Method for erecting precast beam of small-span reservoir dam bridge

Abstract

The application is a kind of small-span reservoir dam bridge precast beam erection method, comprising the following steps: S1, assembling and moving forward through the hole of the bridge erecting machine; S2, transporting and erecting the precast beams of the first three spans; S3, transporting and stacking the precast beams of the subsequent spans; S4, continuing to move forward by two spans of the bridge erecting machine, and completing the erection of the precast beams of the two spans by using the precast beams previously stacked, and moving the remaining precast beams not erected to the precast beams of the two spans; S5, repeating S4 until the front support leg moves to the bridge tail, and completing the erection of the precast beams of the last two spans; S6, moving forward and removing the bridge erecting machine. The application has high construction efficiency, good economy and high safety.

Description

Technical Field

[0001] This invention relates to the field of water conservancy engineering construction technology, and in particular to a method for erecting precast beams for small-span reservoir dam bridges. Background Technology

[0002] A dam is a water-retaining structure that blocks the flow of water in rivers and canals to raise the water level or regulate the flow. In addition to gates and auxiliary buildings, dams typically have a bridge connecting the two banks for vehicle and pedestrian traffic. The bridge usually uses T-beams or other types of precast concrete beams, with both ends of the precast beams erected above gate piers on the spillway. The span of the precast beam is equal to the distance between the gate piers, i.e., the width of the gate. Erecting precast beams using crawler cranes is difficult due to limited dam space and insufficient load-bearing capacity; therefore, bridge erecting machines are often used. The conventional method for erecting bridge girders involves assembling the machine at the bridgehead, moving it to the first span, transporting precast beams to the bridgehead by a beam transport vehicle, and then erecting the first span of precast beams. The machine is then moved to the second span, the beam transport vehicle transports precast beams to the first span of the bridge deck, and the machine erects the second span of precast beams. This process is repeated, span by span, until the last span is erected. However, this traditional method of erecting bridge girders span by span has the following problems:

[0003] 1. The beam transport vehicle needs to transport the precast beams along the erected precast beam bridge deck to the tail of the bridge erecting machine for beam feeding. The load-bearing capacity of the precast beams cannot meet the requirements for the beam transport vehicle to pass through. The precast beams need to be reinforced or other temporary measures need to be taken to allow the beam transport vehicle to pass through. This increases the amount of temporary measures and is not economically viable.

[0004] 2. The bridge erecting machine needs to move forward multiple times to erect precast beams one span at a time, which is a complicated process and has a long construction period. After each span of the bridge is erected, the bridge erecting machine needs to stop work and wait for the erected precast beams to be reinforced or other temporary measures to be taken, which adds a lot of extra construction time.

[0005] 3. Transporting beams along the erected bridge deck and adding temporary measures are all high-altitude operations, which are highly dangerous. Summary of the Invention

[0006] The present invention aims to address the shortcomings of the prior art by providing a method for erecting precast beams for small-span reservoir dam bridges.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: a method for erecting precast beams for small-span reservoir dam bridges, comprising the following steps:

[0008] S1. Assembly and forward movement of the bridge erecting machine through the hole;

[0009] The main body of the dam and the gate piers were constructed. A crawler crane was used to assemble the bridge erecting machine at the bridgehead of the dam. The bottom of the bridge erecting machine was equipped with front support legs, middle support legs and rear support legs in sequence. After the bridge erecting machine was assembled, it was moved forward. The front support legs were moved to the third gate pier, the middle support legs were moved to the first gate pier, and the rear support legs were erected at the bridgehead.

[0010] S2, transportation and erection of the first three spans of precast beams;

[0011] The beam transport vehicle transports the precast beams to the space between the rear and middle support legs, and the bridge erecting machine sequentially erects the precast beams for the first, second, and third spans.

[0012] S3, subsequent transport and stacking of precast beams;

[0013] Continue to use beam transport vehicles to transport the precast beams of the subsequent spans that have not yet been erected to the bridgehead, and use bridge erecting machines to stack the precast beams of the subsequent spans that have not yet been erected onto the precast beams of the second and third spans that have already been erected;

[0014] S4. The bridge erecting machine continues to move forward two spans and uses the previously stacked precast beams to complete the erection of the precast beams for the two spans. The remaining precast beams that have not yet been erected are then moved onto the precast beams for the two spans.

[0015] S5. Repeat S4 until the front support leg moves to the end of the bridge, completing the erection of the last two spans of precast beams.

[0016] S6. The bridge erecting machine is moved forward and dismantled;

[0017] After the rear outriggers of the bridge erecting machine were moved to the end of the bridge, the machine was dismantled using a crawler crane, completing the erection of all precast beams for the dam bridge.

[0018] Specifically, the span of the reservoir dam bridge should be ≤20m and the number of spans should be ≤9.

[0019] In particular, the spread distance between the front and middle legs of the bridge erecting machine and between the middle and rear legs is greater than twice the span of the dam bridge. The lateral net distance between a pair of front legs, a pair of middle legs, and a pair of rear legs is greater than the lateral width of the dam bridge deck.

[0020] Specifically, when precast beams that have not yet been erected are stacked, temporary supports and temporary bracing are provided between adjacent layers of precast beams. The temporary supports are set on the top of the lower layer of precast beams and are on the same vertical line as the permanent supports of the bottommost precast beam that has already been erected. The temporary bracing is set on the top of the precast beams and is located on both sides of the temporary supports to support the flanges of the upper layer of precast beams.

[0021] The beneficial effects of this invention are:

[0022] 1. The beam transport vehicle does not need to transport beams on the precast beam bridge deck that has already been erected. The beam transport vehicle only needs to transport the precast beams to the bridgehead for feeding in one go. Therefore, there is no need to add extra temporary measures for beam transport and feeding, which is economical.

[0023] 2. The bridge erecting machine moves forward two spans at a time, simplifying the construction process and shortening the precast beam erection period by half. Moreover, the bridge erecting machine does not need to stop work to wait for the erected precast beams to be reinforced or other temporary measures to be taken. The bridge erecting machine can continue to erect until all precast beams are erected, which greatly shortens the construction cycle.

[0024] 3. Apart from setting up temporary supports and temporary brackets for stacking precast beams, there are no other high-altitude operations during the precast beam erection process, resulting in high construction safety. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of step S1 of the installation method of the present invention;

[0026] Figure 2 This is a schematic diagram of step S2 of the installation method of the present invention;

[0027] Figure 3 This is a schematic diagram of step S3 of the installation method of the present invention;

[0028] Figure 4 This is a schematic diagram of the bridge erecting machine moving forward two spans in step S4 of the erection method of the present invention;

[0029] Figure 5 This is a schematic diagram of the precast beams after they have been moved forward and stacked in step S4 of the erection method of the present invention.

[0030] Figure 6 This is a schematic diagram of the front outrigger after it has been moved to the end of the bridge in step S5 of the erection method of the present invention.

[0031] Figure 7 This is a schematic diagram of the bridge erecting machine after completing the erection of the last two spans of precast beams in S5 of the erection method of the present invention.

[0032] Figure 8 This is a schematic diagram of step S6 of the installation method of the present invention;

[0033] Figure 9 This is a schematic diagram showing the positions of temporary supports and temporary bracing during the stacking of precast beams in the erection method of this invention;

[0034] In the diagram: 1-Crawler crane; 2-Gate pier; 3-Bridge erecting machine; 31-Front outrigger; 32-Middle outrigger; 33-Rear outrigger; 4-Beam transport vehicle; 5-Precast beam; 51-Temporary support; 52-Temporary bracing; 53-Permanent support;

[0035] The following will describe in detail, with reference to the accompanying drawings, embodiments of the present invention. Detailed Implementation

[0036] The present invention will be further described below with reference to embodiments:

[0037] A method for erecting precast beams for small-span reservoir dam bridges includes the following steps:

[0038] S1, Bridge erecting machine 3 assembly and forward movement through the hole, refer to Figure 1 ;

[0039] The main body of the dam and gate piers 2 are constructed. At the bridgehead of the dam, a crawler crane 1 is used to assemble a bridge erecting machine 3. The bottom of the bridge erecting machine 3 is equipped with a front support leg 31, a middle support leg 32, and a rear support leg 33 in sequence. After the bridge erecting machine 3 is assembled, it is moved forward, with the front support leg 31 moved to the third gate pier 2, the middle support leg 32 moved to the first gate pier 2, and the rear support leg 33 erected at the bridgehead. The bridge erecting machine 3 moves two spans directly. Compared with moving one span at a time, this reduces the number of times the bridge erecting machine 3 moves and the time spent moving, thereby shortening the construction period.

[0040] S2, the transportation and erection of the first three spans of precast beams, refer to... Figure 2 ;

[0041] The beam transport vehicle 4 transports the precast beam 5 between the rear support leg 33 and the middle support leg 32, and the bridge erecting machine 3 erects the precast beam 5 in the first span, the second span and the third span in sequence.

[0042] S3, subsequent transport and stacking of precast beams 5, refer to... Figure 3 ;

[0043] Continue to use the beam transport vehicle 4 to transport the precast beams 5 of the subsequent spans that have not yet been erected to the bridge head, and use the bridge erecting machine 3 to stack the precast beams 5 of the subsequent spans that have not yet been erected onto the precast beams 5 of the second and third spans that have already been erected;

[0044] The beam transport vehicle 4 does not need to transport beams on the bridge deck of the precast beams 5 that have already been erected. The beam transport vehicle 4 only needs to transport the precast beams 5 to the bridgehead for feeding in one go. Therefore, there is no need to add extra temporary measures for beam transport and feeding, which is economical. Since it is a small-span reservoir dam bridge, the number of remaining precast beams 5 is not large, and the precast beams 5 that have already been erected can support them.

[0045] S4. The bridge erecting machine 3 continues to move forward two spans and uses the previously stacked precast beams 5 to complete the erection of the precast beams 5 for these two spans. The remaining unerected precast beams 5 are then moved onto the precast beams 5 for these two spans, as per [reference needed]. Figure 4 , Figure 5 ;

[0046] S5. Repeat S4 until the front support leg 31 moves to the end of the bridge, completing the erection of the last two spans of precast beam 5. Refer to... Figure 6 , Figure 7Because the number of precast beams is relatively small and each movement involves two spans, rapid and continuous construction can be achieved, reducing construction interruption time and improving overall construction efficiency. Rapid and continuous construction reduces the waiting time for construction personnel, increases personnel utilization, and reduces labor costs.

[0047] S6. Bridge erecting machine 3 is moved forward and dismantled, refer to... Figure 8 ;

[0048] After the rear outrigger 33 of the bridge erecting machine 3 is moved to the end of the bridge, the crawler crane 1 is used to dismantle the bridge erecting machine 3, thus completing the erection of all the precast beams 5 of the dam bridge.

[0049] The span of the reservoir dam bridge should be ≤20m and the number of spans should be ≤9.

[0050] The spread distance between the front support leg 31 and the middle support leg 32 of the bridge erecting machine 3, as well as the spread distance between the middle support leg 32 and the rear support leg 33, is greater than twice the span of the dam bridge. The lateral net distance between a pair of front support legs 31, a pair of middle support legs 32, and a pair of rear support legs 33 is greater than the lateral width of the dam bridge deck.

[0051] Reference Figure 9 When precast beams 5 are stacked but not yet erected, temporary supports 51 and temporary supports 52 are provided between adjacent layers of precast beams 5. The temporary supports 51 are set on top of the lower layer of precast beams 5 and are on the same vertical line as the permanent supports 53 of the bottommost precast beam 5 that have already been erected. The temporary supports 52 are set on top of the precast beams 5 and are located on both sides of the temporary supports 51 to support the flanges of the upper layer of precast beams 5. During the erection of precast beams 5, apart from setting up the temporary supports 51 and temporary supports 52 for stacking precast beams 5, there are no other high-altitude operations, resulting in high construction safety.

[0052] Example 1

[0053] The span of the reservoir dam bridge is ≤20m, and the number of spans is 7.

[0054] A method for erecting precast beams for small-span reservoir dam bridges includes the following steps:

[0055] S1, Bridge erecting machine 3 assembly and forward movement through the hole, refer to Figure 1 ;

[0056] After the main structure of the dam and gate piers 2 are constructed, the bridge erecting machine 3 is assembled at the bridgehead using crawler crane 1. The bottom of the bridge erecting machine 3 is provided with front support leg 31, middle support leg 32 and rear support leg 33 in sequence. After the bridge erecting machine 3 is assembled, it is moved forward, and the front support leg 31 is moved to the third gate pier 2, the middle support leg 32 is moved to the first gate pier 2, and the rear support leg 33 is erected at the bridgehead.

[0057] S2, the transportation and erection of the first three spans of precast beams, refer to... Figure 2 ;

[0058] The beam transport vehicle 4 transports the precast beam 5 to the rear support leg 33 and the middle support leg 32 at the tail of the bridge erecting machine 3 at the bridgehead, and uses the bridge erecting machine 3 to erect the precast beam 5 in the first span, the second span and the third span in sequence.

[0059] S3, subsequent transport and stacking of precast beams 5, refer to... Figure 3 ;

[0060] Continue to use the beam transport vehicle 4 to transport the precast beams 5 of the subsequent spans that have not yet been erected to the bridge head, and use the bridge erecting machine 3 to stack the precast beams 5 of the subsequent spans that have not yet been erected onto the precast beams 5 of the second and third spans that have already been erected;

[0061] S4. The bridge erecting machine 3 continues to move forward two spans, moving the front support leg 31 of the bridge erecting machine 3 to the fifth span pier 2, the middle support leg 32 to the third span pier 2, and the rear support leg 31 to the first span pier 2; using the precast beams 5 stacked on the second and third spans by the bridge erecting machine 3, they are erected onto the fourth and fifth spans. At the same time, the remaining unerected precast beams 5 are stacked onto the precast beams 5 that have been erected in the fourth and fifth spans, as per the reference. Figure 4 , Figure 5 ;

[0062] S5. Repeat S4. The bridge erecting machine 3 continues to move forward two spans, moving the front support leg 31 to the rear of the bridge, the middle support leg 32 to the fifth span pier 2, and the rear support leg 33 to the third span pier 2. Using the bridge erecting machine 3, the precast beams 5 stacked on the fourth and fifth spans are then erected onto the sixth and seventh spans. (Refer to...) Figure 6 , Figure 7 ;

[0063] S6. Bridge erecting machine 3 is moved forward and dismantled, refer to... Figure 8 ;

[0064] After the rear outrigger 33 of the bridge erecting machine 3 is moved to the end of the bridge, the crawler crane 1 is used to dismantle the bridge erecting machine 3, thus completing the erection of all the precast beams 5 of the dam bridge.

[0065] In this invention, the beam transport vehicle 4 does not need to transport beams on the already erected precast beam 5 bridge deck. The beam transport vehicle 4 only needs to transport the precast beam 5 to the bridgehead for feeding in one go. Therefore, there is no need to add extra temporary measures for beam transport and feeding, which is economical. The bridge erecting machine 3 moves forward two spans at a time, which simplifies the construction process and shortens the erection period of the precast beam 5 by half. Moreover, the bridge erecting machine 3 does not need to stop work to wait for the already erected precast beam 5 to be reinforced or other temporary measures to be taken. The bridge erecting machine 3 can continue to erect until all precast beams 5 are erected, which greatly shortens the construction cycle. During the erection of the precast beam 5, there is no other high-altitude work except for setting up temporary supports 51 and temporary supports 52 for stacking the precast beam 5, which ensures high construction safety.

[0066] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0067] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0068] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0069] The present invention has been described above by way of example. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any improvements made by adopting the inventive concept and technical solution of the present invention, or direct application to other occasions without modification, are all within the protection scope of the present invention.

Claims

1. A method for erecting precast beams for small-span reservoir dam bridges, characterized in that, Includes the following steps: S1, Bridge erecting machine (3) assembly and forward movement through the hole; The main body of the dam and gate piers (2) are constructed. A crawler crane (1) is used to assemble a bridge erecting machine (3) at the bridgehead of the dam. The bottom of the bridge erecting machine (3) is provided with front support leg (31), middle support leg (32) and rear support leg (33) in sequence. After the bridge erecting machine (3) is assembled, it is moved forward. The front support leg (31) is moved to the third gate pier (2), the middle support leg (32) is moved to the first gate pier (2), and the rear support leg (33) is erected at the bridgehead. S2, the first three spans of precast beams (5) are transported and erected; The beam transport vehicle (4) transports the precast beam (5) between the rear support leg (33) and the middle support leg (32), and the bridge erecting machine (3) erects the precast beam (5) of the first span, the second span and the third span in sequence; S3, subsequent transport and stacking of precast beams (5); Continue to use the beam transport vehicle (4) to transport the precast beams (5) of the subsequent spans that have not been erected to the bridge head, and use the bridge erecting machine (3) to stack the precast beams (5) of the subsequent spans that have not been erected onto the precast beams (5) of the second and third spans that have been erected. S4. The bridge erecting machine (3) continues to move forward two spans and uses the previously stacked precast beams (5) to complete the erection of the two spans of precast beams (5). The remaining unerring precast beams (5) are then moved onto the two spans of precast beams (5). S5. Repeat S4 until the front support leg (31) moves to the end of the bridge, completing the erection of the last two spans of precast beams (5); S6. The bridge erecting machine (3) is moved forward and dismantled; After the rear outrigger (33) of the bridge erecting machine (3) is moved to the end of the bridge, the bridge erecting machine (3) is dismantled by the crawler crane (1) to complete the erection of all the precast beams (5) of the dam bridge.

2. The method for erecting precast beams for small-span reservoir dam bridges according to claim 1, characterized in that, The span of the reservoir dam bridge should be ≤20m and the number of spans should be ≤9.

3. The method for erecting precast beams for small-span reservoir dam bridges according to claim 1, characterized in that, The spread distance between the front leg (31) and the middle leg (32) of the bridge erecting machine (3) and the spread distance between the middle leg (32) and the rear leg (33) are greater than twice the span of the dam bridge. The lateral net distance between a pair of front legs (31), a pair of middle legs (32), and a pair of rear legs (33) is greater than the lateral width of the dam bridge deck.

4. The method for erecting precast beams for small-span reservoir dam bridges according to claim 1, characterized in that, When the precast beams (5) that have not been erected are stacked, temporary supports (51) and temporary supports (52) are provided between the two adjacent layers of precast beams (5). The temporary supports (51) are set on the top of the lower layer of precast beams (5) and are on the same vertical line as the permanent supports (53) of the bottom layer of precast beams (5) that have been erected. The temporary supports (52) are set on the top of the precast beams (5) and are located on both sides of the temporary supports (51) to support the wing plates of the upper layer of precast beams (5).

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