A through-type suspension bridge machine and a construction method thereof

Abstract

This invention provides a bottom-bearing cantilever bridge construction machine and its construction method, including a saddle beam, side beams, an outer formwork system, an inner formwork system, a bottom formwork system, and a construction support mechanism. The construction support mechanism includes a bottom crossbeam, a support rod, a support tie rod, and a rod rotation assembly. The bottom crossbeam is arranged laterally and located below the bottom slab of the already poured concrete beam. A top support cylinder is installed on the top of the bottom crossbeam and supported on the bottom slab of the already poured concrete beam. The support rod is hinged to the bottom of the rear end of the side beam and the end of the bottom crossbeam. The support tie rod is hinged to the end of the bottom crossbeam and the side beam. The rod rotation assembly adjusts the angle between the support rod and the bottom crossbeam. During the pouring construction, the side beams are supported by the construction support mechanism in the solid area of ​​the bottom slab of the concrete beam, balancing the overturning force. It is not limited by the size and weight of the poured box girder segment, making it suitable for pouring larger box girder segments and ensuring the entire machine remains in a safe and stable state.

Description

Technical Field

[0001] This invention relates to the field of bridge-building machine technology, and in particular to a bottom-bearing cantilever bridge-building machine and its construction method. Background Technology

[0002] With the booming development of China's construction industry, bridge engineering in China has also made great strides. Large-span variable cross-section continuous beams, with their advantages of good integrity, high stiffness, high safety, large single-span capacity, and fewer expansion joints, are widely used in bridge construction. The main construction methods include cast-in-place construction with scaffolding and cantilever construction. The cantilever construction method, due to its advantages such as being unaffected by terrain, not encroaching on the clearance under the bridge, and being able to carry out construction without interrupting traffic under the bridge, is widely used in large and medium-span prestressed concrete continuous beam bridges, especially for bridges crossing valleys, existing roads, and waterways. The cantilever construction method is a very important box girder construction mode, which involves dividing the beam into several sections and constructing them symmetrically using a cantilevered formwork.

[0003] Currently, there are two types of hanging basket equipment on the market. One type has the main load-bearing component installed above the bridge deck, occupying a large amount of bridge deck construction space. During construction, the segmental reinforcement needs to be tied to the formwork on-site before subsequent work can proceed, resulting in high risks and low construction efficiency. The other type has the main load-bearing component installed below the bridge deck, but the load-bearing part in the poured state relies on the flange plate of the box girder. However, the flange plate of the box girder is not a good choice for heavy load bearing. It has strict limitations on the weight of the poured segment. Once it exceeds the load-bearing range of the concrete beam flange plate, it is easy to cause concrete cracking and beam damage, resulting in high safety risks. This is especially true for highway beams, whose flange plates are relatively thin and have even greater load-bearing limitations. Summary of the Invention

[0004] To address the aforementioned shortcomings in the existing technology, this invention provides a bottom-bearing cantilever bridge-building machine and its construction method. During the pouring construction, the side beams are supported by a construction support mechanism on the solid area of ​​the bottom plate of the concrete beam, balancing the overturning force. It is not limited by the size and weight of the poured box girder segment, and can be applied to the pouring construction of larger box girder segments. This can improve the efficiency of bridge construction and keep the whole machine in a safe and stable state at all times.

[0005] The technical solution adopted to achieve the above-mentioned objectives of this invention is as follows:

[0006] A bottom-bearing cantilever bridge construction machine includes at least a saddle beam, side beams, an outer formwork system, an inner formwork system, and a bottom formwork system. A construction support mechanism is installed at the rear of the side beams. The construction support mechanism includes:

[0007] The bottom crossbeam is arranged transversely and located below the bottom plate of the cast-in-place concrete beam. A top support cylinder is installed on the top of the bottom crossbeam. During the casting and through-hole inversion of the force system, the top support cylinder is supported on the bottom plate of the cast-in-place concrete beam.

[0008] The support rods are provided in two parts. The top ends of the two support rods are hinged to the bottom of the rear end of the side beam, and the bottom ends of the two support rods are respectively connected to the two ends of the bottom crossbeam.

[0009] The support diagonal brace consists of two rods, the bottom ends of which are hinged to the two ends of the bottom crossbeam, and the top ends of which are hinged to the side beam; the support diagonal brace is an adjustable telescopic rod.

[0010] The boom rotation assembly includes two hydraulic cylinders, which are inclinedly hinged between the supporting booms and the side beams on both sides. The hydraulic cylinders extend and retract to adjust the angle between the supporting booms and the bottom crossbeam.

[0011] The top of the rear end of the side beam is hinged to an overpass support wheel assembly. The overpass support wheel assembly can be flipped so that it supports or detaches from the flange plate of the cast concrete beam. The locking pin locks and fixes the overpass support wheel assembly.

[0012] The support rod is provided with pin holes. The bottom end of the support rod is connected to the sleeve at the end of the bottom crossbeam. The support rod moves up and down along the sleeve. The alignment pin is connected to the pin holes of the support rod and the bottom crossbeam, thereby adjusting the length of the support rod.

[0013] The under-deck cantilever bridge construction machine is equipped with a steel cage transporter, which is located above the bridge deck.

[0014] The saddle beam includes a main beam arranged in the transverse direction and two hanging beams connected to the bottom of both ends of the main beam. The two hanging beams form a C-shaped structure with the main beam. The main beam is connected to the bridge deck of the cast-in-place concrete beam and can slide longitudinally along the bridge deck. The hanging beams extend to the underside of the flange plate of the cast-in-place concrete beam and are connected to the side beams.

[0015] The bottom of the saddle beam is also equipped with a support cylinder, which plays a supporting role during the casting and the inversion of the force system through the hole.

[0016] Two side beams are arranged longitudinally. The two side beams are respectively connected to the bottom of the saddle beam and located below the flange plate of the cast-in-place concrete beam. The two side beams extend to the front of the cast-in-place concrete beam, and the front ends of the two side beams are connected to the front suspension beam arranged transversely.

[0017] During the pouring process, an upper anchor bolt assembly connects the side beams and the saddle beams.

[0018] The wing mold of the outer mold system is erected on the side beam; the inner mold system is fixed with a support beam arranged longitudinally, the front end of the support beam is supported on the front hanging beam, and the rear end of the support beam is suspended on the top plate of the poured concrete beam; the front cross beam of the bottom mold system is suspended on the front hanging beam, and the rear cross beam of the bottom mold system is suspended on the side beam and the bottom plate of the poured concrete beam.

[0019] This invention also provides a construction method for a bottom-bearing cantilever bridge construction machine, comprising the following steps:

[0020] Step 1: After the pouring of segment #1 is completed and the concrete beam segment reaches the required strength, install longitudinal sliding rails and longitudinal hydraulic cylinders at both ends of the poured concrete beam.

[0021] Step 2: The two bridge-building machines descend and demold;

[0022] Step 3: Install the span support wheel group on the side beam so that the rear of the side beam is supported on the already poured concrete beam; disconnect the connection between the two bridge building machines and move the two bridge building machines forward longitudinally across the span. At this time, the outer formwork system and the bottom formwork system cross the span together with the saddle beam and the side beam, and the inner formwork system is suspended on the newly poured concrete beam.

[0023] Step 4: After the longitudinal movement across the span is completed, install and adjust the construction support mechanism, with the span support wheel assembly suspended in the air;

[0024] Step 5: Raise the bridge-building machine to the height of the outer formwork system and install the outer formwork system and bottom formwork system in place to meet the construction requirements of segment #2; adjust the construction support mechanism so that it is supported on the bottom plate of the already poured concrete beam;

[0025] Step 6: Hoist the steel cage to segment #2 and place it in the formwork, then connect the steel cage to the reserved steel bars of the previous segment;

[0026] Step 7: Insert the inner formwork system into the steel cage and adjust the inner formwork system to the construction state of segment #2;

[0027] Step 8: Begin pouring the concrete for the current segment #2.

[0028] Compared with the prior art, the technical solution provided by the present invention has the following advantages: (1) When the under-bearing suspended bridge construction machine provided by the present invention passes through the span, the middle part of the side beam is suspended under the concrete beam by the saddle beam, and the rear part of the side beam is supported by the over-span support wheel group under the flange plate of the concrete beam, so that it will not tilt forward. The construction support mechanism and the external formwork system attached thereto move over the span together with it. During the pouring construction, the side beam is fixed to the poured concrete beam by the upper anchor rod assembly through the saddle beam, and the inner and outer formwork systems are fixed to the front part of the side beam. The rear part of the side beam is pressed against the bottom of the concrete beam by the construction support mechanism to provide rear anchor force and prevent it from tilting forward.

[0029] (2) Under the pouring state, the under-bearing suspended bridge building machine provided by the present invention has a heavy load. The force system is changed from the overturning moment balanced by the cross-span support wheel group when passing through the hole to the support of the rear anchor assembly and construction support mechanism. The construction support mechanism bears the load at the bottom of the concrete beam, balancing the overturning moment of the front lifting beam, formwork and the poured segment beam, avoiding damage to the box girder flange plate under heavy load, and is safe and reliable. The bridge building machine is not limited by the size and weight of the poured segment box girder, and can be used for the pouring construction of larger segment box girders, which can improve the efficiency of bridge construction, and the whole machine is always in a safe and stable state.

[0030] (3) The side beam of the under-bearing cantilever bridge building machine provided by the present invention is located at the lower part of the flange of the concrete beam. The only supporting component on the bridge deck is the saddle beam, which occupies very little bridge deck space and leaves a bridge deck working space to complete a variety of construction operations. The bridge building machine is equipped with a steel cage transporter, which facilitates the overall installation of the precast steel cage. Moreover, the bridge building machine can move across the span by itself and has the ability to perform curved construction.

[0031] (4) When the under-bearing suspended bridge construction machine provided by the present invention carries the template through the hole, the overall load is relatively light. The overturning moment of the front suspension beam and the template can be balanced by only using the over-span support wheel group. Therefore, the hole crossing is efficient and safe.

[0032] (5) The construction support mechanism in this invention has a simple structure and is easy to adjust, and can always ensure that the construction support mechanism is vertically supported on the bottom plate of the concrete beam. Attached Figure Description

[0033] Figure 1 This invention provides an installation side view of the under-bearing cantilever bridge construction machine;

[0034] Figure 2 for Figure 1 Schematic diagram of section AA;

[0035] Figure 3 for Figure 1 Schematic diagram of the BB section;

[0036] Figure 4 for Figure 1 Schematic diagram of the C-section;

[0037] Figure 5 This is a schematic diagram of the saddle beam in this invention. In the figure, (a) is the front view of the saddle beam, (b) is the top view of the saddle beam, and (c) is the side view of the saddle beam.

[0038] Figure 6The following is a schematic diagram of the side beam structure in this invention. In the figure, (a) is a side view of the side beam, (b) is a top view of the side beam, (c) is a structural diagram of the side inclined support truss, (d) is a schematic diagram of section AA in (a), (e) is a schematic diagram of section BB in (a), and (f) is a schematic diagram of section CC in (a).

[0039] Figure 7 This is a schematic diagram of the front suspension beam in the present invention. In the figure, (a) is a structural diagram of the front facade truss, (b) is a structural diagram of the front planar truss, (c) is a structural diagram of the front inclined support truss, and (d) is a side view of the front suspension beam.

[0040] Figure 8 This is a schematic diagram of the structure of the external mold system in this invention. In the figure, (a) is a side view of the external mold system and (b) is a front view of the external mold system.

[0041] Figure 9 This is a schematic diagram of the internal mold system in this invention. In the figure, (a) is the front view of the internal mold system and (b) is the side view of the external mold system.

[0042] Figure 10 This is a schematic diagram of the bottom mold system in this invention. In the figure, (a) is the front view of the bottom mold system, (b) is the top view of the bottom mold system, and (c) is the side view of the bottom mold system.

[0043] Figure 11 This is a schematic diagram of the overpass support wheel assembly in the present invention. In the figure, (a) is a side view of the overpass support wheel assembly and (b) is a front view of the overpass support wheel assembly.

[0044] Figure 12 This is a schematic diagram of the installation of the over-span support wheel assembly in this invention. In the figure, (a) is a side view of the over-span support wheel assembly supported on the cast-in-place concrete beam, (b) is a front view of the over-span support wheel assembly supported on the cast-in-place concrete beam, and (c) is a front view of the over-span support wheel assembly detached from the cast-in-place concrete beam.

[0045] Figure 13 This is a schematic diagram of the construction support mechanism in this invention. In the figure, (a) is the front view of the construction support mechanism and (b) is the view of the construction support mechanism.

[0046] Figure 14 This is a schematic diagram of the installation of the construction support mechanism in this invention. In the figure, (a) is a side view of the construction support mechanism installation and (b) is a front view of the construction support mechanism installation.

[0047] Figure 15 This is a schematic diagram of the arrangement of the steel cage transporter in this invention;

[0048] Figure 16This is a schematic diagram of the rebar cage transporter in this invention. In the figure, (a) is a side view of the rebar cage transporter and (b) is a front view of the rebar cage transporter.

[0049] In the diagram: 100-Poured concrete beam; 1-Saddle beam, 101-Main beam, 102-Hanging beam, 103-Sliding seat, 104-Longitudinal slide rail, 105-Longitudinal movement cylinder, 106-Support cylinder; 2-Side beam, 201-Side elevation truss, 202-Side plane truss, 203-Side inclined support truss, 204-Ear plate, 205-Mounting seat, 206-Hinged seat; 3-Front hanging beam, 301-Front elevation truss, 302-Front plane truss, 303-Front inclined support truss; 4-Outer formwork system, 401-Wing formwork, 402-Outer formwork; 5-Inner formwork system, 501-Top formwork, 502-Side formwork, 503-Top support frame, 504-Side support frame, 505-Opening cylinder, 506-Support beam; 6-Bottom formwork system. 601-Support frame; 602-Bottom formwork panel; 701-Inner formwork rear anchor bolt assembly; 702-Bottom formwork front anchor bolt assembly; 703-Bottom formwork rear outer anchor bolt assembly; 704-Bottom formwork rear inner anchor bolt assembly; 705-Upper anchor bolt assembly; 8-Overspan support wheel assembly; 801-Wheel seat; 802-Wheel assembly frame; 803-Wheel assembly; 9-Construction support mechanism; 901-Bottom crossbeam; 902-Top support cylinder; 903-Supporting rod; 904-Supporting diagonal tie rod; 905-Rod rotation assembly; 906-Electric chain hoist; 907-Hanging frame; 10-Working platform; 11-Rebar cage transporter; 1101-Tower; 1102-Main transport beam; 1103-Lifting trolley; 1104-Traveling mechanism; 1105-Transporting anchor bolt. Detailed Implementation

[0050] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0051] The overall structure of the under-bearing cantilever bridge-building machine provided in this embodiment is as follows: Figures 1-4 As shown, it includes a saddle beam 1, side beams 2, front lifting beam 3, outer formwork system 4, inner formwork system 5, bottom formwork system 6, span support wheel group 8, construction support mechanism 9, working platform 10, and hydraulic and electrical system.

[0052] The structure of a saddle beam is as follows: Figure 5As shown, the structure includes a main beam 101 arranged transversely and two hanging beams 102 connected to the bottom of both ends of the main beam. The two hanging beams form a C-shape with the main beam. The main beam is connected to the bridge deck of the pre-cast concrete beam 100 and can slide longitudinally along the bridge deck. The hanging beams extend below the flange plates of the pre-cast concrete beam and connect to the side beams. Specifically, a sliding block 103 is installed at the bottom of the main beam. The sliding block is mounted on a longitudinal slide rail 104 set on the bridge deck. A longitudinal movement cylinder 105 connects the sliding block and the longitudinal slide rail. Under the action of the longitudinal movement cylinder, the saddle beam slides longitudinally along the bridge deck, thereby pushing the entire bridge-building machine forward across the span. Furthermore, hinged sliding blocks are connected to the bottom ends of both outer sides of the main beam, and two longitudinal slide rails and two longitudinal movement cylinders are correspondingly provided. In this embodiment, a support cylinder 106 is also installed at the bottom of the saddle beam. During the casting and the inversion of the force system when passing through the hole, the support cylinder plays a supporting role, that is, supporting the saddle beam. When passing through the hole, the support cylinder is retracted, and the bridge building machine is supported by the slide block onto the longitudinal slide rail of the bridge deck. Under the action of the longitudinal movement cylinder, it is pushed forward to cross the span.

[0053] Two side beams are provided longitudinally, and the two side beams are respectively connected to the bottom of both ends of the saddle beam and located below the flange plate of the cast-in-place concrete beam, see... Figure 2 Furthermore, the two side beams extend to the front of the already poured concrete beam, meaning the saddle beam connects to the middle of the side beams. Specifically, the side beams have a right-angled triangular cross-section, such as... Figure 6 As shown, the side beam includes a connected side elevation truss 201, a side plane truss 202, and a side inclined support truss 203, wherein the side elevation truss is the main load-bearing truss; the side plane truss is a horizontal stiffening truss and can also be used as a working platform; and the side inclined support truss is a stabilizing truss. Specifically, the front end of the side beam is provided with an ear plate 204 for connecting the front suspension beam, and a mounting seat 205 for connecting the overspan support wheel assembly is correspondingly provided on the side beam. A hinge seat 206 for connecting the support rod, the rod rotation assembly, and the support tie rod of the construction support mechanism is correspondingly provided on the side beam.

[0054] The front suspension beam is positioned laterally and connects to the front ends of the two side beams. The cross-section of the front suspension beam is also a right-angled triangular structure, as shown below. Figure 7 As shown, the system includes a front facade truss 301, a front planar truss 302, and a front inclined support truss 303 connected to each other. The front facade truss is the main load-bearing truss; the front planar truss is a horizontal stiffening truss and can also be used as a working platform; the front inclined support truss is a stabilizing truss. In this embodiment, the inclined sides of the side beams and the front suspension beam (side inclined support truss and front inclined support truss) are both set outwards. The front suspension beam mainly bears the vertical force of the four bottom formwork front anchor bolt assemblies at the front of the bottom formwork system and the front end support reaction force of the inner formwork, and then transfers it to the side beams.

[0055] The outer mold system includes the connected wing mold 401 and outer mold 402, such as Figure 8As shown, in this embodiment, the wing mold of the outer mold system is mounted on the side beam. Figure 2 Specifically, the wing formwork of the outer formwork system is slidably connected to the side plane truss of the side beam and moves laterally along the side beam to open the formwork. Furthermore, the wing formwork is connected to a transverse slide rail on the side beam by a sliding pair, and can be pushed and pulled by a hydraulic cylinder to achieve a transverse opening of approximately 100mm, ensuring that the outer formwork does not rub against the concrete beam when moving forward across the span. During pouring, the outer formwork system and the inner formwork system are connected by tie rods to prevent formwork bulging.

[0056] The internal mold system includes a top mold plate 501, side mold plates 502, a top support frame 503, a side support frame 504, and a mold opening cylinder 505, such as Figure 9 As shown, the top formwork is fixed to the top support frame, and the side formwork is fixed to the side support frame. The side support frame and the top support frame are hinged together, and opening cylinders are distributed and connected between the side support frame and the top support frame. The opening cylinders push and pull to achieve rotational demolding. A longitudinally arranged support beam 506 is installed on the top support frame of the inner mold system. During pouring, the front end of the support beam is supported on the front plane truss of the front suspension beam, and the rear end of the support beam is suspended on the top slab of the already poured concrete beam. When passing through a hole, the front end of the support beam is disconnected from the front suspension beam, the middle of the support beam is suspended on the top slab of the front end of the freshly poured concrete beam, and the rear end of the support beam remains stationary. Specifically, two support beams are distributed and installed on the top support frame. During pouring, the rear ends of the two support beams are suspended on the top slab of the already poured concrete beam through the inner mold rear anchor rod assembly 701. Figure 3 Furthermore, the upper part of the inner formwork rear anchor assembly is anchored to the top slab of the already poured concrete beam, and the lower end of the inner formwork rear anchor assembly is suspended in the duct of the support beam. The support beam can be moved longitudinally along the duct to adjust its position. Two sets of inner formwork rear anchor assemblies are correspondingly provided. Specifically, when passing through the duct, the support beam changes from being supported at the front end to being suspended from the middle on the top slab at the front end of the newly poured concrete beam. The support beam moves longitudinally backward along the duct into the interior of the newly poured concrete beam, leaving space for the overall hoisting of the reinforcing cage. After the reinforcing cage is put into the formwork, it moves longitudinally forward along the duct to the front suspension beam and connects with it.

[0057] The bottom formwork system is an all-steel structure, such as Figure 10 As shown, the system includes a support frame 601 and a bottom formwork panel 602 fixed to the support frame. The support frame is a frame structure composed of a front crossbeam, a rear crossbeam, and several sets of longitudinal support beams. The front crossbeam of the bottom formwork system is suspended from the front suspension beam, and the rear crossbeam of the bottom formwork system is suspended from the side beams and the bottom plate of the already poured concrete beams. Specifically, the suspension point of the rear crossbeam on the side beam is located directly below the saddle beam, meaning that the entire outer formwork system, inner formwork system, and bottom formwork system are all located in front of the saddle beam.

[0058] Specifically, the front crossbeam of the bottom formwork system is suspended from the front lifting beam by four sets of bottom formwork front anchor bolt assemblies 702, see... Figure 2Furthermore, the upper part of the front anchor bolt assembly of the bottom formwork is anchored to the front suspension beam, and the lower end of the front anchor bolt assembly is suspended from the front crossbeam. Specifically, the rear crossbeam of the bottom formwork system is suspended from the bottom plates of the side beams and the already poured concrete beams by the rear outer anchor bolt assembly 703 and the rear inner anchor bolt assembly 704, respectively. Figure 3 Furthermore, two sets of rear external anchor bolt assemblies are provided for the bottom formwork, with their upper parts anchored to the side beams and located directly below the saddle beams. The lower ends of the rear external anchor bolt assemblies are suspended from both ends of the rear cross beams. Two sets of rear internal anchor bolt assemblies are provided for the bottom formwork, with their upper parts anchored to the bottom plate of the already poured concrete beam cavity. The lower ends of the rear internal anchor bolt assemblies are suspended from the rear cross beams.

[0059] To ensure the stability of the support, during the pouring process, upper anchor rod assemblies 705 are connected between the side beams and the saddle beam. Two sets of upper anchor rod assemblies are connected between each side beam and the saddle beam, that is, four sets of upper anchor rod assemblies are set accordingly. The upper part of the four sets of upper anchor rod assemblies is anchored to the saddle beam, and the lower end of the four sets of upper anchor rod assemblies passes through the flange plate of the poured concrete beam and is suspended on the side beam.

[0060] In this embodiment, the overpass support wheel assembly is hinged to the top of the rear end of the side beam, allowing the overpass support wheel assembly to be flipped. Figure 12 As shown, when passing through the hole, the overspan support wheel assembly flips over and supports itself below the flange plate of the already poured concrete beam, providing downward support reaction force to the rear end of the side beam and preventing the side beam from overturning forward when passing through the hole. During the pouring construction, the overspan support wheel assembly needs to be flipped over to detach from the already poured concrete beam to prevent it from continuing to support the concrete beam and becoming an unnecessary constraint. Specifically, one set of overspan support wheel assemblies is installed at the rear end of each of the two side beams, that is, two sets of overspan support wheel assemblies are correspondingly provided. Further, after the overspan support wheel assembly flips over and supports itself on the already poured concrete beam when passing through the hole, it needs to be locked and fixed by locking pins. The overspan support wheel assembly includes a wheel seat 801, a wheel frame 802, and a wheel assembly 803, as shown below. Figure 11 As shown, the wheel seat is hinged to the top of the rear end of the side beam and can be flipped laterally. The wheel assembly frame is fixed on the wheel seat, and the wheel assembly is installed on the wheel seat. When the over-span support wheel assembly is supported below the flange of the cast-in-place concrete beam, the wheel assembly contacts the flange of the cast-in-place concrete beam.

[0061] The construction support mechanism is the main load-bearing component during bridge-building machine casting, including the bottom crossbeam 901, support rods 903, support tie rods 904, and rod rotation assembly 905, such as... Figure 13As shown. The bottom crossbeam is arranged transversely and located below the cast-in-place concrete beam base slab. A top support cylinder 902 is installed on the top of the bottom crossbeam. Two support rods are provided, with their top ends hinged to the bottom of the rear end of the side beam, and their bottom ends connected to both ends of the bottom crossbeam. Specifically, the support rods are provided with pin holes. The top end of the support rod is hinged to a hinge seat below the tail of the side beam, and the bottom end of the support rod is connected to a sleeve at the end of the bottom crossbeam. The support rod and the bottom crossbeam are connected by an alignment pin, and the support rod acts as a tie rod during operation. The support rod can move up and down along the sleeve on the bottom crossbeam, and the alignment pin is connected to the pin hole of the support rod and the bottom crossbeam, thereby adjusting the length of the support rod.

[0062] Two supporting diagonal braces are provided. The bottom ends of the two supporting diagonal braces are respectively hinged to the two ends of the bottom crossbeam, and the top ends of the two supporting diagonal braces are hinged to the side beam, such as... Figure 14 As shown. The supporting diagonal tie rod is an adjustable telescopic rod. After the length is adjusted to the correct position, the telescopic sleeves are locked together with hydraulic pins. The supporting diagonal tie rod is a stabilizing rod, ensuring that the bottom crossbeam always acts vertically (along the transverse direction) onto the concrete beam base plate during operation and that the force is stable and does not slip. In this embodiment, the hanger rotation assembly includes two hydraulic cylinders. The two hydraulic cylinders are inclinedly hinged between the upper part of the supporting hanger rod and the side beam on both sides. The hydraulic cylinders extend and retract, adjusting the angle between the supporting hanger rod and the bottom crossbeam, so that the working position of the supporting hanger rod is precisely adjusted to ensure that when the top support cylinder on the bottom crossbeam is supported on the poured concrete beam base plate, the top support cylinder is perpendicular to the poured concrete beam base plate. After the angle between the supporting hanger rod and the bottom crossbeam is adjusted, the two are fixed by hydraulic pins.

[0063] To facilitate the adjustment of the length of the support rod, two electric chain hoists 906 can be installed on the side beam. Hanging brackets 907 are installed at both ends of the bottom crossbeam. When it is necessary to adjust the length of the support rod, the alignment pin on the support rod is removed. The two electric chain hoists are connected to the hanging brackets on both sides respectively. The two electric chain hoists are raised and lowered synchronously to raise and lower the bottom crossbeam. After the bottom crossbeam is in place, the alignment pin is locked.

[0064] During the pouring process, the steps for adjusting the working position of the bottom crossbeam of the construction support mechanism are as follows:

[0065] (1) Lift the bottom crossbeam, pull out the hydraulic pins of the support rod and the bottom crossbeam, and pull out the hydraulic pin cylinder of the diagonal tie rod.

[0066] (2) Adjust the working angle between the support rod and the side beam to ensure that the force is perpendicular to the bottom plate of the concrete beam. Then raise the bottom crossbeam to the appropriate fixing hole and insert the hydraulic pin to lock the bottom crossbeam.

[0067] (3) Adjust the length of the support tie rod, insert the hydraulic pin of the tie rod into the fixing hole, and adjust the construction support mechanism into place.

[0068] The machine features a fully equipped working platform, allowing for easy adjustment and installation of construction support mechanisms and anchor bolts from any position on the bridge deck and bottom formwork. It also facilitates inspection of critical components and maintenance of the electrical and hydraulic systems. Key processes and actions such as pin insertion / removal, formwork opening and closing / folding, and overall machine jacking are all hydraulically controlled. Anchor bolts and tie rods are tensioned and raised using hollow jacks, ensuring efficient and convenient operation with low labor intensity.

[0069] The under-deck cantilever bridge construction machine provided in this embodiment is also equipped with a steel cage transporter 11, such as Figure 15 As shown. The rebar cage transporter, located above the bridge deck, is a tire-mounted gantry crane with a cantilever. It lifts precast rebar cages from under the bridge to the bridge deck and installs them into the formwork of the bridge-building machine. The rebar cage transporter includes a tower 1101, a transport main beam 1102, a lifting trolley 1103, and a traveling mechanism 1104, as shown. Figure 16 As shown, the traveling mechanism is installed at the bottom of the tower and supported on the bridge deck. The main transport beam is fixed longitudinally to the tower and extends outwards. The lifting trolley is installed on the main transport beam and moves longitudinally along it. The lifting trolley is equipped with a rotating hoist, which enables the precast steel cage to be lifted from the side of the pier to the bridge. After two 90° turns by the rotating hoist, it is installed into the bridge-building machine's mold bed. During lifting, the rear end of the tower is anchored to the bridge deck by the transport anchor rod 1105 to prevent tipping. The tire-type transporter has various travel modes, including straight, oblique, figure-eight, semi-figure-eight, and in-situ rotation. The in-situ rotation mode ensures that the transporter can turn and turn around within the limited space of the bridge deck, allowing one steel cage transporter to perform steel cage lifting work for two bridge-building machines, improving efficiency while saving equipment operating costs.

[0070] It should be noted that when constructing segment 1 of the under-deck cantilever bridge construction machine, two bridge construction machines are working simultaneously at both ends of the bridge deck. At this time, the side beams on the same side of the two bridge construction machines are connected with connecting bolts. For the remaining segments, the two bridge construction machines are separated.

[0071] The construction method of the under-deck cantilever bridge building machine provided in this embodiment includes the following steps:

[0072] Step 1:

[0073] (1) The pouring of segment #1 has been completed;

[0074] (2) After the concrete beam segment reaches the strength standard, longitudinal slide rails and longitudinal movement cylinders are installed on the bridge deck of the poured concrete beam;

[0075] Step Two:

[0076] (1) Remove the tie rods connecting the outer formwork system and the inner formwork system, remove the bottom formwork rear inner anchor rod assembly connecting the rear crossbeam of the bottom formwork system and the cast-in-place concrete beam, and remove the upper anchor rod assembly connecting the side beam, the cast-in-place concrete beam and the saddle beam.

[0077] (2) The mold opening cylinder at the inner mold system retracts, causing the side support frame and side template of the inner mold system to be demolded and retracted;

[0078] (3) The support cylinder installed on the saddle beam is retracted, and the two bridge building machines are lowered and demolded synchronously. The outer mold system is lowered by about 150mm, so that the slide seat at the bottom of the saddle beam is supported on the longitudinal slide rail of the bridge deck. When the whole machine is lowered and demolded, the inner mold system is also lowered and demolded. That is, the connection between the front end of the support beam of the inner mold system and the front suspension beam is removed. The middle part of the support beam is suspended on the top plate of the front end of the freshly poured concrete beam. The rear end of the support beam is suspended and does not move. The support beam is moved longitudinally along the channel into the interior of the freshly poured concrete beam.

[0079] (4) Disconnect the connection between the side mold system and the bottom mold system. The wing mold is connected to the transverse slide on the side beam by a sliding pair. The hydraulic cylinder pulls the wing mold of the outer mold system to open outward by about 100mm.

[0080] Step 3:

[0081] (1) Install the overspan support wheel set at the rear end of the side beam, ensuring that the overspan support wheel set is supported under the flange plate of the already poured concrete beam, and insert the locking pin.

[0082] (2) Loosen the connecting bolts between the side beams of the two bridge-building machines to separate the two bridge-building machines;

[0083] (3) The longitudinal hydraulic cylinders of the two bridge-building machines push forward, moving the bridge-building machines forward across the span respectively;

[0084] Step Four:

[0085] (1) After the longitudinal movement across the span is completed, the construction support mechanism is installed on the hinged seat below the rear of the side beam;

[0086] (2) The top support cylinder of the construction support mechanism extends out and is supported on the bottom plate of the poured concrete beam, so that the overspan support wheel group is suspended in the air. Remove the locking pin of the overspan support wheel group and turn the overspan support wheel group outward so that it is separated from the support surface.

[0087] Step 5:

[0088] (1) The top support cylinder of the construction support mechanism cooperates with the support cylinder installed on the saddle beam to raise the bridge building machine as a whole by about 150mm until the height of the outer formwork system is in place, and the longitudinal slide rails on the bridge surface are moved to both sides.

[0089] (2) Install the inner anchor rod assembly of the bottom formwork connecting the rear crossbeam of the bottom formwork system to the already poured concrete beam, and install the upper anchor rod assembly connecting the side beam and the saddle beam. Adjust the construction support mechanism into place (the top support cylinder is vertically supported on the bottom plate of the concrete beam).

[0090] (3) The hydraulic cylinder installed on the side beam pushes the outer mold system inward by about 100mm until the outer mold system is in place;

[0091] (4) Adjust each anchor bolt assembly and adjust the outer formwork system to meet the construction requirements of segment 2. Connect the outer formwork system and the bottom formwork system, and pre-tighten the inner anchor bolt assembly of the bottom formwork connecting the crossbeam and the poured concrete beam.

[0092] Step Six:

[0093] (1) When the steel cage transporter travels to the bridge deck directly above the pier, it turns 90° in place, anchors the rear end of the tower to the bridge deck, and lifts the steel cage that has been pre-tied under the bridge.

[0094] (2) After the steel cage is lifted to the bridge deck, rotate it 90° and the crane trolley moves backward to retract the steel cage.

[0095] (3) Then release the anchor bolts, rotate the steel cage transporter 90° in place, and then move forward to the bridge building machine position;

[0096] (4) The rear end of the steel cage transporter is anchored to the bridge deck, and the crane trolley moves forward to move the steel cage directly above segment 2.

[0097] (5) Rotate the steel cage 90°, lower the hoisting trolley, and hoist the steel cage into the formwork.

[0098] (6) After the steel cage is in place in the formwork, connect the steel cage with the reserved steel bars of the previous segment and tie the stirrups at the lap joint.

[0099] Step Seven:

[0100] (1) The support beam of the inner formwork system is moved longitudinally along the duct to the front hanging beam and connected to it. The middle hanging of the support beam is removed, and the inner formwork system is moved longitudinally into the steel cage. The opening cylinder of the inner formwork system is lifted, and the inner formwork system is adjusted to the construction state of segment 2.

[0101] (2) Install the connections between the inner and outer formwork systems, between the inner formwork system and the already poured concrete beam, and between the inner formwork system and the front lifting beam;

[0102] (3) Begin the pouring of the current segment #2. The construction steps for segment #2 are the same as those for segment #1. The only difference is that in steps three and four, it is not necessary to install the overspan support mechanism and the construction support mechanism. The installed overspan support mechanism and the construction support mechanism can be adjusted directly.

Claims

1. A cantilever bridge construction machine, comprising at least a saddle beam, side beams, an outer formwork system, an inner formwork system, and a bottom formwork system. The saddle beam includes a main beam arranged transversely and two hanging beams connected to the bottom of both ends of the main beam. The two hanging beams form a C-shape with the main beam. A sliding seat is installed at the bottom of the main beam. The sliding seat is installed on a longitudinal slide rail set on the bridge deck of the cast-in-place concrete beam. A longitudinal movement cylinder is connected between the sliding seat and the longitudinal slide rail. Under the action of the longitudinal movement cylinder, the saddle beam slides longitudinally along the bridge deck. The hanging beams extend to below the flange plate of the cast-in-place concrete beam. The side beams slide longitudinally... Two side beams are provided, each connected to a hanging beam and located below the flange of the cast-in-place concrete beam. The two side beams extend to the front of the cast-in-place concrete beam, and their front ends are connected to a transversely arranged front hanging beam. The outer formwork system's wing formwork is mounted on the side beams. A longitudinally arranged support beam is fixed to the inner formwork system, with its front end supported by the front hanging beam and its rear end suspended from the top plate of the cast-in-place concrete beam. The front crossbeam of the bottom formwork system is suspended from the front hanging beam, and its rear crossbeam is suspended from the side beams and the bottom plate of the cast-in-place concrete beam. Its characteristic is that: The bottom of the saddle beam is also equipped with a support cylinder. During the pouring and the reversing of the force system when passing through the hole, the support cylinder supports the saddle beam. When passing through the hole, the support cylinder retracts, and the bridge-building machine is supported by the slide block onto the longitudinal slide rail of the bridge deck. Under the action of the longitudinal movement cylinder, it pushes forward to pass through the span. The top of the rear end of the side beam is hinged to a span support wheel set. The span support wheel set can be flipped. When passing through the hole, the span support wheel set is flipped and supported under the flange plate of the already poured concrete beam. During the pouring construction, the span support wheel set is flipped to detach from the already poured concrete beam. A construction support mechanism is installed at the rear of the side beam. The construction support mechanism includes: The bottom crossbeam is arranged transversely and located below the bottom plate of the cast-in-place concrete beam. A top support cylinder is installed on the top of the bottom crossbeam. During the pouring and through-hole inversion of the force system, the top support cylinder is supported on the bottom plate of the cast-in-place concrete beam and is perpendicular to the bottom plate of the cast-in-place concrete beam. The support rods are provided in two parts. The top ends of the two support rods are hinged to the bottom of the rear end of the side beam, and the bottom ends of the two support rods are respectively connected to the two ends of the bottom crossbeam. The support rods are provided with pin holes. The bottom ends of the support rods are connected to the sleeves provided at the ends of the bottom crossbeams. The support rods move up and down along the sleeves. The alignment pins are connected to the pin holes of the support rods and the bottom crossbeams, thereby adjusting the length of the support rods. The support diagonal brace consists of two rods, the bottom ends of which are hinged to the two ends of the bottom crossbeam, and the top ends of which are hinged to the side beam; the support diagonal brace is an adjustable telescopic rod. The boom rotation assembly includes two hydraulic cylinders, which are inclinedly hinged between the supporting booms and the side beams on both sides. The hydraulic cylinders extend and retract to adjust the angle between the supporting booms and the bottom crossbeam.

2. The under-bearing cantilever bridge construction machine according to claim 1, characterized in that: The under-deck cantilever bridge construction machine is equipped with a steel cage transporter, which is located above the bridge deck.

3. The under-bearing cantilever bridge-building machine according to claim 1, characterized in that: During the pouring process, an upper anchor bolt assembly connects the side beams and the saddle beams.

4. The construction method of the under-bearing cantilever bridge construction machine according to claim 1, characterized in that... Includes the following steps: Step 1: After the pouring of segment #1 is completed and the concrete beam segment reaches the required strength, install longitudinal sliding rails and longitudinal hydraulic cylinders at both ends of the poured concrete beam. Step 2: The two bridge-building machines descend and demold; Step 3: Install the span support wheel group on the side beam so that the rear of the side beam is supported on the already poured concrete beam; disconnect the connection between the two bridge building machines and move the two bridge building machines forward longitudinally across the span. At this time, the outer formwork system and the bottom formwork system cross the span together with the saddle beam and the side beam, and the inner formwork system is suspended on the newly poured concrete beam. Step 4: After the longitudinal movement across the span is completed, install and adjust the construction support mechanism, with the span support wheel assembly suspended in the air; Step 5: Raise the bridge-building machine to the height of the outer formwork system and install the outer formwork system and bottom formwork system in place to meet the construction requirements of segment #2; adjust the construction support mechanism so that it is supported on the bottom plate of the already poured concrete beam; Step 6: Hoist the steel cage to segment #2 and place it in the formwork, then connect the steel cage to the reserved steel bars of the previous segment; Step 7: Insert the inner formwork system into the steel cage and adjust the inner formwork system to the construction state of segment #2; Step 8: Begin pouring the concrete for the current segment #2.

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