Construction method of downstream permanent traffic bridge of hydropower station

Abstract

The invention discloses a construction method for a downstream permanent traffic bridge of a hydropower station. The construction method comprises the following steps: 1, first-stage cofferdam construction; 2, construction of a first-stage bridge substructure; 3, bridge prefabrication and first-stage bridge installation; 4, filling an artificial island in the river and transferring second-stage construction equipment; 5, filling a second-stage upstream cofferdam by using the first-stage cofferdam demolition material; 6, second-stage construction equipment is transferred to the opposite bank; seventhly, the remaining part of the second-stage cofferdam is constructed; 8, a second-stage bridge lower structure is constructed, and a second-stage bridge is installed; and 9, finishing the construction of the downstream permanent traffic bridge of the hydropower station. According to the method, the first-stage cofferdam is used for filling the artificial island in the river, the parking requirement of second-stage construction mechanical equipment is met, then the first-stage cofferdam demolition materials are used for filling the second-stage cofferdam, the artificial island is communicated with a second-stage bank slope, and the equipment parked on the artificial island is transferred to a second-stage river opposite bank for second-stage remaining cofferdam filling and second-stage bridge construction. Therefore, the traffic bridge construction channel arrangement scheme is improved, and the overall construction progress is accelerated.

Description

Technical Field

[0001] The invention belongs to the technical field of permanent traffic bridge construction for dams, and in particular relates to a construction method of a permanent traffic bridge downstream of a hydropower station. Background Art

[0002] In the construction of large hydropower stations, dam construction is usually carried out in two phases, that is, the first phase cofferdam is filled to make one side of the dam have dry land working conditions inside the cofferdam. After completing this part of the construction, the first phase cofferdam is removed and the second phase cofferdam is filled to make the other side of the dam have dry land working conditions inside the second phase cofferdam. In this way, the overall construction of the project is completed in two phases. In order to meet the traffic needs of the left and right banks during the second phase construction and operation period of the hydropower station, a permanent traffic bridge is usually designed downstream of the dam. The construction progress of the bridge directly determines the overall construction progress of the project. The construction method of permanent traffic bridge is similar to that of river-blocking dam, and it also needs to be carried out in two phases. The first phase of construction is located on the same side as the first phase of dam construction. The construction organization can use the resources of the first phase of dam construction, and there is no major problem. However, the second phase of construction organization is limited by the river, and resource organization and transportation will be greatly restricted. To solve this problem, it is usually adopted to build access roads and another set of temporary facilities on one side of the second phase of construction to meet the needs of the second phase of construction, or to build a temporary bridge across the river to meet the temporary passage of the two sides of the permanent bridge construction, and then dismantle it after completion. Both construction methods require a large cost to complete. Therefore, a safe, feasible, fast-paced and low-cost construction method for the construction of a permanent traffic bridge downstream of a hydropower station is needed. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a construction method for a permanent traffic bridge downstream of a hydropower station in view of the deficiencies in the above-mentioned prior art, wherein a first-phase cofferdam is used to fill an artificial island in the river to meet the parking needs of second-phase construction machinery and equipment, and then the demolished materials of the first-phase cofferdam are used to fill the second-phase cofferdam, connecting the artificial island with the second-phase bank slope, so that the equipment parked on the artificial island can be transported to the other side of the second-phase river for filling the remaining cofferdam of the second phase and construction of the second-phase bridge. In this way, the layout plan of the traffic bridge construction channel is improved, the overall construction progress is accelerated, and it is convenient for promotion and use.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is: a method for constructing a permanent traffic bridge downstream of a hydropower station, characterized in that the method comprises the following steps:

[0005] Step 1: Construction of the first phase cofferdam: According to the construction design, the left bank bridgehead road and prefabrication site are constructed within the left bank flooding line. At the same time, the first phase cofferdam is constructed and the first phase cofferdam is drained to ensure that the first phase cofferdam has dry land working conditions;

[0006] Step 2: Construction of the first-phase bridge substructure: completing the construction of the first-phase bridge substructure within the first-phase cofferdam according to the construction design requirements, wherein the first-phase bridge substructure includes pier foundations, piers, cap beams and top pad stones;

[0007] Step 3: Bridge prefabrication and first-phase bridge installation: Bridge prefabrication begins in the prefabrication yard while the first-phase bridge substructure is being constructed. When the first-phase bridge substructure is completed and the conditions for beam erection are met, a bridge erection machine or truck crane is used to install the first-phase prefabricated beams to construct the first-phase bridge;

[0008] Step 4: Filling of artificial island in the river and transportation of equipment for the second phase of construction: When the construction of the substructure of the first phase of the bridge is about to be completed, the artificial island is filled in the lower bend section downstream of the first phase of the cofferdam using the road on the top of the first phase of the cofferdam. The area on the top of the artificial island meets the parking requirements for equipment required for the second phase of construction. After the filling of the artificial island is completed, the equipment for the second phase of construction is transported to the upper part of the artificial island for parking;

[0009] Step 5: Use the demolition materials of the first-stage cofferdam to fill the second-stage upstream cofferdam: After the construction of the first-stage bridge substructure is completed, the first-stage cofferdam is dismantled, and the demolition materials after the demolition of the first-stage cofferdam are used to fill the second-stage upstream cofferdam of the second-stage cofferdam, so that it is connected with the second-stage bank slope within the right bank flooding line;

[0010] Step 6: Transfer the Phase II construction equipment to the other side: Use the Phase II upstream cofferdam of the Phase II cofferdam to transfer the Phase II construction equipment to the other side of the Phase II river, and build the right bank bridgehead road;

[0011] Step 7: Construction of the remaining part of the second phase cofferdam: Use the second phase construction equipment to take materials from the opposite bank of the second phase river to carry out the second phase downstream cofferdam filling and cofferdam waterfront slope protection construction, and carry out the second phase cofferdam pumping and drainage construction to make the inner side of the second phase cofferdam have dry land working conditions;

[0012] Step 8: Construction of the substructure of the second-phase bridge and installation of the second-phase bridge: First, the substructure of the second-phase bridge is constructed in the second-phase cofferdam, and then the beam erection of the second-phase bridge is carried out. After all prefabricated beams are installed, the superstructure of the bridge is immediately constructed;

[0013] Step 9. Construction of the permanent traffic bridge downstream of the hydropower station is completed: After all construction of the first-phase bridge and the second-phase bridge is completed, the construction of the permanent traffic bridge downstream of the hydropower station is completed, the project completion acceptance is organized, and the artificial island and the second-phase cofferdam are dismantled.

[0014] The above-mentioned method for constructing a permanent traffic bridge downstream of a hydropower station is characterized in that the artificial island is arranged in the lower bend section of the longitudinal section of the first-phase cofferdam to reduce river scouring.

[0015] The above-mentioned method for constructing a permanent traffic bridge downstream of a hydropower station is characterized in that: in step five, during the removal of the first-phase cofferdam, the removal starts from its downstream cofferdam section and proceeds from the bank slope to the center of the river.

[0016] The above-mentioned method for constructing a permanent traffic bridge downstream of a hydropower station is characterized in that: in step eight, during the construction of the lower structure of the second-phase bridge, concrete is transported to the end of the first-phase bridge where the beams have been erected by a concrete tanker, unloaded using a chute, and poured at the top of the second-phase cofferdam in conjunction with a pumping system and a pump pipe.

[0017] The above-mentioned method for constructing a permanent traffic bridge downstream of a hydropower station is characterized in that: in step four, the materials required for the second-phase cofferdam filling and the second-phase construction are transported to the end of the bridge through the first-phase bridge with the erected bridge deck, and then the lifting equipment is arranged on the artificial island for reverse transportation.

[0018] Compared with the prior art, the present invention has the following advantages:

[0019] 1. The present invention constructs a left bank bridgehead road and a prefabrication site within the left bank flooding line according to the construction design, and constructs a first-phase cofferdam at the same time, and completes the construction of the first-phase bridge substructure within the first-phase cofferdam. When the construction of the first-phase bridge substructure is completed and the conditions for beam erection are met, a bridge erection machine or a truck crane is used to install the first-phase prefabricated beams to construct the first-phase bridge, thereby providing a construction foundation for subsequent construction.

[0020] 2. The present invention utilizes the road on top of the first-phase cofferdam to build an artificial island in the lower curved section downstream of the first-phase cofferdam. The top area of ​​the artificial island meets the parking requirements for equipment required for the second-phase construction. The demolished materials of the first-phase cofferdam are used to build the second-phase upstream cofferdam to connect it with the second-phase slope within the right bank inundation line. The second-phase upstream cofferdam of the second-phase cofferdam is used to transport the second-phase construction equipment to the other side of the second-phase river, thereby solving the problem of completing the transportation of second-phase construction materials when no temporary facilities are arranged on one side of the second-phase construction project of the hydropower station, no second-phase access road is built, and no temporary bridge across the river is built.

[0021] 3. The method of the present invention has simple steps, the construction process is less difficult to operate, is easy to promote, and has less interference with each other. The overall mechanization degree of the construction is high, which can reduce the amount of temporary construction projects and is very beneficial to speeding up the overall progress of the construction. The construction efficiency is high, and it can effectively speed up the overall progress of the project and the construction progress of the permanent traffic bridge, reduce construction costs, and is easy to promote and use.

[0022] To sum up, the present invention utilizes the first-phase cofferdam to build an artificial island in the river to meet the parking needs of the second-phase construction machinery and equipment, and then utilizes the demolished materials of the first-phase cofferdam to build the second-phase cofferdam, connecting the artificial island with the second-phase slope, so that the equipment parked on the artificial island can be transported to the other side of the second-phase river for filling the remaining cofferdam of the second phase and construction of the second-phase bridge. This improves the layout plan of the traffic bridge construction channel, speeds up the overall construction progress, and facilitates popularization and use.

[0023] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is the overall construction layout diagram of the present invention.

[0025] Figure 2 This is a schematic diagram of the second phase cofferdam filling of the present invention.

[0026] Figure 3 This is a schematic diagram of the second phase construction of the present invention.

[0027] Figure 4 The figure is a flowchart of the method of the present invention.

[0028] Description of reference numerals:

[0029] 1—bridgehead road on the left bank; 2—bridgehead road on the right bank; 3—flooding line on the left bank;

[0030] 4—right bank flooding line; 5—first-stage cofferdam; 6—second-stage cofferdam;

[0031] 7—Phase I bridge substructure; 8—Phase II bridge substructure; 9—Prefabrication yard;

[0032] 10—artificial island; 11—first phase bridge; 12—pumping system;

[0033] 13—Pump tube. DETAILED DESCRIPTION

[0034] like Figures 1 to 4 As shown, a method for constructing a permanent traffic bridge downstream of a hydropower station of the present invention comprises the following steps:

[0035] Step 1, construction of the first phase cofferdam: according to the construction design, the left bank bridgehead road 1 and the prefabrication site 9 are constructed within the left bank flooding line 3, and the first phase cofferdam 5 is constructed at the same time, and the first phase cofferdam 5 is pumped and drained to ensure that the first phase cofferdam 5 has dry land working conditions;

[0036] Step 2, construction of the first-phase bridge substructure: completing the construction of the first-phase bridge substructure 7 within the first-phase cofferdam 5 according to the construction design requirements, wherein the first-phase bridge substructure 7 includes a pier foundation, a pier, a cap beam and a top pad stone;

[0037] Step 3: Bridge prefabrication and first-phase bridge installation: Bridge prefabrication is started in the prefabrication yard 9 while the first-phase bridge substructure 7 is under construction. When the first-phase bridge substructure 7 is completed and the conditions for beam erection are met, a bridge erection machine or a truck crane is used to install the first-phase prefabricated beams to construct the first-phase bridge 11.

[0038] Step 4: Filling of the artificial island in the river and transportation of the second-phase construction equipment: When the construction of the first-phase bridge substructure 7 is about to be completed, the first-phase cofferdam 5 top road is used to fill the artificial island 10 at the lower bend section downstream of the first-phase cofferdam 5. The top area of ​​the artificial island 10 meets the parking requirements of the equipment required for the second-phase construction. After the filling of the artificial island 10 is completed, the second-phase construction equipment is transported to the upper part of the artificial island 10 for parking;

[0039] Step 5: Use the demolition materials of the first-stage cofferdam to fill the second-stage upstream cofferdam: After the construction of the first-stage bridge substructure 7 is completed, the first-stage cofferdam 5 is demolished, and the demolition materials after the demolition of the first-stage cofferdam 5 are used to fill the second-stage upstream cofferdam of the second-stage cofferdam 6, so that it is connected with the second-stage bank slope within the right bank flooding line 4;

[0040] Step 6: Transferring the second-phase construction equipment to the other side: Using the second-phase upstream cofferdam of the second-phase cofferdam 6, transfer the second-phase construction equipment to the other side of the second-phase river, and build the right-bank bridgehead road 2;

[0041] Step 7, construction of the remaining part of the second phase cofferdam: using the second phase construction equipment to take materials on the opposite bank of the second phase river to carry out the second phase downstream cofferdam filling and cofferdam waterfront slope protection construction of the second phase cofferdam 6, and to carry out the second phase cofferdam 6 pumping and drainage construction, so that the inner side of the second phase cofferdam 6 has dry land working conditions;

[0042] Step 8: Construction of the substructure of the second-phase bridge and installation of the second-phase bridge: First, the substructure 8 of the second-phase bridge is constructed in the second-phase cofferdam 6, and then the beam erection of the second-phase bridge is carried out. After all prefabricated beams are installed, the superstructure of the bridge is immediately constructed;

[0043] Step 9. Construction of the permanent traffic bridge downstream of the hydropower station is completed: After all construction of the first-phase bridge 11 and the second-phase bridge 11 is completed, the construction of the permanent traffic bridge downstream of the hydropower station is completed, the project completion acceptance is organized, and the artificial island 10 and the second-phase cofferdam 6 are dismantled.

[0044] It should be noted that according to the construction design, the left bank bridgehead road and prefabrication yard are constructed within the left bank inundation line, and the first-phase cofferdam is constructed at the same time to complete the construction of the first-phase bridge substructure within the first-phase cofferdam. When the construction of the first-phase bridge substructure is completed and the conditions for beam erection are met, a bridge erection machine or a truck crane is used to install the first-phase prefabricated beams to build the first-phase bridge, providing a construction foundation for subsequent construction; the first-phase cofferdam top road is used to fill an artificial island in the lower bend section downstream of the first-phase cofferdam. The top area of ​​the artificial island meets the parking requirements for the equipment required for the second-phase construction. The demolished materials of the first-phase cofferdam are used to fill the second-phase upstream cofferdam to make it aligned with the right bank The second phase slope within the inundation line is connected, and the second phase construction equipment is transferred to the other side of the second phase river by using the second phase upstream cofferdam of the second phase cofferdam, so as to solve the problem that the second phase construction materials can be transported when no temporary facilities are arranged on one side of the second phase project of the hydropower station, no second phase access road is built, and no temporary bridge across the river is built; the construction process is less difficult to operate and easy to promote, and there is less interference between each other. The overall mechanization degree of construction is high, which can reduce the amount of temporary construction projects and is very beneficial to speeding up the overall progress of construction. The construction efficiency is high, which can effectively speed up the overall progress of the project and the construction progress of the permanent traffic bridge, and reduce construction costs.

[0045] In this embodiment, the artificial island 10 is arranged at the lower curved section of the longitudinal section of the first-stage cofferdam 5 to reduce river scouring.

[0046] In this embodiment, in step five, during the dismantling process of the first-stage cofferdam 5, the dismantling starts from its downstream cofferdam section and proceeds from the bank slope toward the center of the river.

[0047] In this embodiment, in step eight, during the construction of the second-phase bridge substructure 8, concrete is transported to the end of the first-phase bridge 11 where the beams have been erected by a concrete tanker, unloaded using a chute, and poured at the top of the second-phase cofferdam 6 in conjunction with the pumping system 12 and the pump pipe 13.

[0048] In this embodiment, in step 4, the materials required for the second-phase cofferdam filling and the second-phase construction are transported to the end of the bridge through the first-phase bridge 11 with the bridge deck erected, and then the lifting equipment is arranged on the artificial island 10 for reverse transportation.

[0049] When the present invention is used, the first-phase cofferdam is used to fill an artificial island in the river to meet the parking needs of the second-phase construction machinery and equipment, and then the demolished materials of the first-phase cofferdam are used to fill the second-phase cofferdam, connecting the artificial island with the second-phase bank slope, so that the equipment parked on the artificial island can be transported to the other side of the second-phase river for filling the remaining cofferdam of the second phase and construction of the second-phase bridge. This improves the layout plan of the traffic bridge construction channel and speeds up the overall construction progress.

[0050] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent structural change made to the above embodiment based on the technical essence of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A method for constructing a permanent traffic bridge downstream of a hydropower station, characterized in that: The method comprises the following steps: Step 1: Construction of the first phase cofferdam: According to the construction design, the left bank bridgehead road (1) and the prefabrication site (9) are constructed within the left bank flooding line (3), and at the same time, the first phase cofferdam (5) is constructed, and the first phase cofferdam (5) is pumped and drained to ensure that the first phase cofferdam (5) has dry land working conditions; Step 2: Construction of the first-phase bridge substructure: According to the construction design requirements, the construction of the first-phase bridge substructure (7) within the first-phase cofferdam (5) is completed, wherein the first-phase bridge substructure (7) includes a pier foundation, a pier, a cap beam and a top pad stone; Step 3: Bridge prefabrication and first-phase bridge installation: Bridge prefabrication is started in the prefabrication yard (9) while the first-phase bridge substructure (7) is being constructed. When the first-phase bridge substructure (7) is completed and the conditions for beam erection are met, a bridge erection machine or a truck crane is used to install the first-phase prefabricated beams to construct the first-phase bridge (11). Step 4: Filling of an artificial island in the river and transportation of equipment for the second phase of construction: When the construction of the first phase bridge substructure (7) is about to be completed, an artificial island (10) is filled in the lower bend section downstream of the first phase cofferdam (5) using the road on the top of the first phase cofferdam (5). The top area of ​​the artificial island (10) meets the parking requirements for equipment required for the second phase of construction. After the filling of the artificial island (10) is completed, the equipment for the second phase of construction is transported to the upper part of the artificial island (10) for parking; Step 5: Use the demolition materials of the first-stage cofferdam to fill the second-stage upstream cofferdam: After the construction of the first-stage bridge substructure (7) is completed, the first-stage cofferdam (5) is dismantled, and the demolition materials after the demolition of the first-stage cofferdam (5) are used to fill the second-stage upstream cofferdam of the second-stage cofferdam (6) so that it is connected with the second-stage bank slope within the right bank flooding line (4); Step 6: Transferring the Phase II construction equipment to the opposite bank: Using the Phase II upstream cofferdam of the Phase II cofferdam (6), transfer the Phase II construction equipment to the opposite bank of the Phase II river, and build the right bank bridgehead road (2); Step 7, construction of the remaining part of the second phase cofferdam: using the second phase construction equipment to take materials from the opposite bank of the second phase river to carry out the second phase downstream cofferdam filling and cofferdam waterfront slope protection construction of the second phase cofferdam (6), and to carry out the second phase cofferdam (6) pumping and drainage construction, so that the inner side of the second phase cofferdam (6) has dry land working conditions; Step 8: Construction of the substructure of the second-phase bridge and installation of the second-phase bridge: First, the substructure of the second-phase bridge (8) is constructed in the second-phase cofferdam (6), and then the beam erection of the second-phase bridge is carried out. After all prefabricated beams are installed, the superstructure of the bridge is immediately constructed; Step 9. Construction of the permanent traffic bridge downstream of the hydropower station is completed: After all the construction of the first-phase bridge (11) and the second-phase bridge (11) is completed, the construction of the permanent traffic bridge downstream of the hydropower station is completed, and the project completion acceptance is organized, and the artificial island (10) and the second-phase cofferdam (6) are dismantled.

2. A method for constructing a permanent traffic bridge downstream of a hydropower station according to claim 1, characterized in that: The artificial island (10) is arranged at the lower curved section of the longitudinal section of the first-stage cofferdam (5) to reduce river scouring.

3. A method for constructing a permanent traffic bridge downstream of a hydropower station according to claim 1, characterized in that: In step 5, during the dismantling of the first-stage cofferdam (5), the dismantling starts from its downstream cofferdam section and proceeds from the bank slope toward the river center.

4. A method for constructing a permanent traffic bridge downstream of a hydropower station according to claim 1, characterized in that: In step eight, during the construction of the second-phase bridge substructure (8), concrete is transported to the end of the first-phase bridge (11) where the beams have been erected by a concrete tanker, unloaded by a chute, and poured at the top of the second-phase cofferdam (6) in conjunction with a pumping system (12) and a pump pipe (13).

5. A method for constructing a permanent traffic bridge downstream of a hydropower station according to claim 1, characterized in that: In step 4, the materials required for the second-phase cofferdam filling and the second-phase construction are transported to the end of the bridge through the first-phase bridge (11) with the bridge deck already erected, and then the lifting equipment is arranged on the artificial island (10) for reverse transportation.

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