Construction method of half-through steel pipe concrete arch bridge lattice beam

Abstract

The application provides a construction method of a half-through steel pipe concrete arch bridge lattice beam, which avoids the block of the arch rib and the transverse support structure between the arch ribs to the installation of the lattice beam by optimizing the construction segment division of the lattice beam, so that each construction segment of the lattice beam, especially the arch rib intersection segment, can also be moved to the installation position through horizontal and vertical displacement, thereby avoiding the construction risk caused by the unbalanced stress of the lifting point or the non-stress of the lifting point in the process of large-angle inclination of the arch rib intersection segment to pass through the arch rib. Meanwhile, the lifting capacity of the cable crane is designed, the total number of the construction segments of the lattice beam is reduced after the optimization of the segment division of the lattice beam, the lifting frequency is reduced, and the weight of the construction segment of the lattice beam is close to the weight of the arch rib segment, thereby being beneficial to improving the construction efficiency and reducing the construction cost.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of bridge construction technology, in particular to a construction method of a deck-type steel pipe concrete arch bridge lattice beam. BACKGROUND

[0002] In bridge construction, the deck-type steel pipe concrete arch bridge is widely used due to its unique structure and strong bearing capacity. The construction technology of cable hoisting without support cannot be applied to the hoisting of the deck of the deck-type arch bridge. The reason is that the intersection section of the arch rib of the lattice beam of the deck must pass through the arch rib to be hoisted to the installation position. However, due to the influence of the arch rib and the transverse support between the arch ribs, the intersection section of the arch rib is difficult to pass through the arch rib. Since the width of the lattice beam is usually smaller than the width of the outer edge of the arch rib, it is also difficult to implement the hoisting of the lattice beam outside the arch rib. SUMMARY

[0003] In view of the technical problems mentioned in the background, the present application provides a construction method of a deck-type steel pipe concrete arch bridge lattice beam, which can avoid the blocking of the arch rib and the transverse support between the arch ribs during installation, improve the construction efficiency, and reduce the construction cost.

[0004] To achieve the above-mentioned purpose, the technical solution adopted by the present application is as follows:

[0005] A construction method of a deck-type steel pipe concrete arch bridge lattice beam, the lattice beam of the deck-type steel pipe concrete arch bridge of the prior art comprises a plurality of construction segments, the plurality of construction segments are divided into two construction segment groups symmetrically arranged relative to the center line of the bridge and a closure segment connecting the two construction segment groups, each construction segment group comprises an end segment, an arch rib intersection segment I, an arch rib intersection segment II, an arch rib intersection segment III and N standard segments connected in sequence along the longitudinal direction of the bridge, the end segment is located at the end of the lattice beam, the arch rib intersection segment I, the arch rib intersection segment II and the arch rib intersection segment III are arranged at the intersection of the lattice beam and the arch rib, and each comprises a main intersection segment beam and at least one secondary intersection segment beam connected to the main intersection segment beam, the length of the main intersection segment beam of the arch rib intersection segment III is greater than the arch rib spacing between two arch ribs, and the main intersection segment beam of the arch rib intersection segment III is located below the arch rib, the secondary intersection segment beam of the arch rib intersection segment III is located between the arch ribs, the closure segment connects the standard segments of the two construction segment groups, and the construction method of the deck-type steel pipe concrete arch bridge lattice beam comprises the following steps:

[0006] S1, dividing the construction section of the lattice beam: dividing the intersection sub-beam of the original arch rib intersection section II to the original arch rib intersection section I to form a new arch rib intersection section I; dividing all intersection sub-beams of the original arch rib intersection section III to the intersection main beam of the original arch rib intersection section II to form a new arch rib intersection section II, and dividing the intersection main beam of the original arch rib intersection section III to one of the standard sections to form a reference section, so that each construction section group includes a terminal section, a new arch rib intersection section I, a new arch rib intersection section II, a reference section and N-1 standard sections connected in sequence along the longitudinal bridge direction;

[0007] S2, after the section division of the lattice beam, performing structure collision checking on the installation of the new arch rib intersection section I and the new arch rib intersection section II by drawing or three-dimensional modeling, and entering step S3 after the checking is passed;

[0008] S3, hoisting of the lattice beam construction section: according to the divided construction section, hoisting the divided construction sections in a preset hoisting sequence by using a support-free cable hoisting system.

[0009] Further, the step S3 includes the following steps:

[0010] S31, hoisting the reference section from below the arch rib to a predetermined installation position by using a support-free cable hoisting system, connecting the reference section with four hangers at the installation position of the reference section to form an installation fulcrum after the reference section is in place;

[0011] S32, hoisting the new arch rib intersection section II from above the arch rib to a predetermined installation position by using a support-free cable hoisting system, fixedly connecting one end of the new arch rib intersection section II with one end of the reference section after the new arch rib intersection section II is in place, and supporting and fixing the other end of the new arch rib intersection section II on the lower support of the half-through steel pipe concrete arch bridge;

[0012] S33, hoisting the new arch rib intersection section I from above the arch rib to a predetermined installation position by using a support-free cable hoisting system, fixedly connecting one end of the new arch rib intersection section I with the end of the new arch rib intersection section II away from the reference section after the new arch rib intersection section I is in place, and supporting and fixing the other end of the new arch rib intersection section I on the upper support of the half-through steel pipe concrete arch bridge;

[0013] S33, hoisting the terminal section from above the arch rib to a predetermined installation position by using a support-free cable hoisting system, supporting and fixing one end of the terminal section on the upper support and fixedly connecting the other end of the terminal section with the end of the new arch rib intersection section I away from the arch rib intersection section II after the terminal section is in place, and supporting and fixing the other end of the terminal section on the arch support of the half-through steel pipe concrete arch bridge;

[0014] S33, hoisting one of the standard segments from below the arch rib to a predetermined installation position by using the cable hoisting system without support, connecting the standard segment with the suspender after being in place, and fixing one end of the standard segment to one end of the reference segment away from the intersection II of the arch rib;

[0015] S33, hoisting one of the standard segments from below the arch rib to a predetermined installation position by using the cable hoisting system without support, connecting the standard segment with the suspender after being in place, and fixing one end of the standard segment to one end of the reference segment away from the intersection II of the arch rib;

[0016] S34, hoisting the closure segment from below the arch rib to a predetermined installation position by using the cable hoisting system without support, connecting the closure segment with the suspender after being in place, and fixing the closure segment to the standard segments of the two construction segment groups to complete the closure of the lattice beam.

[0017] Further, the two adjacent construction segments are fixedly connected by using high-strength bolt connection and welding.

[0018] Further, during hoisting, the reference segment, the standard segment and the closure segment are connected with the lifting appliance on the opposite sides, the lifting appliance is provided with an adapter, the adapter is located outside the vertical projection of the arch rib, and the adapter is connected with the lifting rope of the cable hoisting system without support.

[0019] Further, the lifting appliance comprises a main beam and two lifting lugs, one end of the main beam is rotatably connected with the adapter, the two lifting lugs are fixed to the bottom surface of the main beam, the two lifting lugs and the adapter are spaced apart along the length direction of the main beam, and the lifting lugs are detachably connected with the lifting ring of the construction segment to be hoisted.

[0020] Further, the main beam comprises two horizontal plates, two vertical plates and two groups of stiffening plates, the horizontal plates are parallel to the horizontal plane, the two horizontal plates are vertically and parallel spaced apart, the vertical plates are spaced apart along the width direction of the horizontal plates, the vertical plates are perpendicularly and fixedly connected with the two horizontal plates to form a cavity, the two groups of stiffening plates are respectively arranged on the opposite sides of the cavity, a plurality of stiffening plates in each group are spaced apart along the length direction of the horizontal plate, and each stiffening plate is fixedly connected with the two horizontal plates and the vertical plates, the adapter is arranged outside one end of the cavity and rotatably connected with one end of the two horizontal plates, and the lifting lug is fixed to the bottom surface of one of the horizontal plates.

[0021] Further, the lifting lug comprises two lug plates and a bolt, the two lug plates are spaced apart along the length direction of the horizontal plate to form a plug-in space for the lifting ring of the construction segment, and the bolt is detachably inserted through the two lug plates and the lifting ring.

[0022] Further, the standard segment comprises a standard segment main crossbeam and a standard segment secondary crossbeam fixedly connected with the standard segment main crossbeam, and the lifting ring on the standard segment is arranged on the top surface of the standard segment secondary crossbeam to be staggered with the lifting rod embedded pipe position on the standard segment main crossbeam.

[0023] Further, before hoisting by the lifting appliance, the counterforce at each lifting point in the most unfavorable hoisting eccentricity hoisting working condition is calculated by modeling to verify the structural stability of the lifting appliance and the strength of the lifting appliance itself, and construction safety is ensured.

[0024] Due to the above technical scheme, the present application has the following beneficial effects:

[0025] 1. The above half-through steel pipe concrete arch bridge lattice beam construction method optimizes the construction segment division of the lattice beam, avoids the blocking of the arch rib and the transverse support structure between the arch ribs to the installation of the lattice beam, enables each construction segment of the lattice beam, especially the arch rib intersection segment, to be moved to the installation position through horizontal + vertical displacement, thereby eliminating the need to tilt the arch rib intersection segment at a large angle to pass through the arch rib, avoiding the construction risks caused by the unbalanced stress of the lifting point or the non-stress of the lifting point during the hoisting process of the arch rib intersection segment tilted at a large angle. Combined with the design of the hoisting capacity of the cable crane, the optimized lattice beam segment division reduces the total number of construction segments of the lattice beam, reduces the hoisting frequency, and makes the weight of the construction segment of the lattice beam close to the weight of the arch rib segment, thereby facilitating the improvement of construction efficiency and the reduction of construction cost.

[0026] 2. In the above half-through steel pipe concrete arch bridge lattice beam construction method, during the hoisting process of the lattice beam construction segment, the reference segment is first installed, the reference segment is connected with the four lifting rods at the reference segment installation position to form an installation fulcrum, the arch rib intersection segment II, the arch rib intersection segment I and the end segment are sequentially installed from the installation fulcrum in the direction of the arch foot, and the optimization of the construction segment division of the lattice beam enables each construction segment, especially the arch rib intersection segment II, the arch rib intersection segment I and the end segment without lifting rods, to have a fulcrum, thereby eliminating the need to install a support for supporting the construction segment during the hoisting process, and thereby truly realizing the support-free cable hoisting construction, and further improving the construction efficiency.

[0027] 3. In the above half-through steel pipe concrete arch bridge lattice beam construction method, the two adjacent construction segments are fixedly connected in a combination of high-strength bolt connection and welding, reducing the influence of welding deformation on the overall stability of the bridge and ensuring the strength and stability of the joint. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 It is a construction segment division diagram of the prior art half-through steel pipe concrete arch bridge lattice beam.

[0029] Figure 2For Figure 1 An enlarged view of the structure of a construction segment group and a closure segment of the lattice beam shown in Figure 6;

[0030] Figure 3 A structural schematic diagram of a partial lattice beam of a prior art half-through steel pipe concrete arch bridge after installation is completed;

[0031] Figure 4 A schematic diagram of a construction segment division of a lattice beam of a half-through steel pipe concrete arch bridge of a preferred embodiment of the present application;

[0032] Figure 5 A structural schematic diagram of a partial lattice beam after installation is completed of a preferred embodiment of the present application;

[0033] Figures 6 to 9 A schematic diagram of a construction method flow of a lattice beam of a half-through steel pipe concrete arch bridge of a preferred embodiment of the present application;

[0034] Figure 10 A schematic diagram of a connection of a lifting appliance and a construction segment of a preferred embodiment of the present application;

[0035] Figure 11 A structural schematic diagram of a lifting appliance used in a preferred embodiment of the present application;

[0036] Figure 12 For Figure 11 A bottom view;

[0037] Figure 13 A flat lifting model of a reference segment;

[0038] Figure 14 A finite element model of a lifting appliance;

[0039] Figure 15 A lifting point internal force diagram in a lifting process of a reference segment translation;

[0040] Figure 16 A lifting point internal force diagram in a lifting process of a reference segment rotation of 10° around a main cross beam of the reference segment;

[0041] Figure 17 A schematic diagram of a local loading position and force size;

[0042] Figure 18 A stress diagram of a Midas / Fea model (1);

[0043] Figure 19 A stress diagram of a Midas / Fea model (2);

[0044] Figure 20 A displacement diagram of a Midas / Fea model;

[0045] Figure 21The torsional buckling diagram of the whole lifting appliance;

[0046] Figure 22 The torsional buckling diagram of the whole lifting appliance is driven by the cross plate of the bottom of the lifting appliance;

[0047] Main component symbol explanation

[0048] 100, lattice beam; 10, construction segment group; 11, reference segment; 12, end segment; 13, arch rib intersection segment I; 14, arch rib intersection segment II; 15, arch rib intersection segment III; 16, standard segment; 161, standard segment main cross beam; 162, standard segment secondary cross beam; 17, closure segment; 171, closure segment main cross beam; 172, closure segment secondary cross beam; 18, intersection segment main cross beam; 19, intersection segment secondary cross beam; 200, arch rib; 210, cross brace; 21, upper chord tube; 23, lower chord tube; 25, web; 30, upper support; 40, lower support; 50, lifting appliance; 51, adapter; 511, connecting hole; 52, main beam; 521, cross plate; 522, vertical plate; 523, stiffener; 524, cavity; 53, lifting lug; 531, lug plate; 533, bolt; 54, pin shaft; 60, arch support; 70, lifting rod; 80, lifting ring; 90, hoisting rope. DETAILED DESCRIPTION

[0049] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0050] It should be noted that when a component is referred to as being "fixed" to another component, it can be directly on the other component or there can be intervening components. When a component is referred to as being "connected" to another component, it can be directly connected to the other component or there can be intervening components. When a component is referred to as being "disposed" on another component, it can be directly on the other component or there can be intervening components. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0051] Unless otherwise defined, 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 application belongs. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0052] A preferred embodiment of the present application provides a construction method of a half-through steel pipe concrete arch bridge lattice beam. Please also refer to Figure 1 , Figure 2 and Figure 10 The prior art half-through steel pipe concrete arch bridge generally comprises a lattice beam 100 and two arch ribs 200 erected on the lattice beam 100 at opposite sides in the transverse direction of the bridge, each arch rib 200 comprising an upper chord pipe 21, a lower chord pipe 23 and a web 25 connecting the upper chord pipe 21 and the lower chord pipe 23, and the two arch ribs 200 are fixedly connected by a cross strut 210. The lower chord pipe 23 of the arch rib 200 is connected with the lattice beam 100 by a suspender 70.

[0053] The lattice beam 100 of the prior art half-through steel pipe concrete arch bridge comprises a plurality of construction segments (not labeled), which are divided into two construction segment groups 10 symmetrically arranged relative to the bridge midline and a closure segment 17 connecting the two construction segment groups 10. Each construction segment group 10 comprises, in the longitudinal direction of the bridge, an end segment 12, an arch rib intersection segment I 13, an arch rib intersection segment II 14, an arch rib intersection segment III 15 and N standard segments 16, N being an integer greater than 1. The end segment 12 is located at the end of the lattice beam 100, and the arch rib intersection segment I 13, the arch rib intersection segment II 14 and the arch rib intersection segment III 15 are arranged at the intersection of the lattice beam 100 and the arch rib 200. The arch rib intersection segment I 13, the arch rib intersection segment II 14 and the arch rib intersection segment III 15 each comprise an intersection segment main cross beam 18 and at least one intersection segment secondary cross beam 19 fixedly connected with the intersection segment main cross beam 18. Please also refer to Figure 3 The length of the intersection segment main cross beam 18 of the arch rib intersection segment III 15 is greater than the arch rib 200 spacing between the two arch ribs 200, and the intersection segment main cross beam 18 of the arch rib intersection segment III 15 is located below the arch rib 200, and the intersection segment secondary cross beam 19 of the arch rib intersection segment III 15 is located between the arch ribs 200, i.e. between the two arch ribs 200. The closure segment 17 connects the standard segments 16 of the two construction segment groups 10. The construction method of the lattice beam of the prior art half-through steel pipe concrete arch bridge comprises the following steps:

[0054] S100, hoisting of the end segment 12: Since the end segment 12 is located entirely above the arch rib 200, the end segment 12 can be directly hoisted from above the arch rib 200 to the predetermined installation position by using a support-free cable hoisting system. After being positioned, one end of the end segment 12 is fixed to the arch seat 60 of the arch rib 200, and the other end is supported and fixed to the upper support 30 of the upper chord pipe 21 of the arch rib 200. Since there is no suspender 70 connecting the installation position of the end segment 12 with the arch rib 200, the end segment 12 is supported by the upper support 30 of the arch rib 200 and the arch seat 60 of the arch rib 200, thereby providing an installation fulcrum for the connection of subsequent construction segments.

[0055] S200, hoisting of the intersecting section I13 of the arch ribs: The length of the main crossbeam 18 of the intersecting section I13 is greater than the distance between the two arch ribs 200, and the length of the secondary crossbeam 19 of the intersecting section I13 is less than the distance between the two arch ribs 200. (Combined) Figure 3 As can be seen, since the main crossbeam 18 of the intersecting section I13 of the arch ribs is located close to the end section 12, and the main crossbeam 18 of the intersecting section I13 of the arch ribs is located above the arch rib 200, the arch rib intersecting section I13 can be directly hoisted from above the arch rib 200 to the predetermined installation position using a supportless cable hoisting system. After it is in place, one end of the arch rib intersecting section I13 is supported and fixed to the upper support 30 and fixedly connected to the end section 12. Since there is no hanger 70 to connect the arch rib intersecting section I13, the end of the arch rib intersecting section I13 away from the end section 12 in the prior art is a cantilever end, which cannot support the installation of the arch rib intersecting section II14. It is necessary to erect a support below the end of the arch rib intersecting section I13 away from the end section 12 to support the end of the arch rib intersecting section I13 away from the end section 12 and prevent it from being suspended.

[0056] S300, hoisting of the arch rib intersection section II14: The arch rib intersection section II14 is located between the two arch ribs 200. Since the overall width of the arch rib intersection section II14 is smaller than the distance between the two arch ribs 200, the arch rib intersection section II14 can be hoisted directly from above the arch rib 200 to the predetermined installation position using a supportless cable hoisting system. After being in place, one end of the arch rib intersection section II14 is fixedly connected to one end of the far end section 12 of the arch rib intersection section I13, and the other end of the arch rib intersection section II14 is supported and fixed on the lower support 40 of the lower chord tube 23 of the arch rib 200.

[0057] S400, hoisting of the arch rib intersection segment III 15: Since the length of the intersection segment main cross beam 18 of the arch rib intersection segment III 15 is greater than the distance between the arch ribs 200, and the intersection segment main cross beam 18 of the arch rib intersection segment III 15 is located on the side away from the arch rib intersection segment II 14 and below the arch ribs 200, and the intersection segment secondary cross beam 19 of the arch rib intersection segment III 15 is located on the side close to the arch rib intersection segment II 14 and between the arch ribs 200, the arch rib intersection segment III 15 cannot be directly hoisted vertically from below or above the arch ribs 200 to the predetermined installation position, and needs to be hoisted by tilting the arch rib intersection segment III 15 at a large angle to constantly adjust the posture of the arch rib intersection segment III 15 until the arch rib intersection segment III 15 passes through the arch ribs 200 to be hoisted to the installation position. Due to the influence of the arch ribs 200 and the cross braces 210 between the arch ribs 200, the arch rib intersection segment III 15 is difficult to pass through the arch ribs 200, and the hoisting difficulty is relatively large, which reduces the construction efficiency. And the tilting hoisting of the arch rib intersection segment III 15 leads to uneven stress at each hoisting point, which easily causes construction risks.

[0058] S500, one of the standard segments 16 is hoisted from below the arch ribs 200 to the predetermined installation position by using the support-free cable hoisting system, and after being positioned, the standard segment 16 is connected with the suspender 70, and one end of the standard segment 16 is fixedly connected with one end of the arch rib intersection segment III 15 away from the arch rib intersection segment II 14;

[0059] S600, the remaining standard segments 16 of the construction segment group 10 are hoisted from below the arch ribs 200 to the predetermined installation position by using the support-free cable hoisting system, and after being positioned, the standard segments 16 are connected with the suspender 70 at the corresponding positions, and N-1 standard segments 16 are sequentially fixed in the direction away from the corresponding end segment 12;

[0060] S700, the closure segment 17 is hoisted from below the arch ribs 200 to the predetermined installation position by using the support-free cable hoisting system, and after being positioned, the closure segment 17 is connected with the suspender 70 at the corresponding positions, and the closure segment 17 is fixedly connected with the standard segments 16 of the two construction segment groups 10, thereby completing the closure of the lattice beam 100.

[0061] From the above, it can be seen that when the lattice beam segment division method of the prior art is combined with the existing technology of the non-support cable hoisting construction process to carry out the construction of the half-through steel pipe concrete arch bridge lattice beam, when hoisting the arch rib intersection segment I13 at the non-suspender position, a support needs to be erected to support the cantilever end of the arch rib intersection segment I13, and the arch rib intersection segment III15 cannot be directly vertically lifted from below the arch rib 200 or above the arch rib 200 to the preset installation position, and it is necessary to continuously adjust the posture of the arch rib intersection segment III15 by tilting the arch rib intersection segment III15 at a large angle during hoisting until the arch rib intersection segment III15 passes through the arch rib 200 to be hoisted to the installation position, and due to the influence of the arch rib 200 and the cross brace 210 between the arch ribs 200, the arch rib intersection segment III15 is difficult to pass through the arch rib 200, the hoisting difficulty is relatively large, and the construction efficiency is reduced; and the inclined hoisting of the arch rib intersection segment III15 leads to uneven force or no force at the hoisting points, which easily causes construction risks.

[0062] Please see Figure 4 and Figure 5 To solve the above problems, a preferred embodiment of the present application provides a half-through steel pipe concrete arch bridge lattice beam construction method, comprising the following steps:

[0063] S1, optimizing the division of the lattice beam 100 construction segment: dividing the intersection segment secondary cross beam 19 of the original arch rib intersection segment II14 to the original arch rib intersection segment I13 to form a new arch rib intersection segment I13; dividing all the intersection segment secondary cross beams 19 of the original arch rib intersection segment III15 to the intersection segment main cross beam 18 of the original arch rib intersection segment II14 to form a new arch rib intersection segment II14, and dividing the intersection segment main cross beam 18 of the original arch rib intersection segment III15 to one of the standard segments 16 to form a reference segment 11, so that each construction segment group 10 includes an end segment 12, a new arch rib intersection segment I13, a new arch rib intersection segment II14, a reference segment 11 and N-1 standard segments 16 connected in sequence along the longitudinal bridge direction, and compared with the prior art, the arch rib intersection segment III15 is cancelled, the number of construction segments is reduced, and the efficiency of hoisting is improved.

[0064] S2, after the division of the lattice beam 100 segment is completed, the installation of the new arch rib intersection segment I13 and the new arch rib intersection segment II14 is checked for structure collision by using drawing or three-dimensional modeling, and after the check is passed, i.e., no collision occurs, step S3 is entered.

[0065] S3, hoisting of the lattice beam 100 construction segment: according to the divided construction segments, in accordance with the preset hoisting sequence, the non-support cable hoisting system is used to hoist the divided multiple construction segments.

[0066] Please see Figures 6 to 9In the present embodiment, step S3 includes the following steps:

[0067] S31, using the support-free cable hoisting system, hoist the reference segment 11 from below the arch rib 200 to the predetermined installation position, after positioning, connect the reference segment 11 with the four hangers 70 at the installation position of the reference segment 11 to form the installation fulcrum;

[0068] S32, using the support-free cable hoisting system, hoist the new arch rib intersection segment II 14 from above the arch rib 200 to the predetermined installation position, after positioning, fixedly connect one end of the new arch rib intersection segment II 14 with one end of the reference segment 11, and support and fix the other end of the new arch rib intersection segment II 14 on the arch lower support 40 of the half-through steel pipe concrete arch bridge;

[0069] S33, using the support-free cable hoisting system, hoist the new arch rib intersection segment I 13 from above the arch rib 200 to the predetermined installation position, after positioning, fixedly connect one end of the new arch rib intersection segment I 13 with the end of the new arch rib intersection segment II 14 away from the reference segment 11, and support and fix the other end of the new arch rib intersection segment I 13 on the upper support 30 of the half-through steel pipe concrete arch bridge;

[0070] S33, using the support-free cable hoisting system, hoist the end segment 12 from above the arch rib 200 to the predetermined installation position, after positioning, support and fix one end of the end segment 12 on the upper support 30 and fixedly connect it with the end of the new arch rib intersection segment I 13 away from the arch rib intersection segment II 14, and support and fix the other end of the end segment 12 on the arch support 60 of the half-through steel pipe concrete arch bridge;

[0071] S33, using the support-free cable hoisting system, hoist one of the standard segments 16 from below the arch rib 200 to the predetermined installation position, after positioning, connect the standard segment 16 with the hanger 70, and fixedly connect one end of the standard segment 16 with the end of the reference segment 11 away from the arch rib intersection segment II 14;

[0072] S33, using the support-free cable hoisting system, hoist the remaining standard segments 16 of the construction segment group 10 from below the arch rib 200 to the predetermined installation position, after positioning, connect them with the hangers 70 at the corresponding positions, and fixedly connect N-1 standard segments 16 in the direction away from the corresponding reference segment 11 in sequence;

[0073] S34, using the support-free cable hoisting system, hoist the closure segment 17 from below the arch rib 200 to the predetermined installation position, after positioning, connect it with the hanger 70 at the corresponding position, and fixedly connect the closure segment 17 with the standard segments 16 of the two construction segment groups 10 to complete the closure of the lattice beam 100.

[0074] The lattice beam construction method of the half-through steel pipe concrete arch bridge, by optimizing the construction segment division of the lattice beam 100, i.e. dividing the intersection segment main cross beam 18 of the original arch rib intersection segment III 15 to one of the standard segments 16 to form the reference segment 11, dividing all the intersection segment secondary cross beams 19 of the original arch rib intersection segment III 15 to the intersection segment main cross beam 18 of the original arch rib intersection segment II 14 to form the new arch rib intersection segment II 14, thereby enabling the arch rib intersection segment to avoid the blocking of the arch rib and the inter-arch rib cross support structure to the installation of the lattice beam, enabling each construction segment of the lattice beam, especially the arch rib intersection segment, to be moved to the installation position through horizontal + vertical displacement, so that it is not necessary to tilt the arch rib intersection segment at a large angle to pass through the arch rib, avoiding the construction risks caused by the unbalanced force on the lifting point or the lack of force on the lifting point during the large-angle tilting and hoisting of the arch rib intersection segment. At the same time, the lifting capacity of the cable crane is designed, and the optimized segment division of the lattice beam reduces the total number of construction segments of the lattice beam, reduces the hoisting frequency, and thereby improves the construction efficiency and reduces the construction cost.

[0075] The lattice beam construction method of the half-through steel pipe concrete arch bridge, in the hoisting process of the construction segment of the lattice beam, first, the reference segment 11 is installed, the reference segment 11 is connected with the four lifting rods 70 at the installation position of the reference segment to form an installation fulcrum, and then the arch rib intersection segment II 14, the arch rib intersection segment I 13 and the end segment 12 are installed in sequence from the starting point to the direction of the arch foot, and the optimized segment division of the lattice beam 100 enables each construction segment, especially the arch rib intersection segment II 14, the arch rib intersection segment I 13 and the end segment 12 without lifting rods, to have a fulcrum, so that it is not necessary to install a support for supporting the construction segment during hoisting, thereby truly realizing the support-free cable hoisting construction, and further improving the construction efficiency.

[0076] In the prior art, two adjacent construction segments are fixedly connected by welding, resulting in a large number of welding points and deformation of the construction segment due to welding, thereby reducing the stability of the whole bridge. In the present embodiment, to solve this problem, two adjacent construction segments are fixedly connected by a combination of high-strength bolt connection and welding, i.e. part of the connection points are connected by high-strength bolts to reduce the influence of welding deformation on the stability of the whole bridge and ensure the strength and stability of the joint.

[0077] Since the widths of the reference segment 11, the standard segment 16 and the closure segment 17 are all smaller than the distance between the outer edges of the two arch ribs 200, the lifting fittings 50 need to be connected to the opposite sides of the reference segment 11, the standard segment 16 and the closure segment 17 in the transverse direction of the bridge during the hoisting of the reference segment 11, the standard segment 16 and the closure segment 17. Please see Figures 10 to 12The adapter 51 is connected with the lifting rope 90 of the cable hoisting system without support. In the embodiment, the standard segment 16 comprises a standard segment main beam 161 and a standard segment secondary beam 162 fixedly connected with the standard segment main beam 161. The closure segment 17 comprises a closure segment main beam 171 and a closure segment secondary beam 172 fixedly connected with the closure segment main beam 171. The lifting rings of the reference segment 11, the standard segment 16 and the closure segment 17 connected with the hoist 50 are all arranged on the secondary beams of the corresponding construction segments, so as to be staggered with the positions of the lifting rod embedded pipes (not shown in the figure) on the corresponding main beams.

[0078] In the embodiment, the adapter 51 connected with the lifting rope 90 is located outside the vertical projection of the arch rib 200, so that the lifting rope 90 is located outside the arch rib 200, and the horizontal bracing 210 between the two arch ribs 200 does not affect the horizontal movement of the reference segment 11, the standard segment 16 and the closure segment 17. For the end segment 12, the new arch rib intersection segment I 13 and the new arch rib intersection segment II 14, there is no horizontal bracing 210 between the arch ribs 200 at the installation positions, so the lifting rope 90 can be directly connected with the lifting rings on the end segment 12, the new arch rib intersection segment I 13 and the new arch rib intersection segment II 14 for hoisting.

[0079] In the embodiment, the hoist 50 comprises a main beam 52 and two lifting lugs 53. One end of the main beam 52 is rotatably connected with the adapter 51. The two lifting lugs 53 are fixedly arranged on the bottom surface of the main beam 52. The two lifting lugs 53 and the adapter 51 are arranged along the length direction of the main beam 52. The lifting lug 53 is detachably connected with the construction segment to be hoisted.

[0080] Specifically, the main beam 52 comprises two horizontal plates 521, two vertical plates 522 and two groups of stiffening plates 523. The horizontal plates 521 are parallel to the horizontal plane and are arranged in parallel and spaced apart along the vertical direction. The vertical plates 522 are arranged in parallel and spaced apart along the width direction of the horizontal plates 521. The vertical plates 522 are fixedly connected with the two horizontal plates 521 to form a cavity 524. The two groups of stiffening plates 523 are arranged on opposite sides of the cavity 524. The stiffening plates 523 in each group are arranged in parallel and spaced apart along the length direction of the horizontal plates 521. Each stiffening plate 523 is fixedly connected with the two horizontal plates 521 and the vertical plate 522. The double-web box-shaped hoist formed by the two horizontal plates 521, the two vertical plates 522 and the two groups of stiffening plates 523 can improve the torsional resistance of the hoist 50, so as to meet the rigidity requirement of the construction.

[0081] The adapter 51 is arranged outside one end of the cavity 524 and rotatably connects one end of the two horizontal plates 521. In the embodiment, one end of the adapter 51 is rotatably connected to one end of the two horizontal plates 521 through a pin shaft 54, and the other end of the adapter 51 is provided with a connecting hole 511 for connecting with the hoisting rope, specifically, the hoisting rope 90 can be connected with the connecting hole 511 through a shackle (not shown). The lifting lug 53 is fixed to the bottom surface of one of the horizontal plates 521. In the embodiment, the lifting lug 53 includes two lug plates 531 and a plug pin 533, the two lug plates 531 are arranged opposite and spaced apart along the length direction of the horizontal plate 521 to form a plug-in space (not labeled) for inserting the lifting ring on the construction segment; the plug pin 533 is detachably inserted through the lifting ring 80 between the two lug plates 531 and the two lug plates 531, so as to connect the construction segment to be hoisted and the lifting device 50 together.

[0082] The effect of the lattice beam construction method of the half-through steel pipe concrete arch bridge of the present application is described below with a specific embodiment.

[0083] A certain super-large bridge has a total length of 514 meters, and the main bridge is a single-span half-through steel pipe concrete arch bridge with a bridge length of 356 meters (calculated span of 340 meters, vector-span ratio of 1:4.00, and arch axis coefficient m=1.5), which spans the Hongshui River. According to the characteristics of the project, the upper steel structure of the main bridge is constructed by using the non-support cable hoisting construction technology, and the design of the non-support cable hoisting system is described as follows.

[0084] The maximum allowable hoisting weight of the designed hoisting system is 160 tons, and the system is a single-main-span double-cable structure-2*80t cable, and the maximum hoisting weight of a single cable is 80 tons, and the two groups of cables can work independently. Four groups of working cables are arranged on the whole bridge, the designed hoisting weight is 5 tons, and the main span of the cable system is 545.0 meters, the small pile number tail span is 229.5 meters, and the large pile number tail span is 234 meters.

[0085] The design parameters of the upper steel structure of the main bridge of the certain half-through steel pipe concrete arch bridge are shown in the following Table 1 and Table 2:

[0086] Table 1 Weight statistics table of main arch rib segments

[0087]

[0088]

[0089] Table 2 Weight statistics table of each construction segment of the lattice beam in the prior art

[0090]

[0091] According to the above parameter statistics table, the maximum lifting weight of the arch rib segment is 145.6 tons, and the maximum construction segment of the lattice beam is 121.7 tons, with a weight difference of 23.9 tons, accounting for 16.41% and 19.64% of the maximum arch rib and the maximum lattice beam weight, respectively. Therefore, the original design of the steel structure theoretical weight still has optimization space.

[0092] In the lattice beam construction method of the half-through steel pipe concrete arch bridge of the embodiment, three key factors of the arch column, the position of the lattice beam support on the bridge, and the installation and positioning of the lattice beam, and other factors are comprehensively considered, a new lattice beam construction segment division method is proposed, and the optimization of the lattice beam construction segment division is carried out by step S1. The optimized lattice beam hoisting segment weight statistics table is shown in Table 3.

[0093] Table 3 Optimized lattice beam hoisting segment weight statistics table

[0094]

[0095]

[0096] After the optimization of the lattice beam construction segment, the maximum lifting weight of the arch rib segment is 145.6 tons, and the maximum construction segment of the lattice beam is 151.5 tons, with a weight difference of 5.9 tons, accounting for 4.05% and 3.89%, respectively. Therefore, the optimized segment theoretical weight is more reasonable, which is conducive to reducing the construction cost.

[0097] In addition, in the present example, the connection lifting point of the reference segment 11 and the lifting appliance 50 and the connection lifting point of the standard segment 16 and the lifting appliance 50 are arranged on the secondary cross beam of the corresponding segment. At this time, it can be determined that a certain eccentric force will be generated during hoisting. Therefore, before hoisting the standard segment by using the lifting appliance, the reaction force at each lifting point under the most unfavorable hoisting weight (i.e. the maximum hoisting weight) eccentric lifting condition needs to be calculated to verify the structural stability of the lifting appliance and the strength of the lifting appliance itself, so as to ensure the construction safety. The verification method is as follows:

[0098] The lifting appliance 50 of the embodiment is made of Q355C. During hoisting, the adapter 51 of the lifting appliance 50 and the main beam 52 are connected by the pin shaft 54, and the lifting lug 53 and the construction segment are connected by the pin 533. The pin shaft 54 and the pin 533 can rotate, so the main beam 52 will reach a self-balancing state with the rotation of the pin shaft 54 and the pin 533. The main beam 52 is basically in a translational lifting state, so only the following two working conditions in Table 4 are considered:

[0099] Table 4 Calculation working conditions of each construction segment

[0100]

[0101] The lifting appliance 50 is applied to the construction segment of the arch under the segmental beam, that is, the lifting of the reference segment 11, the standard segment 16 and the closure segment 17, so only the working condition of the reference segment 11 (the heaviest segment) is calculated, the Midas / Civil software is used for modeling analysis, the model is shown in Figure 13 , and the internal force of the reference segment 11 under each working condition is shown in Table 5.

[0102] Table 5 Internal force statistics table of segment

[0103]

[0104] The entity analysis is carried out by Midas / Fea, the mesh is divided into tetrahedron, and the minimum mesh size of the tetrahedron is 10mm. The steel plate material is Q355C, the load simulation is simulated by extracting the internal force of the Midas / Civil lifting point to the node coupling mode to be applied on the lifting ring, wherein the number of structure division units is 1472192, the number of nodes is 327517, and the finite element model of the lifting appliance 50 is shown in Figure 14 .

[0105] (1) Local stress calculation of the first lifting segment of the lattice beam

[0106] The Midas / Civil is used to establish the lattice reference segment model, the translation lifting process and the rotation of 10° around the heavier main cross beam are simulated, and the maximum internal force of the lifting point position is extracted, as shown in Figure 15 , Figure 16 .

[0107] As shown in Figure 15 , Figure 16 , in the translation lifting process of the reference segment 11, the maximum reaction force of the lifting point position is F Z = 365.5kN, which includes the weight of one lifting appliance; in the lifting process of the reference segment 11 rotating 10° around the reference segment main cross beam 18, the maximum reaction force of the lifting point position is F Z = 353.7kN, from the stress analysis, the internal force of each lifting point under the analysis working condition of rotating 10° around the reference segment main cross beam 18 is relatively average, and the pin 533 and the pin shaft 54 can rotate, so the analysis working condition can be more consistent with the actual lifting situation in the field. Considering the safety, the support reaction is 40t, the support reaction is applied to the Midas / Fea model by node coupling, and the loading schematic is shown in Figure 17 , wherein the calculation result is shown in Figures 18 to 19 .

[0108] As shown in Figure 18 , the lifting appliance of the lattice beam simulates the lifting process of the lattice beam under the action of 40t tension force, ignoring some stress concentration points, the maximum von mises stress of the lifting lug 53 is 284.2Mpa, and the maximum stress position is shown in Figure 19As shown, the maximum stress is located at the connection between the lifting lug 53 and the horizontal plate 521 of the lifting device 50; as can be seen from the figure, the area with stress exceeding 213.2 MPa is less than 0.5%, and the area with greater stress is concentrated in the bending area of ​​the two horizontal plates 521 of the lifting device 50.

[0109] Depend on Figure 20 It can be seen that under the action of a 40t pulling force, the vertical displacement of the lifting device 50 is 10.7mm. The total length of the lifting device 50 is 4580mm. The vertical displacement value is less than L / 400mm, which meets the requirements.

[0110] In summary, through analysis of the two lifting processes of the reference section lifting equipment, a maximum support reaction force of 40t was taken for verification to ensure safety. The finite element calculation results show that the stress is at the local location and the area accounts for a small proportion. The error of the finite element numerical simulation cannot be ruled out. By improving the welding quality at this location on site, the overall stress and displacement of the structure can meet the requirements. Therefore, the force of the 40t lifting equipment meets the specifications.

[0111] (2) Buckling mode analysis of lifting equipment

[0112] Under a vertical load of 60t, the buckling modes of the lifting device 50 were analyzed, resulting in five analytical modes. The overall analysis results are shown in Table 6.

[0113] Table 6. Buckling Analysis of Lifting Gear

[0114]

[0115] Modes 1 and 2 belong to the buckling analysis of the beam, and the structure is as follows: Figures 21-22 As shown.

[0116] As shown in the figure, the lifting device will buckle and become unstable when it bends by more than 12cm. The actual displacement of the lifting device 50 is 1cm, which is much less than the buckling limit of 12cm. Therefore, the double-web box-type lifting device has good torsional performance and can meet the rigidity requirements of construction.

[0117] The above description is a detailed description of the preferred embodiments of the present invention. However, the embodiments are not intended to limit the scope of the patent application of the present invention. All equivalent changes or modifications made under the technical spirit of the present invention should fall within the patent scope covered by the present invention.

Claims

1. A method for constructing a lattice beam of a half-through steel pipe concrete arch bridge, wherein the lattice beam of the half-through steel pipe concrete arch bridge in the prior art comprises a plurality of construction segments, the plurality of construction segments are divided into two construction segment groups symmetrically arranged relative to a bridge midline and a closure segment connecting the two construction segment groups, each construction segment group comprises, in sequence along a longitudinal direction of the bridge, an end segment, an arch rib intersection segment I, an arch rib intersection segment II, an arch rib intersection segment III and N standard segments, the end segment is located at an end of the lattice beam, the arch rib intersection segment I, the arch rib intersection segment II and the arch rib intersection segment III are all arranged at intersections of the lattice beam and arch ribs, and each comprises a main intersection segment beam and at least one secondary intersection segment beam connected to the main intersection segment beam, the main intersection segment beam of the arch rib intersection segment III has a length greater than an arch rib spacing between two arch ribs, and is located below the arch ribs, the secondary intersection segment beam of the arch rib intersection segment III is located between the arch ribs, and the closure segment connects the standard segments of the two construction segment groups, characterized in that, The lattice beam construction method of the half-through steel pipe concrete arch bridge comprises the following steps: S1, optimizing the division of the lattice beam construction section: the intersection segment secondary cross beam of the original arch rib intersection segment II is divided to the original arch rib intersection segment I to form a new arch rib intersection segment I; all intersection segment secondary cross beams of the original arch rib intersection segment III are divided to the intersection segment primary cross beam of the original arch rib intersection segment II to form a new arch rib intersection segment II, and the intersection segment primary cross beam of the original arch rib intersection segment III is divided to one of the standard segments to form a reference segment, so that each construction section group comprises a terminal segment, a new arch rib intersection segment I, a new arch rib intersection segment II, a reference segment and N-1 standard segments which are sequentially connected along the longitudinal bridge direction; S2, after the division of the lattice beam section is completed, the installation of the new arch rib intersection segment I and the new arch rib intersection segment II is subjected to structure collision checking by means of drawing or three-dimensional modeling, and after the checking is passed, step S3 is entered; S3, hoisting of the lattice beam construction section: according to the divided construction section, the divided multiple construction sections are hoisted by using a support-free cable hoisting system in a preset hoisting sequence, and the step S3 comprises the following steps: S31, the reference segment is hoisted from below the arch rib to a predetermined installation position by using the support-free cable hoisting system, the reference segment is connected with four hangers at the installation position of the reference segment after being positioned, and an installation fulcrum is formed; S32, the new arch rib intersection segment II is hoisted from above the arch rib to a predetermined installation position by using the support-free cable hoisting system, one end of the new arch rib intersection segment II is fixedly connected with one end of the reference segment after being positioned, and the other end of the new arch rib intersection segment II is supported and fixed on the lower support of the half-through steel pipe concrete arch bridge; S33, the new arch rib intersection segment I is hoisted from above the arch rib to a predetermined installation position by using the support-free cable hoisting system, one end of the new arch rib intersection segment I is fixedly connected with the end of the new arch rib intersection segment II which is away from the reference segment after being positioned, and the other end of the new arch rib intersection segment I is supported and fixed on the upper support of the half-through steel pipe concrete arch bridge; S33, the terminal segment is hoisted from above the arch rib to a predetermined installation position by using the support-free cable hoisting system, one end of the terminal segment is supported and fixed on the upper support and fixedly connected with the end of the new arch rib intersection segment I which is away from the arch rib intersection segment II after being positioned, and the other end of the terminal segment is supported and fixed on the arch support of the half-through steel pipe concrete arch bridge; S33, one of the standard segments is hoisted from below the arch rib to a predetermined installation position by using the support-free cable hoisting system, the standard segment is connected with a hanger after being positioned, and one end of the standard segment is fixedly connected with the end of the reference segment which is away from the arch rib intersection segment II; S33, the remaining standard segments of the construction section group are hoisted from below the arch rib to predetermined installation positions by using the support-free cable hoisting system, the standard segments are connected with hangers at corresponding positions after being positioned, and N-1 standard segments are sequentially fixed in a direction away from the corresponding reference segment. S34, hoisting the closure segment from below the arch rib to a predetermined installation position by using a support-free cable hoisting system, connecting the closure segment with the suspender at the corresponding position, and fixing and connecting the standard segment of the two construction segment groups to complete the closure of the lattice beam.

2. The method of claim 1, wherein the method further comprises: The two adjacent construction segments are fixed and connected by using a combination of high-strength bolt connection and welding.

3. The method of claim 1, wherein the method further comprises: During hoisting, the lifting fittings are connected to the opposite sides of the reference segment, the standard segment and the closure segment, the adapter is arranged on the lifting fitting, the adapter is located outside the vertical projection of the arch rib, and the adapter is connected with the lifting rope of the support-free cable hoisting system.

4. The method of claim 3, wherein the lattice beam of the half-through steel tube concrete arch bridge is constructed by the steps of: The lifting fitting comprises a main beam and two lifting lugs, one end of the main beam is rotationally connected with the adapter, the two lifting lugs are fixed to the bottom surface of the main beam, the two lifting lugs and the adapter are arranged in the length direction of the main beam, and the lifting lug is detachably connected with the lifting ring of the construction segment to be hoisted.

5. The construction method for the grid beam of a mid-span steel-concrete composite arch bridge as described in claim 4, characterized in that, The main beam comprises two horizontal plates, two vertical plates and two groups of stiffening plates, the horizontal plates are parallel to the horizontal plane, and the two horizontal plates are arranged in parallel and spaced apart in the vertical direction, the two vertical plates are arranged in spaced apart in the width direction of the horizontal plate, the vertical plate is fixedly connected with the two horizontal plates to form a cavity, and the two groups of stiffening plates are arranged on the opposite sides of the cavity, a plurality of stiffening plates in each group are arranged in spaced apart in the length direction of the horizontal plate, and each stiffening plate is fixedly connected with the two horizontal plates and the vertical plate, the adapter is arranged outside one end of the cavity and rotationally connected with one end of the two horizontal plates, and the lifting lug is fixed to the bottom surface of one of the horizontal plates.

6. The construction method for the grid beam of a mid-span steel-concrete composite arch bridge as described in claim 5, characterized in that, The lifting lug comprises two lug plates and a bolt, the two lug plates are arranged in spaced apart in the length direction of the horizontal plate to form a plug-in space for the lifting ring on the construction segment, and the bolt is detachably inserted through the two lug plates and the lifting ring.

7. The construction method for the grid beams of a mid-span steel-concrete composite arch bridge as described in claim 4, characterized in that, The standard segment comprises a standard segment main cross beam and a standard segment secondary cross beam fixedly connected with the standard segment main cross beam, and the lifting ring on the standard segment is arranged on the top surface of the standard segment secondary cross beam to be staggered with the position of the suspender embedded pipe on the standard segment main cross beam.

8. The construction method for the grid beam of a mid-span steel-concrete composite arch bridge as described in claim 7, characterized in that, Before hoisting by using the lifting fitting, the reaction force at each lifting point under the most unfavorable hoisting eccentricity hoisting condition is calculated by modeling to verify the structural stability of the lifting fitting and the strength of the lifting fitting itself, and the construction safety is ensured.

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