineering promotion between different steel section arrangements.

[0019] The method for calculating shrinkage deformation of steel-concrete composite as described in this invention introduces the autogenous shrinkage and drying shrinkage models from the BS EN1992 European standard into the concrete shrinkage calculation. It combines standard parameters such as the time function of autogenous shrinkage development, the time function of drying shrinkage development, and the relative humidity influence coefficient with the equivalent nominal dimensions proposed in this invention. By substituting different nominal dimensions into the steel-affected area and the non-steel-affected area respectively for calculation, and then weighting and superimposing them according to the area ratio, this invention not only inherits the engineering acceptance of the standard model, but also overcomes the limitation of the standard not considering the humidity barrier effect of steel, realizing an engineering-friendly algorithm that can make local corrections within the standard framework.

[0020] The method for calculating shrinkage deformation of steel-concrete composite structures described in this invention constructs a steel inhibition coefficient by separately calculating the shrinkage deformation of each steel section's influence zone, considering and not considering the hindering effect of moisture transmission from the steel. Compared with existing techniques that rely solely on empirical reduction coefficients to correct shrinkage overall and struggle to differentiate the degree of influence of different steel sections, this invention can quantitatively compare the ability of different steel section layout schemes to inhibit shrinkage deformation, providing a more intuitive evaluation index for steel section layout optimization and cross-sectional design.

[0021] The method for calculating the shrinkage deformation of steel-concrete composite structures described in this invention, after obtaining the concrete shrinkage deformation and corresponding suppression coefficients in each steel-affected and non-steel-affected zone, weights the results based on the cross-sectional area ratio to establish overall shrinkage calculation expressions for H-sections, double H-sections, and partially closed steel sections, forming a set of overall shrinkage solution methods covering various steel composite sections. Compared to existing technologies that treat the equivalent homogeneous section and uniform shrinkage value, leading to significant deviations in predicting component deflection, prestress loss, and cracking, this invention can significantly improve the accuracy of long-term deformation and crack control calculations for steel-concrete composite structures, providing more accurate data for structural durability and service performance evaluation.

[0022] The method for calculating shrinkage deformation of steel-concrete composite profiles described in this invention provides unified definitions for various geometric parameters, nominal dimensions, correlation coefficients of autogenous shrinkage and drying shrinkage, and environmental relative humidity. It also provides rules for the coefficient values ​​related to cement type, making it suitable for direct implementation in numerical programs or design software. Compared to existing models with scattered formulas, unclear parameter meanings, and difficulties in coding implementation, the method of this invention features complete parameter definitions and a clear logical structure, facilitating the formation of standardized calculation processes and meeting the practical application needs of engineering design units and research institutions for refined calculation of steel-concrete composite shrinkage.

[0023] This invention features wide applicability and high calculation accuracy. It can fully consider the hindering effect of built-in steel on the moisture transfer of concrete and accurately predict the shrinkage deformation of steel-concrete composite members. It is applicable to engineering fields such as high-rise buildings and large-span structures that use steel-concrete composite structures. Attached Figure Description

[0024] Figure 1 This is a flowchart of the method for calculating the shrinkage deformation of steel-concrete composite structures as described in the implementation method; Figure 2 This is a schematic diagram of the H-beam's affected area and moisture transfer distance as described in the implementation method; Figure 3 This is a schematic diagram of the affected area and moisture transfer distance of the double H-beam as described in the implementation method; Figure 4 This is a schematic diagram of the partially enclosed steel profile's affected area and moisture transfer distance as described in the implementation method; Detailed Implementation The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] Implementation Method 1 A method for calculating the shrinkage deformation of steel-concrete composite structures based on the effect of steel sections hindering moisture transfer in concrete, the method comprising: S1. Collect parameters of the steel-concrete composite structure, including material parameters, component dimensions, and environmental parameters. Further, the material parameters include the standard value of the 28-day cylindrical compressive strength of the concrete and the type of cement (early-strength cement). R Ordinary cement N Slow-hardening cement S The component dimensions include the height of the steel section, the width of the flange of the steel section, the thickness of the flange of the steel section, the thickness of the web of the steel section, the concrete cross-sectional dimensions, and the thickness of the protective layer of the steel section. If it is a semi-enclosed steel section, the web spacing also needs to be collected. The environmental parameters include the average ambient humidity. S2. Based on the parameters, the concrete section is divided into a steel-influenced zone and a non-steel-influenced zone. The steel-influenced zone is any one of the H-beam influence zone, double H-beam influence zone, and partially closed steel-influenced zone. The partially closed steel-influenced zone consists of a fully closed influence zone and a semi-closed influence zone. The concrete section division method is applicable to H-beams, double H-beams, and partially closed steels with clearly defined web spacing used in conventional engineering. The connection method between the flange and the web and the cross-sectional topology can ensure that the diagonal and the edge structure have a unique intersection point, thus making the division method applicable to the conventional steel size range of engineering. S3, Calculate the area of ​​the affected zone of the steel section; S4. Based on the area of ​​the steel section's influence zone, calculate the shortest distance from the centroid of the steel section's influence zone to the edge of the steel-concrete cross section, considering the steel section's obstruction of moisture transfer to the concrete. S5. Based on the area of ​​the steel section's influence zone, calculate the shortest distance from the centroid of the steel section's influence zone to the edge of the steel-concrete cross section, without considering the steel section's obstruction of moisture transfer to the concrete. S6. Using the concrete shrinkage calculation model, obtain the concrete shrinkage deformation in the non-steel-affected zone; S7. Replace the nominal dimension in the concrete shrinkage calculation model with the shortest distance described in S4 to obtain the concrete shrinkage deformation in the steel-affected zone when considering the obstruction of concrete moisture transmission by the steel section. S8. Replace the nominal dimension in the concrete shrinkage calculation model with the shortest distance mentioned in S5 to obtain the concrete shrinkage deformation in the steel-affected zone when the obstruction of the steel section on the moisture transfer of the concrete is not considered. S9. Based on the concrete shrinkage deformation described in S7 and S8, obtain the inhibition coefficient of the steel-affected zone. S10. Based on the inhibition coefficient of the steel section influence zone, the concrete shrinkage deformation of the steel section influence zone and the non-steel section influence zone is weighted according to the area ratio to obtain the overall steel section concrete shrinkage deformation.

[0026] Furthermore, the method for calculating the area of ​​the steel section's influence zone in S3 is as follows: Area of ​​the H-beam's affected zone : , , , , Area of ​​the affected zone of double H-beams : , , , , Area of ​​the fully enclosed impact zone : , Area of ​​the semi-enclosed influence zone : , , , , in, This refers to the length of the top edge of the H-beam's affected area. This is the length of the bottom edge of the H-beam's affected area. The height of the H-beam's affected zone. The height of the H-beam. The thickness of the flange of the H-beam. The width of the flange of the H-beam. This refers to the web thickness of the H-beam. The length of the top edge of the affected area of ​​the double H-beam. This refers to the length of the bottom edge of the affected area of ​​the double H-beam. The height of the affected area of ​​the double H-beam. The height of the double H-beam. The thickness of the flange of the double H-beam. The width of the flange of the double H-beam. This refers to the web thickness of a double H-beam. This is the length of the upper bottom edge of the semi-enclosed influence zone. This is the length of the bottom edge of the semi-enclosed influence zone. The height of the semi-enclosed influence zone. The height of the partially enclosed steel section. This refers to the width of the flange of a partially closed steel section. This refers to the web thickness of partially closed steel sections. This refers to the web spacing of partially closed steel sections.

[0027] By establishing analytical area formulas for the H-beam influence zone, double H-beam influence zone, fully enclosed influence zone, and semi-enclosed influence zone respectively, this implementation method ensures that the geometric quantity of the influence zone under different steel arrangement conditions can be directly and accurately calculated from the component size, avoiding the deviation caused by traditional reliance on experience estimation or manual zoning.

[0028] Furthermore, in S4, the method for calculating the shortest distance from the centroid of the steel section's influence zone to the edge of the steel-concrete cross-section, considering the steel's obstruction of moisture transfer to concrete, is as follows: The shortest distance from the centroid of the H-beam's influence zone to the edge of the steel-concrete cross-section. : , , , The shortest distance from the centroid of the influence zone of the double H-beam to the edge of the steel-concrete section : , , , The shortest distance from the center of gravity of the fully enclosed affected area to the edge of the steel-concrete cross-section : The fully enclosed affected area is completely surrounded by the web and flanges. There is no moisture exchange path between the concrete inside and the external environment. Therefore, its equivalent moisture transfer distance can be considered infinite. , The shortest distance from the centroid of the semi-enclosed influence zone to the edge of the steel-concrete cross-section : , , , in, Let be the distance from the centroid of the H-beam's affected zone to its right-angled side. This is the distance from the centroid of the H-beam's affected area to its top edge. The thickness of the protective layer for H-beams. The distance from the centroid of the affected area of ​​the double H-beam to its right-angled side is given. The distance from the centroid of the affected area of ​​the double H-beam to its upper bottom edge. The thickness of the protective layer for double H-beams. It is the distance from the centroid of the semi-enclosed influence zone to its right-angled side. It is the distance from the center of gravity of the semi-enclosed influence zone to its upper bottom edge. For the thickness of partially closed steel wing plates, This refers to the thickness of the protective layer for partially enclosed steel sections.

[0029] By establishing formulas for the shortest humidity transfer path from the center of gravity to the edge of the section for H-beams, double H-beams, and semi-enclosed influence zones, and naturally treating the path of the fully enclosed influence zone as infinite, this implementation method achieves zoned modeling of the actual restricted situation of humidity transfer through the concrete medium. This implementation method can accurately reflect the degree of obstruction of humidity diffusion by the steel section, so that the nominal size when substituted into the shrinkage model matches the actual humidity diffusion conditions, thereby significantly improving the authenticity of the shrinkage deformation calculation results.

[0030] Furthermore, in S5, the method for calculating the shortest distance from the centroid of the steel section's influence zone to the edge of the steel-concrete cross-section, without considering the steel section's obstruction of moisture transfer to concrete, is as follows: The shortest distance from the centroid of the H-beam's influence zone to the edge of the steel-concrete cross-section. : , The shortest distance from the centroid of the influence zone of the double H-beam to the edge of the steel-concrete section : , The shortest distance from the centroid of the semi-enclosed influence zone to the edge of the steel-concrete cross-section : .

[0031] By calculating the shortest humidity transfer distance for H-beams, double H-beams, and semi-enclosed affected areas under conditions without considering obstruction, this invention constructs a control path length for free humidity diffusion. This path serves as a unified nominal dimension in the BS EN 1992 shrinkage model, allowing the difference in the same affected area under conditions considering and without obstruction to be quantified, facilitating comparison of the humidity suppression effects of different steel configurations in engineering projects.

[0032] Furthermore, in S7, the method for determining the concrete shrinkage deformation in the steel-affected zone when considering the obstruction of moisture transfer to concrete is as follows: Concrete shrinkage deformation in the H-beam influence zone : , , , , , , , , , , Concrete shrinkage deformation in the influence zone of double H-beams : , , , , , , , , , , Concrete shrinkage deformation in the fully enclosed influence zone : , , , , , , , , , , Concrete shrinkage deformation in the semi-enclosed influence zone : , , , , , , , , , , This implementation method follows the European standard BS EN 1992. The recommended approach is to use discrete values, i.e., based on the nominal size. h 0 is used for linear interpolation, and the result is not greater than 1.

[0033] in, For self-generated shrinkage deformation, To account for the hindering effect of steel sections on the moisture transfer of concrete, the drying shrinkage deformation of the concrete in the H-section's influence zone is considered. To account for the hindering effect of steel sections on the moisture transfer of concrete, the drying shrinkage deformation of the concrete in the affected zone of the double H-section steel section is considered. To account for the obstruction of moisture transfer to concrete by the steel profiles, the drying shrinkage deformation of the concrete in the fully enclosed affected zone is considered. When considering the obstruction of moisture transfer to concrete by the steel profile, the drying shrinkage deformation of the concrete in the semi-enclosed influence zone is taken into account. For the time function of autogenous contraction development. In the implementation method, the drying shrinkage development of each type of steel-concrete composite is a time function. The relative humidity influence coefficient. This refers to the standard value of the 28-day compressive strength of concrete cylinders. For the calculated age, This refers to the age at which concrete begins to dry and shrink, typically at the end of the initial setting phase, and is generally taken as 1. As per the BS EN 1992 European standard, depending on coefficient, Nominal size, ; It depends on the type of cement, which is a coefficient. S hour, The type of cement is N hour, The type of cement is R hour, , It also depends on the coefficient of the cement type, where the cement type is... S hour, The type of cement is N hour, The type of cement is R hour, , RH For ambient relative humidity, .

[0034] By introducing a nominal size representing the humidity transfer constraint in the self-generated shrinkage and drying shrinkage models The shrinkage deformation was calculated for H-beams, double H-beams, fully enclosed areas, and semi-enclosed areas respectively, ensuring that the differences in humidity fields in different affected areas under the consideration of obstruction are reflected in the shrinkage amount. This implementation method realizes the dual coupling of the differences in the geometric layout of the steel section and the differences in the humidity diffusion path, so that the model exhibits higher accuracy in long-term deformation analysis.

[0035] Furthermore, in S8, the method for obtaining the concrete shrinkage deformation in the steel-affected zone without considering the obstruction of moisture transfer to concrete is as follows: Concrete shrinkage deformation in the H-beam influence zone : , , , , , , , , , , Concrete shrinkage deformation in the influence zone of double H-beams : , , , , , , , , , , Concrete shrinkage deformation in the fully enclosed affected area: when At that time, the time function of its drying shrinkage development approaches zero infinitely, which is consistent with the physical characteristic that the humidity of concrete inside a fully enclosed area does not change.

[0036] Concrete shrinkage deformation in the semi-enclosed influence zone : , , , , , , , , , , in, To account for the drying shrinkage deformation of concrete in the H-beam's influence zone without considering the obstruction of moisture transfer to concrete by the steel section, To account for the drying shrinkage deformation of concrete in the affected zone of the double H-beam without considering the obstruction of moisture transfer to the concrete by the steel section, This refers to the drying shrinkage deformation of concrete in the semi-enclosed influence zone without considering the obstruction of moisture transfer by the steel profile.

[0037] By using the shortest path under free humidity diffusion conditions as the nominal size, the shrinkage deformation of each affected area under unobstructed conditions was calculated, and a set of benchmark shrinkage amounts was constructed to compare with the results considering obstruction. This implementation method not only allows the inhibition effect to be presented in specific numerical values, but also provides a quantifiable reference value for subsequent overall weighting, thereby avoiding the arbitrariness of using empirical reduction coefficients in the prior art and improving the scientificity and verifiability of the shrinkage inhibition ability evaluation.

[0038] Furthermore, the method for obtaining the inhibition coefficient of the steel section influence zone in S9 is as follows: The damping coefficient of the H-beam's influence zone. ; The damping coefficient of the affected zone of the double H-beam. ; The damping coefficient of the steel profile in the fully enclosed influence zone ; The damping coefficient of the steel profile in the semi-enclosed influence zone. .

[0039] Since there is no humidity exchange path in the fully enclosed affected area, there is no calculable baseline shrinkage amount under the condition of "not considering the obstruction effect". This implementation method uses the shrinkage deformation of the non-steel affected area as a reference value to construct its inhibition coefficient, which is more in line with the physical meaning.

[0040] Based on the calculation results considering both obstruction and non-obstruction, the inhibition coefficients of H-beams, double H-beams, fully enclosed zones, and semi-enclosed zones are constructed, so that the inhibition effect is presented in a deterministic parameter form. This implementation method can eliminate the interference of different cross-sectional dimensions and humidity conditions on the absolute shrinkage, and allow the influence of the humidity transmission obstruction effect of the steel section to be independently characterized. The advantage of this implementation method is that the introduction of inhibition coefficients makes the entire calculation process more explicit.

[0041] Furthermore, the method for obtaining the integral steel-concrete composite shrinkage deformation in S10 is as follows: , , The above three types of overall shrinkage calculation expressions are mutually exclusive. That is, the corresponding formula should be selected according to the actual form of the built-in steel used in the concrete section, rather than being substituted into them at the same time. in, The area of ​​the concrete cross-section. This is due to the shrinkage deformation of the integral steel-concrete composite structure. This refers to the shrinkage deformation of concrete in the non-steel-affected zone.

[0042] By weighting the shrinkage deformation of each affected zone according to the area ratio and combining it with the inhibition coefficient, an overall shrinkage deformation calculation model applicable to H-beams, double H-beams and partially closed steel sections is constructed. This implementation method quantifies the relationship between the local humidity-restricted area and the overall section deformation, realizing a complete calculation chain from the subdivision of the affected zone to the overall component performance, and can more accurately predict the long-term deformation and crack development behavior of steel-concrete composite members.

[0043] To avoid ambiguity, the upper bottom edge, lower bottom edge, and inclined edge described in this embodiment are all based on the unique intersection of the inner edge of the steel flange, the outer edge of the web, and the diagonal of the section. The above geometric point exists uniquely in any steel section, thereby ensuring the structural uniqueness of the trapezoid in the influence zone.

[0044] Implementation Method 2 This embodiment combines the technical solutions described in the foregoing embodiments, and, in conjunction with actual application scenarios and the usage process of computer program products that implement the method of this invention, further verifies and explains the technical effects of this invention through specific examples.

[0045] like Figure 1 The flowchart shown illustrates a method for calculating the shrinkage deformation of steel-concrete composite structures based on the hindering effect of steel sections on the moisture transfer of concrete. The method includes the following steps: Step 1: Collect parameters of steel-concrete composite structures, including: Step 11: Collect material parameters, including the standard value of the 28-day compressive strength of concrete cylinders. and types of cement, including high-early-strength cement. Ordinary cement and slow-hardening cement ; Step 12: Collect component dimensions, including the type of internal steel profile and the height of the steel profile. , width of steel wing plate Thickness of steel wing plate Thickness of web plate of steel section Length of steel-concrete composite section Width of steel-concrete composite section Thickness of protective layer for steel profiles The built-in steel profile includes any one of H-beams, double H-beams, or partially closed steel profiles; Step 13: Collect environmental parameters, including average ambient humidity. RH ; Step 2: Based on the basic parameters of the component determined in Step 1, divide the steel section into affected zones, calculate the area of ​​the affected zones, and calculate the shortest distance from the steel section's affected zone to the edge of the steel-concrete cross-section, considering and not considering the steel's obstruction of moisture transfer to the concrete. This includes the following steps: Step 21: Based on the form of the steel-concrete composite structure with embedded steel, the cross section is divided into H-shaped steel-concrete composite, double H-shaped steel-concrete composite, and partially closed steel-concrete composite, and the steel-influenced zone is divided for each type. Step 22: Calculate the area of ​​the affected zone of the steel section; Step 23: Calculate the shortest distance from the centroid of the steel section's influence zone to the edge of the steel-concrete section, considering the steel section's obstruction of moisture transfer to the concrete. Step 24: Calculate the shortest distance from the centroid of the steel section's influence zone to the edge of the steel-concrete section, without considering the steel section's obstruction of moisture transfer to the concrete.

[0046] Step 3: Using the basic component parameters determined in Step 1, the shortest distance from the centroid of the steel-affected zone to the edge of the steel-concrete section considering the steel's obstruction of concrete moisture transfer (calculated in Step 2), and the shortest distance from the centroid of the steel-affected zone to the edge of the steel-concrete section without considering the steel's obstruction of concrete moisture transfer (calculated in Step 2), calculate the shrinkage deformation of the concrete in the non-steel-affected zone, the shrinkage deformation of the concrete in the steel-affected zone considering the steel's obstruction of concrete moisture transfer, and the shrinkage deformation of the concrete in the steel-affected zone without considering the steel's obstruction of concrete moisture transfer, according to the BS EN 1992 European standard. This includes the following steps: Step 31: Calculate the concrete shrinkage deformation in the non-steel-affected zone according to the shrinkage model of BS EN 1992 European standard; Step 32: Using the shortest distance from the centroid of the steel section's influence zone to the edge of the steel-concrete section, calculated in Step 2 and considering the steel section's obstruction of moisture transfer to concrete, replace the nominal dimension in the European standard shrinkage model. h 0, to obtain the shrinkage deformation of concrete in the steel-affected zone considering the obstruction of moisture transfer by the steel section; Step 33: Using the shortest distance from the centroid of the steel section's influence zone to the edge of the steel-concrete section, calculated in Step 2 without considering the steel section's obstruction of moisture transfer to the concrete, replace the nominal dimension in the European standard shrinkage model. h 0, obtain the shrinkage deformation of concrete in the steel-affected zone without considering the obstruction of moisture transfer by the steel section.

[0047] Step 4: Based on the area of ​​the steel-influenced zone determined in Step 2, the concrete shrinkage deformation in the non-steel-influenced zone determined in Step 3, the shrinkage deformation of the concrete in the steel-influenced zone considering the hindering effect of the steel on the transfer of moisture to the concrete, and the shrinkage deformation of the concrete in the steel-influenced zone without considering the hindering effect of the steel on the transfer of moisture to the concrete, the shrinkage deformation of the entire steel-concrete cross section is obtained by weighting the following steps: Step 41: Based on the ratio of concrete shrinkage deformation in the steel-affected zone under the condition of considering and not considering the obstruction of concrete moisture transfer by the steel section, calculated in Step 3, the steel section inhibition coefficient is obtained. Step 42: Weight the shrinkage deformation of the concrete by the ratio of the area of ​​the steel-influenced zone to that of the non-steel-influenced zone to obtain the overall steel-concrete shrinkage deformation.

[0048] like Figure 2 As shown in the figure, the H-beam's influence zone and moisture transfer distance are as follows: 1 is the flange of the H-beam; 2 is the shortest distance from the centroid of the H-beam's influence zone to the edge of the H-beam's concrete section when the obstruction of moisture transfer by the H-beam is not considered; 3 is the shortest distance from the centroid of the H-beam's influence zone to the edge of the H-beam's concrete section when the obstruction of moisture transfer by the H-beam is considered; 4 is the centroid of the H-beam's influence zone; 5 is the non-H-beam influence zone; 6 is the web of the H-beam; 7 is the H-beam influence zone.

[0049] The affected area of ​​the H-beam is from the top bottom edge. Bottom edge ,high The right-angled trapezoidal cross-section, bounded by the hypotenuse, has four steel-influenced zones. The upper base is the distance from the inner edge corner of the steel flange along the thickness direction of the steel flange to the intersection of the diagonal of the steel-concrete cross-section. The lower base is the distance from the midpoint of the long side surface of the steel web along the web surface to the inner edge of the steel flange. The height is the distance from the intersection of the steel web and flange along the surface of the steel flange to the inner edge of the steel flange. The hypotenuse is the distance from the midpoint of the long side surface of the steel web along the diagonal of the steel-concrete cross-section to the upper base of the steel-influenced zone.

[0050] like Figure 3 As shown, the influence zone and moisture transfer distance of the double H-beam are as follows: 8 is the flange of the double H-beam; 9 is the shortest distance from the centroid of the influence zone of the double H-beam to the edge of the concrete section of the steel section, without considering the obstruction of moisture transfer by the steel section to the concrete; 10 is the shortest distance from the centroid of the influence zone of the double H-beam to the edge of the concrete section of the steel section, considering the obstruction of moisture transfer by the steel section to the concrete section; 11 is the centroid of the influence zone of the double H-beam; 12 is the influence zone of the double H-beam; 13 is the influence zone of the non-double H-beam; 14 is the web of the double H-beam.

[0051] The affected area of ​​the double H-beam is from the top bottom edge. Bottom edge ,high The right-angled trapezoidal cross-section, bounded by the hypotenuse, contains eight steel-influenced zones. The upper base is the distance from the inner edge corner of the steel flange along the thickness direction of the steel flange to the intersection of the diagonal of the steel-concrete cross-section. The lower base is the distance from the intersection of the two webs of the steel section along the surface of the webs to the inner edge of the steel flange. The height is the distance from the intersection of the webs and flanges along the surface of the steel flange to the inner edge of the steel flange. The hypotenuse is the distance from the intersection of the two webs of the steel section along the diagonal of the steel-concrete cross-section to the upper base of the steel-influenced zone.

[0052] like Figure 4 As shown in the attached figure, the influence zone and moisture transfer distance of a partially enclosed steel section are as follows: 15 is the shortest distance from the centroid of the semi-enclosed influence zone to the edge of the steel-concrete section when the obstruction of moisture transfer by the steel section to the concrete is not considered; 16 is the flange of the partially enclosed steel section; 17 is the shortest distance from the centroid of the semi-enclosed influence zone to the edge of the steel-concrete section when the obstruction of moisture transfer by the steel section to the concrete is considered; 18 is the centroid of the semi-enclosed influence zone; 19 is the web of the partially enclosed steel section; 20 is the fully enclosed influence zone; 21 is the influence zone of a non-partially enclosed steel section; and 22 is the semi-enclosed influence zone.

[0053] The steel-affected zone of partially closed steel-concrete composite sections can be divided into two categories: fully enclosed and semi-enclosed. The fully enclosed affected zone is the completely enclosed area bounded by the web and flanges, consisting of one zone where the concrete cannot exchange moisture with the outside environment. The semi-enclosed affected zone is the upper bottom edge... Bottom edge ,high The right-angled trapezoidal cross-section, enclosed by the hypotenuse, contains four semi-enclosed influence zones. Within these zones, moisture exchange between the concrete and the outside environment is possible, but the moisture transfer distance is prolonged due to the obstruction of the steel profile. The upper base of the semi-enclosed influence zone is the distance from the inner edge corner of the steel flange along the thickness direction of the steel flange to the intersection of the diagonal of the steel-concrete cross-section. The lower base is the distance from the outer edge of the web where the steel web intersects with the flange to the intersection of the web and the diagonal of the steel-concrete cross-section. The height is the distance from the outer edge of the web where the steel web intersects with the flange along the inner side of the flange to the inner corner of the flange. The hypotenuse is the distance from the outer edge of the web where the steel web intersects with the diagonal of the steel-concrete cross-section to the upper base.

[0054] Preferably, the method described in this embodiment is applied in actual engineering calculations: The calculation target is a concrete specimen with built-in H-beams and a cross-sectional dimension of 100×50×5×5 mm. The cross-sectional dimensions are 150×150 mm. The concrete specimen was 400 mm high, and the H-beam protective layer was 25 mm thick. The standard value of the 28-day cylindrical compressive strength of the concrete was... The type of cement is ordinary cement. The relative humidity of the environment is Calculate the shrinkage deformation of the steel-concrete cross section after 28 days.

[0055] Calculate the parameters of the affected zone of the steel section: The length of the bottom edge of the H-beam's affected zone , The length of the H-beam's affected zone , The length of the top edge of the H-beam's affected area , Area affected by H-beams , The distance from the centroid of the affected zone of an H-beam to its right-angled side , The distance from the centroid of the affected zone of the H-beam to its top edge , Considering the hindering effect of steel on the moisture transfer of concrete, the shortest distance from the centroid of the H-beam's influence zone to the edge of the steel-concrete section is: , Without considering the obstruction of moisture transfer to concrete by the steel section, the shortest distance from the centroid of the H-section's influence zone to the edge of the steel-concrete cross-section is: , The shrinkage deformation of concrete is calculated below: Calculate the shrinkage deformation of concrete in the non-steel-affected zone: , , , , , , , , , , The time function for the development of general concrete drying shrinkage, as set according to the European standard BS EN 1992; When calculating the shrinkage deformation of the concrete in the H-beam's influence zone, considering the obstruction of moisture transfer by the steel section, the following is true: , , , , , The calculation of shrinkage deformation of concrete in the H-beam influence zone is performed without considering the obstruction of moisture transfer by the steel section. , , , , , The shrinkage deformation of the entire H-section steel-concrete cross-section is calculated below: H-beam concrete section steel damping coefficient: , H-beam concrete cross-sectional area: , Shrinkage deformation of the entire steel-concrete cross section: , The above detailed description of the technical solution provided by the present invention is intended to highlight the advantages and benefits of the technical solution provided by the present invention. However, the above detailed embodiments are not intended to limit the scope of protection of the present invention. Any reasonable modifications and improvements to the present invention, recombination of embodiments, and equivalent substitutions based on the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0056] Those skilled in the art will understand that the above description is merely a preferred embodiment of the present invention, and the features described in the various embodiments and / or claims disclosed in the present invention can be combined or combined in various ways, even if such combinations or combinations are not explicitly described in the disclosure of the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle scope of the present invention should be considered to fall within the protection scope of the present invention.

[0057] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention. Clearly, those skilled in the art can make various alterations and modifications to the invention without departing from its spirit and scope. Thus, if these modifications and modifications of the invention fall within the scope of the claims and their equivalents, the invention is also intended to include these modifications and modifications.

Claims

1. A method for calculating the shrinkage deformation of steel-concrete composite structures based on the hindering effect of steel sections on the moisture transfer of concrete, characterized in that, The method includes: S1. Collect parameters of steel-concrete composite structures; S2. Based on the parameters, the concrete section is divided into a steel-influenced zone and a non-steel-influenced zone. The steel-influenced zone is any one of an H-beam influence zone, a double H-beam influence zone, and a partially closed steel-influenced zone. The partially closed steel-influenced zone consists of a fully closed influence zone and a semi-closed influence zone. S3, Calculate the area of ​​the affected zone of the steel section; S4. Based on the area of ​​the steel section's influence zone, calculate the shortest distance from the centroid of the steel section's influence zone to the edge of the steel-concrete cross section, considering the steel section's obstruction of moisture transfer to the concrete. S5. Based on the area of ​​the steel section's influence zone, calculate the shortest distance from the centroid of the steel section's influence zone to the edge of the steel-concrete cross section, without considering the steel section's obstruction of moisture transfer to the concrete. S6. Using the concrete shrinkage calculation model, obtain the concrete shrinkage deformation in the non-steel-affected zone; S7. Replace the nominal dimension in the concrete shrinkage calculation model with the shortest distance described in S4 to obtain the concrete shrinkage deformation in the steel-affected zone when considering the obstruction of concrete moisture transmission by the steel section. S8. Replace the nominal dimension in the concrete shrinkage calculation model with the shortest distance mentioned in S5 to obtain the concrete shrinkage deformation in the steel-affected zone when the obstruction of the steel section on the moisture transfer of the concrete is not considered. S9. Based on the concrete shrinkage deformation described in S7 and S8, obtain the inhibition coefficient of the steel-affected zone. S10. Based on the inhibition coefficient of the steel section influence zone, the concrete shrinkage deformation of the steel section influence zone and the non-steel section influence zone is weighted according to the area ratio to obtain the overall steel section concrete shrinkage deformation.

2. The method according to claim 1, characterized in that, The method for calculating the area of ​​the steel section's influence zone in S3 is as follows: Area of ​​the H-beam's affected zone : ， Area of ​​the affected zone of double H-beams : ， Area of ​​the fully enclosed impact zone : ， Area of ​​the semi-enclosed influence zone : ， in, The height of the H-beam. The thickness of the flange of the H-beam. The width of the flange of the H-beam. This refers to the web thickness of the H-beam. The height of the double H-beam. The thickness of the flange of the double H-beam. The width of the flange of the double H-beam. This refers to the web thickness of a double H-beam. The height of the partially enclosed steel section. This refers to the width of the flange of a partially closed steel section. This refers to the web thickness of partially closed steel sections. This refers to the web spacing of partially closed steel sections.

3. The method according to claim 2, characterized in that, In S4, the method for calculating the shortest distance from the centroid of the steel section's influence zone to the edge of the steel-concrete cross-section, considering the steel's obstruction of moisture transfer in concrete, is as follows: The shortest distance from the centroid of the H-beam's influence zone to the edge of the steel-concrete cross-section. : ， The shortest distance from the centroid of the influence zone of the double H-beam to the edge of the steel-concrete section : ， The shortest distance from the center of gravity of the fully enclosed affected area to the edge of the steel-concrete cross-section : ， The shortest distance from the centroid of the semi-enclosed influence zone to the edge of the steel-concrete cross-section : ， in, Let be the distance from the centroid of the H-beam's affected zone to its right-angled side. This is the distance from the centroid of the H-beam's affected area to its top edge. The thickness of the protective layer for H-beams. The distance from the centroid of the affected area of ​​the double H-beam to its right-angled side is given. The distance from the centroid of the affected area of ​​the double H-beam to its upper bottom edge. The thickness of the protective layer for double H-beams. It is the distance from the centroid of the semi-enclosed influence zone to its right-angled side. It is the distance from the center of gravity of the semi-enclosed influence zone to its upper bottom edge. For the thickness of partially closed steel wing plates, This refers to the thickness of the protective layer for partially enclosed steel sections.

4. The method according to claim 3, characterized in that, In S5, the method for calculating the shortest distance from the centroid of the steel-influenced zone to the edge of the steel-concrete section, without considering the obstruction of moisture transfer to concrete by the steel section, is as follows: The shortest distance from the centroid of the H-beam's influence zone to the edge of the steel-concrete cross-section. : ， The shortest distance from the centroid of the influence zone of the double H-beam to the edge of the steel-concrete section : ， The shortest distance from the centroid of the semi-enclosed influence zone to the edge of the steel-concrete cross-section : 。 5. The method according to claim 1, characterized in that, The method for determining the concrete shrinkage deformation in the steel-affected zone when considering the hindering effect of steel on concrete moisture transfer in S7 is as follows: Concrete shrinkage deformation in the H-beam influence zone : ， Concrete shrinkage deformation in the influence zone of double H-beams : ， Concrete shrinkage deformation in the fully enclosed influence zone : ， Concrete shrinkage deformation in the semi-enclosed influence zone : ， in, For self-generated shrinkage deformation, To account for the hindering effect of steel sections on the moisture transfer of concrete, the drying shrinkage deformation of the concrete in the H-section's influence zone is considered. To account for the hindering effect of steel sections on the moisture transfer of concrete, the drying shrinkage deformation of the concrete in the affected zone of the double H-section steel section is considered. To account for the obstruction of moisture transfer to concrete by the steel profiles, the drying shrinkage deformation of the concrete in the fully enclosed affected zone is considered. When considering the obstruction of moisture transfer to concrete by the steel profile, the drying shrinkage deformation of the concrete in the semi-enclosed influence zone is taken into account.

6. The method according to claim 5, characterized in that, The method for obtaining the concrete shrinkage deformation in the steel-affected zone in S8, without considering the hindering effect of steel on concrete moisture transfer, is as follows: Concrete shrinkage deformation in the H-beam influence zone : ， Concrete shrinkage deformation in the influence zone of double H-beams : ， Concrete shrinkage deformation in the semi-enclosed influence zone : ， in, To account for the drying shrinkage deformation of concrete in the H-beam's influence zone without considering the obstruction of moisture transfer to concrete by the steel section, To account for the drying shrinkage deformation of concrete in the affected zone of the double H-beam without considering the obstruction of moisture transfer to the concrete by the steel section, This refers to the drying shrinkage deformation of concrete in the semi-enclosed influence zone without considering the obstruction of moisture transfer by the steel profile.

7. The method according to claim 6, characterized in that, The method for obtaining the inhibition coefficient of the steel section influence zone in S9 is as follows: The damping coefficient of the H-beam's influence zone ; Suppression coefficient of the affected zone of double H-beams ; The damping coefficient of the steel profile in the fully enclosed influence zone ; Suppression coefficient of steel profiles in the semi-enclosed influence zone .

8. The method according to claim 1, characterized in that, The method for obtaining the integral steel-concrete composite shrinkage deformation in S10 is as follows: ， ， in, The area of ​​the concrete cross-section. The length of the steel-concrete composite section, The width of the steel-concrete composite section. This is due to the shrinkage deformation of the integral steel-concrete composite structure. This refers to the shrinkage deformation of concrete in the non-steel-affected zone.

9. A computer storage medium for storing computer programs, characterized in that, When the computer program is read by the computer, the computer executes the method according to any one of claims 1-8.

10. A computer program product, as a computer program, is characterized by: When the computer program is read, the method of any one of claims 1-8 is implemented.

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