A construction method for small curve and large cross slope segmental box beam

Abstract

The present invention discloses a method for constructing a segmental box girder with a small curve and a large transverse slope, comprising: step one, construction of a segmental box girder with a straight line; step two, installation of a bracket beside a pier, wherein the plane thereof is installed by adjusting and matching with the legs of a bridge erecting machine, and the temporary support is anchored to the legs of the bridge erecting machine through an anchoring system; step three, the bridge erecting machine rotates across the span, a transverse shifting device is provided on the main beam of the bridge erecting machine for transversely shifting the middle legs to the designed position, and an adjusting pad is provided during the movement of the rear legs to adapt to the change of the transverse slope of the segmental box girder; step four, suspension of the segmental box girder, feeding the beam in different ways according to the design at different positions, and the box girder is adjusted and assembled; step five, permanent prestressing; step six, repeating the above steps. The present invention optimizes the anchoring system of the bridge erecting machine, reduces the front-end process of the bridge erecting machine, adapts to the change of the transverse slope of the rear legs, avoids endangering the safety of the rear legs, and the transverse shifting device of the middle legs of the bridge erecting machine avoids the use of a large crane, saves costs, reinforces the existing curved bridge, and facilitates beam feeding.

Description

Technical Field

[0001] The present invention relates to the technical field of municipal bridge construction, and more specifically, to a method for constructing a small-curve, large-cross-slope segmental box girder. Background Art

[0002] In the construction of municipal bridges in developed cities overseas, when constructing the segmental box girder, the existing 12-lane urban traffic trunk road below the box girder has a large traffic volume day and night. The local government requires that the traffic flow must be kept smooth, and only the middle main road is allowed to be closed from 23:00 in the evening to 04:00 the next day, and the construction time is short; the segmental box girder of the short-line matching method of the tail section crosses the existing viaduct, which is a 4-span curve section with a minimum curve radius of R=150m, a maximum transverse slope of 7% and a longitudinal slope of 2% for the box girder, and a length of 22m~40m, all of which are simply supported spans; two LG850 bridge erection machines are used for box girder erection. The specific construction background is shown in the figure below. Figure 2 shown.

[0003] The technical problems that need to be solved during the construction process include: the construction crosses the existing curved viaduct, the beam feeding area is limited, and the beam feeding vehicle needs to drive to the existing bridge, but the existing bridge is old and has insufficient bearing capacity, so it needs to be reinforced; the minimum radius of the segmental box beam curve is R=150m, and the maximum transverse slope is 7%, which makes it difficult for the bridge erection machine to turn and position. The rear outrigger of the bridge erection machine extends out of the existing box beam and cannot support it. When the middle outrigger moves forward, the middle outrigger cannot move horizontally into place; when the bridge erection machine passes through the hole in the second step, the rear outrigger changes due to the transverse slope, causing one side of the outrigger to be suspended in the air, endangering the overall stability of the bridge erection machine; due to the large transverse slope, the conventional anchoring system of the bridge erection machine does not meet the requirements, and the safety of the temporary support is poor. In view of this special working condition, this application proposes a small curve and large transverse slope segmental box beam construction method to solve the above technical problems. Summary of the invention

[0004] One object of the present invention is to provide a method for constructing a segmented box girder with a small curve and a large transverse slope, which solves the above-mentioned technical problems and ensures the overall stability of the bridge crane and the beam body and the convenience of construction.

[0005] In order to solve the above technical problems, the present invention provides a method for constructing a segmental box girder with a small curve and a large transverse slope. The segmental box girder construction includes the construction of a straight section and the construction of a segmental box girder with a small curve and a large transverse slope. The specific construction method includes:

[0006] Step 1: Complete the construction of the straight segment box girder;

[0007] Step 2: Install the bracket and platform beside the pier. The plane of the bracket beside the pier and the legs of the bridge erector are adjusted and installed to match each other. The temporary support and the legs of the bridge erector are anchored by the anchoring system.

[0008] Step 3: The bridge erection machine rotates to cross the span. A transverse movement device is provided on the main beam of the bridge erection machine, on which the middle leg is connected. The transverse movement device is used to transversely move the middle leg to the designed position to adapt to the positioning deviation of the middle leg. In addition, during the movement of the bridge erection machine across the span, the rear leg is moved by setting an adjustment pad to ensure that the rear legs on both sides are uniformly stressed at all times to adapt to the change of the cross slope of the segmental box beam.

[0009] Step 4: Segmental box beam hanging, feeding beams in different ways according to the design at different positions, adjusting and assembling box beams, and wet joint construction;

[0010] Step 5: permanent prestressing, permanent support grouting, temporary support removal;

[0011] Step 6. Repeat the above steps.

[0012] Preferably, the bridge-building machine passing the hole specifically includes: moving the main overhead crane to the rear of the bridge-building machine to serve as a counterweight, removing the connection between the middle leg and the main beam, moving the main beam of the bridge-building machine forward, and supporting the front leg to the pier cap beam in front of the hole to be passed; installing the pier side bracket; continuing to move the main beam of the bridge-building machine forward, supporting the front leg to the pier side bracket; installing the pier top segmental beam in front of the hole to be passed and completing temporary anchoring; supporting the rear auxiliary legs, using the main overhead crane to reverse the rear middle leg to the pier top segmental beam in front of the hole to be passed, and anchoring it to the pier top segmental beam; continuing to move the main beam of the bridge-building machine forward, passing the hole in place, anchoring the main beam of the bridge-building machine and the middle leg, retracting the front leg, preparing to erect the segmental box beam corresponding to the span of the hole to be passed; erecting the assembled segmental box beam, and completing the prestressing tensioning construction.

[0013] Preferably, in the step 2, after the pier side bracket is installed, its plane is parallel to the slope of the cap beam, the front legs of the bridge erection machine are matched with the pier side bracket through the height adjustment pad and the inclined pad, and the pier side bracket is hooked back on the cap beam;

[0014] The temporary support is vertically anchored on the lower cap beam, the front middle leg is anchored on the temporary support, the foot of the middle leg is set as a ball joint structure to adapt to the slope of the segmented box girder for angle adjustment, and the foot of the middle leg and the top surface of the temporary support are also provided with inclined pads for slope adjustment; the pier top block matches the slope of the segmented box girder, and multiple vertical embedded sleeves are pre-embedded on the pier top, which are used to anchor the rear middle leg.

[0015] Preferably, in the step 5, the temporary supports are used to support the load before the prestressing of the whole span is completed, and after the prestressing of the whole span is completed, the permanent supports are constructed, and then the temporary supports are removed, and the loads of all segmental box girders are transferred to the permanent supports to complete the system conversion;

[0016] The temporary support is a self-locking jack with a ball head on the top to form a self-adjusting slope support surface to adapt to the slope of the segmental box girder. Steel pads and steel plates are supported on the self-locking jack to adjust the elevation of the pier top block. A single pier top segmental box girder is installed on multiple sets of temporary supports, and the pier top is quickly anchored to the cap beam through the temporary supports.

[0017] Preferably, the segmental box girder suspension hoisting adopts different construction methods according to different working conditions, specifically: the segmental box girder constructed in the straight section adopts the under-bridge feeding method;

[0018] During the construction of the small curve and large transverse slope section, the beam lifting area under the bridge conflicts with the existing viaduct. The truck crane is used to assist in beam feeding. The segmental box beam is first lifted and placed on the existing viaduct deck by the truck crane, and then the beam is lifted by the bridge erection machine. The area between the existing viaduct and the bridge span is backfilled to form a beam lifting area, or a temporary beam storage platform flush with the existing viaduct is installed at the corresponding position of the pier. The existing viaduct is reinforced and supported by the bracket, and then the segmental box beam is fed onto the bridge.

[0019] For the multi-span bridge deck with a certain angle of transverse slope and the ramp bridge deck with a certain angle of longitudinal slope, the longitudinal and transverse slopes will cause eccentric load when the box girder is suspended. A rotatable hinge seat is set on the suspension, and the transverse beam connected to it is consistent with the longitudinal and transverse slopes of the segmental box girder. In addition, the main overhead crane of the bridge erection machine is designed with a certain lateral displacement on both sides. When hoisting the segmental box girder, the overhead crane is moved laterally to make the center line of the segmental box girder coincide with the theoretical center line of the bridge span.

[0020] Preferably, when constructing a small curve and a large cross slope section, when the bridge-erecting machine passes the span, the rear support leg is moved to the beam surface of the completed segmental box girder by horizontally moving the main beam of the bridge-erecting machine before passing the span, and then the bridge-erecting machine passes through the hole. At this time, an extended section is added to the cross beam of the rear middle support leg so that the main beam of the bridge-erecting machine has sufficient horizontal movement distance. After completing the passing of the hole, the center of the bridge-erecting machine is moved to the middle of the span by horizontally moving the main beam of the bridge-erecting machine.

[0021] Preferably, when all beam sections of the main line are erected, for the construction of small curves and large transverse slope sections, the bridge erection machine moves horizontally to both sides at the end of the marked bridge span to construct the other two box beams. The steps of the bridge erection machine's horizontal movement are as follows: the bridge erection machine completes the erection of the last bridge segment beam, completes the tensioning, and removes the hanging; the bridge erection machine retreats, and the rear auxiliary legs slide on the beam surface until the front auxiliary legs support the brackets beside the piers; retreat the front middle legs to the erected beam surface, and retreat the rear middle legs to the beam surface of the previous span; use a car crane to install temporary supports and variable-length beams on the outside, and anchor them, and anchor the temporary supports to the bridge piers, so that the horizontality of the middle leg beam and the variable-length beam is within the set error range; retract the front auxiliary legs, and simultaneously operate the front and rear leg horizontal movement cylinders to move the bridge erection machine's main beam horizontally, adjust the main beam position, and face the current span center line; continue to retreat the main beam until the main beam is in the center position, anchor the main beam and the middle character, and prepare to erect the beam.

[0022] Preferably, during the construction of a small curved section, since the beam supply under the construction span is limited and tail beam feeding is impossible, beam supply is carried out in the span before the construction span; during the beam supply process of the previous span, the front legs of the bridge erection machine need to pass through the hole to the portal pier cap beam of the previous span and support the front legs to ensure the safety of the beam supply of the previous span.

[0023] Preferably, the rear leg of the bridge-building machine is supported on the completed beam surface when passing through the hole. As the transverse slope angle of the box girder in the small curve segment gradually increases, the rear leg is suspended on one side during the movement. To ensure that the two wheel groups of the rear leg are evenly stressed, steel plates and inclined pads are set under the walking track according to different transverse slopes to ensure that the track is vertical.

[0024] Preferably, the construction method of the transverse movement device is as follows: first, the middle leg is suspended on the main beam of the bridge erection machine through the main overhead crane, and then the middle leg is moved laterally as a whole to a set distance through the transverse movement device provided by the middle leg; after the middle leg is translated, the temporary support is lowered onto the cap beam through the hand winch suspended between the middle leg and the temporary support and anchored with fine-rolled threaded steel bars. After the temporary support is installed, the middle leg is extended through its own oil cylinder, and the middle leg is placed on the temporary support. By adjusting the elongation of the middle leg and the foot plate screw, the middle leg beam is made horizontal and reaches the designed height, and the middle leg and the temporary support are anchored with fine-rolled threaded steel bars.

[0025] The present invention has at least the following beneficial effects:

[0026] 1. Applicability

[0027] This construction method can optimize the anchoring system of the bridge erection machine, reduce the pre-processing steps of the bridge erection machine, adapt to the changes in the lateral slope of the rear outriggers, avoid endangering the safety of the rear outriggers, and use the outrigger transverse movement device in the bridge erection machine to avoid the use of large cranes, save costs, reinforce existing curved bridges, and facilitate beam feeding.

[0028] 2. Economical

[0029] (1) The anchoring system of the bridge erecting machine is optimized to meet the requirement of a large transverse slope of 7%. The pre-processing steps of the bridge erecting machine are reduced, and the construction is efficient.

[0030] (2) The main beam and middle support leg of the bridge erection machine adopt a flat-plate rotating shaft design, which can adapt to 12-degree rotation to the left and right, and realize rapid positioning through small curve holes.

[0031] (3) The temporary anchoring system of the pier top block adopts vertical support and vertical anchoring design, which improves the stability of the beam body against lateral sliding.

[0032] (4) The pier top block support device adopts an adjustable design to meet the requirements for precise positioning of the pier top block. A ball-head flat plate jack is used on the upper part to match the 7% transverse slope of the pier top block.

[0033] (5) The height and cross slope of the rear outrigger wheel assembly and track of the bridge crane can be adjusted to adapt to the changes in slope during the hole-passing process.

[0034] (6) When the middle support leg moves forward through the hole, a transverse movement device is used to enable the middle support leg to move quickly into position.

[0035] (7) The bridge erection machine uses a rotating hanger, a sliding hanger and a shear sleeve to prevent the suspended threaded steel from being sheared.

[0036] (8) The bridge-erecting machine can expand the beam feeding area through various beam feeding methods such as front, mid-span and tail, and realize beam feeding on existing curved sections of elevated bridges, saving the investment in large equipment.

[0037] (9) The sockets between the main beam and the middle leg of the bridge erection machine are designed with a long slot type, so that when the main beam moves horizontally through the hole in a small curve, the main beam and the middle leg can be kept in a single-end anchored state, and the relative rotation of the main beam and the middle leg can be maintained.

[0038] (10) Before the bridge erection machine passes through the hole, the support grouting is carried out first to ensure the overall stability of the box girder. After the box girder is erected, the block construction is carried out in time, and the box girder is tied together with the adjacent box girder as a whole to prevent slippage.

[0039] The construction method of the present invention was successfully applied in the Rama III Expressway project in Thailand, achieving good economic and social benefits.

[0040] Other advantages, objectives and features of the present invention will be embodied in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a construction process flow chart of the present invention;

[0042] Figure 2 It is the construction background diagram of the present invention;

[0043] Figure 3 This is a plan view of the transportation and hoisting of the segmental box girder of the present invention by a truck crane;

[0044] Figure 4 This is a schematic diagram of the suspension of the segmental beam with a 7% cross slope according to the present invention;

[0045] Figure 5 This is the first step of the transverse movement construction of the bridge erecting machine of the present invention;

[0046] Figure 6 This is the second step of the transverse movement construction of the bridge erecting machine of the present invention;

[0047] Figure 7 This is the third step of the transverse movement construction of the bridge erecting machine of the present invention;

[0048] Figure 8 This is the fourth step of the transverse movement construction of the bridge erecting machine of the present invention;

[0049] Fig. 9 This is the fifth step of the transverse movement construction of the bridge erecting machine of the present invention;

[0050] Fig.10 This is the sixth step of the transverse movement construction of the bridge erecting machine of the present invention;

[0051] Fig.11 This is a schematic diagram of the main beam positioning of the MLP11-19-MLP11-20L span bridge erecting machine of the present invention;

[0052] Fig.12 This is a schematic diagram of the main beam positioning of the MLP11-20-MLP11-21L span bridge erecting machine of the present invention;

[0053] Fig.13 This is a schematic diagram of the main beam positioning of the MLP11-21-MLP11-22L span bridge erecting machine of the present invention;

[0054] Fig.14 This is a schematic diagram of the main beam positioning of the MLP11-22-MLP11-23L span bridge erecting machine of the present invention;

[0055] Fig.15 This is a diagram of the temporary support and cap beam and front middle leg anchoring system of the present invention;

[0056] Fig.16 This is a diagram of the anchoring system of the supporting legs and the pier top block in the present invention;

[0057] Fig.17 It is a plane comparison diagram before and after the supporting legs move forward in the present invention. DETAILED DESCRIPTION

[0058] In order to better understand the purpose, structure and function of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings so that those skilled in the art can implement it according to the description.

[0059] It should be noted that the experimental methods described in the following embodiments are conventional methods unless otherwise specified, and the reagents and materials are commercially available unless otherwise specified; in the description of the present invention, the terms "lateral", "longitudinal", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0060] The small curved section box girder of this application has a 7% transverse slope. In order to ensure the overall stability of the bridge crane and the beam and the convenience of construction, on the basis of the straight section plan, the anchoring system of the bridge crane, the anchoring system of the pier top block, and the lateral movement of the middle leg into position are optimized to facilitate the lateral movement of the middle leg, the reinforcement of the existing curved bridge, and the slope adjustment device of the rear middle leg through the hole.

[0061] like Figure 1 The figure shows the process flow chart of segmental box girder construction.

[0062] 1. The main construction steps of curved box girder installation are demonstrated as follows:

[0063] Step 1: Remove the box girder hanging of piers 10-11-10-12 and prepare for the hole.

[0064] Step 2: Move the main beam forward and support the front legs onto the cap beams of piers 10-13; use the auxiliary overhead crane to install the brackets beside piers 10-13.

[0065] Step 3: Continue to move the main beam forward and support the front legs onto the brackets next to piers 10-13.

[0066] Step 4: Use the main overhead crane to install the pier top segment beams 10-13 and complete temporary anchoring.

[0067] Step 5: Support the rear auxiliary legs, use the main overhead crane to transport the rear middle legs to the top segment beams of piers 10-13, and anchor them on the top segment beams of piers.

[0068] Step 6: Continue to move the main beam forward, put the hole into place, anchor the main beam and the middle leg, retract the front leg, and prepare to erect the span segment beam of piers 10-12 to 10-13.

[0069] Step 7: Hang all the segmental box girders of the entire span on the main beam of the bridge erection machine in turn, and finally leave some segmental beams for staggered hanging; after the hanging is completed, use the main overhead crane to splice all the segmental beams in turn from the small inner layer direction, and complete the temporary prestressing construction.

[0070] Step 8: (1) After the installation of the entire span segment box girder is completed, start installing the external prestressed steel strands;

[0071] (2) Install wet joint formwork and complete wet joint concrete pouring;

[0072] (3) After the wet joint concrete strength reaches 15Mpa, permanent prestressing construction begins;

[0073] (4) After the prestressing tensioning construction is completed, the grouting construction of the steel plate on the support of piers 10-13 will begin;

[0074] (5) After the strength of the bearing grouting material reaches the design strength, start to remove the temporary bearings and constraints to complete the system conversion;

[0075] (6) The construction of the box girder of this span is completed, the hanging parts are removed, the hole is prepared, and the erection of the box girder of the next span segment begins.

[0076] 2. Installation and construction of pier top segmental beams.

[0077] The connection method of the side piers, middle piers and cap beams in this application is pot-type support. Before the prestressing of the whole span is completed, the temporary support is used to support the force. After the prestressing of the whole span is completed, the temporary support is removed, and the load of all segmental beams is transferred to the permanent support to complete the system conversion. The installation of the first pier top segmental beam needs to be carried out by a truck crane.

[0078] 1. The pier side bracket and operating platform are installed and removed using the auxiliary overhead crane or truck crane provided by the bridge erection machine. The main installation steps are as follows:

[0079] Using a bridge erection machine to assist an overhead crane or a truck crane, workers first pass six 40mm diameter fine-rolled threaded steel bars through the reserved holes on the cap beam, install the anti-hook structure on the opposite side of the bracket and fix the threaded steel bars with nuts.

[0080] The bridge erection machine assists the overhead crane or truck crane to lift the bracket to the standing side of the front legs of the bridge erection machine, and the bracket falls on the top surface of the cap beam.

[0081] Anchor the threaded steel bar to the bracket's hanger, but do not tighten the nut at this time.

[0082] Use wooden wedges to fill the gap between the steel plate below the bracket and the concrete surface of the cap beam to make the bracket fit tightly against the cap beam.

[0083] Tighten the nuts anchored on the threaded steel bars between the cap beam and the bracket, use a through-hole jack to apply 50T prestress to each piece of precision-rolled threaded steel bar, tighten the nuts, and hook the fixed bracket back onto the top surface of the cap beam to complete the installation.

[0084] Before the first step through the hole in the small curve and large cross slope section, the pier side bracket is installed parallel to the slope of the cap beam, and the front leg of the bridge erection machine is matched with the pier side bracket through the height adjustment pad and the inclined pad.

[0085] 2. Temporary support installation:

[0086] A 400T self-locking jack is used as a temporary support. The top of the self-locking jack has a self-adjusting slope support surface, which can avoid stress concentration on the contact surface between the segmental beam with a transverse slope and the jack, and avoid damage to the segmental beam structure. A single pier top segmental beam is installed on 4 sets of temporary supports. The main overhead crane of the bridge erection machine is used to adjust the position of the pier top segmental beam. The steel pads and steel plates are supported on the self-locking jack to adjust the elevation of the pier top block. At the cap beam position designed with a transverse slope, the bottom surface of the temporary support should fit tightly with the cap beam concrete. Before installing the temporary support, the concrete at the installation position should be checked to avoid unevenness and insufficient contact surface. At the same time, the bottom of the temporary support should be paved with materials with sufficient strength, flexibility and friction. At the same time, the concrete on the top of the cap beam is cut at the support position to keep the temporary support vertical.

[0087] 3. Installation of the pier top beam section. After the preparatory work is completed, the installation of the pier top beam section begins. The specific installation steps are as follows:

[0088] Arrange 4 temporary supports for self-locking jacks according to the layout drawing, and roughly adjust the upper steel support pads and steel plate thickness of the self-locking jacks to the approximate elevation of the segmental beam design installation according to the elevation of the permanent support. The self-locking jacks are pushed out about 2cm to ensure that there is space for the jacks to be recovered when the pier top block is installed;

[0089] The bridge erecting machine lifts the top beam section of the pier to the top of the installation position, and preliminarily adjusts its horizontal and vertical slopes according to the requirements of the design drawings;

[0090] Visually align the longitudinal and transverse axes of the beam section with the longitudinal and transverse axes laid out on the pier top and slowly lower the beam to place it on the self-locking jack;

[0091] The beam segment is roughly adjusted into position by visually checking whether the beam segment axis is aligned with the pier top installation control line. The beam segment rough adjustment may be repeated 1-3 times depending on the beam placement accuracy. The beam segment rough adjustment accuracy is required to be within 10mm of plane deviation and 10mm of elevation deviation;

[0092] Measure the coordinate control points on the top surface of the beam, observe the deviation of the beam section, and sort out the beam section adjustment data;

[0093] According to the measurement data, with the help of auxiliary reference points, the beam section is fine-tuned (fine-tuned) to make it meet the control target requirements in vertical, horizontal and longitudinal directions; the elevation is fine-tuned by using a 400T jack to adjust it to the designed elevation and lock the jack in time. The final target data is collected, fed back to the monitoring unit, reported to the supervision engineer, and confirmed that the final accuracy meets the beam section installation requirements.

[0094] 4. Temporary constraint settings.

[0095] 5. Pier top segment anchoring system.

[0096] The rear middle leg is anchored to the pier top block by four vertical φ36 fine-rolled threaded steel bars, with a single tension of 20t. Four embedded sleeves are set on the pier top block according to the slope. The embedded angle ensures that the hole is vertical after the pier top block is in place.

[0097] At locations where the longitudinal slope of the segmental beam is larger, the reserved hole on the top of the pier top block also matches the longitudinal slope to ensure that after the pier top block is in place, the hole is vertical and can correspond to the middle leg.

[0098] The pier top block is anchored to the cap beam through temporary supports and 4 φ40 finely rolled threaded steel bars. The threaded steel bars are perpendicular to the top surface of the cap beam, and a single threaded steel bar is tensioned by 50t. The temporary support consists of a slide plate and a flat jack, which can fine-tune the installation accuracy of the pier top block. Before installing the temporary support, the top surface of the cap beam at the support position is cut off to ensure the horizontal installation of the support; the top of the flat jack is designed with a ball head, which can adapt to 5.5% full angle adjustment. On the flat jack, an inclined pad is set according to the different cross slopes to ensure a close fit with the ground of the pier top block, such as Fig.16 shown.

[0099] 3. Transportation and suspension of segmental box girders.

[0100] The segmental box girder suspension adopts the under-bridge feeding method, and the box girder hoisting adopts special hoists. Four 40mm diameter fine-rolled threaded steel bars made of PSB930 are used for hoisting. When the box girder is suspended, some beam sections need to be staggered in height so that there is enough construction space for the subsequent box girder splicing.

[0101] (1) Feeding beam under the bridge

[0102] The main line section of this project adopts the method of feeding beams under the bridge to hoist the beam sections. When the segmental box beam is transported to the beam lifting position under the bridge on site, the segmental box beam suspension construction begins. After the box beam of the previous span is dismantled, the hanging will be stored in a convenient installation position on the ground. After the segmental beam arrives at the site, it will be installed and hung using a car crane. The beam transporter will transport the installed hanging segmental beam to the area in front to be lifted, and finally the main overhead crane will lift the segmental beam and hang it to the corresponding position of the main beam. All the beam sections of one span will be hung on the lower chord of the main beam of the bridge erection machine in turn.

[0103] 2) The beam lifting area under the bridge of span MLP11-17–MLP11-20 conflicts with the existing elevated bridge, so it is impossible to lift the beam directly under the bridge. Therefore, a 220T truck crane is required to assist in feeding the beam. First, the truck crane is used to lift the segmental box beam onto the existing elevated bridge deck, and then the bridge erection machine is used to lift the beam. Figure 3 shown.

[0104] For the MLP 11-16 – MLP 11-17 span, the area between the MLP 11-16 – MLP11-17 elevated sections will be backfilled to the same height as the highway. The backfill range is from MLP11-16 to the 15m area with a backfill height of approximately 50cm. The concrete guardrails entering and exiting the Bangkok Expressway will be cut off by approximately 8m. After the beam transporter enters the site, it will drive from the existing highway into the backfill area to carry out beam hanging operations.

[0105] For spans MLP 11-17– MLP 11-18, a temporary beam storage platform was installed in the area between the MLP 11-17–MLP 11-18 viaducts (located at the corresponding position of the highway piers) to the same height as the highway; about 5 meters of concrete guardrails on the highway corresponding to the temporary beam storage platform in and out of Bangkok were cut off; after the beam transporter transported the beam from the viaduct to the current span, a 220T crane was used for the pier top block and a 160T crane was used for the standard section to transport the segmental beam to between the beam storage platform and the existing highway (on the center line of the segmental beam erection) for beam hanging operations.

[0106] For other span feed beams, other spans are affected by the existing curved viaduct, and the feed beam position is close to the existing bridge guardrail, causing the existing bridge to be under eccentric pressure. To ensure the safety of the existing bridge, the existing bridge is reinforced before the beam transport vehicle goes up the bridge, and steel supports are used to support the cap beam next to the two adjacent piers on one side of the feed beam.

[0107] (3) Box girder suspension under special working conditions.

[0108] The maximum transverse slope of the last five spans of the project is 7%, and the longitudinal slope of the ramp is 5.5%. In order to adapt to the eccentric load caused by the longitudinal and transverse slopes when the box beam is suspended, a rotatable hinge is designed on the suspension, and the left and right lateral displacement of the main crane of the bridge erection machine is designed to be 0.5 meters. When the segmental beam is hoisted, the crane can be moved horizontally to make the center line of the box beam coincide with the theoretical center line of the bridge span. When the segmental beam is fixed to the main beam of the bridge erection machine, the suspension crossbeam maintains the same longitudinal and transverse slopes as the segmental beam. When the suspension is connected to the main beam, the hinge is rotated to achieve the purpose of vertical suspension. Figure 4 shown.

[0109] 4. Assembly of segmental box girders.

[0110] During the prefabrication of the segmental box girder segments, anti-arch reserves have been set, and embedded control points have been set on the segmental beams. The control point data have been approved by the consultant, and the segments are assembled on site according to the control point data.

[0111] (1) The steps for assembling beam segments are as follows:

[0112] a) Move the crane crane to the top of the first suspension beam (near the top block of the small inner pier), connect the main hanger on the crane with the suspension hanger with a pin, lift the beam section with the crane crane and loosen the suspension rod. Adjust the elevation, plane position, longitudinal and transverse slope of the box beam to meet the requirements of linear control accuracy.

[0113] b) Install the positioning frame at the wet joint between the suspension beam and the pier top block, lock the suspension beam, tighten the upper and lower nuts of the suspension hanger to make the hanger bear force, unhook the main hoisting device of the bridge erector, and transfer the load of the beam section to the main truss of the bridge erector again.

[0114] c) Move the crane crane to the top of the second suspension beam, connect the main hoist on the crane with the suspension hoist with a pin, lift the second suspension beam and loosen the suspension rod. Adjust the elevation, plane position, longitudinal and transverse slope of the box beam to meet the requirements of linear control accuracy.

[0115] d) The lifting device keeps the longitudinal and transverse slopes unchanged, lifts the beam section to the joint position with the first suspension beam, conducts trial assembly first, and then formally splices after confirming that the two box beams can be fully matched, and tensions the temporary prestress between the first and second suspension beams.

[0116] e) Tighten the upper and lower nuts of the second suspension beam hanger to make the hanger bear force, unhook the main hoisting device of the bridge erection machine, and transfer the load of the beam section to the main truss of the bridge erection machine again.

[0117] f) Complete the assembly of the remaining suspension beam sections in sequence according to the assembly steps for the second suspension beam.

[0118] When assembling and adjusting the position of beam segments, the surveying personnel need to calculate the data that actually needs to be adjusted for installation based on the linear data of the prefabricated segmental beams and the theoretical linear data of the installation. The adjustment of beam segments is a process of repeated adjustments and gradual convergence. Therefore, during construction, the order of longitudinal adjustment → transverse adjustment → vertical adjustment → longitudinal adjustment → transverse adjustment → vertical adjustment is repeated in a cycle until the design requirements are met.

[0119] (2) Temporary prestressing setting.

[0120] (3) Positioning of reference block.

[0121] (4) Wet joint construction.

[0122] (5) Permanent prestressing and grouting.

[0123] (6) Grouting, hanging and temporary restraint release of permanent supports.

[0124] 5. Bridge erecting machine anchoring system.

[0125] like Fig.15As shown, the temporary support is anchored to the lower cap beam through 10 φ36 fine-rolled threaded steel bars, and a single threaded steel bar is tensioned by 20t. The anchored threaded steel bar is perpendicular to the top surface of the cap beam, and the temporary support is perpendicular to the top surface of the cap beam; the front middle leg is placed on the temporary support, and the middle leg crossbeam is horizontal by adjusting the leg height. The middle leg is anchored to the temporary support through 4 φ36 fine-rolled threaded steel bars, and the fine-rolled threaded steel bar and the middle leg are kept vertical. Ball head pads and ball head nuts are set at both ends of the 4 threaded steel bars to ensure that the threaded steel is subjected to axial force and avoid shearing of the threaded steel.

[0126] The middle outrigger foot adopts a ball joint design, which can adapt to 5% full angle adjustment. A 7% inclined pad is set between the foot and the top surface of the temporary support to adjust the slope. The top surface of the temporary support is horizontally welded with an anti-slip steel plate to enhance the anti-slip safety factor between the middle outrigger and the temporary support. The main beam of the bridge crane and the middle outrigger socket adopt a long slot design.

[0127] 6. Bridge erection machine through the hole.

[0128] Before the bridge erection machine passes through the hole, the support grouting is first carried out to ensure the overall stability of the box beam. After the box beam is erected, the block construction is carried out in time, and the box beam is tied with the adjacent box beam as a whole to prevent slippage. Since the longitudinal prestressed pipe grouting does not affect the bridge erection machine through the hole construction, after the longitudinal prestressing of the box beam is completed, the installation construction of the next span of the box beam will begin. The construction steps of the bridge erection machine through the hole are as follows:

[0129] (1) Temporary prestressing and box girder hanging and removal

[0130] The order of temporary prestress removal is opposite to that of temporary prestress tensioning. When removing, first install the reaction frame, then use the through-hole jack to apply a tensioning force slightly greater than that during tensioning, then use a wrench to remove the nut, and finally unload the jack to complete the removal of all temporary prestress. When removing the suspension, first use the main suspension of the bridge crane crane to connect to the box girder suspension, then use a wrench to loosen the suspension nut hanging on the main beam, and finally remove the threaded steel. The crane will transfer the suspension to the bottom of the bridge for storage, and then complete the removal of all box girder suspensions in sequence.

[0131] (2) Bridge erection machine through hole

[0132] Before the bridge crane passes through the hole, it is necessary to clean up the debris on the main beam to prevent it from falling due to vibration during the hole passing process, which may cause safety hazards. The main construction steps for the standard span bridge crane are as follows:

[0133] The main overhead crane moves to the tail of the bridge erecting machine to serve as a counterweight;

[0134] Remove the connector between the center leg and the main beam;

[0135] Install the longitudinal movement device between the middle outrigger and the main beam;

[0136] The main beam is moved longitudinally in the direction of greater mileage to the maximum cantilever length;

[0137] Support the rear outrigger to the bridge deck behind the rear middle outrigger;

[0138] After the crane is transferred, the middle leg is placed on the segment beam at the top of the pier of the leading span;

[0139] Anchor the rear middle leg and the pier top cap beam, and install the longitudinal movement device of the rear middle leg and the main beam;

[0140] Continue to move the main beam longitudinally into place;

[0141] The front middle leg is anchored to the rear middle leg and the main beam to complete the bridge erection machine through-hole construction.

[0142] Before crossing the span, check the installation status of the tension screws of the pier side bracket and ensure that the pier side bracket is hooked on the cap beam to avoid shearing of the threaded steel bar. If any problems are found, correct them in time.

[0143] The radius of the 5 spans of the main line at the end of the mark is R=200m. It is necessary to consider the movement trajectory of the rear outrigger when the bridge erector passes the span to ensure that the rear outrigger meets the support conditions when passing the span. Take the MLP11-21 - MLP11-22L span as an example for demonstration. Before the bridge erector passes the span, the rear outrigger needs to be moved to the beam surface where the segmental beam has been erected by moving the main beam horizontally before passing the hole. At this time, the rear middle outrigger crossbeam has an extended section to meet the sufficient main beam horizontal movement distance. After the hole is completed, the center of the bridge erector is moved to the middle of the span by moving the main beam horizontally.

[0144] like Fig.17 As shown in the figure, due to the small radius of the curve, the main truss of the bridge erecting machine passes through the hole in the first step, and the rotation angle of the main truss is not enough to rotate directly into position. Therefore, the installation position of the pier side bracket is offset 1.5m to the outside of the arc compared to the positioning position of the main truss to ensure that the main truss can be placed on the pier side bracket after rotation.

[0145] During the forward movement of the middle outrigger, the center deviation between the main beam and the middle outrigger was 1.5m. It was difficult to achieve the middle outrigger in place by only relying on the ±50cm lateral movement of the overhead crane. Therefore, a set of lateral movement devices was installed on the main truss, and the middle outrigger was hung on the main truss through the main overhead crane. Then, the middle outrigger was moved 1.5m horizontally as a whole through the lateral movement device of the middle outrigger. After the middle outrigger was horizontally moved, the temporary support was lowered to the cap beam and anchored with fine-rolled threaded steel bars through the four 8t hand winches suspended between the middle outrigger and the temporary support. After the temporary support was installed, the middle outrigger extended the outrigger through its own oil cylinder and placed it on the temporary support. By adjusting the extension of the outrigger and the foot plate screw, the crossbeam of the middle outrigger was made horizontal and reached the designed height, and the middle outrigger and the temporary support were anchored with fine-rolled threaded steel bars.

[0146] The transverse slope of the segment beam gradually transitions from 2.5% to 7%. When the rear outrigger of the bridge erector passes through the hole in the second step, it is supported on the completed beam surface. The transverse slope gradually increases, causing the rear outrigger to be suspended on one side during the movement, resulting in an unstable state of the rear outrigger. In order to ensure that the two wheel groups of the rear outrigger are evenly stressed, steel plates and inclined pads are set under the walking track according to different transverse slopes to ensure the track is vertical.

[0147] When the rear outrigger is in motion, according to the idea of ​​"short distance, frequent adjustment", a special person is arranged to check the horizontality of the rear outrigger beam. If the level ruler is found to be uneven, the movement is stopped immediately, and the height of the walking track is adjusted before resuming the through-hole construction.

[0148] 7. Horizontal movement construction of the bridge erecting machine.

[0149] When all the beam sections of the main line are erected, the bridge erection machine will be moved horizontally to both sides at the end of the MLP11-23-MLP11-24 span to construct the other two box beams. The steps of the bridge erection machine's horizontal movement are as follows.

[0150] like Figure 5 As shown, the bridge erection machine has completed the erection of the last span bridge segment beam, completed the tensioning, and removed the hanging;

[0151] like Figure 6 As shown, the bridge erecting machine retreats, and the rear auxiliary outrigger slides on the beam surface until the front auxiliary outrigger supports the bracket beside the pier;

[0152] like Figure 7 As shown, the front middle leg is retracted to the erected beam surface, and the rear middle leg is retracted to the beam surface of the previous span;

[0153] like Figure 8 As shown, a temporary support and a luffing beam are installed on the outside by using a truck crane, and the anchorage is set, and the temporary support is anchored on the bridge pier so that the horizontality of the middle leg beam and the luffing beam is within the set error range;

[0154] like Fig. 9 As shown, retract the front auxiliary outriggers, and at the same time operate the front and rear outrigger transverse cylinders to transversely move the main beam of the bridge erecting machine and adjust the main beam position to face the current span centerline;

[0155] like Fig.10 As shown, continue to retract the main beam until it is in the center, anchor the main beam and the center character, and prepare to erect the beam.

[0156] 8. Positioning of the main beam of the small curve bridge erecting machine

[0157] 1. Under normal construction conditions, the main beam of the bridge erection machine is positioned so that the center of the main beam passes through the span to the center of the construction span before the beam erection construction is carried out. In the small curve construction of this project, since the beam supply under the construction span is limited and the tail beam cannot be fed, it is necessary to supply the beam in the span before the construction span. In the beam supply scheme of the previous span, the front legs of the bridge erection machine need to pass through the hole to the portal pier cap beam of the previous span and support the front legs to ensure the safety of the beam supply of the previous span. The span and main beam positioning parameters of the bridge erection machine using the previous span beam supply condition are as follows in Table 1:

[0158] Table 1 Span and main beam positioning parameters of the bridge erection machine for the previous span beam supply condition

[0159]

[0160] MLP11-19—MLP11-20L main beam positioning diagram for cross-bridge erection machine, such as Fig.11 shown.

[0161] MLP11-20—MLP11-21L main beam positioning diagram for cross-bridge erection machine, such as Fig.12 shown.

[0162] MLP11-21—MLP11-22L main beam positioning diagram for cross-bridge erection machine, such as Fig.13 shown.

[0163] MLP11-22—MLP11-23L main beam positioning diagram for cross-bridge erection machine, such as Fig.14 shown.

[0164] When the entire span transverse prestressing is tensioned and grouting is completed and the strength of the grouting material reaches 100% of the design strength, the dismantling of the suspension begins. The order of dismantling the suspension is: dismantling of the suspension and temporary prestressing → dismantling of the overhead crane → dismantling of the main beam → dismantling of the legs. During dismantling, a 130t crawler crane is used to dismantle each suspension component in turn, and each suspension component is transported to the next portal pier area to be constructed.

[0165] 2. The transverse and longitudinal slopes of the segmental beam erection construction at the end of the bid vary greatly, and the height of the outriggers will change accordingly in each step of the construction of each span. Therefore, the height of the outriggers will only be demonstrated for each step of the construction span with a longitudinal slope of 5.5% and a transverse slope of 7%.

[0166] (1) When constructing on a 5.5% longitudinal slope, the height of the outriggers should be adjusted

[0167] Taking RON5-16L–RON5-17L as an example, the construction of segmental beams was completed and the construction of RON5-15L–RON5-16L began. The longitudinal slope was designed to be 5.5%.

[0168] During the erection phase of the RON5-16L–RON5-17L segmental beams, the height of each outrigger is adjusted, the front outrigger and the rear outrigger are retracted to the unsupported state, and the front middle outrigger and the rear middle outrigger are adjusted in height.

[0169] In the first through-hole stage of RON5-15L–RON5-16L, the height of each leg is adjusted, the rear leg is recovered to the unsupported state, and the front middle leg and the rear middle leg and the front leg are adjusted in height.

[0170] During the forward movement phase of the middle outriggers for RON5-15L–RON5-16L, the height of each outrigger is adjusted, the front outrigger is retracted to the unsupported state, and the front middle outrigger, rear middle outrigger and rear outrigger are adjusted in height.

[0171] In the second step of the through-hole stage for RON5-15L–RON5-16L, the height of each outrigger is adjusted, the front outrigger is retracted to an unsupported state, the front middle outrigger, the rear middle outrigger and the rear outrigger are adjusted in height, and the rear outrigger is completely retracted 10m after passing through the hole without support.

[0172] After the second step of passing the hole is completed, the bridge erection machine will carry out segmental beam erection construction in this state. After completing the erection construction, continue the construction of the next span with the above steps.

[0173] (2) When constructing on a 7% cross slope, the height of the bridge erection machine legs should be adjusted

[0174] The cross slope construction mainly considers the height matching of the middle leg and the left and right legs. Taking the MLP11-24-MLP11-25 segment beam erection construction stage as an example, the cross slope is designed to be 7%.

[0175] During the construction phase of the MLP11-24–MLP11-25 segment beam erection, each leg is height-adjusted, and the left and right legs of the front center leg and the rear center leg are height-adjusted with a certain height difference.

[0176] It is understood that the present invention is described by some embodiments, and those skilled in the art are aware that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation mode, and they can be fully applied to various fields suitable for the present invention. For those familiar with the art, other modifications can be easily implemented, so without departing from the general concept defined by the claims and the equivalent scope, the present invention is not limited to the specific details and the illustrations shown and described here.

Claims

1. A method for constructing a small curve and large cross slope segment box girder, characterized in that: Segmental box girder construction includes straight section construction and small curve and large cross slope section construction. The specific construction methods include: Step 1: Complete the construction of the straight segment box girder; Step 2: Install the bracket and platform beside the pier. The plane of the bracket beside the pier and the legs of the bridge erector are adjusted and installed to match each other. The temporary support and the legs of the bridge erector are anchored by the anchoring system. Step 3: The bridge erecting machine rotates to cross the span. A transverse movement device is provided on the main beam of the bridge erecting machine, to which the front middle leg or the rear middle leg is connected. The transverse movement device is used to transversely move the front middle leg or the rear middle leg to the designed position to adapt to the positioning deviation of the front middle leg or the rear middle leg. In addition, during the movement of the bridge erecting machine across the span, the rear leg is moved by setting an adjustment pad to ensure that the rear legs on both sides are uniformly stressed at all times to adapt to the change of the cross slope of the segment box beam. Step 4: Segmental box beam hanging, feeding beams in different ways according to the design at different positions, adjusting and assembling box beams, and wet joint construction; Step 5: permanent prestressing, permanent support grouting, temporary support removal; Step 6. Repeat the above steps; When all the beam sections of the main line are erected, for the small curve and large cross slope section, the bridge erection machine moves horizontally to both sides at the end of the span to construct the other two box beams. The steps of the bridge erection machine moving horizontally are as follows: The bridge erection machine completes the erection of the last span bridge segment beam, completes the tensioning, and removes the hanging; The bridge erecting machine moves back, and the rear auxiliary outrigger slides on the beam surface until the front auxiliary outrigger supports the bracket beside the pier; Move back the front middle leg to the erected beam surface, and move back the rear middle leg to the beam surface of the previous span; Use a truck crane to install temporary supports and luffing beams on the outside, set their anchors, and anchor the temporary supports to the piers, so that the horizontality of the front middle outrigger or rear middle outrigger beam and the luffing beam is within the set error range; Retract the front auxiliary outriggers, and at the same time operate the front outrigger transverse movement cylinders and the rear outrigger transverse movement cylinders to transversely move the main beam of the bridge erecting machine and adjust the main beam position to face the current span centerline; Continue to retract the main beam until it is in the center position, anchor the main beam to the front center support leg and the rear center support leg, and prepare to erect the beam.

2. The method for constructing a small curve and large transverse slope segment box girder according to claim 1, characterized in that: The bridge erection machine through-hole specifically includes: The main overhead crane is moved to the tail of the bridge erecting machine to act as a counterweight, the connection between the front middle leg and the rear middle leg and the main beam is removed, the main beam of the bridge erecting machine is moved forward, and the front leg is supported to the pier cap beam in front of the hole to be passed; Install pier side brackets; Continue to move the main beam of the bridge erecting machine forward and support the front outriggers onto the brackets beside the piers; Install the pier top segment beam in front of the hole to be passed and complete temporary anchoring; Support the rear auxiliary legs, use the main crane to transport the rear middle legs to the pier top segment beam in front of the hole to be passed, and anchor them on the pier top segment beam; Continue to move the main beam of the bridge erector forward, pass through the hole in place, anchor the main beam of the bridge erector to the front middle leg and the rear middle leg, retract the front leg, and prepare to erect the segmental box beam corresponding to the span to be passed through the hole; Erect and assemble segmental box girders and complete prestressing construction.

3. The method for constructing a small curve and large transverse slope segment box beam according to claim 1, characterized in that: In the step 2, after the pier side bracket is installed, its plane is parallel to the slope of the cap beam, the front legs of the bridge erection machine are matched with the pier side bracket through the height adjustment pad and the inclined pad, and the pier side bracket is hooked back on the cap beam; The temporary support is vertically anchored on the lower cap beam, the front middle leg and the rear middle leg are anchored on the temporary support, the feet of the front middle leg and the rear middle leg are set as ball hinge structures to adjust the angle of the adaptive segment box beam slope, and the feet of the front middle leg and the rear middle leg and the top surface of the temporary support are also provided with inclined pads for slope adjustment; The pier top block matches the slope of the segmental box girder, and a plurality of vertical embedded sleeves are pre-embedded on the pier top block, which are used to anchor the front middle leg and the rear middle leg.

4. The method for constructing a small curve and large transverse slope segment box girder according to claim 3, characterized in that: In the step 5, the temporary support is used to support the load before the prestressing of the whole span is completed. After the prestressing of the whole span is completed, the permanent support is constructed, and then the temporary support is removed, and the load of all segmental box girders is transferred to the permanent support to complete the system conversion; The temporary support is a self-locking jack with a ball head on the top to form a self-adjusting slope support surface to adapt to the slope of the segmental box girder. Steel pads and steel plates are supported on the self-locking jack to adjust the elevation of the pier top block. A single pier top segmental box girder is installed on multiple sets of temporary supports, and the pier top block is anchored to the cap beam through the temporary supports.

5. The method for constructing a small curve and large transverse slope segment box beam according to claim 1, characterized in that: The segmental box girder suspension hoisting adopts different construction methods according to different working conditions, specifically: The segmental box girder constructed in the straight section adopts the under-bridge feeding method; During the construction of the small curve and large transverse slope section, the beam lifting area under the bridge conflicts with the existing viaduct. The truck crane is used to assist in feeding the beam. The segmental box beam is first lifted and placed on the deck of the existing viaduct by the truck crane, and then the beam is lifted by the bridge erection machine; the area between the existing viaduct and the bridge span is backfilled to form a beam lifting area, or a temporary beam storage platform flush with the existing viaduct is installed at the corresponding position of the pier; After reinforcing the existing viaduct by installing brackets, the segmental box girder is fed onto the bridge; For the multi-span bridge deck with a certain angle of transverse slope and the ramp bridge deck with a certain angle of longitudinal slope, the longitudinal and transverse slopes will cause eccentric load when the box girder is suspended. A rotatable hinge seat is set on the suspension, and the transverse beam connected to it is consistent with the longitudinal and transverse slopes of the segmental box girder. In addition, the main overhead crane of the bridge erection machine is designed with a certain lateral displacement on both sides. When hoisting the segmental box girder, the overhead crane is moved laterally to make the center line of the segmental box girder coincide with the theoretical center line of the bridge span.

6. The method for constructing a small curve and large transverse slope segment box girder according to claim 1, characterized in that: During the construction of small curve and large cross slope sections, when the bridge-erecting machine passes the span, the rear support leg is moved to the beam surface of the completed segmental box girder by horizontally shifting the main beam of the bridge-erecting machine before passing the span, and then the bridge-erecting machine passes through the hole. At this time, an extended section is added to the cross beam of the rear middle support leg so that the main beam of the bridge-erecting machine has sufficient horizontal shifting distance. After completing the passing of the hole, the center of the bridge-erecting machine is moved to the middle of the span by horizontally shifting the main beam of the bridge-erecting machine.

7. The method for constructing a small curve and large transverse slope segment box beam according to claim 1, characterized in that: During the construction of small curved sections, since the beam supply under the construction span is limited and the tail beam feeding is impossible, beam supply is carried out in the span before the construction span; during the beam supply process of the previous span, the front outrigger of the bridge erection machine needs to pass through the hole to the portal pier cap beam of the previous span and support the front outrigger to ensure the safety of the beam supply of the previous span.

8. The method for constructing a small curve and large transverse slope segment box beam according to claim 1, characterized in that: When the rear outrigger of the bridge erection machine passes through the hole, it is supported on the completed beam surface. As the transverse slope angle of the box girder in the small curve segment gradually increases, the rear outrigger is suspended on one side during the movement. To ensure that the two wheel groups of the rear outrigger are evenly stressed, steel plates and inclined pads are set under the walking track according to different transverse slopes to ensure that the track is vertical.

9. The method for constructing a small curve and large transverse slope segment box girder according to claim 1, characterized in that: The construction method of the transverse shifting device is as follows: first, the middle leg is hung on the main beam of the bridge erecting machine through the main overhead crane, and then the middle leg is moved horizontally as a whole to a set distance through the transverse shifting device provided by the middle leg; after the middle leg is horizontally moved, the temporary support is lowered onto the cap beam through the hand winch suspended between the middle leg and the temporary support and anchored with fine-rolled threaded steel. After the temporary support is installed, the middle leg extends the leg through its own oil cylinder, and the middle leg is placed on the temporary support. By adjusting the elongation of the middle leg and the foot plate screw, the middle leg beam is made horizontal and reaches the designed height, and the middle leg and the temporary support are anchored with fine-rolled threaded steel.

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