Construction method for assembly type hoisting of hyperbolic vase-shaped pier column

Abstract

The invention discloses a construction method for assembly type hoisting of a hyperbolic vase-shaped pier column in the technical field of bridge engineering, and the construction method comprises the following steps: S1, calculating a hyperbolic offset coefficient according to a pier column design drawing, obtaining a gravity center offset, and obtaining a hoisting point center positioning point on the top surface of the pier column; s2, according to the hoisting point center positioning point, the positions of all hoisting ring preset holes are determined, and the hoisting ring preset holes are distributed at equal intervals in a surrounding mode with the hoisting point center positioning point as the center; s3, a pier column is prepared, and holes are reserved in the top face of the pier column according to the positions of the lifting ring preset holes during preparation; s4, according to actually-measured skirt body parameters of the pier column, lifting point correction is carried out, and a lifting ring is positioned and installed according to a correction result; and S5, the pier column is hoisted, and bottom face butt joint is completed. According to the construction method, according to the design size, the center-of-gravity shift position is accurately positioned through the hyperbolic shift coefficient, and then high-level-precision hoisting point construction of the butt joint face of the fabricated bridge pier column is guaranteed through hoisting point correction.

Description

Technical Field

[0001] The present invention relates to the technical field of bridge engineering, and in particular to a construction method for assembling and hoisting a hyperbolic vase-shaped pier. Background Art

[0002] As a green and smart construction technology that is strongly supported and promoted by national policies, prefabricated technology is widely used in civil engineering fields such as bridges. This technology refers to transferring a large amount of on-site pouring work in traditional construction methods to factories. Bridge piers, box beams and other components processed and manufactured in factories are transported to the construction site and assembled and installed on site through reliable connection methods. Prefabricated technology has the following advantages: (1) industrial advantages such as standardization, factory production, and componentization; (2) significant environmental advantages, greatly reducing dust pollution, wastewater and exhaust gas pollution at construction sites; (3) greatly reducing on-site construction cycles, alleviating urban operation pressure caused by "long-term construction sites"; (4) improving the attractiveness of labor employment and realizing a new industrial model from "construction sites" to "factories".

[0003] However, because prefabricated construction requires precise docking through grouting sleeves and other methods, high construction precision control is required. For example, bridge piers may have dozens of joint steel bars on the base connection surface, and the typical tolerance is only ±2mm. This is particularly true for the hyperbolic vase-shaped bridge piers commonly used in engineering projects. The hyperbolic structure causes an offset between the center of gravity of the structure and the center of the hanging point. Failure to accurately locate this offset can result in sleeve docking failures, bent steel bars, and uneven grouting, seriously impacting project quality and safety.

[0004] At present, the existing control technologies and methods mainly include: (1) the method of combining manual experience to judge the lifting point and on-site adjustment. This method has insufficient horizontal precision control during the docking process, and most piers cannot be docked. Some piers may be able to complete the docking due to their small hyperbolic curvature, but it will also cause problems such as bending of steel bars and uneven grouting. The bending of steel bars in sleeve docking is an erroneous operation that violates relevant engineering standards and should be prohibited. (2) The method of multiple attempts and resetting the lifting point on site. This method can complete the lifting, but it requires multiple attempts and reinstallation of the lifting point. After the attempt to lift and dock is unsuccessful, the lifting point is adjusted again according to the horizontal tilt angle until it is successfully completed. This type of method often requires 3-5 adjustments for one lifting, which is time-consuming and labor-intensive, causing great waste of construction period and crane shifts. The above method is prone to multiple rework, cost waste, and reduced quality of the pier connection parts, and is prone to illegal operations. In addition, even in a bridge project, more than ten types of piers with different hyperbolic curvatures and heights are often involved. Therefore, it is difficult to form experience summaries using the above method, which seriously affects the efficiency of prefabricated construction. Summary of the Invention

[0005] This application solves the problem in the prior art that hyperbolic vase-shaped piers are difficult to complete or easily lead to engineering quality defects during assembly docking by providing a construction method for assembled hoisting of hyperbolic vase-shaped piers. It realizes the rapid hoisting and assembly of hyperbolic vase-shaped piers, and has the advantages of accurate positioning, efficient construction, and wide applicability.

[0006] The present application provides a method for assembling and hoisting a hyperbolic vase-shaped pier, comprising the following steps:

[0007] S1: Calculate the hyperbolic offset coefficient according to the pier design drawing, obtain the center of gravity offset, and obtain the center positioning point of the hanging point on the top surface of the pier;

[0008] S2: determining the positions of the preset holes of each lifting ring according to the central positioning point of the lifting point, wherein the preset holes of the lifting ring are distributed at equal intervals around the central positioning point of the lifting point;

[0009] S3: preparing the pier column, and reserving holes on the top surface of the pier column according to the preset hole positions of the respective lifting rings;

[0010] S4: Correct the hanging point according to the measured skirt parameters of the pier column, and locate and install the lifting ring according to the correction result;

[0011] S5: hoist the pier columns and complete the bottom surface docking.

[0012] The beneficial effect of the above embodiment is that the construction method accurately locates the center of gravity offset position according to the design size through the hyperbolic offset coefficient, and then corrects the lifting point to ensure high-precision lifting point construction of the docking surface of the prefabricated bridge pier.

[0013] Based on the above embodiments, the present application can be further improved as follows:

[0014] In one embodiment of the present application, in step S1, the hyperbolic shift coefficient is calculated as follows:

[0015] C x =0.25(l a1 +l a2 )(l b1 +l b2 )h2 / [l a1 l b1 h 1+ 0.25(l a1 +l a2 )(l b1 +l b2 )h2];

[0016] Among them, C xis the hyperbolic offset coefficient, h1 is the height of the straight section of the pier, and h2 is the height of the curved section of the pier; l a1 is the width of the straight segment of the pier along the X axis, l a2 is the width of the top surface of the pier along the X axis, l b1 is the width of the straight segment of the pier column along the Y axis, l b2 Beneficial Effect: This formula comprehensively considers the height and width parameters of the straight and curved sections of the pier, ensuring that the theoretical calculation of the center of gravity offset is highly consistent with the actual center of gravity of the structure, avoiding errors caused by manual estimation based on experience, providing a reliable basis for subsequent lifting point positioning, and significantly improving the accuracy of the initial positioning of the lifting.

[0017] In one embodiment of the present application, in step S1, the center of gravity offset is calculated as follows:

[0018]

[0019] Among them, d x R is the offset of the center of gravity of the lifting point on the X axis, a1 The inner arc radius along the X-axis direction. Beneficial Effects: This solves the problem of difficult-to-quantify center of gravity offset due to the hyperbolic structure of hyperbolic vase-shaped piers, ensuring that the lifting point position matches the actual center of gravity, and avoiding tilting or docking failure caused by center of gravity deviation during the lifting process.

[0020] In one embodiment of the present application, in step S2, the distance between the center of the preset hole of the lifting ring and the center positioning point of the lifting point is k, which is calculated as follows:

[0021] k=1 / 4×(l a2 +l b2 Beneficial Effect: A formula determines the distribution radius of the pre-set holes for the lifting rings, ensuring they are evenly distributed around the center of the lifting point, creating a stable multi-point lifting layout. This design disperses lifting stress, preventing localized stress concentration that can cause cracking in the concrete on the pier top surface. It also provides a reference for subsequent lifting point adjustments, streamlining the construction process.

[0022] In one embodiment of the present application, in step S4, the lifting point correction is specifically:

[0023] Taking the center of the preset hole of the lifting ring as the starting point, move t along the negative direction of the x-axis x is the center point of the lifting ring, t x To correct the distance, the calculation formula is as follows:

[0024] t x =(l a1 +l a2 )l a2 b f hf / 2l a1 l b1 h1. Beneficial effect: By introducing the measured skirt parameters (h f 、b f ) to correct the position of the lifting ring and use the formula to calculate the correction distance (t x ) to eliminate the impact of machining errors on the center of gravity caused by the pier's skirt. This correction method dynamically adjusts the lifting point position, ensuring precise alignment between the pier's bottom surface and the base during installation. This reduces the need for multiple adjustments due to skirt deviations and increases the success rate of a first-time installation.

[0025] In one embodiment of the present application, in step S5, when hoisting the pier, the selection of the hoisting equipment should be determined according to the following formula:

[0026] F=1.6×ρg(h1+h2)l a1 l b1 ;

[0027] F1≧0.4F;

[0028] Where F is the working load of the lifting equipment, F1 is the working load of a single hook, ρ is the density of reinforced concrete, and g is the acceleration due to gravity. Beneficial Effects: The formula determines the working load of the lifting equipment, scientifically matching the lifting equipment capacity with the actual weight of the pier. This formula comprehensively considers pier column size, concrete density, and the acceleration due to gravity, ensuring safe and reliable lifting equipment selection, avoiding lifting accidents caused by insufficient equipment load, and optimizing resource allocation and reducing equipment rental costs.

[0029] In one embodiment of the present application, in step S3, the reserved hole has a diameter of 400 ± 10 mm and a depth of 600 ± 10 mm. Beneficial Effect: Specified reserved hole diameters and depths ensure that the anchor depth and concrete bond strength meet the required loads. This standardized design prevents loose installation of the lifting ring or stress concentration caused by hole size deviations, ensuring the overall stability of the lifting ring and pier during installation and reducing construction safety hazards.

[0030] In one embodiment of the present application, in step S4, the lifting ring is made of steel with a grade of at least HPB300, and the lifting ring is embedded at a depth of at least 35 times the diameter of the steel bar. Beneficial Effect: The lifting ring is required to be made of steel with a grade of at least HPB300 and embedded at a depth of at least 35 times the diameter of the steel bar, ensuring that the lifting ring's tensile strength and anchoring performance meet regulatory requirements. By strengthening the material properties and anchoring depth, the lifting ring is effectively prevented from deforming or dislodging during the lifting process, ensuring the safety of the lifting operation. This is particularly suitable for the high-precision lifting requirements of heavy hyperbolic vase-shaped piers. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly describes the drawings required for the specific embodiments or the description of the prior art. Similar elements or parts are generally identified by similar reference numerals throughout the drawings. Elements or parts in the drawings are not necessarily drawn to scale.

[0032] Figure 1 This is a flowchart of the steps of a construction method for assembled hoisting of a hyperbolic vase-shaped pier column in an embodiment of the present application;

[0033] Figure 2 This is a schematic diagram of the front view parameters of the bridge pier design drawing in the embodiment of this application;

[0034] Figure 3 This is a side view parameter diagram of the bridge pier design drawing in the embodiment of this application;

[0035] Figure 4 This is a schematic diagram of the top view parameters of the bridge pier design drawing in the embodiment of this application;

[0036] Figure 5 This is a schematic diagram of the positions of the preset holes for the lifting rings in the embodiment of the present application;

[0037] Figure 6 Schematic diagram of parameters of the skirt at the bottom of the pier column in the embodiment of the present application;

[0038] Figure 7 Schematic diagram of the position of the center point of the lifting ring in the embodiment of the present application. DETAILED DESCRIPTION

[0039] The present invention will be further explained below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. After reading the present invention, modifications of various equivalent forms of the present invention made by those skilled in the art all fall within the scope defined by the claims attached to this application.

[0040] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0041] In the description of the present invention, it should be noted that the orientations or positional relationships indicated by terms such as "vertical" and "peripheral surface" are based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the inventive product is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0042] The embodiment of the present application solves the problem in the prior art that hyperbolic vase-shaped piers are difficult to complete or easily lead to engineering quality defects during prefabricated docking by providing a construction method for prefabricated hoisting of hyperbolic vase-shaped piers, thereby realizing rapid hoisting and assembly of hyperbolic vase-shaped piers, and having the advantages of accurate positioning, efficient construction (no need for trial and rework), and wide applicability (adaptable to different hyperbolic structures).

[0043] The technical solution in the embodiments of the present application is to solve the above problems, and the overall idea is as follows:

[0044] Example:

[0045] like Figure 1 As shown, a construction method for assembled hoisting of a hyperbolic vase-shaped pier column comprises the following steps:

[0046] S1: Calculate the hyperbolic offset coefficient according to the bridge pier design drawings, obtain the center of gravity offset, and use this to obtain the center positioning point of the hanging point on the top surface of the pier.

[0047] S1.1: Locate the geometric center of the bottom surface according to the bridge pier design drawings and mark the relevant parameters:

[0048] Positioning the centroid of the bottom surface of the hyperbolic vase-shaped pier: The bottom surface of the pier is rectangular. Combined with the pier design drawings, a coordinate system is established on the pier bottom surface drawing, with the horizontal centroid O of the bottom surface as the origin of the coordinate system, the asymmetric side as the X-axis direction, the symmetric side as the Y-axis direction, and the vertical direction as the Z-axis.

[0049] like Figure 2-4 As shown, ABCD is the bottom surface of the pier column, and A'B'C'D' is the top surface of the pier column. The height of the straight section of the pier column is h1, and the height of the curved section is h2; the radius of the inner arc in the X-axis direction is R a1 The radius of the arcs on both sides of the Y-axis is the same; the width of the straight section of the pier column along the X-axis is l a1 The width of the top surface of the pier along the X-axis is l a2 The width of the straight section of the pier column along the Y axis is l b1 The width of the top surface of the pier along the Y axis is l b2 .

[0050] S1.2: Calculate the hyperbolic offset coefficient of the center of gravity on the X-axis based on the horizontal centroid O of the bottom surface:

[0051] Apply the principle of plane eccentricity to establish the hyperbolic offset coefficient C x Calculation formula: C x =0.25(l a1 +l a2 )(l b1 +l b2 )h2 / [l a1 lb1 h 1+ 0.25(l a1 +l a2 )(l b1 +l b2 )h2] (1);

[0052] The hyperbolic offset coefficient is further explained as follows:

[0053] Due to the hyperbolic shape, the center of gravity of the bridge pier is offset from the center of its bottom surface. In order to determine the center of gravity and hanging point of the hyperbolic vase-shaped bridge pier, the ratio of its offset to the pier body size is the hyperbolic offset coefficient.

[0054] S1.3: According to the hyperbolic deviation coefficient C x Calculate the center of gravity offset and obtain the center positioning point of the hanging point on the top surface of the pier:

[0055] The offset d of the center of gravity of the hanging point on the X axis is obtained by the hyperbolic offset coefficient x :

[0056]

[0057] Since the pier is symmetrical on the Y axis, the offset d on the Y axis is y is 0;

[0058] The center positioning point of the hanging point on the top of the pier column is O x (d x , 0).

[0059] In step S1, the hyperbolic shift coefficient (C x ) and the center of gravity offset (d x ) to transform complex asymmetric structural parameters into actionable lifting point positioning data. This method is applicable to hyperbolic piers of varying curvature, height, and width. Its versatility and computational efficiency allow for rapid generation of lifting plans for a variety of pier types, significantly improving construction standardization.

[0060] S2: Determine the positions of the four preset holes for the lifting rings. The preset holes for the lifting rings are equidistantly distributed around the central positioning point of the lifting point.

[0061] like Figure 5 As shown, according to the center positioning point O x (d x , 0), set the preset holes of the lifting ring at equal distances along the positive and negative directions of the X and Y axes. The distance k between the center of the preset hole of the lifting ring and the center positioning point of the lifting point is calculated as follows:

[0062] k=1 / 4×(l a2 +l b2 ) (3);

[0063] The preset hole positions of each lifting ring are calculated based on the distance k.

[0064] S3: Prepare the pier according to the pier design drawings, and reserve holes on the top surface of the pier according to the preset hole positions of each lifting ring during preparation.

[0065] The pier preparation process is as follows:

[0066] S3.1: Assemble the pier column formwork and complete the installation of the pier column reinforcement cage: (Same as the conventional steps for prefabricated piers) Assemble the pier column steel formwork, guide the pier column reinforcement cage into the formwork, and complete the fixation;

[0067] S3.2: Based on the preset hole positions of the four lifting rings, use a temporary template to reserve a hole with a diameter of 400 ± 10 mm and a depth of 600 ± 10 mm on the top surface of the pier;

[0068] S3.3: Concrete pouring, concrete curing, and formwork removal: (Same as the conventional steps for prefabricated piers) Complete the concrete pouring and remove the formwork after curing for the specified time.

[0069] S4: According to the measured skirt parameters after pier column curing, the hanging points are corrected, and the lifting rings are located and installed according to the correction results.

[0070] Since the skirt at the bottom of the pier column has no effect on the design load, in many actual engineering operations, it is carried out according to the existing template of the project, which causes uncertain variables in the positioning of the center of gravity. Therefore, this effect is eliminated through actual measurement correction.

[0071] S4.1: If Figure 6-7 As shown, obtain the actual measurement value of the skirt height at the bottom of the pier column, including the skirt height h f 、Pier skirt width b f , to correct the hanging point:

[0072] Based on the preset hole center of the lifting ring, move t in the negative direction of the x-axis x The center point of the lifting ring is the same as the center point of the four lifting rings. x It is the correction distance from the center of the preset hole of the lifting ring to the negative direction of the X axis. The calculation formula is as follows:

[0073] t x =(l a1 +l a2 )l a2 b f h f / 2l a1 l b1 h1 (4);

[0074] S4.2: Position, install, and anchor the lifting rings according to the corrected center point positions of the lifting rings.

[0075] Among them, the lifting ring is made of steel, the grade should not be lower than HPB300, the steel bar diameter should not be less than 32mm, and the embedded depth should not be less than 35 times the steel bar diameter (35d).

[0076] S5: Hoist the pier columns and complete the bottom surface docking.

[0077] After the anchor curing time of the lifting ring is reached, the pier column is hoisted. The base slab surface is slurried with a thickness of 20mm. The lifting equipment is connected to the lifting rings. During the hoisting process, the bottom surface of the pier column is aligned with the length of each side of the base. Through adjustment, the sleeve docking process is controlled, and the protruding steel bars of the base are inserted into the sleeve at the bottom of the pier column. After the sleeve docking is completed, cement mortar is grouting in the reserved grouting holes. Other work is completed according to relevant construction standards and steps until the pier column installation is completed.

[0078] Among them, the selection of lifting equipment should be determined according to the following formula:

[0079] F=1.6×ρg(h1+h2)l a1 l b1 (5);

[0080] F1≧0.4F(6);

[0081] Among them, F is the working load of the lifting equipment, F1 is the working load of a single hook, and the corresponding working loads of the selected lifting equipment and hook should be at least greater than the corresponding values of F and F1; ρ is the density of reinforced concrete, which is generally taken as 2500kg / m 3 , g is the acceleration due to gravity, which is 9.8N / kg.

[0082] The technical solutions in the above embodiments of the present application have at least the following technical effects or advantages:

[0083] (1) Hyperbolic vase-shaped bridge piers have a complex shape that makes it difficult to locate the center of gravity. However, this construction method uses the hyperbolic offset coefficient to accurately locate the center of gravity offset according to the design dimensions, thereby ensuring high-precision lifting and hoisting point construction of the assembled docking surface.

[0084] (2) Hyperbolic vase-shaped bridge piers vary in their specific dimensions, such as curve height, inner and outer curve radii, and so on. Even within the same bridge project, there are often multiple piers with different hyperbolic parameters. Positioning them one by one would be labor-intensive and prone to errors. This construction method, however, uses the hyperbolic offset coefficient to substitute the hyperbolic parameters of different piers into the calculation to obtain their respective center of gravity offsets. This method is easy to apply in engineering, and the resulting results are standardized and standardized.

[0085] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A construction method for the assembled hoisting of a hyperbolic vase-shaped pier, characterized in that: The following steps are involved: S1: Calculate the hyperbolic offset coefficient according to the pier design drawing, obtain the center of gravity offset, and obtain the center positioning point of the hanging point on the top surface of the pier; S2: determining the positions of the preset holes of each lifting ring according to the central positioning point of the lifting point, wherein the preset holes of the lifting ring are distributed at equal intervals around the central positioning point of the lifting point; S3: preparing the pier column, and reserving holes on the top surface of the pier column according to the preset hole positions of the respective lifting rings; S4: Correct the hanging point according to the measured skirt parameters of the pier column, and locate and install the lifting ring according to the correction result; S5: hoist the pier columns and complete the bottom surface docking.

2. The construction method according to claim 1, characterized in that: In step S1, the hyperbolic shift coefficient is calculated as follows: C x =0.25(l a1 +l a2 )(l b1 +l b2 )h2 / [l a1 l b1 h 1+ 0.25(l a1 +l a2 )(l b1 +l b2 )h2]; Among them, C x is the hyperbolic offset coefficient, h1 is the height of the straight section of the pier, and h2 is the height of the curved section of the pier; l a1 is the width of the straight segment of the pier along the X axis, l a2 is the width of the top surface of the pier along the X axis, l b1 is the width of the straight segment of the pier column along the Y axis, l b2 It is the width of the top surface of the pier along the Y axis.

3. The construction method according to claim 2, characterized in that: In step S1, the center of gravity offset is calculated as follows: Among them, d x R is the offset of the center of gravity of the lifting point on the X axis, a1 is the inner arc radius along the X-axis.

4. The construction method according to claim 1, characterized in that: In step S2, the distance between the center of the preset hole of the lifting ring and the center positioning point of the lifting point is k, which is calculated as follows: k＝1 / 4×(l a2 +l b2 )。 5. The construction method according to claim 1, characterized in that: In step S4, the lifting point correction is specifically as follows: starting from the center of the preset hole of the lifting ring, move t in the negative direction of the x-axis x is the center point of the lifting ring, t x To correct the distance, the calculation formula is as follows: t x =(l a1 +l a2 )L a2 b f h f / 2l a1 L b1 h1.

6. The construction method according to claim 1, characterized in that: In step S5, when hoisting the pier column, the hoisting equipment selection should be determined according to the following formula: F=1.6×ρg(h1+h2)l a1 the b1 ; F1≧0.4F; Wherein, F is the working load of the lifting equipment, F1 is the working load of a single hook, ρ is the density of reinforced concrete, and g is the acceleration of gravity.

7. The construction method according to claim 1, characterized in that: In step S3, the diameter of the hole is 400±10 mm and the depth is 600±10 mm.

8. The construction method according to claim 1, characterized in that: In step S4, the lifting ring is made of steel with a grade not lower than HPB300, and the embedding depth of the lifting ring is not lower than 35 times the diameter of the steel bar.

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