Method for determining ultimate shearing capacity and load-slip curve, computer system, computer storage medium

Abstract

The application discloses a method for determining the ultimate shear bearing capacity of a steel-UHPC combined structure bolt group shear connector, and comprises the following steps: obtaining the bolt row number n p , the bolt cross-sectional area A s , the tensile strength f u of the bolt, the compressive strength f c of the UHPC, the weld diameter d wc , the weld height l wc , the contribution coefficient η of the weld to the shear bearing capacity, the resistance coefficient γ V , the shear bearing capacity reduction coefficient μ of the bolt group shear connector, and obtaining the ultimate shear bearing capacity P G of the steel-UHPC combined structure bolt group shear connector based on the obtained parameters. The application also provides a method for determining the load-slip curve of the steel-UHPC combined structure bolt group shear connector, a computer system and a computer storage medium. The method for determining the ultimate shear bearing capacity of the bolt group shear connector and the method for determining the load-slip curve are efficient and accurate, and have great practical engineering application value.

Description

Technical Field

[0001] This invention belongs to the field of bridge structure design, and particularly relates to a method for calculating the stress performance of a stud shear connector, as well as a computer system and computer storage medium. Background Technology

[0002] Steel-UHPC composite structures are increasingly used in bridges. In these structures, studs are welded to steel plates, and the steel plates and UHPC are typically connected as a whole by long studs. The load-slip curves, shear capacity, and shear stiffness of the long studs in the UHPC are crucial for the design calculations of steel-UHPC composite structures. Therefore, predicting the load-slip curves and shear capacity of the studs in the UHPC is essential for the calculation of steel-UHPC composite structures.

[0003] Scholars both domestically and internationally have proposed numerous empirical formulas for fitting the load-slip curves and shear capacity of studs in ordinary and high-strength concrete. However, due to the significant differences in matrix composition and mechanical properties between ultra-high-strength concrete (UHPC) and conventional concrete, these formulas may not be applicable to studded connections in UHPC. Furthermore, many of the proposed formulas are based on single-stud pull-out tests, but stud-group specimens exhibit a significant decrease in stiffness compared to single-stud specimens. Therefore, it is necessary to develop empirical formulas applicable to the load-slip and shear capacity of long stud groups in UHPC, providing technical support for the design and calculation of this type of steel-UHPC composite structure. Summary of the Invention

[0004] The technical problem to be solved by this invention is to overcome the deficiencies and defects mentioned in the background art above, and to provide a method for determining the ultimate shear bearing capacity of shear connections for steel-UHPC composite structures with stud groups (long studs), a method for determining the load-slip curve, and a computer system and computer storage medium, all with high accuracy. To solve the above technical problem, the technical solution proposed by this invention is as follows:

[0005] A method for determining the ultimate shear capacity of a shear connector group in a steel-UHPC composite structure includes the following steps: obtaining the number of rows of studs n. p Cross-sectional area A of the stud s (Cross-sectional area of ​​the bolt) (mm) 2 ), tensile strength f of the stud u (MPa), compressive strength f of UHPC c (MPa), weld diameter d wc (mm), weld height l wc (mm), contribution coefficient of weld to shear bearing capacity η, resistance coefficient γ VThe reduction factor μ for the shear capacity of the shear connector group of the stud group is used to obtain the ultimate shear capacity P of the shear connector group of the steel-UHPC composite structure based on the parameters obtained above. G It satisfies the following relationship:

[0006] P G =μn p (0.85A s f u +ηf c d wc l wc ) / γ V .

[0007] In the above determination method, preferably, the contribution coefficient η of the weld to the shear bearing capacity satisfies the following relationship: η=0.0119f c -0.983, where f c This represents the compressive strength of UHPC.

[0008] In the above determination method, preferably, the resistance coefficient γ V It is 1.25.

[0009] In the above determination method, preferably, the shear capacity reduction factor μ of the stud group shear connector satisfies the following relationship: μ=0.996-0.021n p +0.03 / n p , where n p This refers to the number of rows of studs.

[0010] In this invention, when determining the ultimate shear capacity of the shear connection of the stud group in the steel-UHPC composite structure, both the stud group and the UHPC are fully considered, and the number of stud rows n is introduced. p The compressive strength f of UHPC c The parameters are considered, including the contribution coefficient η of the weld to the shear bearing capacity and the reduction coefficient μ of the shear bearing capacity of the stud group shear connector. Through the introduction and optimization of multiple parameters, the final result of the ultimate shear bearing capacity of the stud group shear connector has a wide range of applications and high accuracy.

[0011] As a general technical concept, the present invention also provides a method for determining the load-slip curve of a shear connector with studs in a steel-UHPC composite structure, comprising the following steps: obtaining the load P on the shear connector with studs, the stud diameter d (mm), and the relative slip S between the steel plate and the UHPC; and obtaining the load-slip curve of the shear connector with studs in the steel-UHPC composite structure based on the parameters obtained above, which satisfies the following relationship:

[0012]

[0013] Where e is the natural constant, P G The ultimate shear bearing capacity of the shear connection group of the steel-UHPC composite structure obtained above is given.

[0014] As a general technical concept, the present invention also provides a computer system including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of any of the methods described above.

[0015] As a general technical concept, the present invention also provides a computer storage medium having a computer program stored thereon, characterized in that the program, when executed by a processor, implements the steps in any of the methods described above.

[0016] Compared with the prior art, the advantages of the present invention are as follows:

[0017] This invention presents a method for determining the ultimate shear capacity of studded shear connectors in steel-UHPC composite structures. This method comprehensively considers factors such as the reduction in shear capacity due to the number of stud rows, the contribution of welds to the shear capacity, stud strength, and UHPC strength. Based on the differences in mechanical properties between UHPC and ordinary concrete, this invention proposes a highly applicable and accurate method for determining the shear capacity of studded shear connectors in UHPC structures. The method for determining the load-slip curve of studded shear connectors in steel-UHPC composite structures can simultaneously consider the slip value between the steel plate and the UHPC block and the stud diameter, accurately determining the load-slip relationship of the studded shear connectors in steel-UHPC composite structures.

[0018] The method for determining the ultimate shear capacity of the group-staple shear connector and the method for determining the load-slip curve of the present invention are efficient, accurate, simple and easy to implement, and have great practical engineering application value in the field of steel-UHPC composite structure bridges. Detailed Implementation

[0019] To facilitate understanding of the present invention, the present invention will be described more fully and in detail below with reference to preferred embodiments, but the scope of protection of the present invention is not limited to the following specific embodiments.

[0020] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention.

[0021] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this invention can be purchased from the market or prepared by existing methods.

[0022] Example:

[0023] A method for determining the ultimate shear capacity of a shear connector group in a steel-UHPC composite structure includes the following steps: obtaining the number of rows of studs n. p Cross-sectional area A of the stud s The tensile strength f of the stud u The compressive strength f of UHPC c weld diameter d wc weld height l wc The contribution coefficient η and resistance coefficient γ of the weld to the shear bearing capacity. V The reduction factor μ for the shear capacity of the shear connector group of the stud group is used to obtain the ultimate shear capacity P of the shear connector group of the steel-UHPC composite structure based on the parameters obtained above. G It satisfies the following relationship:

[0024] P G =μn p (0.85A s f u +ηf c d wc l wc ) / γ V .

[0025] Specifically, in this embodiment, the contribution coefficient of the weld to the shear bearing capacity η = 0.0119fc - 0.983, and the resistance coefficient γ V The reduction factor for the shear capacity of the stud group shear connector is μ = 0.996 - 0.021n, which is 1.25. p +0.03 / n p .

[0026] The ultimate shear bearing capacity P of the shear connector group of the steel-UHPC composite structure is... G It satisfies the following relationship:

[0027] P G =n p (0.996-0.021n p +0.03 / n p (0.85A) s f u +(0.0119f c -0.983)f c d wc l wc ) / γ V .

[0028] The method for determining the load-slip curve of the shear connector of the steel-UHPC composite structure in this embodiment includes the following steps: obtaining the load P on the shear connector of the shear connector of the shear connector of the shear connector of the shear connector of the shear connector of the shear connector of the shear connector of the shear connector of the shear connector of the shear connector of the shear connector of the shear connector of the shear connector of the shear connector of the shear connector of the steel-UHPC composite structure based on the above-obtained parameters, and obtaining the load-slip curve of the shear connector of the shear connector of the steel-UHPC composite structure, which satisfies the following relationship:

[0029]

[0030] Where e is the natural constant, P G The ultimate shear bearing capacity of the shear connection group of the steel-UHPC composite structure obtained above is given.

[0031] This embodiment also provides a computer system, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of any of the methods described above.

[0032] This embodiment also provides a computer storage medium storing a computer program thereon, characterized in that the program, when executed by a processor, implements the steps in any of the methods described above.

[0033] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific application embodiments. It should be understood that the specific examples described herein are merely illustrative and not intended to limit the invention.

[0034] Specific application examples:

[0035] Shear stud connectors used in steel-UHPC lightweight composite bridge decks and steel-UHPC composite beams were selected as verification samples through pull-out tests. The stud strength ranged from 360-484 MPa, the stud diameter from 16-25 mm, and the UHPC strength from 131-180 MPa. These samples were compiled into Database I, and calculations were performed using the methods described above. The comparison results are shown in Tables 1 and 2 below.

[0036] Table 1: Calculation error of shear bearing capacity of group-stapled shear connectors in Database I

[0037]

[0038] Note: AVG, STDEV, and COV represent the calculation error (experimental value P). u With the calculated value P cal The mean, standard deviation, and variance of the ratio (to each other).

[0039] Table 2: Calculation error of load-slip curve in Database I

[0040]

[0041] Note: S max The values ​​represent the experimental relative slip between the steel plate and the UHPC. AVG, STDEV, and COV are the calculation errors (experimental value P / P). u Comparison with calculated value P / P cal The mean, standard deviation, and variance of the ratio (to each other).

[0042] Tables 1 and 2 present a comparison between experimental and calculated values ​​of the ultimate shear capacity and load-slip relationship of the shear connectors in the steel-UHPC composite structure from Database I. As can be seen from the tables, the database samples in this embodiment cover a variety of situations, demonstrating high calculation accuracy and good precision for all cases. The method for determining the ultimate shear capacity and load-slip curves of the shear connectors in this embodiment exhibits good accuracy and applicability.

Claims

1. A method for determining the load-slip curve of a shear connector with studs in a steel-UHPC composite structure, characterized in that, Includes the following steps: Obtain the load on the shear connection of the stud group P stud diameter d The relative slip between the steel plate and the UHPC S Based on the parameters obtained above, the load-slip curves of the shear connectors of the steel-UHPC composite structure are obtained, which satisfy the following relationship: ； in, e It is a natural constant. P G The ultimate shear capacity of shear connectors in a steel-UHPC composite structure is determined by the following steps: obtaining the number of stud rows. n p cross-sectional area of ​​the stud A s Tensile strength of studs f u UHPC compressive strength f c weld diameter d wc weld height l wc Contribution coefficient of weld to shear bearing capacity η Resistance coefficient γ V Shear capacity reduction factor for shear connectors with studs μ Based on the parameters obtained above, the ultimate shear bearing capacity of the shear connector of the stud group in the steel-UHPC composite structure is calculated. P G It satisfies the following relationship: Shear capacity reduction factor for studded shear connectors μ The following relationship must be satisfied: μ =0.996-0.021 n p +0.03 / n p ,in, n p This refers to the number of rows of studs.

2. The determination method according to claim 1, characterized in that, Contribution coefficient of weld to shear capacity η The following relationship must be satisfied: η =0.0119 f c -0.983, of which, f c This represents the compressive strength of UHPC.

3. The determination method according to claim 1, characterized in that, resistance coefficient γ V It is 1.

25.

4. A computer system comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method described in any one of claims 1-3.

5. A computer storage medium having a computer program stored thereon, characterized in that, When the program is executed by a processor, it implements the steps of the method described in any one of claims 1-3.

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