Arch bridge structure against unbalanced horizontal thrust

Abstract

The present application provides an arch bridge structure for resisting unbalanced horizontal thrust, comprising a first arch seat, a second arch seat, and a third arch seat arranged in sequence along a preset extension path of the arch bridge; the second arch seat is provided with two rows of first pairs of tie rods detachably connected thereto and extending along the longitudinal direction of the bridge; the two rows of first pairs of tie rods are arranged in layers above and below, and the two rows of first pairs of tie rods extend to and are connected to the first arch seat and the third arch seat respectively; the first arch seat and the third arch seat are each provided with a row of second pairs of tie rods extending along the longitudinal direction of the bridge and arranged in layers above and below the first pairs of tie rods; the tensioning directions of the two rows of tie rods corresponding to the same arch seat are opposite. By tensioning the tie rods before each stage of construction of the arch bridge, the unbalanced horizontal tension exerted on the arch seat during construction can be offset, thereby improving the structural stability of the arch seat; the tie rods are detachably connected to the arch seat and can be removed for turnover after the construction of the entire bridge is completed, thereby improving the efficiency of the tie rods and reducing costs.

Description

Technical Field

[0001] The present application relates to the technical field of bridge construction, and in particular to an arch bridge structure that resists unbalanced horizontal thrust. Background Art

[0002] Arch bridges are a common bridge structure with a long history. Their graceful lines, excellent mechanical properties, and superior spanning capacity have led to their widespread application in various bridge projects. In particular, with the large-scale construction of infrastructure such as highways and high-speed railways, arch bridges are increasingly favored by engineers and owners as spanning structures. These structures are being successfully applied in practical projects, achieving significant economic and social benefits.

[0003] During the construction of the arch ring and the superstructure of the existing continuous arch bridge, the arch ring arch foot will generate an unbalanced horizontal thrust on the arch seat. This unbalanced horizontal thrust will affect the stability of the arch seat and pose a great safety hazard. Summary of the Invention

[0004] The purpose of this application is to provide a structurally stable arch bridge structure that can resist unbalanced horizontal thrust.

[0005] In order to achieve the above objectives, this application provides the following technical solutions:

[0006] An arch bridge structure for resisting unbalanced horizontal thrust includes a first arch seat, a second arch seat and a third arch seat arranged in sequence along a preset extension path of the arch bridge. The second arch seat is provided with two rows of first pairs of tie rods that are detachably connected to it and extend along the longitudinal direction of the bridge. The two rows of the first pairs of tie rods are arranged in layers up and down, and the two rows of the first pairs of tie rods extend to the first arch seat and the third arch seat respectively and are connected thereto. The first arch seat and the third arch seat are each provided with a row of second pairs of tie rods that extend along the longitudinal direction of the bridge and are arranged in layers up and down with the first pair of tie rods. The tensioning directions of the two rows of tie rods corresponding to the same arch seat are opposite.

[0007] It is further provided that: the tie rod comprises a precision-rolled threaded steel bar, and its end is mounted on the arch seat through an anchor.

[0008] It is further configured that: one end of the tension rod is a tensioning end, and the other end is a fixed end;

[0009] Among them, the ends of the first pair of tie rods close to the second arch seat are the fixed ends of the first pair of tie rods, and the ends of the first pair of tie rods close to the first arch seat or the third arch seat are the tensioning ends of the first pair of tie rods; the fixed ends of the second pair of tie rods are respectively located at their ends close to the first arch seat or the third arch seat, and the second pair of tie rods are tensioned toward the second arch seat.

[0010] It is further provided that the length of the tensioning end of the tension rod exposed to the anchor is not less than 6 times the pitch of the finished rolled threaded steel bar, and the length of the fixed end exposed to the anchor is not less than 1.5 times the outer diameter of the finished rolled threaded steel bar.

[0011] It is further provided that: a nut for locking the tension rod is installed at the tensioning end of the tension rod.

[0012] Further configuration: Anchor plates are installed at both ends of the tension rod.

[0013] It is further configured that: pre-buried pipes constituting tie rod holes are embedded in the arch seats, and the pre-buried pipes in each arch seat are provided in two rows in upper and lower layers.

[0014] It is further arranged that each row of tie rod holes formed by the embedded pipes is provided with multiple ones along the transverse direction of the bridge, and the multiple tie rod holes include basic holes and reserved holes. The reserved holes are used to increase the tie rods for tensioning when the arch foot displacement and / or stress are too large.

[0015] It is further configured that: the reserved holes are provided with at least two groups, and the two groups of the reserved holes are symmetrically arranged on both sides of the basic hole.

[0016] Further configuration: the embedded pipe includes a PVC pipe.

[0017] Compared with the existing technology, the solution of this application has the following advantages:

[0018] In the arch bridge structure for resisting unbalanced horizontal thrust of the present application, the arch ring and arch foot can generate unbalanced horizontal thrust on the arch seat according to different construction stages. The tension rods are tensioned step by step before each stage of construction. This effectively offsets the unbalanced horizontal thrust generated on the arch seat during different construction stages, avoids unbalanced deformation of the arch seat during construction, and ensures the structural stability of the arch seat. Before removing the tension rods, the tension rods are gradually unloaded. This prevents unbalanced thrust on the arch seat after the tension of the tension rods is instantly unloaded, helping to maintain the structural stability of the arch seat.

[0019] Additional aspects and advantages of the present application will be given in part in the following description, which will become apparent from the following description, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0021] Figure 1 A schematic diagram of the structure of the arch bridge for resisting unbalanced horizontal thrust in this application;

[0022] Figure 2 for Figure 1A magnified schematic diagram of part A;

[0023] Figure 3 A schematic diagram of the second abutment in the arch bridge structure for resisting unbalanced horizontal thrust in the present application;

[0024] Figure 4 This is a schematic diagram of the tie rod holes on the second arch seat of the arch bridge structure for resisting unbalanced horizontal thrust in this application.

[0025] In the figure, 11, first arch seat; 12, second arch seat; 13, third arch seat; 2, arch ring; 31, first pair of tie rods; 32, second pair of tie rods; 33, tensioning end; 34, fixed end; 35, nut; 41, foundation hole; 42, reserved hole. DETAILED DESCRIPTION

[0026] The following describes in detail embodiments of the present application, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and are not to be construed as limiting the present application.

[0027] See Figures 1 to 4 The present application relates to an arch bridge structure for resisting unbalanced horizontal thrust, mainly to a double-arch bridge structure, which includes an arch seat and a tension rod detachably connected to the arch seat. By tensioning the tension rod, the unbalanced horizontal thrust exerted on the arch seat during construction can be offset to improve the stability of the arch bridge structure.

[0028] Please combine Figure 1 The arch seat includes a first arch seat 11, a second arch seat 12, and a third arch seat 13, which are arranged in sequence along the preset extension path of the arch bridge. Each arch seat is provided with two rows of tie rods arranged in layers. Specifically, the second arch seat 12 is provided with two rows of first tie rods 31 extending in the longitudinal direction of the bridge. The two rows of the first tie rods 31 are arranged in layers, and the two rows of the first tie rods 31 extend to and are connected to the first arch seat 11 and the third arch seat 13 respectively. At the same time, the first arch seat 11 and the third arch seat 13 are each provided with a row of second tie rods 32 arranged in layers above and below the first tie rods 31. The second pair of tie rods 32 also extend in the longitudinal direction of the bridge, and the tensioning directions of the two rows of tie rods in the same arch seat are opposite.

[0029] Specifically, please combine Figure 2 and Figure 3 One end of the tension rod serves as a tensioning end 33 , and the other end serves as a fixed end 34 .

[0030] In a preferred embodiment, the pair of tie rods of the present application adopts a single-end tensioning method, and the end of the first pair of tie rods 31 close to the second arch seat 12 is the fixed end 34 of the first pair of tie rods 31, and the end of the first pair of tie rods 31 close to the first arch seat 11 or the third arch seat 13 is the tensioning end 33 of the first pair of tie rods 31. The first pair of tie rods 31 located at the first arch seat 11 and the second arch seat 12 are tensioned toward the first arch seat 11, and the first pair of tie rods 31 located between the second arch seat 12 and the third arch seat 13 are tensioned toward the third arch seat 13; the fixed ends 34 of the second pair of tie rods 32 are respectively located at their ends close to the first arch seat 11 or the third arch seat 13, and the second pair of tie rods 32 are both tensioned toward the second arch seat 12.

[0031] Preferably, the tie rods are made of high-quality rolled threaded steel bars, the ends of which are installed on the arch seats connected to them through anchors, and the length of the tensioning end 33 of the tie rod exposed from the anchor is not less than 6 times the pitch of the high-quality rolled threaded steel bars, and the length of the fixed end 34 exposed from the anchor is not less than 1.5 times the outer diameter of the high-quality rolled threaded steel bars.

[0032] As a further preference, the finish-rolled threaded steel in this embodiment adopts PSB830Φ32 finish-rolled threaded steel, and the maximum tensile force that a single piece of the finish-rolled threaded steel can withstand is about 660KN.

[0033] At the same time, a nut 35 is installed at the tensioning end 33 of the tension rod, and the tension rod is locked by tightening the nut 35 .

[0034] Furthermore, the tie rods are detachably connected to the arch seats, and can be installed in tie rod holes within the arch seats. These tie rod holes are formed by pre-buried tubes embedded within each arch seat. These pre-buried tubes extend longitudinally along the bridge, and each arch seat is provided with two rows of pre-buried tubes arranged in layers, one above the other. Furthermore, the two rows of pre-buried tubes are arranged in an opposite direction, resulting in two tie rod holes in the same vertical direction within each arch seat.

[0035] An anchor plate is also provided at the end of each arch seat near the embedded pipe (not shown in the figure, the same below). The anchor plate is made of a precision-rolled threaded steel gasket. The anchor plate is arranged perpendicular to the embedded pipe. When the tension rod is tensioned, it can diffuse the stress generated when the tension rod is tensioned into the arch seat concrete.

[0036] Preferably, the embedded pipe is a PVC pipe, and the inner diameter of the embedded pipe in this application is 5 cm. The layout elevation of the embedded pipe is between +23 and +25 m, and the ground elevation is between +25.5 and +26 m, that is, the tension rod is arranged within a height range of 25.5 to 26 m from the arch seat to the ground of its foundation.

[0037] Furthermore, each row of tie rod holes formed by the embedded pipes is provided with a plurality of holes along the transverse direction of the bridge, and the plurality of tie rod holes include basic holes 41 and reserved holes 42. The reserved holes 42 can be used to add tie rods in the reserved holes 42 for tensioning when the displacement and / or stress of the arch ring and arch foot are too large, so as to make timely adjustments to the tensioning requirements of the arch seat.

[0038] As a preferred embodiment, please combine Figure 4 Each row of tie rod holes is provided with eight holes, of which six are selected as basic holes 41 and the remaining two are reserved holes 42. The two reserved holes 42 are located on either side of the six basic holes 41. The six basic holes 41 can be divided into three groups, each group containing two basic holes 41. The spacing between the two basic holes 41 in each group is 50 cm, and the spacing between two adjacent groups of basic holes 41 is 120 cm. The spacing between the reserved holes 42 and the adjacent basic holes 41 is 120 cm.

[0039] In addition, it should be noted that the position of the tension rod must avoid the arrangement of the arch frame columns of the arch ring support. At the same time, when the tension rod conflicts with the position of the main reinforcement in the arch seat, the position of the main reinforcement in the arch seat needs to be adjusted to avoid damage to the structure of the arch seat during the tensioning process.

[0040] The arch bridge structure of the present application that resists unbalanced horizontal thrust requires that all the tie rods be installed first, and before constructing the arch ring 2 and the arch structure, the tie rods in each arch seat are tensioned accordingly, so that the two adjacent arch seats corresponding to the same span of the arch ring 2 are first subjected to the inward tensioning force of the tie rods, thereby offsetting the unbalanced horizontal tension that the arch seats are subjected to during the construction of the arch ring 2 and the arch structure.

[0041] In order to verify the stress conditions of the arch seats at each construction stage and ensure the structural stress safety, the midas civil finite element software can be used to establish a double-span bridge model and conduct analysis at the construction stage. The maximum unbalanced force for the tensioning and removal of the tie rods is determined by the thrust resistance of each arch seat. The difference in the force value of the tensioning force of the tie rods in adjacent stages shall not be greater than the thrust resistance of each arch seat.

[0042] Specifically, the thrust resistance of each arch seat in this application is 80 tons. The horizontal thrust of the cast arch ring on the arch seats on both sides is about 150 tons. If it is controlled at 160 tons, then before casting the arch ring 2, the tensioning force of the tie rods is pre-tensioned at 80 tons. At this time, the two tie rods in the arch seat 1 corresponding to the arch ring 2 are tensioned at 40 tons, so that the arch seat 1 is subjected to the inward tension of the tie rods, so that it can resist the outward horizontal thrust applied by the arch ring arch foot.

[0043] After the construction of the arch structure (including the arch walls and bridge deck), the total horizontal thrust is controlled at 240 tons. Therefore, the tension rods should be loaded and tensioned by 160 tons to meet the arch seat's thrust resistance requirements. Therefore, six tension rods should be arranged within the arch seat 2, corresponding to the span of the arch ring 4, and pre-tensioned at 40 tons per rod. After the tension rods are tensioned, the construction of the arch structure can proceed to offset the tension of the tension rods on the arch seat.

[0044] In addition, it should be noted that the tie rods are arranged symmetrically from the middle of each row of tie rod holes to both sides. Before the construction of the arch ring 2, the tie rods are arranged in the two basic holes 41 in the middle with a tensioning force of 40 tons per tie rod. After the construction of the arch ring is completed and before the construction of the arch structure, the tie rods arranged in the four basic holes 41 on both sides are tensioned with a force of 40 tons each, so that the total tensioning value of the tie rods reaches 240 tons.

[0045] The tensioning of the tie rods should also adopt a "dual control" approach, focusing on controlling the tensioning force of the tie rods and verifying the elongation of the tie rods. During tensioning, the tensioning method should be used to tension the tie rods to the designed tension force in one go. The error range between the measured elongation and the theoretical elongation after tensioning should be within ±6%. Furthermore, the tensioning speed should be carefully controlled during the tensioning process to prevent accidents such as breakage of the tie rods during tensioning.

[0046] After the construction of the entire bridge is completed, the tie rods can be dismantled to be used in the construction of the next bridge, thereby increasing the utilization rate of the tie rods and reducing costs.

[0047] When removing the tie rods, they should be removed step by step, from both sides of the arch bridge toward the center, span by span. After removal is complete, all tie rods should be removed from both sides of the arch bridge toward the center. Specifically, for a single arch abutment, the unbalanced horizontal thrust during tie rod removal is controlled at 80 tons. Each time the tie rods are removed, two are removed symmetrically, from both sides toward the center, over three steps. After all tie rods have been removed, they can be removed.

[0048] In summary, the arch bridge structure of the present application for resisting unbalanced horizontal thrust is targeted at a double-arch bridge structure. Based on the progress of bridge construction and the unbalanced horizontal thrust caused by the arch ring and arch foot on the arch seat at different construction stages, the tie rods are tensioned step by step before each stage of construction. This effectively offsets the unbalanced horizontal thrust caused to the arch seat at different construction stages, avoids unbalanced deformation of the arch seat during construction, and ensures the structural stability of the arch seat. Before removing the tie rods, the tie rods are unloaded step by step to avoid unbalanced thrust on the arch seat after the tension of the tie rods is instantly unloaded, which helps maintain the structural stability of the arch ring.

[0049] The above description is only part of the implementation methods of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A double-arch bridge structure for resisting unbalanced horizontal thrust, characterized by: The bridge is constructed by cutting out a plurality of tracks from a plurality of trackballs, each of which is adapted to move the trackballs toward the side of the bridge where the bridge is moved in an orderly manner and into a plurality of tracks respectively connected to the bridge frame. The bridge is constructed so that the train of trains can be easily connected to the bridge frame by a plurality of tracks. The bridge is constructed so that the train of trains can be easily connected to the bridge frame by a plurality of tracks. An arch ring and an arch structure are provided between two adjacent arch seats. Before constructing the arch ring and the arch structure, the tension rods in each arch seat are tensioned accordingly, so that the two adjacent arch seats corresponding to the same span of the arch ring are first subjected to the tensioning force of the inward tension rods, and the tension rods include precision-rolled threaded steel bars.

2. The double-arch bridge structure for resisting unbalanced horizontal thrust according to claim 1 is characterized by: The ends of the tie rods are mounted on the abutments via anchors.

3. The double-arch bridge structure for resisting unbalanced horizontal thrust according to claim 2 is characterized by: One end of the tension rod is a tensioning end, and the other end is a fixed end; Among them, the ends of the first pair of tie rods close to the second arch seat are the fixed ends of the first pair of tie rods, and the ends of the first pair of tie rods close to the first arch seat or the third arch seat are the tensioning ends of the first pair of tie rods; the fixed ends of the second pair of tie rods are respectively located at their ends close to the first arch seat or the third arch seat, and the second pair of tie rods are tensioned toward the second arch seat.

4. The double-arch bridge structure for resisting unbalanced horizontal thrust according to claim 3 is characterized by: The length of the tensioning end of the tension rod exposed from the anchor is not less than 6 times the pitch of the finished rolled threaded steel bar, and the length of the fixed end thereof exposed from the anchor is not less than 1.5 times the outer diameter of the finished rolled threaded steel bar.

5. The double-arch bridge structure for resisting unbalanced horizontal thrust according to claim 4 is characterized by: The tensioning end of the tie rod is provided with a nut for locking the tie rod.

6. The double-arch bridge structure for resisting unbalanced horizontal thrust according to claim 4 is characterized by: Anchor plates are installed at both ends of the tie rod.

7. The double-arch bridge structure for resisting unbalanced horizontal thrust according to claim 1 is characterized by: The pre-buried pipe includes a PVC pipe.

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