Small box girder erection structure and small box girder erection method

Abstract

The present invention discloses a small box girder erection structure and a small box girder erection method, which relate to the technical field of bridge structures. The structure is erected on a cap beam, and comprises: a small box girder body, a wedge-shaped pad, a plate-type rubber bearing and a supporting pad stone; the supporting pad stone is arranged on the beam shoulder of the cap beam; the plate-type rubber bearing is arranged on the top of the supporting pad stone; the wedge-shaped pad is arranged on the top of the plate-type rubber bearing; the end of the bottom surface of the small box girder body is in abutment with the top of the wedge-shaped pad. The present invention can achieve the technical effect of convenient and simple erection and adjustment of the small box girder.

Description

Technical Field

[0001] The present invention relates to the technical field of bridge structures, and more particularly to a small box girder erection structure and a small box girder erection method. Background Art

[0002] At present, the control method adopted for the erection of prefabricated prestressed reinforced concrete small box girders (hereinafter referred to as prefabricated small box girders) designed for inverted T-shaped cap beams in China, which only realize the continuous end of the beam body through the wet joint of the top plate at the continuous end of the post-cast beam body, is the centerline control method. The specific method is as follows: before the erection of the prefabricated small box girder, the centerline of the bottom plate and the centerline of the support of the beam body are found, and then the centerline of the top plate is determined by the theodolite threading method based on the centerline of the bottom plate as the reference. During the erection, the lateral position of the beam body is controlled by aligning the centerline of the top plates at both ends of the beam body with the corresponding design centerline determined by measuring and setting out the top surface of the cap beam, and then the longitudinal position of the beam body is controlled by aligning the centerline of the bottom plate support with the centerline of the pad stone support.

[0003] This method has shortcomings and deficiencies: when the beam is erected, the bottom plate needs to be aligned with the aid of climbing equipment or an operating frame for technicians to conduct high-altitude measurement and positioning, which increases the operation risk and construction investment; and due to the structural characteristics of the inverted T-shaped cap beam, the top plate of the (non-)continuous end of the beam is cantilevered for a certain length, and the beam end is a non-continuous surface. The center line of the bottom plate of the beam cannot be directly determined by the plumb line to determine the center line of the top plate, and it needs to be determined by theodolite measurement and setting out. For curved bridges, when erecting and installing small box girders, the correction of the center line of the beam body after the curved beam body is rotated must be considered, which places high requirements on the measurement and adjustment of personnel and is inconvenient to operate.

[0004] Therefore, how to provide a structure and method that can realize convenient and simple installation and adjustment of small box girders is one of the technical problems that urgently need to be solved in this field. Summary of the invention

[0005] In view of this, the present invention provides a small box girder erection structure and a small box girder erection method, the purpose of which is to solve the above-mentioned deficiencies.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0007] A small box beam erection structure is erected on a cap beam, and comprises: a small box beam body, a wedge-shaped pad, a plate-type rubber bearing and a supporting pad stone; the supporting pad stone is arranged on the beam shoulder of the cap beam; the plate-type rubber bearing is arranged on the top of the supporting pad stone; the wedge-shaped pad is arranged on the top of the plate-type rubber bearing; the end of the bottom surface of the small box beam body is in contact with the top of the wedge-shaped pad.

[0008] Preferably, a beam frame is provided at the top end of the cap beam.

[0009] Preferably, the bottom end of the cap beam is fixedly connected to a pier.

[0010] A small box girder erection method is implemented using the above-mentioned small box girder erection structure, comprising the following steps:

[0011] S1. Measure and verify the position deviation of the embedded steel plate of the small box girder body end support to determine its deviation value; measure and set out at the top of the cap beam, remeasure the longitudinal or transverse center line of the supporting cushion stone, measure and determine the side elevation position and verticality deviation of the cap beam, and modify the design value according to the measured deviation value;

[0012] S2. Make a measuring ruler for the intersection angle between the bottom plate and the web of the small box girder body. A steel nail is fixed at the intersection of the inner wall of the measuring ruler. The steel nail is perpendicular to the ruler surface and is used to accurately determine the intersection position when measuring with the steel ruler. The angle of the measuring ruler is determined according to the slope of the web of the small box girder body.

[0013] S3. Lift the small box girder body to the position where the top beam of the cap beam is arranged, and keep the bottom of the small box girder body away from the top surface of the wedge-shaped pad. Use a steel ruler to measure the horizontal distance between the transverse center line lead-out line of the bottom support of the small box girder body and the side elevation of the cap beam at the end of the beam, adjust and control the longitudinal displacement of the small box girder body and make the correction value consistent. Then, simultaneously drop the beam body by 20cm at both ends of the small box girder body. Use the two inner edges of the measuring ruler to fit tightly against the bottom plate and the side of the web of the small box girder body, and find the intersection of the bottom plate of the small box girder body and the outer edge line of the web. Use a steel ruler to measure the horizontal distance from the intersection to the center line of the adjacent small box girder body support to adjust the horizontal position of the positioning beam body, continue to drop the beam body to the support, and then verify that the longitudinal and transverse control dimensions of the beam body are correct and complete the installation of the small box girder body.

[0014] Preferably, the measuring ruler in step S2 is made by cutting a hard plastic plate with a thickness of 5 mm to 8 mm.

[0015] Preferably, in step S3, the small box girder body is lifted to the cap beam top beam arrangement position by ground lifting equipment or a bridge erection machine, and a clearance height of 30 cm between the bottom of the small box girder body and the top surface of the wedge-shaped pad is maintained.

[0016] Compared with the prior art, the present invention has achieved the following technical effects:

[0017] The wedge-shaped pad is arranged between the small box beam body and the plate rubber bearing. The installation of the small box beam body can be conveniently adjusted by adjusting the wedge-shaped pad; and a beam frame is provided at the end of the top surface of the cap beam, which is conducive to ensuring the stability of the top surface of the cap beam. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the transverse positioning and installation of a small box girder body of a small box girder erection structure of the present invention;

[0019] Figure 2It is a schematic diagram of the longitudinal positioning and installation of a small box girder body of a small box girder erection structure of the present invention;

[0020] Figure 3 A schematic diagram of a measuring ruler structure of a small box girder erection structure of the present invention;

[0021] Figure 4 A schematic diagram of the rotation of a small box girder body of a small box girder erection structure of the present invention;

[0022] Figure 5 It is a schematic diagram of the transverse installation and positioning of a small box beam erection structure of the present invention when the small box beam body does not rotate;

[0023] Figure 6 It is a schematic diagram of the lateral installation and positioning of a small box girder body of a small box girder erection structure of the present invention when it rotates;

[0024] In the figure:

[0025] 1- cap beam; 2- small box beam body; 3- wedge-shaped pad; 4- plate rubber bearing; 5- supporting cushion stone; 6- pier column; 7- measuring ruler; 71- steel nail. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] Example

[0028] Reference Figure 1-6 A small box beam erection structure is shown, which is erected on a cap beam 1, and includes: a plurality of small box beam bodies 2, a plurality of wedge-shaped pads 3, a plurality of plate-type rubber bearings 4, and a plurality of supporting pads 5. A wedge-shaped pad 3 is provided on the bottom surface of each small box beam body 2, and a plate-type rubber bearing 4 is provided at both ends of the bottom surface of the wedge-shaped pad 3, and a supporting pad 5 is provided on the bottom surface of the plate-type rubber bearing 4, and the supporting pad 5 is arranged on the beam shoulder of the cap beam 1. The wedge-shaped pad 3 is provided to facilitate the subsequent adjustment of the small box beam body 2.

[0029] In this embodiment, a beam frame 11 is provided at the top end of the cap beam 1 .

[0030] In this embodiment, a pier 6 is fixedly connected to the bottom end of the cap beam 1 .

[0031] The invention also discloses a method for erecting a small box beam, comprising the following steps:

[0032] S1. Measure and verify the position deviation of the embedded steel plate of the beam end support of the small box girder body 2 to determine its deviation value; measure and set out at the top of the cap beam 1, remeasure the longitudinal or transverse center line of the supporting cushion stone 5, measure and determine the side elevation position and verticality deviation of the cap beam 1, and modify the design value according to the measured deviation value;

[0033] In the present embodiment, the top surfaces of multiple small box girder bodies 2 constitute the bridge deck. Corresponding to the setting of the transverse slope of the bridge deck, the installation methods of the small box girder bodies 2 are divided into the following three cases: ① The top surface of the cap beam 1 is a horizontal plane, and multiple small box girder bodies 2 are of equal height. When the small box girder body 2 is installed, the bottom plate of the small box girder body 2 is placed horizontally, and the center line of the small box girder body 2 is the reference line. After the whole span is installed, the transverse slope of the beam surface of the small box girder body 2 is immediately formed; ② The super-high gradient section, when the small box girder body 2 is installed, the small box girder body 2 rotates at a specified angle and direction with the line connecting the two end reference points as the rotation axis to adapt to the change of the transverse slope of the bridge deck. After the rotation, the bottom plate of the small box girder body 2 is tilted, and the inclination angle is the rotation angle of the small box girder body 2. After the small box girder body 2 is rotated, the reference line of the small box girder body 2 and the beam of the small box girder body 2 are aligned. The centers do not coincide, and the plumb line of the small box girder body 2 is the reference line; ③ Super-elevated section, since the top plate is set with a transverse slope of 2% when the small box girder body 2 is prefabricated, when the transverse slope of the bridge deck is the same as the transverse slope of the top surface of the small box girder body 2, the small box girder body 2 does not need to be rotated, and the bottom plate can be placed horizontally; when the transverse slope of the bridge deck is greater than or less than the transverse slope of the top surface of the small box girder body 2, the small box girder body 2 is rotated at the specified angle and direction with the line connecting the two end reference points as the rotation axis to meet the requirements of the transverse slope setting of the bridge deck. After the rotation, the bottom plate of the small box girder body 2 is tilted, and the tilt angle is the rotation angle of the small box girder body 2; After the rotation of the small box girder body 2, the reference line of the small box girder body 2 does not coincide with the center of the beam, and the plumb line of the small box girder body 2 is the reference line. This reference line is used to control the lateral position of the small box girder body 2 during installation, such as Figure 4 As shown, point P is the reference point of the small box girder body 2, L2 is the plumb line, and L3 is the center line of the small box girder body 2. Note: The cross slope is positive if the middle is high and the two sides are low on the cross section of the bridge, otherwise it is negative; the rotation angle of the small box girder body 2 is positive counterclockwise along the increasing direction of the pile number, and negative clockwise.

[0034] In this embodiment, the lateral arrangement of the small box beam body 2 is divided into two cases: the small box beam body 2 is lateral rotated according to the design specified angle and direction (counterclockwise, clockwise) and the small box beam body 2 does not rotate. The lateral positioning calculation is also slightly different, such as Figure 5 , 6 As shown, L4 is the lateral control spacing, and L5 is the rotational lateral displacement of the small box beam body 2;

[0035] When the prefabricated small box girder body 2 is erected and installed, the beam spacing is the spacing between the center lines of the adjacent small box girder bodies 2 in the transverse direction of the bridge, and the corresponding beam spacing is selected according to the standard bridge width; the bottom plate width of the small box girder body 2 is the distance between the intersections of the bottom plate and the web plate, and then the support type is selected according to the height of the small box girder body 2, and the transverse installation positioning dimensions of the prefabricated small box girder body 2 are calculated and determined according to the following table:

[0036]

[0037]

[0038] (Note: ΔL “+” or “-” in the formula is determined comprehensively according to the order of beam erection and the direction of beam rotation.)

[0039] S2. Make a measuring ruler 7 for the intersection angle between the bottom plate and the web of the small box girder body 2. A steel nail 71 is fixed at the intersection of the inner wall of the measuring ruler 7. The steel nail 71 is perpendicular to the ruler surface of the measuring ruler 7 and is used to accurately determine the intersection position when measuring with a steel ruler. The angle of the measuring ruler 7 is determined according to the slope of the web of the small box girder body 2.

[0040] The measuring ruler 7 is preferably made by cutting from a 5mm to 8mm thick hard plastic plate;

[0041] S3. Lift the small box girder body 2 to the top beam arrangement position of the cap beam 1, and keep the bottom of the small box girder body 2 away from the top surface of the wedge-shaped pad 3. Use a steel ruler to measure the horizontal distance between the transverse center line lead-out line of the bottom support of the small box girder body 2 and the side elevation of the cap beam 1 at the end of the beam, adjust and control the longitudinal displacement of the small box girder body 2 and make the correction value consistent, then simultaneously drop the beam body 2 by 20 cm at both ends of the small box girder body 2, use the two inner edges of the measuring ruler 7 to fit tightly against the bottom plate and the side of the web of the small box girder body 2, and find the intersection of the bottom plate and the outer edge line of the web of the small box girder body 2, use a steel ruler to measure the horizontal distance from the intersection to the center line of the adjacent small box girder body 2 support to adjust the horizontal position of the positioning beam body, continue to drop the beam body to the support, and then verify that the longitudinal and transverse control dimensions of the beam body are correct and complete the installation of the small box girder body 2.

[0042] The small box girder body 2 is lifted to the top beam arrangement position of the cap beam 1 by ground lifting equipment or a bridge erecting machine, and a clearance height of 30 cm is maintained between the bottom of the small box girder body 2 and the top surface of the wedge-shaped pad 3.

[0043] Beneficial effects:

[0044] When erecting the small box girder body 2, it is difficult to operate and control directly the distance between beams on site. The purpose of horizontal positioning of the beam body (beam axis) can be achieved by adopting an indirect positioning control method, that is: by controlling the distance from the intersection of the bottom plate and the web of the small box girder body 2 to the center line of the adjacent supporting pad stone 5 to achieve the horizontal positioning of the beam body (beam axis). During construction, positioning control should be performed according to the corresponding control dimensions according to the order of beam erection. The longitudinal positioning of the small box girder body 2 is to compare the measured horizontal distance from the horizontal axis of the support to the side elevation of the cap beam with the design value (425mm) and to correct the design value in combination with the actual installation position deviation of the embedded steel plate of the beam end support, so as to position and control the longitudinal installation position of the beam body with the corrected design value. When installing and positioning the small box girder body 2, the positioning sequence of "longitudinal first, then horizontal" should be followed, and the existing control line and the outer edge line of the structure should be used as the benchmark to achieve simple and efficient installation of the prefabricated small box girder body 2.

[0045] The above description is only a preferred embodiment of the present invention and does not limit the technical scope of the present invention. Therefore, any slight modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A method for erecting a small box beam structure, wherein the structure is erected on a cap beam (1), characterized in that: The structure comprises: a small box beam body (2), a wedge-shaped pad (3), a plate-type rubber bearing (4) and a supporting pad stone (5); The supporting pad stone (5) is arranged on the beam shoulder of the cap beam (1); The plate-type rubber bearing (4) is arranged on the top of the supporting cushion stone (5); The wedge-shaped pad (3) is arranged on the top end of the plate-type rubber support (4); The end of the bottom surface of the small box beam body (2) is in contact with the top of the wedge-shaped pad (3) The erection method includes the following steps: S1. Measure and verify the embedded position deviation of the pre-embedded steel plate of the beam end support of the small box beam body (2) to determine the deviation value; Measure and lay out the top of the cap beam (1), re-measure the longitudinal or transverse center line of the supporting cushion stone (5), measure and determine the side elevation position and verticality deviation of the cap beam (1), and correct the design value according to the measured deviation value; S2. A measuring ruler (7) is made for measuring the intersection angle between the bottom plate and the web of the small box girder body (2). A steel nail (71) is fixed at the intersection of the inner wall of the measuring ruler (7). The steel nail (71) is perpendicular to the ruler surface of the measuring ruler (7) and is used to accurately determine the intersection position when measuring with a steel ruler. The angle of the measuring ruler (7) is determined according to the slope of the web of the small box girder body (2); S3, lift the small box girder body (2) to the top beam arrangement position of the cap beam (1), and keep the bottom of the small box girder body (2) away from the top surface of the wedge-shaped pad (3), measure the horizontal distance between the transverse center line lead-out line of the bottom support of the small box girder body (2) and the side elevation of the cap beam (1) at the end of the beam by a steel ruler, adjust and control the longitudinal displacement of the small box girder body (2) and make the correction value coincide, then synchronously drop the beam body 20cm at both ends of the small box girder body (2), use the two inner edges of the measuring ruler (7) to fit tightly against the bottom plate and the side of the web of the small box girder body (2), and find the intersection of the bottom plate of the small box girder body (2) and the outer edge line of the web, measure the horizontal distance from the intersection to the center line of the adjacent small box girder body (2) support by a steel ruler, adjust the horizontal position of the positioning beam body, continue to drop the beam body to the support, and then verify that the longitudinal and transverse control dimensions of the beam body are correct, and complete the installation of the small box girder body (2); In step S1, the top surfaces of the plurality of small box girder bodies (2) constitute a bridge deck. Corresponding to the setting of the transverse slope of the bridge deck, the installation methods of the small box girder bodies (2) are divided into the following three situations: ① The top surface of the cap beam 1 is a horizontal surface, and the multiple small box beam bodies (2) are of equal height. When the small box beam body (2) is installed, the bottom plate of the small box beam body (2) is placed horizontally, and the center line of the small box beam body (2) is the reference line. After the entire span is installed, the cross slope of the beam surface of the small box beam body (2) is immediately formed; ② In the superelevation gradient section, when the small box girder body (2) is installed, the small box girder body (2) rotates at a specified angle and direction with the line connecting the two end reference points as the rotation axis to adapt to the change of the transverse slope of the bridge deck. After the rotation, the bottom plate of the small box girder body (2) is tilted, and the tilt angle is the rotation angle of the small box girder body (2). After the rotation of the small box girder body (2), the reference line of the small box girder body (2) does not coincide with the beam center of the small box girder body (2), and the plumb line of the small box girder body (2) is the reference line; ③ In the super-elevated section, since the top plate of the small box girder body (2) is set with a transverse slope of 2% when the small box girder body (2) is prefabricated, when the transverse slope of the bridge deck is the same as the transverse slope of the top surface of the small box girder body (2), the small box girder body (2) does not need to be rotated, and the bottom plate can be placed horizontally; when the transverse slope of the bridge deck is greater than or less than the transverse slope of the top surface of the small box girder body (2), the small box girder body (2) is rotated at the angle and direction specified by the design with the line connecting the two end reference points as the rotation axis to meet the requirements for setting the transverse slope of the bridge deck. After the rotation, the bottom plate of the small box girder body (2) is tilted, and the tilt angle is the rotation angle of the small box girder body (2); The measuring ruler (7) in step S2 is made by cutting a hard plastic plate with a thickness of 5 mm to 8 mm; In step S3, the small box girder body (2) is lifted to the top beam arrangement position of the cap beam (1) by ground lifting equipment or a bridge erection machine, and the clearance height between the bottom of the small box girder body (2) and the top surface of the wedge-shaped pad (3) is maintained at 30 cm.

2. A method for erecting a small box girder structure according to claim 1, characterized in that: A beam frame (11) is provided at the top end of the cap beam (1).

3. A method for erecting a small box beam structure according to claim 2, characterized in that: The bottom end of the cap beam (1) is fixedly connected to a pier column (6).

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