CN113062231A

CN113062231A - Cantilever pouring arch ring construction device and construction method

Info

Publication number: CN113062231A
Application number: CN202110368273.1A
Authority: CN
Inventors: 杨洋; 王毅力; 黄康; 徐荣鹏; 吴娇媚; 陶小兰; 王鹏
Original assignee: China Merchants Chongqing Communications Research and Design Institute Co Ltd
Current assignee: China Merchants Chongqing Communications Research and Design Institute Co Ltd
Priority date: 2021-04-06
Filing date: 2021-04-06
Publication date: 2021-07-02
Anticipated expiration: 2041-04-06
Also published as: CN113062231B

Abstract

The invention discloses a cantilever casting arch ring construction device which comprises a falsework, a buckle cable, an anchorage, a back cable and a horizontal cable. The falsework is arranged on one side of an arch springing of the arch ring, one end of the buckle cable is connected with the segment, and the other end of the buckle cable is connected with the falsework. The anchor is arranged on one side of the falsework, which is far away from the arch ring, and the back cable is connected with the anchor and the falsework. The horizontal cable is tensioned between the two opposite sections and is used for offsetting construction bending moment applied by the buckling cable. The invention also provides a construction method for pouring the arch ring by the cantilever. According to the cantilever pouring arch ring construction device and the construction method, the horizontal cable can offset the construction bending moment applied by the buckling cable, the arch ring is not influenced by the horizontal component of the tension of the buckling cable, the calculation of the construction process is simplified, the internal force of the arch ring is more controllable, the machining and the installation of a steel structure hinge at the arch springing position are omitted, and the maximum span of the cantilever construction main arch ring is further increased.

Description

Cantilever pouring arch ring construction device and construction method

Technical Field

The invention relates to the technical field of bridge construction, in particular to a cantilever pouring arch ring construction device and a construction method.

Background

With the rapid development of the construction technology of the buckle cable and the hanging basket, at present, a part of reinforced concrete overpass arch bridges with the span of 100m to 250m are in China, and a construction method of cantilever pouring is adopted. As shown in FIG. 1, in the process of pouring the cantilever, a large arch ring structure needs a falsework guy cable structure as a temporary support measure to prevent the arch ring structure from being damaged or collapsed under the action of self weight. As shown in fig. 2, since the buckle cable has a certain inclined pulling angle, the buckle cable supports the weight of the arch ring and simultaneously applies a large horizontal pulling force to the arch ring, so that the arch ring generates a large construction bending moment.

The other one of the two conventional solutions is that in the construction process of an arch ring, part of a previously tensioned buckling rope is loosened, so that the arch foot position bears more load, opposite bending moment is generated on part of arch sections, and excessive additional bending moment is offset. And the other is to arrange a hinge support at the arch springing position to release the bending moment at the position.

However, the above two solutions have the following problems: (1) a strict calculation method for optimizing the internal force of the arch ring is not provided, and complicated manual trial calculation is needed to determine the cable releasing position and the construction stage; (2) the hinge support is arranged at the arch springing, a huge steel structure hinge needs to be processed, the cost is high, and only the bending moment at the arch springing can be released; (3) the extra construction internal force generated by the guy cable, the actual internal force of the arch ring and the designed bridge forming internal force are greatly different, and the previously calculated arch shaft coefficient is influenced and is not in an optimized state. (4) The extra construction load produced by the buckling rope influences the arch ring line shape. (5) Due to the existence of construction bending moment, the span of the main arch is difficult to exceed 350m under the construction method.

Disclosure of Invention

Therefore, it is necessary to provide a cantilever casting arch ring construction device and a construction method aiming at the problem that the arch ring generates a large construction bending moment due to the fact that the buckling cable exerts a large horizontal pulling force on the arch ring while supporting the weight of the arch ring.

A cast-in-cantilever arch ring construction apparatus in which an arch ring includes a plurality of segments which are closed from arch foot positions at both ends of the arch ring to form the arch ring, comprising:

the falsework is arranged on one side of an arch springing of the arch ring;

one end of the buckling rope is connected with the segment, and the other end of the buckling rope is connected with the falsework;

the anchorage is arranged on one side of the falsework, which is far away from the arch ring;

the back cable is used for connecting the anchorage and the falsework; and

and the horizontal cable is tensioned between the two opposite sections and is used for offsetting construction bending moment applied by the buckling cable.

In one of the embodiments, the lower edge of the segments is provided with an anchoring toothed plate on which the horizontal cables are anchored by means of an anchoring system.

In one embodiment, the anchoring system comprises a pre-stressed anchoring device and a pre-buried pipe, the pre-stressed anchoring device is mounted on the anchoring toothed plate, the pre-buried pipe is connected with the anchoring toothed plate, and the end part of the horizontal cable passes through the pre-buried pipe and then is anchored by the pre-stressed anchoring device.

In one embodiment, the embedded pipe comprises a straight pipe section close to the prestressed anchoring device and a bent pipe section far away from the prestressed anchoring device, the bent pipe section is connected with the straight pipe section, and the straight pipe section and the bent pipe section form an included angle.

In one embodiment, the anchoring system further comprises a shock-absorbing block and a waterproof jacket, the shock-absorbing block and the waterproof jacket are sleeved on the horizontal cable, and the shock-absorbing block is located between the embedded pipe and the waterproof jacket.

In one embodiment, the system further comprises a cable traction system and a bracket bearing system, wherein the bracket bearing system is provided with a plurality of brackets, and a dragger of the cable traction system drags the horizontal cable to pass through the brackets on the bracket bearing system in sequence.

A construction method for pouring an arch ring by a cantilever comprises the following steps:

two segments opposite to the arch ring are poured, then a buckle cable and a back cable are tensioned, the buckle cable is connected with the segments and the falsework, and the back cable is connected with the falsework and the anchorage;

tensioning a horizontal cable, and respectively connecting two ends of the horizontal cable with the two opposite segments so as to offset the construction bending moment applied by the buckling cable;

and sequentially pouring two opposite sections of the arch ring, tensioning the corresponding buckling cables and the back cables, and then tensioning the corresponding horizontal cables until the arch ring is closed.

In one embodiment, the arrangement of the two opposite segments of the casting arch ring further comprises:

and constructing foundations, anchorages and falsework of the arch bridge.

In one embodiment, when constructing the segments at the arch springing positions of the arch rings, firstly, a support is erected, the segments are constructed and poured on the support, buckling cables are installed for the segments, corresponding back cables are installed, and then the support is detached.

In one embodiment, the step of tensioning the horizontal cable and connecting two ends of the horizontal cable to two opposite segments respectively is specifically as follows:

dragging the horizontal cable by a dragger on a cable traction system to enable the horizontal cable to sequentially pass through brackets on a bearing system, then enabling the end part of the horizontal cable to pass through a pre-buried pipe, and anchoring the end part of the horizontal cable by a pre-stressed anchoring device after the end part of the horizontal cable passes through the pre-buried pipe.

According to the cantilever casting arch ring construction device and the construction method, the horizontal cable can offset the construction bending moment applied by the buckling cable, the arch ring is not influenced by the horizontal component of the tension of the buckling cable, the calculation of the construction process is simplified, the internal force of the arch ring is more controllable, and the machining and the installation of steel structure hinges at the arch foot are omitted. When the arch rings are closed, the internal force and the line shape of the arch rings are almost the same as those of the full-hall support construction condition, the internal force during construction is eliminated, the actual internal force of the arch rings is the same as the designed bridge forming internal force, the arch shaft coefficient design is effective, the line shape of the arch rings is easier to control, and the maximum span of the cantilever construction main arch ring is further increased.

Drawings

In order to more clearly illustrate the embodiments of the present invention, the drawings, which are required to be used in the embodiments, will be briefly described below. In all the drawings, the elements or parts are not necessarily drawn to actual scale.

FIG. 1 is a schematic view of a falsework lanyard structure temporary support arch ring segment;

FIG. 2 is a schematic view of a construction bending moment generated by an arch ring when a horizontal pulling force is applied to the arch ring by a buckle cable;

FIG. 3 is a schematic view of a cantilever placing arch ring construction apparatus according to an embodiment;

FIG. 4 is a schematic illustration of the tension of a horizontal cable counteracting the tension of a lanyard;

FIG. 5 is a schematic view of a closed triangle formed by the tension of the lanyard, the tension of the horizontal cable, and the segment gravity;

FIG. 6 is a schematic view of an anchoring tooth plate connecting horizontal cables in one embodiment;

FIG. 7 is a schematic view of an anchoring system anchoring horizontal cables in one embodiment;

FIG. 8 is a flow chart of a cantilever placing arch ring construction method according to an embodiment;

FIG. 9 is a schematic view of a segment at the arch springing of the pouring construction arch;

FIG. 10 is a schematic view of a horizontal cable connecting two opposing segments at the arch springing of the arch ring;

FIG. 11 is a schematic view of casting a next segment over a segment;

FIG. 12 is a schematic view of the tensioning of the corresponding lanyard, backstay and horizontal cords of the next section;

FIG. 13 is a schematic view of sequential casting of segments and tensioning of the ripcords, backstays, and horizontal cables;

figure 14 is a schematic view of a cable pulling system and a cradle loadbearing system construction horizontal cable.

Reference numerals:

10-arch ring, 12-segment, 20-falsework, 30-buckle cable, 40-anchorage, 50-back cable, 60-horizontal cable, 70-anchoring toothed plate, 80-anchoring system, 82-prestressed anchoring device, 84-embedded pipe, 842-straight pipe section, 844-bent pipe section, 86-damping block, 88-waterproof sleeve, 90-bracket, 92-cable traction system, 922-pulling device, 94-bracket bearing system and 942-bracket.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein, but rather should be construed as broadly as the present invention is capable of modification in various respects, all without departing from the spirit and scope of the present invention.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only and do not represent the only embodiments.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

Referring to fig. 3, in an embodiment of the apparatus for constructing a cast-in-place arch ring, the internal force and the line shape of the arch ring 10 can be optimized. The arch ring 10 comprises a plurality of segments 12, and the segments 12 are closed to each other from arch foot positions at two ends of the arch ring 10 to form the arch ring 10. Specifically, the cantilever casting arch ring construction device comprises a falsework 20, a buckle cable 30, an anchorage 40, a back cable 50 and a horizontal cable 60.

Falsework 20 is arranged at one side of arch springing 10, the falsework 20 is vertically arranged, and the positions of the arch springing at the two ends of the arch springing 10 are respectively provided with one falsework 20 correspondingly. One end of each buckle cable 30 is connected with the corresponding segment 12, the other end of each buckle cable 30 is connected with the corresponding falsework 20, each segment 12 is correspondingly connected with one buckle cable 30, and the buckle cables 30 can temporarily support the segments 12 and prevent the arch ring 10 from being damaged or collapsed under the action of self weight.

The anchors 40 are arranged on one side of the falsework 20 far away from the arch ring 10, namely the falsework 20 is arranged between the arch ring 10 and the anchors 40, and the back cables 50 connect the anchors 40 and the falsework 20. The back cables 50 may balance the tension of the buckle cables 30 on the scaffold 20, keeping the scaffold 20 balanced. One back cable 50 may be provided for each buckle cable 30, and of course, one back cable 50 may be provided for each buckle cable 30.

Referring to fig. 4 and 5, the horizontal cable 60 is stretched between two opposite segments 12, the two opposite segments 12 are symmetrical about the center line of the arch 10, the two opposite segments 12 have the same height, and the horizontal cable 60 is stretched to be approximately horizontal. The tension force provided by the horizontal cable 60 is exactly equal to the horizontal component of the tension force of the stay buckle cable 30, i.e. the resultant force of the buckle cable 30 and the horizontal cable 60 is a vertical force, and the horizontal cable 60 can offset the construction bending moment applied by the buckle cable 30.

For example, the weight of the segment 12 and the form is W, the tension of the lanyard 30 should be calculated as P ═ W/sin α, and the tension of the horizontal lanyard 60 should be calculated as N ═ W/tan α, where α is the angle between the lanyard and the horizontal. If the horizontal cable 60 and the buckle cable 30 are both tensioned, and the weight of the arch section is W, the three forces just form a closed triangle, and the arch ring 10 is not additionally stressed.

Referring to fig. 6 and 7, in one embodiment, the lower edge of the segment 12 is provided with an anchor plate 70, and the horizontal cable 60 is anchored to the anchor plate 70 by an anchor system 80. Specifically, the anchoring system 80 includes a pre-stressed anchoring device 82 and an embedded pipe 84, the pre-stressed anchoring device 82 is installed on the anchoring toothed plate 70, the embedded pipe 84 is connected with the anchoring toothed plate 70, and the end of the horizontal cable 60 is anchored by the pre-stressed anchoring device 82 after passing through the embedded pipe 84. The embedded pipe 84 can protect the horizontal cable 60 and avoid the horizontal cable 60 from being damaged by friction with the segment 12. In one embodiment, the horizontal cable 60 may be a steel strand, and the pre-stressed anchoring device 82 may fix the end of the horizontal cable 60 by split anchoring.

On the basis of the above embodiment, further, the embedded tube 84 includes a straight tube 842 and a bent tube 844, the straight tube 842 is close to the prestressed anchoring device 82, and the straight tube 842 is installed on the anchoring toothed plate 70. The bent pipe section 844 is far away from the prestressed anchoring device 82, the bent pipe section 844 is connected with the straight pipe section 842, the straight pipe section 842 is obliquely arranged, the bent pipe section 844 is connected with the straight pipe section 842 and then bends and horizontally extends, and the bent pipe section 844 and the straight pipe section 842 form an included angle, so that the inclined horizontal cable 60 is gradually bent to be in an approximately horizontal state.

In one embodiment, the anchoring system 80 further comprises a shock block 86 and a waterproof jacket 88, wherein the shock block 86 and the waterproof jacket 88 are both sleeved on the horizontal cable 60, and the shock block 86 is located between the embedded pipe 84 and the waterproof jacket 88. The waterproof jacket 88 can prevent external moisture from entering the embedded pipe 84, and further corrode the end of the horizontal cable 60. The shock absorption block 86 can prevent the horizontal cable 60 from vibrating and ensure the anchoring stability of the horizontal cable 60.

Referring to fig. 8, the present invention also provides a method for constructing a cast-in-place arch ring, which uses the apparatus for constructing a cast-in-place arch ring. Specifically, the construction method comprises the following steps:

step S110: two opposite segments 12 of the arch ring 10 are poured, then the guy wires 30 and the back wires 50 are tensioned, the guy wires 30 are connected with the segments 12 and the falsework 20, and the back wires 50 are connected with the falsework 20 and the anchorage 40.

Referring to fig. 9 and 10, specifically, in the process of pouring the segments 12 of the arch ring 10, the segments 12 at the corresponding positions at the two ends of the arch ring 10 need to be poured, so that the segments 12 are poured in pairs. The two segments 12 in the pair may be cast simultaneously, and certainly, the two segments 12 in the pair may be cast successively. The two segments 12 in the pair are poured and the guy 30 and the backstay 50 are stretched after the concrete reaches the designed strength.

When the buckle cable 30 is stretched, one end of the buckle cable 30 is connected with the segment 12, and the other end of the buckle cable 30 is obliquely connected with the falsework 20, so that the buckle cable 30 temporarily supports the segment 12. The back cables 50 are then tensioned, the back cables 50 connecting the anchors 40 and the falsework 20 to maintain the falsework 20 balanced. When constructing the segments 12 at the arch springing position of the arch ring 10, i.e. the first segments 12 at the two ends of the arch ring 10, the bracket 90 needs to be erected first, then the segments 12 are poured on the bracket 90, the buckle cables 30 are installed for the segments 12, and the bracket 90 can be removed after tensioning the corresponding back cables 50.

In one embodiment, before the step S110, the method further includes: and constructing a foundation of the arch ring 10, an anchorage 40 and the falsework 20. Before the segments 12 of the arch ring 10 are poured, early preparation work needs to be carried out, namely, a foundation of the arch ring 10 is constructed, then a falsework 20 is constructed at the arch springing position of the arch ring 10, an anchorage 40 is constructed on one side of the falsework 20 far away from the arch ring 10, and the anchorage 40 is spaced from the falsework 20 by a certain distance.

Step S120: and tensioning the horizontal cable 60, and connecting two ends of the horizontal cable 60 with the two opposite segments 12 respectively to offset the construction bending moment applied by the buckle cable 30.

Specifically, the two opposite segments 12 are poured, after the corresponding lanyards 30 and the back cables 50 are stretched, the corresponding horizontal cables 60 are stretched, and the two ends of the horizontal cables 60 are respectively connected with the two segments 12. The tension force provided by the horizontal cable 60 is exactly equal to the horizontal component of the tension force of the stay buckle cable 30, i.e. the resultant force of the buckle cable 30 and the horizontal cable 60 is a vertical force, and the horizontal cable 60 can offset the construction bending moment applied by the buckle cable 30.

In one embodiment, the step of attaching the horizontal cable 60 to the segment 12 is embodied as: after the waterproof jacket 88 and the shock absorption block 86 are sequentially sleeved on the horizontal cable 60, the horizontal cable 60 passes through the embedded pipe 84, the pre-stressed anchoring device 82 is installed on the anchor toothed plate 70, and then the end of the horizontal cable 60 is anchored and fixed by the pre-stressed anchoring device 82. The waterproof jacket 88 can prevent external moisture from entering the embedded pipe 84, the shock absorption block 86 can prevent the horizontal cable 60 from vibrating, and the bent pipe section 844 of the embedded pipe 84 can enable the horizontal cable 60 to be in an approximately horizontal state.

Step S130: the two opposite segments 12 of the arch ring 10 are poured in sequence, the corresponding buckle cables 30 and the back cables 50 are tensioned, and then the corresponding horizontal cables 60 are tensioned until the arch ring 10 is closed.

Referring to fig. 11 to 13, specifically, the above steps are repeated, and each subsequent segment 12 is repeatedly constructed, and after the buckle cable 30 and the back cable 50 are tensioned each time, the corresponding horizontal cable 60 is tensioned, so as to eliminate the additional construction bending moment caused by the buckle cable 30, until the arch ring 10 is closed, thereby forming the integral structure. And finally, all the buckle cables 30, the back cables 50 and the horizontal cables 60 are dismantled, and the construction of the whole cast-in-place arch ring 10 is completed.

In one embodiment, during actual implementation, the sag effect of the horizontal cable 60 due to its own weight is calculated, and the angle of the embedded pipe 84 is corrected by the following formula:

wherein k is_BThe slope of an included angle between the embedded pipe 84 and a horizontal line, rho is the dead weight of the stay cable unit length, L is the horizontal projection length of the stay cable, and N is the tension horizontal force.

Referring to fig. 14, in one embodiment, in the case of a long horizontal cable 60, a set of cable traction systems 92 and a set of brackets 942 load bearing systems 94 are provided. During construction, the horizontal cable 60 is pulled by the puller 922 on the cable traction system 92 to pass through the bracket 942 on the bearing system in sequence until the opposite bank, and the horizontal cable 60 passes through the embedded pipe 84, and the end of the horizontal cable 60 is fixed by the prestressed anchoring device 82.

According to the cantilever casting arch ring construction device and the construction method, the horizontal cable 60 can offset the construction bending moment applied by the buckle cable 30, the arch ring 10 cannot be influenced by the horizontal component of the tension of the buckle cable 30, the calculation of the construction process is simplified, and the internal force of the arch ring 10 is more controllable. The processing and the installation of the steel structure hinge at the arch springing are omitted. When the arch ring 10 is closed, the internal force and the line shape of the arch ring 10 are almost the same as those of the full support 90 under the construction condition, the construction internal force is eliminated, the actual internal force of the arch ring 10 is the same as the designed bridge forming internal force, the arch shaft coefficient design is effective, the line shape of the arch ring 10 is easier to control, and the maximum span of the cantilever construction main arch ring 10 is further increased.

The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention, and they should be construed as being included in the following claims and description.

Claims

1. A kind of cast-in-cantilever arch ring construction equipment, wherein the arch ring includes a plurality of sections, the said section closes the dragon and forms the said arch ring from the arch springing position of the said arch ring both ends each other, characterized by that, this cast-in-cantilever arch ring construction equipment includes:

the falsework is arranged on one side of an arch springing of the arch ring;

the back cable is used for connecting the anchorage and the falsework; and

2. The cast-in-cantilever arch ring construction device of claim 1, wherein the lower edge of the segment is provided with an anchoring toothed plate on which the horizontal cable is anchored by an anchoring system.

3. The apparatus of claim 2, wherein the anchoring system comprises a pre-stressed anchoring device and a pre-buried pipe, the pre-stressed anchoring device is mounted on the anchor toothed plate, the pre-buried pipe is connected with the anchor toothed plate, and the end of the horizontal cable is anchored by the pre-stressed anchoring device after passing through the pre-buried pipe.

4. The device of claim 3, wherein the pre-buried pipe comprises a straight pipe section close to the pre-stressed anchoring device and a bent pipe section far from the pre-stressed anchoring device, the bent pipe section is connected with the straight pipe section, and the straight pipe section and the bent pipe section form an included angle.

5. The cast-in-cantilever arch ring construction device of claim 4, wherein the anchoring system further comprises a shock-absorbing block and a waterproof jacket, the shock-absorbing block and the waterproof jacket are sleeved on the horizontal cable, and the shock-absorbing block is located between the embedded pipe and the waterproof jacket.

6. The cast-in-cantilever arch ring construction device of claim 1, further comprising a cable pulling system and a carriage bearing system, the carriage bearing system having a plurality of carriages, the horizontal cable being pulled by the puller of the cable pulling system sequentially through the carriages on the carriage bearing system.

7. The construction method for pouring the arch ring by the cantilever is characterized by comprising the following steps of:

8. The cast-in-place-in-cantilever arch construction method of claim 7, wherein the arrangement of the opposed two segments of the cast-in-place arch is preceded by:

and constructing foundations, anchorages and falsework of the arch bridge.

9. The cast-in-place-in-cantilever arch ring construction method according to claim 7, wherein when constructing the segment at the arch foot position of the arch ring, a bracket is firstly erected, a casting segment is constructed on the bracket, a buckle cable is installed for the segment, a corresponding back cable is installed, and then the bracket is dismantled.

10. The cast-in-place-in-cantilever arch ring construction method according to claim 7, wherein the step of tensioning the horizontal cable and connecting the two ends of the horizontal cable to the two opposite segments respectively comprises: