Method for calculating longitudinal temperature deformation of top of multi-span I-shaped steel composite beam integral bridge abutment

Abstract

The invention belongs to the technical field of bridge design, and particularly relates to a method for calculating longitudinal temperature deformation of the top of a multi-span I-shaped steel composite beam integral bridge abutment, which comprises the following steps of: based on theoretical analysis, comparing stress characteristics of integral bridges with different span numbers, establishing a longitudinal beam theoretical calculation method under the action of temperature of a multi-span integral bridge, and verifying the correctness of the longitudinal beam theoretical calculation method; and obtaining the longitudinal deformation calculation method for the top of the abutment under the action of the temperature of the multi-span I-shaped steel composite beam integral bridge.

Description

Technical Field

[0001] The invention belongs to the technical field of bridge design, and in particular relates to a method for calculating the longitudinal temperature deformation of a bridge abutment top of a multi-span I-beam composite beam integral bridge. Background Art

[0002] Standardizing design work is to improve the efficiency of bridge design and construction. Designing a series of drawings of different components of bridge structures according to certain modules and specifications can facilitate reference and selection by design and construction units.

[0003] On the other hand, in the standardized design process of multi-span I-beam composite beam integral bridges, the issue of reasonable bridge length needs to be given priority consideration.

[0004] As the length of the bridge continues to increase, the longitudinal deformation of the bridge under the action of temperature will also continue to increase. Therefore, it is necessary to clarify the reasonable bridge length of the multi-span I-beam composite beam integral bridge based on the calculation of the longitudinal deformation of the abutment top under the action of temperature. Summary of the invention

[0005] The invention provides a method for calculating the longitudinal temperature deformation of the abutment top of a multi-span I-beam composite beam integral bridge, aiming at clarifying the reasonable bridge length of the multi-span I-beam composite beam integral bridge.

[0006] The technical solution adopted by the present invention to solve the above problem is: a method for calculating the longitudinal temperature deformation of the top of the abutment of a multi-span I-beam composite beam integral bridge. For an odd-numbered span integral bridge, the deformation zero point is located at the middle of the middle span; for an even-numbered span integral bridge, the deformation zero point is located at 1 / 2 of the bridge length. The deformation of the multi-span integral bridge at the abutment ΔL n , determined according to formula (1),

[0007]

[0008] Among them, E s is the elastic modulus of steel, A0 is the converted main beam cross-sectional area, α is the linear expansion coefficient of steel, ΔT is the temperature change, n p is the number of piles, V p is the maximum shear capacity of the pile top, K0 is the static earth pressure coefficient, γ is the unit weight of the backfill soil, H b is the abutment height, w b is the abutment width, c n is the pier-beam connection stiffness K n-1 , span L, main beam elastic modulus E, main beam converted cross-sectional area A0 determined deformation coefficient, k p is the passive earth pressure coefficient.

[0009] A further preferred technical solution is that the longitudinal deformation ΔL at the i-th pier beam adjacent to the zero point of deformation is i There is a linear relationship between the longitudinal deformation ΔL1 of the first pier beam adjacent to the zero point of deformation and it is determined according to formula (2):

[0010] ΔL i =c i ΔL1 (2),

[0011] Among them, c i The pier-beam connection stiffness K i-1 , span L, main beam elastic modulus E, main beam converted cross-sectional area A0 to determine the deformation coefficient,

[0012] The longitudinal deformation ΔL1 at the first pier beam adjacent to the deformation zero point is determined according to formula (3):

[0013]

[0014] A further preferred technical solution is: the span number n s When is an odd number or an even number, the deformation coefficient ci is determined according to formulas (4-1) and (4-2), respectively.

[0015] Span number n s =2n-1 is an odd number;

[0016] Span number n s =2n is an even number,

[0017] Among them, K i-1 is the stiffness of the pier top of the adjacent piers in the i-th span, and its value can be determined according to the pier-beam connection strength.

[0018] A further preferred technical solution is: the pier top stiffness K under different pier-beam connection conditions p , determined according to formula (5),

[0019]

[0020] Among them, E p I p is the bending stiffness of the bridge pier, H p is the height of the bridge pier. DETAILED DESCRIPTION

[0021] The following descriptions are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention.

[0022] The calculation method of the longitudinal temperature deformation of the abutment top of a multi-span I-beam composite bridge is as follows: for an odd-numbered span integral bridge, the deformation zero point is located at the middle of the middle span; for an even-numbered span integral bridge, the deformation zero point is located at 1 / 2 of the bridge length.

[0023] Deformation ΔL of a multi-span integral bridge at the abutment n , determined according to formula (1),

[0024]

[0025] Among them, E s is the elastic modulus of steel, A0 is the converted main beam cross-sectional area, α is the linear expansion coefficient of steel, ΔT is the temperature change, n p is the number of piles, V p is the maximum shear capacity of the pile top, K0 is the static earth pressure coefficient, γ is the unit weight of the backfill soil, H b is the abutment height, w b is the abutment width, c n is the pier-beam connection stiffness K n-1 , span L, main beam elastic modulus E, main beam converted cross-sectional area A0 determined deformation coefficient, k p is the passive earth pressure coefficient.

[0026] The longitudinal deformation ΔL at the i-th pier beam adjacent to the zero point of deformation i There is a linear relationship between the longitudinal deformation ΔL1 of the first pier beam adjacent to the zero point of deformation and it is determined according to formula (2):

[0027] ΔL i =c i ΔL1 (2),

[0028] Among them, c i The pier-beam connection stiffness K i-1 , span L, main beam elastic modulus E, main beam converted cross-sectional area A0 to determine the deformation coefficient,

[0029] The longitudinal deformation ΔL1 at the first pier beam adjacent to the deformation zero point is determined according to formula (3):

[0030]

[0031] Span number n s When is an odd number or an even number, the deformation coefficient ci is determined according to formulas (4-1) and (4-2), respectively.

[0032] Span number n s =2n-1 is an odd number;

[0033] Span number ns =2n is an even number,

[0034] Among them, K i-1 is the stiffness of the pier top of the adjacent piers in the i-th span, and its value can be determined according to the pier-beam connection strength.

[0035] Pier top stiffness K under different pier-beam connection conditions p , determined according to formula (5),

[0036]

[0037] Among them, E p I p is the bending stiffness of the bridge pier, H p is the height of the bridge pier.

[0038] The specific implementation of the calculation method includes the following steps in sequence:

[0039] Step 1: According to the design results of the number of spans, there are two different cases: odd spans and even spans. Calculate them separately. When the number of spans is odd, it is determined according to formula (4-1); when the number of spans is even, it is determined according to formula (4-2), and the deformation coefficient c is calculated using formula (2). n ;

[0040] Step 2: Based on the pier bending stiffness and pier height, calculate the pier top stiffness K using formula (5): p ;

[0041] Step 3: Based on the elastic modulus of steel, converted main beam cross-sectional area, steel linear expansion coefficient, temperature change, number of piles, maximum shear capacity of pile top, static earth pressure coefficient, unit weight of backfill soil, abutment height, abutment width, deformation coefficient and passive earth pressure coefficient, use formula (3) to calculate the longitudinal deformation ΔL1 of the first pier beam adjacent to the deformation zero point of the multi-span I-beam composite beam integral bridge, and then use formula (1) to calculate the deformation ΔL of the multi-span I-beam composite beam integral bridge at the abutment n .

[0042] The above describes the embodiments of the present invention in detail, but the present invention is not limited to the above embodiments. Various modifications can be made within the knowledge of ordinary technicians in the technical field without departing from the purpose of the present invention. These are all non-creative modifications and are protected by patent law as long as they are within the scope of the claims of the present invention.

Claims

1. A method for calculating the longitudinal temperature deformation of the abutment top of a multi-span I-beam composite bridge, characterized in that: For an odd-numbered span integral bridge, the deformation zero point is located at the middle of the middle span; for an even-numbered span integral bridge, the deformation zero point is located at 1 / 2 of the bridge length. Deformation ΔL of a multi-span integral bridge at the abutment n , determined according to formula (1), Among them, E s is the elastic modulus of steel, A0 is the converted main beam cross-sectional area, α is the linear expansion coefficient of steel, ΔT is the temperature change, n p is the number of piles, V p is the maximum shear capacity of the pile top, K0 is the static earth pressure coefficient, γ is the unit weight of the backfill soil, H b is the abutment height, w b is the abutment width, c n is the pier-beam connection stiffness K n-1 , span L, main beam elastic modulus E, main beam converted cross-sectional area A0 determined deformation coefficient, k p is the passive earth pressure coefficient.

2. The method for calculating the longitudinal temperature deformation of the abutment top of a multi-span I-beam composite beam integral bridge according to claim 1 is characterized by: The longitudinal deformation ΔL at the i-th pier beam adjacent to the zero point of deformation i There is a linear relationship between the longitudinal deformation ΔL1 of the first pier beam adjacent to the zero point of deformation and it is determined according to formula (2): ΔL i =c i ΔL1 (2), Among them, c i The pier-beam connection stiffness K i-1 , span L, main beam elastic modulus E, main beam converted cross-sectional area A0 to determine the deformation coefficient, The longitudinal deformation ΔL1 at the first pier beam adjacent to the deformation zero point is determined according to formula (3):

3. The method for calculating the longitudinal temperature deformation of the abutment top of a multi-span I-beam composite beam integral bridge according to claim 2 is characterized by: Span number n s When is an odd number or an even number, the deformation coefficient ci is determined according to formulas (4-1) and (4-2), respectively. Span number n s =2n-1 is an odd number; Span number n s =2n is an even number, Among them, K i-1 is the stiffness of the pier top of the adjacent piers in the i-th span, and its value can be determined according to the pier-beam connection strength.

4. The method for calculating the longitudinal temperature deformation of the abutment top of a multi-span I-beam composite beam integral bridge according to claim 3 is characterized by: Pier top stiffness K under different pier-beam connection conditions p , determined according to formula (5), Among them, E p I p is the bending stiffness of the bridge pier, H p is the height of the bridge pier.

Images