A method for designing the interface position of a vertical rotation connection structure for a reinforced concrete bridge tower.

Abstract

This invention belongs to the field of bridge engineering technology, specifically relating to a method for designing the interface position of a vertical rotation connection structure for a steel-concrete bridge tower. The method includes the following steps: determining the lower limit condition factors affecting the lower limit height of the interface of the steel-concrete bridge tower; calculating and determining the lower limit height of the interface based on the lower limit condition factors; determining the upper limit condition factors affecting the upper limit height of the interface of the steel-concrete bridge tower; calculating and determining the upper limit height of the interface based on the upper limit condition factors; calculating the optimal interface height based on stiffness transition factors; and determining the final interface position. This invention establishes a scientific and systematic method for determining the interface position, transforming the original qualitative judgment relying on experience into quantitative calculation, thus improving the scientificity and reliability of decision-making.

Description

Technical Field

[0001] This invention belongs to the field of bridge engineering technology, specifically relating to a method for designing the interface position of a vertical rotation connection structure for a steel-concrete bridge tower. Background Technology

[0002] In the current construction of long-span bridges, steel-concrete composite bridge towers are increasingly used in trunk lines and cross-river and cross-sea projects due to their advantages of strong structural bearing capacity and good overall economy. For the vertical rotation construction process of steel-concrete composite bridge towers, the most critical and difficult technical challenge to control on site lies in determining the position of the rotation interface. Engineering practice shows that whether the selection of this interface is reasonable directly determines the feasibility of construction, structural safety and the overall cost of the project.

[0003] Existing technologies for determining the location of the rotation interface have several problems, including structural interference, insufficient consideration of the influence of temporary structures, and difficulty in controlling stress risks. To address these issues, a design method for the interface location of the vertical rotation connection structure of a steel-concrete bridge tower is proposed. Summary of the Invention

[0004] In order to solve the technical problems existing in the prior art, the present invention provides a method for designing the interface position of the vertical rotation connection structure of a steel-concrete bridge tower.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a method for designing the interface position of a vertical rotation connection structure for a steel-concrete bridge tower, comprising the following steps:

[0006] Step S1: Determine the lower limit height of the interface affecting the steel-concrete bridge tower. The lower limit condition factors are used to calculate the lower limit height of the interface. ;

[0007] Step S2: Determine the upper limit height of the interface affecting the steel-concrete bridge tower. The upper limit condition factors are used to calculate the upper limit height of the interface. ;

[0008] Step S3: Determine the optimal interface height of the steel-concrete bridge tower. Based on the stiffness condition factors, the optimal interface height is calculated. ;

[0009] Step S4, based on the optimal interface height Interface lower limit height and the maximum height of the interface Establish the final interface location The determination rules are used to determine the final interface position. .

[0010] Preferably, step S1 includes:

[0011] Step S11: The steel-concrete bridge tower includes a lower concrete tower column, a steel-concrete composite section, an upper steel tower column, and a main beam. The connection surface between the steel-concrete composite section and the upper steel tower column is the interface of the steel-concrete bridge tower. The lower limit condition factors include: the height of the steel-concrete composite interface in the steel-concrete composite section relative to the top of the main beam. The required welding space for the steel upper tower column after rotation is relative to the height of the top of the main beam. The height of the hinge installed on the concrete lower tower column relative to the top of the main beam The height of the steel strand storage space within the steel-concrete composite section relative to the top of the main beam. De-icing agent splash affects altitude ;

[0012] Establish the lower limit height of the interface based on lower limit conditions. The calculation formula:

[0013] ;

[0014] Step S12, based on the lower limit height of the interface The calculation formula yields the lower limit height of the interface. .

[0015] Preferably, in step S11, a crash barrier is installed on the main beam. The de-icing agent, when compressed, forms splashes, and these splashes affect the height of the object. The calculation formula is:

[0016] ;

[0017] In the formula, For the height of the crash barrier, The projectile height of the debris on the guardrail surface. The projectile height of the projectile on the surface of the reinforced concrete bridge tower. This is a correction factor;

[0018] The height of the projectiles on the surface of the guardrail The formula for calculation is:

[0019] ;

[0020] In the formula, The horizontal distance from the point of wheel splash to the oncoming side of the crash barrier. For vehicle speed, For the wheel splash projection angle, It is the acceleration due to gravity;

[0021] The height of the projectiles on the surface of the reinforced concrete bridge tower The formula for calculation is:

[0022] ;

[0023] In the formula, The horizontal distance from the point of wheel splash to the oncoming side of the bridge tower.

[0024] Preferably, in step S11, the height of the steel strand storage space is... The calculation formula is:

[0025] ;

[0026] In the formula, The installation height of the anchor relative to the top of the main beam. The exposed length of the tensioning end of the steel strand. This is the minimum storage radius for steel strands. This is the arrangement coefficient. The diameter of the steel strand. The number of layers in the steel strand storage reel;

[0027] ;

[0028] In the formula, This refers to the total number of strands in the coil.

[0029] Preferably, in step S11, the installation height of the hinge... The calculation formula is:

[0030] ;

[0031] In the formula, The mounting height of the hinge base. For the dimensions of the hinge, This refers to the weld seam distance of the bracket in the hinge.

[0032] Preferably, step S2 includes:

[0033] Step S21, the upper limit condition factors include the lifting operation height limit. Construction jig stability limit height and construction avoidance height restrictions The structure includes a manhole or a diaphragm.

[0034] Step S22: Establish the upper limit height of the interface based on the upper limit condition factors. The calculation formula:

[0035] ;

[0036] Step S23: Establish the upper limit height of the interface based on the upper limit condition factors. The calculation formula yields the upper limit height of the interface. .

[0037] Preferably, in step S21, the hoisting operation height is limited. The calculation formula is:

[0038] ;

[0039] In the formula, The height of the crane's slewing center. This refers to the actual maximum length of the crane boom. The working radius of the crane. The total height of rigging and lifting equipment. To ensure safe passage through the gap during hoisting and lifting.

[0040] Preferably, in step S21, the stability limit height of the construction jig is... The calculation formula is:

[0041] ;

[0042] In the formula, This is the length coefficient. For elastic modulus, The equivalent moment of inertia of the construction formwork section, The design load for the construction formwork.

[0043] Preferably, step S3 includes:

[0044] Step S31, the stiffness condition factors include the length of the transition section of the steel upper tower column. Bending stiffness of steel tower columns Bending stiffness of concrete lower tower column and stiffness transition coefficient Stiffness transition coefficient This is an empirical constant, and it takes any value between 0.8 and 1.0 in the calculation.

[0045] Step S32: Establish the optimal interface height based on stiffness condition factors. The calculation formula:

[0046] ;

[0047] Step S33: Calculate the optimal interface height. .

[0048] Preferably, in step S4, the final interface position The rules for determining it are as follows:

[0049] When the optimal interface height < Lower limit height of the interface Then, the final interface position = Lower limit height of the interface ;

[0050] When the lower limit height of the interface <Optimal Interface Height <Maximum Height of Interface> Then, the final interface position =Optimal interface height ;

[0051] When the optimal interface height > Maximum height of the interface Then, the final interface position =Maximum height of the interface ;

[0052] The calculated optimal interface height Interface lower limit height and the maximum height of the interface The value is substituted into the determination rule and judged. Based on the judgment result, the final interface position is output. .

[0053] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0054] 1. This invention establishes a scientific and systematic method for determining the interface location. By quantifying factors such as structure, construction, and stress, it transforms qualitative judgments that originally relied on experience into quantitative calculations, thereby improving the scientificity and reliability of decision-making.

[0055] 2. This invention ensures that the interface position does not conflict with the permanent structure by limiting the steel-concrete interface, the hinge installation size, and the steel strand storage space, thus effectively avoiding structural interference.

[0056] 3. This invention fully considers construction conditions and ensures the feasibility of the construction plan through upper limit constraints such as hoisting operation restrictions and construction frame stability restrictions;

[0057] 4. This invention determines the optimal position through a stiffness gradual change optimization formula, avoiding stress concentration caused by sudden changes in local stiffness and reducing construction risks;

[0058] 5. This invention is applicable to the vertical rotation construction of steel-concrete composite bridge towers with different spans and heights, and has good promotion and application value. Attached Figure Description

[0059] Figure 1 This is a schematic diagram of the process of the present invention;

[0060] Figure 2 This is a cross-sectional structural diagram of the present invention;

[0061] Figure 3 This is a schematic diagram of the steel-concrete bridge tower structure of the present invention;

[0062] Figure 4 This is a partial structural diagram of the steel-concrete bridge tower of the present invention;

[0063] Figure 5 This is a schematic diagram of the prestressed anchorage system structure of the present invention.

[0064] The numbers in the diagram represent: 1. Steel-concrete bridge tower; 11. Concrete lower tower column; 12. Steel-concrete composite section; 13. Steel upper tower column; 2. Main beam. Detailed Implementation

[0065] The present invention will be further described below with reference to the accompanying drawings and embodiments, which illustrate the above and other technical features and advantages of the present invention. However, the following embodiments are only preferred embodiments of the present invention and are not all of them.

[0066] Example 1:

[0067] like Figure 1-5 As shown, the present invention provides a method for designing the interface position of a vertical rotation connection structure for a steel-concrete bridge tower, comprising the following steps:

[0068] Step S1: Determine the lower limit height of the interface affecting the steel-concrete bridge tower 1. The lower limit condition factors are used to calculate the lower limit height of the interface. ;

[0069] Step S11, the steel-concrete bridge tower 1 includes a concrete lower tower column 11, a steel-concrete composite section 12, a steel upper tower column 13 and a main beam 2, and the connection surface between the steel-concrete composite section 12 and the steel upper tower column 13 is the interface of the steel-concrete bridge tower 1.

[0070] The lower limit conditions include: the height of the steel-concrete joint surface in steel-concrete joint section 12 relative to the top of the main beam 2. The required welding space for the steel upper tower column 13 after rotation is relative to the height of the top of the main beam 2. The height of the hinge installed on the concrete lower tower column 11 relative to the top of the main beam 2 The height of the steel strand storage space within the steel-concrete composite section 12 relative to the top of the main beam 2 De-icing agent splash affects altitude ;

[0071] In step S11, a crash barrier is installed on the main beam 2. When the de-icing agent is compressed, it forms splashes, which affect the height. The calculation formula is:

[0072] ;

[0073] In the formula, For the height of the crash barrier, The projectile height of the debris on the guardrail surface. The projectile height of the projectile on the surface of the reinforced concrete bridge tower 1. This is a correction factor;

[0074] The height of the projectiles on the surface of the guardrail The formula for calculation is:

[0075] ;

[0076] In the formula, The horizontal distance from the point of wheel splash to the oncoming side of the crash barrier. For vehicle speed, For the wheel splash projection angle, It is the acceleration due to gravity;

[0077] Projectile height on the surface of the reinforced concrete bridge tower 1 The formula for calculation is:

[0078] ;

[0079] In the formula, The horizontal distance from the point of wheel splash to the oncoming side of the bridge tower;

[0080] Establish the lower limit height of the interface based on lower limit conditions. The calculation formula:

[0081] ;

[0082] Height of steel strand storage space The calculation formula is:

[0083] ;

[0084] In the formula, The installation height of the anchor relative to the top of the main beam 2. The exposed length of the tensioning end of the steel strand. This is the minimum storage radius for steel strands. This is the arrangement coefficient. The diameter of the steel strand. The number of layers in the steel strand storage reel;

[0085] ;

[0086] In the formula, This refers to the total number of steel strands collected in coils.

[0087] Installation height of hinge The calculation formula is:

[0088] ;

[0089] In the formula, The mounting height of the hinge base. For the dimensions of the hinge, The weld seam distance of the bracket in the hinge;

[0090] Step S12, based on the lower limit height of the interface The calculation formula yields the lower limit height of the interface. ;

[0091] Step S2: Determine the upper limit height of the interface affecting the steel-concrete bridge tower 1. The upper limit condition factors are used to calculate the upper limit height of the interface. ;

[0092] Step S2 includes:

[0093] Step S21, the upper limit conditions include the lifting operation height limit. Construction jig stability limit height and construction avoidance height restrictions The structure includes a manhole or a diaphragm.

[0094] Height restrictions for hoisting operations The calculation formula is:

[0095] ;

[0096] In the formula, The height of the crane's slewing center. This refers to the actual maximum length of the crane boom. The working radius of the crane. The total height of rigging and lifting equipment. To ensure safe passage through the gap during hoisting;

[0097] Construction jig stability limit height The calculation formula is:

[0098] ;

[0099] In the formula, This is the length coefficient. For elastic modulus, The equivalent moment of inertia of the construction formwork section, Design load for the construction formwork;

[0100] Step S22: Establish the upper limit height of the interface based on the upper limit condition factors. The calculation formula:

[0101] ;

[0102] Step S23: Establish the upper limit height of the interface based on the upper limit condition factors. The calculation formula yields the upper limit height of the interface. ;

[0103] Step S3: Determine the optimal interface height of the steel-concrete bridge tower. Based on the stiffness condition factors, the optimal interface height is calculated. ;

[0104] Step S3 includes:

[0105] Step S31, stiffness condition factors include the length of the transition section of the steel upper tower column. Bending stiffness of steel tower columns Bending stiffness of concrete lower tower column and stiffness transition coefficient Stiffness transition coefficient This is an empirical constant, and it takes any value between 0.8 and 1.0 in the calculation.

[0106] Step S32: Establish the optimal interface height based on stiffness condition factors. The calculation formula:

[0107] ;

[0108] Step S33: Calculate the optimal interface height. ;

[0109] Step S4, based on the optimal interface height Interface lower limit height and the maximum height of the interface Establish the final interface location The determination rules are used to determine the final interface position. ;

[0110] In step S4, the final interface position The rules for determining it are as follows:

[0111] When the optimal interface height < Lower limit height of the interface Then, the final interface position = Lower limit height of the interface ;

[0112] When the lower limit height of the interface <Optimal Interface Height <Maximum Height of Interface> Then, the final interface position =Optimal interface height ;

[0113] When the optimal interface height > Maximum height of the interface Then, the final interface position =Maximum height of the interface ;

[0114] The calculated optimal interface height Interface lower limit height and the maximum height of the interface The value is substituted into the determination rule and judged. Based on the judgment result, the final interface position is output. .

[0115] Example 2:

[0116] Taking the steel-concrete bridge tower 1 with a main span of 170m and a side span of 90m as a calculation example, the interface of the steel-concrete bridge tower 1 is calculated, and the design elevation of the top of the main beam 2 is set as the reference zero point.

[0117] Determine the lower limit height of the interface affecting the steel-concrete bridge tower 1 :

[0118] ;

[0119] Based on the design drawings, determine the height of the steel-concrete composite interface relative to the top of the main beam 2 in the steel-concrete composite section 12. The elevation of the steel-concrete interface is 5.0m, and the interface must be higher than this position.

[0120] The impact height of de-icing agent splash is calculated using the formula for calculating the splash height of de-icing agent. :

[0121] ;

[0122] The height of the projectiles on the surface of the guardrail The formula for calculation is:

[0123] ;

[0124] Projectile height on the surface of the reinforced concrete bridge tower 1 The formula for calculation is:

[0125] ;

[0126] Height of guardrail Vehicle speed s, wheel splash projection angle =45°, then gravitational acceleration ;

[0127] Under two-lane conditions: Horizontal distance from the wheel splash point to the oncoming side of the guardrail The scope is: ; Horizontal distance from the point of wheel splash to the oncoming side of the bridge tower The scope is: ;

[0128] Calculate the critical point and obtain the result when When the distance is greater than 1.15m, the flying debris will cross the guardrail.

[0129] ;

[0130] The height of the wheel splash increases monotonically with increasing distance. =7.5m to calculate the maximum value:

[0131] ;

[0132] The required welding space for the steel upper tower column 13 after rotation is relative to the height of the top of the main beam 2. A depth of 2.0m is selected to ensure sufficient operating space;

[0133] The height of the hinge installed on the concrete lower tower column 11 relative to the top of the main beam 2 It needs to be located at the bottom of the split screen;

[0134] Installation height of hinge base The length is 4.7m; the dimensions of the hinge It is 0.5m; the edge distance of the weld seam of the hinge bracket is 0.5m. If the height is 0.3m, then the height of the hinge relative to the top of the main beam 2 is... :

[0135] ;

[0136] Calculate the height of the steel strand storage space ;

[0137] Installation height of anchorage relative to the top of main beam 2 The exposed length of the tensioning end of the steel strand is 3.1m. The diameter of the steel strand is 0.8m. The length is 0.0152m, and the number of layers in the steel strand storage reel is [not specified]. It is 4;

[0138] Based on the total number of steel strand coils collected. Minimum storage radius of steel strand To determine the minimum storage radius of the steel strand The height of the steel strand storage space. :

[0139] ;

[0140] The lower limit height of the interface for:

[0141] ;

[0142] Calculate the upper limit height of the interface ;

[0143] Height restrictions for hoisting operations t The calculation formula is:

[0144] ;

[0145] Crane slewing center height The actual maximum length of the crane boom is 2.0m. The working radius of the crane is 45.0m. The total height of the rigging and lifting equipment is 18.0m. The safe clearance for hoisting and lifting is 1.5m. It is 1.0m;

[0146] Substituting the values ​​into the calculation, the lifting operation limit height is obtained. ;

[0147] Construction jig stability limit height The calculation formula is:

[0148] ;

[0149] In the formula, the length coefficient The elastic modulus is 0.7. 2.06×10 5 MPa, equivalent moment of inertia of the construction jig cross section 8.5×10 9 mm 4 Design load of construction formwork 2.5×10 7 N;

[0150] Substituting the values ​​into the calculation, the stability limit height of the construction jig is obtained. ;

[0151] Construction of obstacle avoidance height restriction ;

[0152] The upper limit height of the interface ;

[0153] Considering stiffness transition coefficient Establish the optimal interface height The calculation formula:

[0154] ;

[0155] In the formula, the length of the transition section of the steel upper tower column 13 is... The bending stiffness of the 13 steel upper tower column is 2.0m. 4.5× N•m², bending stiffness of concrete lower tower column 11 8.5× N•m², stiffness transition coefficient It is 0.8;

[0156] Optimal interface height ;

[0157] Final interface location The rules for determining it are as follows:

[0158] When the optimal interface height < Lower limit height of the interface Then, the final interface position = Lower limit height of the interface ;

[0159] When the lower limit height of the interface <Optimal Interface Height <Maximum Height of Interface> Then, the final interface position =Optimal interface height ;

[0160] When the optimal interface height > Maximum height of the interface Then, the final interface position =Maximum height of the interface ;

[0161] The calculated optimal interface height Interface lower limit height and the maximum height of the interface The value is substituted into the determination rule and judged. Based on the judgment result, the final interface position is output. ;

[0162] Lower limit height of the interface (5.52m)≤Optimal interface height ≤ Upper limit height of the interface (18.4m);

[0163] Therefore, the final interface position =Optimal interface height =6.36m;

[0164] The optimal interface location for the bridge rotation construction is recommended to be at a bridge deck elevation of 6.36m.

[0165] The above are merely preferred embodiments of the present invention and are illustrative in nature, not restrictive. Those skilled in the art will understand that many changes, modifications, and even equivalents can be made within the spirit and scope defined by the claims of the present invention, all of which will fall within the protection scope of the present invention.

Claims

1. A method for designing the interface position of a vertical rotation connection structure for a steel-concrete bridge tower, characterized in that, Includes the following steps: Step S1: Determine the lower limit height of the interface affecting the steel-concrete bridge tower. The lower limit condition factors are used to calculate the lower limit height of the interface. ; Step S1 includes: Step S11: The steel-concrete bridge tower includes a lower concrete tower column, a steel-concrete composite section, an upper steel tower column, and a main beam. The connection surface between the steel-concrete composite section and the upper steel tower column is the interface of the steel-concrete bridge tower. The lower limit condition factors include: the height of the steel-concrete composite interface in the steel-concrete composite section relative to the top of the main beam. The required welding space for the steel upper tower column after rotation is relative to the height of the top of the main beam. The height of the hinge installed on the concrete lower tower column relative to the top of the main beam The height of the steel strand storage space within the steel-concrete composite section relative to the top of the main beam. De-icing agent splash affects altitude ; Establish the lower limit height of the interface based on lower limit conditions. The calculation formula: ； Step S12, based on the lower limit height of the interface The calculation formula yields the lower limit height of the interface. ; Step S2: Determine the upper limit height of the interface affecting the steel-concrete bridge tower. The upper limit condition factors are used to calculate the upper limit height of the interface. ; Step S2 includes: Step S21, the upper limit condition factors include the lifting operation height limit. Construction jig stability limit height and construction avoidance height restrictions The structure includes a perforation or a diaphragm. Step S22: Establish the upper limit height of the interface based on the upper limit condition factors. The calculation formula: ； Step S23: Establish the upper limit height of the interface based on the upper limit condition factors. The calculation formula yields the upper limit height of the interface. ; Step S3: Determine the optimal interface height of the steel-concrete bridge tower. Based on the stiffness condition factors, the optimal interface height is calculated. ; Step S3 includes: Step S31, the stiffness condition factors include the length of the transition section of the steel upper tower column. Bending stiffness of steel tower columns Bending stiffness of concrete lower tower column and stiffness transition coefficient Stiffness transition coefficient This is an empirical constant, and it takes any value between 0.8 and 1.0 in the calculation. Step S32: Establish the optimal interface height based on stiffness condition factors. The calculation formula: ； Step S33: Calculate the optimal interface height. ; Step S4, based on the optimal interface height Interface lower limit height and the maximum height of the interface Establish the final interface location The determination rules are used to determine the final interface position. ; In step S4, the final interface position The rules for determining it are as follows: When the optimal interface height < Lower limit height of the interface Then, the final interface position = Lower limit height of the interface ; When the lower limit height of the interface <Optimal Interface Height <Maximum Height of Interface> Then, the final interface position =Optimal interface height ; When the optimal interface height > Maximum height of the interface Then, the final interface position =Maximum height of the interface ; The calculated optimal interface height Interface lower limit height and the maximum height of the interface The value is substituted into the determination rule and judged. Based on the judgment result, the final interface position is output. .

2. The interface position design method for the vertical rotation connection structure of a steel-concrete bridge tower as described in claim 1, characterized in that, In step S11, a crash barrier is installed on the main beam. When the de-icing agent is compressed, it forms splashes, which affect the height of the de-icing agent. The calculation formula is: ； In the formula, For the height of the crash barrier, The projectile height of the debris on the guardrail surface. The projectile height of the projectile on the surface of the reinforced concrete bridge tower. This is a correction factor; The height of the projectiles on the surface of the guardrail The formula for calculation is: ； In the formula, The horizontal distance from the point of wheel splash to the oncoming side of the crash barrier. For vehicle speed, For the wheel splash projection angle, It is the acceleration due to gravity; The projection height of the spatter on the surface of the reinforced concrete bridge tower The formula for calculation is: ； In the formula, The horizontal distance from the point of wheel splash to the oncoming side of the bridge tower.

3. The interface position design method for the vertical rotation connection structure of a steel-concrete bridge tower as described in claim 1, characterized in that, In step S11, the height of the steel strand storage space The calculation formula is: ； In the formula, The installation height of the anchor relative to the top of the main beam. The exposed length of the tensioning end of the steel strand. This is the minimum storage radius for steel strands. This is the arrangement coefficient. The diameter of the steel strand. The number of layers in the steel strand storage reel; ； In the formula, This refers to the total number of strands in the coil for storing steel strands.

4. The interface position design method for the vertical rotation connection structure of a steel-concrete bridge tower as described in claim 1, characterized in that, In step S11, the installation height of the hinge The calculation formula is: ； In the formula, The mounting height of the hinge base. For the dimensions of the hinge, This refers to the weld seam distance of the bracket in the hinge.

5. The interface position design method for the vertical rotation connection structure of a steel-concrete bridge tower as described in claim 1, characterized in that, In step S21, the hoisting operation height is limited. The calculation formula is: ； In the formula, The height of the crane's slewing center. This refers to the actual maximum length of the crane boom. The working radius of the crane. The total height of rigging and lifting equipment. To ensure safe passage through the gap during hoisting and lifting.

6. The interface position design method for the vertical rotation connection structure of a steel-concrete bridge tower as described in claim 1, characterized in that, In step S21, the stability limit height of the construction jig is... The calculation formula is: ； In the formula, This is the length coefficient. For elastic modulus, The equivalent moment of inertia of the construction formwork section, The design load for the construction formwork.

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