CN-122021132-A - Method and system for determining bearing capacity of concrete filled steel tube shaft under negative temperature

CN122021132ACN 122021132 ACN122021132 ACN 122021132ACN-122021132-A

Abstract

The application relates to the technical field of structural engineering and computational mechanics, in particular to a method and a system for determining the bearing capacity of a concrete filled steel tube shaft under negative temperature, which are used for responding to a bearing capacity calculation request, acquiring working condition parameters of a target component, constructing a finite element simulation model for simulation analysis to obtain simulation bearing capacity data, comparing the simulation bearing capacity data with a standard theoretical value calculated by a preset standard formula to obtain a deviation coefficient, and when the deviation coefficient is larger than a preset deviation threshold, adopting a preset size effect-negative temperature coupling correction model for coefficient fitting to obtain a size effect correction coefficient and a negative temperature damage correction coefficient, and correcting the standard theoretical value based on the size effect correction coefficient and the negative temperature damage correction coefficient to obtain the final bearing capacity of the shaft. The problem of among the prior art because the negative temperature adaptability that size effect and major diameter deviation lead to is poor is solved, structural risk because of the bearing capacity misjudgement causes has been avoided.

Inventors

GAO SHAN
MA BAOZHEN
ZHAO BO
ZHAO FENGHUA
LANG YANJU
Cai Jinsuo
SHI RUOCHEN
HE LISHA
LIU YING
SONG WEIFENG

Assignees

中能建西北城市建设有限公司
陕西铁肩电力建设工程技术服务有限公司

Dates

Publication Date: 20260512
Application Date: 20260106

Claims (10)

1. The method for determining the bearing capacity of the concrete filled steel tube shaft under the negative temperature is characterized by comprising the following steps of: Responding to the bearing capacity calculation request, acquiring working condition parameters of a target component, constructing a finite element simulation model, and performing simulation analysis to obtain simulated bearing capacity data; Comparing the simulated bearing capacity data with a standard theoretical value calculated by a preset standard formula to obtain a deviation coefficient; when the deviation coefficient is larger than a preset deviation threshold, performing coefficient fitting by adopting a preset size effect-negative temperature coupling correction model to obtain a size effect correction coefficient and a negative temperature damage correction coefficient; and correcting the standard theoretical value based on the size effect correction coefficient and the negative temperature damage correction coefficient to obtain the final axle pressure bearing capacity.
2. The method for determining the bearing capacity of the concrete filled steel tube shaft under the negative temperature according to claim 1, wherein the working condition parameters comprise geometric parameters, material parameters and target negative temperature environment temperature; The constructing the finite element simulation model comprises the following steps: establishing a finite element model of the steel pipe based on the geometric parameters; Based on the material parameters, an initial concrete finite element model is established, and a damage plasticity constitutive model calibrated by the target negative temperature environment temperature is adopted to endow material properties to obtain a core concrete finite element model; establishing a bonding-sliding contact relationship based on the steel pipe finite element model and the core concrete finite element model to perform interface coupling to obtain a finite element model; determining a corresponding temperature field boundary condition based on the negative temperature environment parameter; And applying the temperature field boundary condition and the axial displacement load applied according to the preset boundary condition to the finite element model to obtain a finite element simulation model.
3. The method for determining the axial pressure bearing capacity of concrete filled steel tube under negative temperature according to claim 2, wherein the step of applying the axial displacement load to the finite element simulation model under the boundary condition of the temperature field and the preset boundary condition to obtain the finite element simulation model comprises the following steps: Applying the temperature field boundary condition to the outer surface of the finite element model to obtain a temperature field finite element model; and applying the axial displacement load to the axial end part of the temperature field finite element model to obtain a finite element simulation model.
4. The method for determining the axial pressure bearing capacity of concrete filled steel tube under negative temperature according to claim 2, wherein the constructing a finite element simulation model for simulation analysis to obtain simulated bearing capacity data comprises the following steps: Performing axle pressure simulation calculation based on the finite element simulation model and the target negative temperature environment temperature to obtain simulation result data; And extracting a load-displacement curve of the finite element simulation model based on the simulation result data, and taking a peak load value of the load-displacement curve as simulation bearing capacity data.
5. The method for determining the axial compressive load of concrete filled steel tube under negative temperature according to claim 2, wherein the comparing the simulated load data with a normalized theoretical value calculated by a preset normalized formula to obtain a deviation coefficient comprises: calculating a bearing capacity value as a standard theoretical value according to a preset standard formula based on the geometric parameter and the material parameter; and comparing the simulated bearing capacity data with the standard theoretical value to obtain a deviation coefficient.
6. The method for determining the axial pressure bearing capacity of concrete filled steel tube under negative temperature according to claim 2, wherein the size effect-negative temperature coupling correction model comprises a size effect correction sub-model and a negative temperature damage correction sub-model; and if the deviation coefficient is larger than a preset deviation threshold, performing coefficient fitting by adopting a preset size effect-negative temperature coupling correction model to obtain a size effect correction coefficient and a negative temperature damage correction coefficient, wherein the method comprises the following steps of: based on the geometric parameters, performing size correction through the size effect correction model to obtain a size effect correction coefficient; and carrying out temperature correction through a negative temperature damage correction model based on the target negative temperature environment temperature to obtain a negative temperature damage correction coefficient.
7. The method for determining the bearing capacity of the concrete filled steel tube shaft under the negative temperature according to claim 1, wherein the correction of the standard theoretical value based on the size effect correction coefficient and the negative temperature damage correction coefficient is performed to obtain the final bearing capacity of the shaft, specifically: ; Wherein, the The coefficient is modified for the size effect, Is the negative temperature injury correction coefficient, Is a normalized theoretical value.
8. The utility model provides a steel pipe concrete axle pressure bearing capacity determination system under negative temperature which characterized in that includes: the data acquisition module is used for responding to the bearing capacity calculation request and acquiring working condition parameters of the target component; The simulation analysis module is used for constructing a finite element simulation model based on the working condition parameters to carry out simulation analysis so as to obtain simulation bearing capacity data; the deviation calculation module is used for comparing the simulated bearing capacity data with a standard theoretical value calculated by a preset standard formula to obtain a deviation coefficient; The correction coefficient fitting module is used for performing coefficient fitting by adopting a preset size effect-negative temperature coupling correction model when the deviation coefficient is larger than a preset deviation threshold value to obtain a size effect correction coefficient and a negative temperature damage correction coefficient; And the bearing capacity correction module is used for correcting the standard theoretical value based on the size effect correction coefficient and the negative temperature damage correction coefficient to obtain the final axle pressure bearing capacity.
9. An electronic device comprising a memory and a processor, wherein the memory stores a computer program, which when executed by the processor, causes the processor to perform the steps of the method for determining the axial bearing capacity of concrete filled steel tube at negative temperature as claimed in any one of claims 1 to 7.
10. A computer readable storage medium having stored thereon a computer program, wherein the computer program when executed implements the method for determining the bearing capacity of a concrete filled steel tube shaft at negative temperature as claimed in any one of claims 1 to 7.

Description

Method and system for determining bearing capacity of concrete filled steel tube shaft under negative temperature Technical Field The application relates to the technical field of structural engineering and computational mechanics, in particular to a method and a system for determining the bearing capacity of a concrete filled steel tube shaft under negative temperature. Background With the development of modern buildings to large-scale, super high-rise and extreme climate areas, concrete filled steel tubes are widely used due to their excellent bearing and deformation capabilities. However, in severe cold areas or low temperature environments, the mechanical properties of concrete filled steel tubular columns will be significantly degraded, and accurate assessment of the axial pressure bearing capacity becomes a core problem that directly affects structural safety and design economy. Industry practice shows that the traditional standard formula based on normal temperature test has systematic deviation when predicting the component behavior under negative temperature, and especially for large-size components, the insufficient prediction of the bearing capacity loss caused by the size effect and the low-temperature brittleness of the material can become potential safety hazard of the structure under extreme working conditions. Therefore, a bearing capacity determining method capable of accurately reflecting the size effect and the negative temperature coupling effect is developed, the method has great significance in guaranteeing the safe service of a great engineering structure in a cold region, and the demand is pushing the related design theory to change from an empirical formula to a prediction model based on refined simulation and multi-factor correction. At present, research on concrete filled steel tubes at negative temperature is focused on experimental analysis of a material constitutive or small-scale test piece, and the bearing capacity prediction mainly depends on introducing a single negative Wen Shejian coefficient to a normal temperature standard formula. Some of the improved methods have been parameterized by building finite element models to widen the application range, but have inherent limitations in handling large diameter, large size components that are prevalent in practical engineering. Existing methods typically ignore nonlinear interactions between dimensional effects and negative temperature damage due to component diameter or dimensional changes, and simple superposition of the two effects may lead to safe or economical misalignment of the predicted results. Meanwhile, most standard formulas or empirical models rely on limited test data calibration, and parameters of the standard formulas or empirical models are insufficient in adaptability when component sizes, concrete strength and negative temperature ranges are greatly changed, so that obvious and unstable deviation is generated between theoretical calculation values and real responses of bearing capacity, and reliability and comparability of design results are seriously affected. The existing method for determining the bearing capacity of the concrete filled steel tube shaft under the negative temperature faces three main problems that a theoretical model lacks quantitative description of a coupling mechanism of a size effect and a negative temperature environment, so that prediction accuracy of a large-diameter or nonstandard-size component is reduced, the design method depending on a fixed formula and a reduction coefficient is not flexible enough, complex and changeable material combination and working condition conditions are difficult to cover, the bearing capacity determining process and high-fidelity simulation analysis are relatively cracked, and a complex mechanism revealed by numerical simulation cannot be fully utilized to dynamically and target correct an empirical formula, so that robustness of the method is poor when the method is used for coping with new working conditions or boundary conditions. Disclosure of Invention In view of the above, the application provides a method and a system for determining the bearing capacity of a concrete filled steel tube shaft under negative temperature, which are used for solving the problem of poor adaptability to the negative temperature caused by the deviation of the size effect and the large diameter in the prior art by constructing a size effect-negative temperature coupling correction model and fitting and correcting a standard theoretical value based on finite element simulation data, enhancing the scientificity and engineering applicability of the bearing capacity determination of the shaft and avoiding the structural risk caused by the misjudgment of the bearing capacity, and have outstanding application value in the fields of design and safety evaluation of extreme environment civil engineering. The application provides a method and a system for determining the beari