Comprehensive construction method for large-diameter heat distribution pipeline to penetrate through large-fall original river channel

Abstract

A comprehensive construction method for a large-diameter heat distribution pipeline to penetrate through a large-fall original river channel comprises the steps that a river channel slope protection on the west side of the river channel is excavated; constructing a steel sheet pile cofferdam, and simultaneously constructing an operation platform and a temporary road; excavation of the foundation pit is carried out, and dewatering and drainage measures are taken; pipeline construction; backfilling the groove; changing the flow of the riverway; constructing a soil pile cofferdam on the east side of the riverway, and constructing a foundation pit support; excavation of the foundation pit is carried out, and dewatering and drainage measures are taken; pipeline construction; and backfilling the foundation pit. The method is suitable for pipeline laying construction of an original ecological river which is high in fall, long in distance, large in excavation depth and complex in geological condition, compared with a traditional cofferdam excavation river crossing method, the method is simple and convenient to construct, the construction procedure is greatly simplified, and meanwhile the construction quality and safety are effectively guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of underground pipeline construction, in particular to a comprehensive construction method for a large-diameter thermal pipeline to cross a native river channel with a large drop. Background Art

[0002] At present, large-diameter long-distance heating pipelines are the development trend of urban centralized heating. The utilization rate of DN1400 and above pipelines in the long-distance heating industry is less than 8%. The development trend of heating pipelines in the future is characterized by larger diameters and longer transmission distances. Longer transmission distances mean that the route will pass through more different and complex areas, such as roads, bridges, buildings, railways and rivers.

[0003] In the long-distance pipeline projects, it is often necessary to cross the river, and the cofferdam excavation is generally used to cross the river. The traditional cofferdam construction is divided into two stages. First, the cofferdam on one side of the river is built. After the construction on this side of the river is completed, the cofferdam is removed and then the cofferdam on the other side of the river is built. This construction method takes a long time and cannot achieve the purpose of quickly crossing the river. Summary of the invention

[0004] The purpose of the present invention is to overcome the above-mentioned defects and propose a comprehensive construction method that can effectively realize the crossing of large-diameter pipelines through native river channels with large drop heights and minimize the ecological impact on the river channels.

[0005] In order to achieve the above object, the present invention is achieved in the following ways: A comprehensive construction method for a large-diameter thermal pipeline crossing a native river channel with a large drop, comprising: Step 1: excavation of river bank protection on the west side of the river; Step 2: Construction of steel sheet pile cofferdam on the west side of the river, and construction of working platform and temporary road at the same time; Step 3: Excavation of foundation pit on the west side of the river channel, supplemented by drainage measures; Step 4: Implement pipeline construction on the west side of the river; Step 5: Backfill the trench; Step 6: divert the river; Step 7: Construction of earth pile cofferdam on the east side of the river channel and foundation pit support at the same time; Step 8: Excavation of foundation pit on the east side of the river channel, supplemented by drainage measures; Step 9: Pipeline construction on the east side of the river; Step 10: Backfill the foundation pit on the east side of the river channel; Step 11: Restore the image to its original state and the job is done.

[0006] The above-mentioned comprehensive construction method for large-diameter thermal pipelines crossing large-drop native river channels adopts steel sheet pile cofferdams in step 2. At the same time, the steel sheet pile cofferdams also serve as part of the excavation trench support structure, combining the cofferdam construction with the foundation pit support construction and carrying them out together.

[0007] The above-mentioned comprehensive construction method for large-diameter thermal pipelines crossing large-drop original river channels uses the earth excavated from the slope protection on the west side of the river channel in step 1 to build the temporary construction road and construction platform in step 2, the construction platform and the return platform for transport vehicles. When building the temporary construction road, diversion pipes should be buried in the river channel to ensure normal water flow in the river channel, and diversion pipes for diverting the river channel when implementing steps 6 and 7 should be buried in advance.

[0008] In the above-mentioned comprehensive construction method for large-diameter thermal pipelines crossing a native river channel with a large drop, during the implementation of steps 7 and 8, the earth excavated from the slope protection on the east side of the river channel, the earth excavated from the foundation pit on the east side of the river channel, and the excess earth on the west bank are used for the construction of the earth cofferdam, and the earth cofferdam also serves as a construction platform on the east side of the river channel.

[0009] The above-mentioned comprehensive construction method for large-diameter thermal pipelines crossing the original river channel with a large drop adopts two different cofferdam methods, steel sheet pile cofferdam + earth cofferdam, on the west and east sides of the river channel, so as to realize the cross-utilization of excavated earth.

[0010] This method is suitable for pipeline laying construction that quickly crosses original ecological rivers with high drop, long distance, large excavation depth and complex geological conditions. Its advantages are as follows: 1. Compared with the traditional cofferdam excavation to cross the river, this comprehensive method is simple and convenient to construct, greatly simplifies the construction process, and effectively ensures the construction quality and safety.

[0011] 2. Compared with traditional cofferdam construction, the construction efficiency is improved by about 40% and the cost is saved by about 8%.

[0012] 3. Whether it is steel sheet pile cofferdam, earth cofferdam or diversion pipe, it has little impact on the natural environment and greatly protects the river ecological environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is the construction process flow chart of this method.

[0014] Figure 2 This is the plan view of the cofferdam construction in the first stage of this method.

[0015] Figure 3 This is the plan view of the second stage cofferdam construction of this method. DETAILED DESCRIPTION

[0016] The technical solutions of the embodiments of the present application will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field without creative work based on the embodiments in the embodiments of the present application are within the scope of protection requested by the present application.

[0017] like Figure 1 to Figure 3 A comprehensive construction method for a large-diameter thermal pipeline to cross a large drop primary river channel, including Phase 1: Step 1: excavation of river bank protection on the west side of the river; Step 2: Construction of steel sheet pile cofferdam on the west side of the river, and construction of working platform and temporary road at the same time; Step 3: Excavation of foundation pit on the west side of the river channel, supplemented by drainage measures; Step 4: Implement pipeline construction on the west side of the river; Step 5: Backfill the trench; Step 6: divert the river; Phase 2: Step 7: Construction of earth pile cofferdam on the east side of the river channel and foundation pit support at the same time; Step 8: Excavation of foundation pit on the east side of the river channel, supplemented by drainage measures; Step 9: Pipeline construction on the east side of the river; Step 10: Backfill the foundation pit on the east side of the river channel; Step 11: Restore the image to its original state and the job is done.

[0018] In the above-mentioned comprehensive construction method, during operation, the cofferdam of the first stage adopts a steel sheet pile cofferdam, and the steel sheet pile cofferdam can also serve as a part of the excavation trench support structure, combining the cofferdam construction with the foundation pit support construction and carrying out them together. Thereby saving construction time and reducing construction costs. In the first stage, the earthwork of the slope protection on the west side of the river channel will be excavated to build temporary construction roads and construction platforms, construction platforms and transport vehicle return platforms. When building temporary construction roads, diversion pipes need to be buried in the river channel to ensure normal water flow in the river channel. At the same time, diversion pipes for diverting the river channel during the second stage cofferdam construction are pre-buried in advance.

[0019] After the first phase of pipeline construction is completed and part of the trench is backfilled, the river diversion construction will be carried out first to ensure the normal operation of the river, and then the second phase of cofferdam construction can begin. In the second phase, the earthwork for the slope protection on the east side of the river channel, the earthwork for the foundation pit on the east side of the river channel, and the excess earthwork on the west bank will be excavated. These earthworks will be used for the second phase of earth cofferdam construction. At the same time, the earth cofferdam can also serve as a construction platform on the east side of the river channel. The use of earth cofferdams for the second phase cofferdam can effectively increase the construction speed and reduce the construction cost.

[0020] In the above construction method, two different cofferdam methods, steel sheet pile cofferdam + earth cofferdam, are used on the west and east sides of the river channel to achieve cross-utilization of excavated earth. Compared with the traditional cofferdam excavation across the river, this comprehensive method is simple and convenient to construct, greatly simplifies the construction process, and effectively ensures construction quality and safety. In addition, compared with traditional cofferdam construction, the construction efficiency is improved by about 40% and the cost is saved by about 8%. Furthermore, whether it is steel sheet pile cofferdam, earth cofferdam, or diversion pipe, it has little impact on the natural environment and greatly protects the river's ecological environment.

[0021] The above are only embodiments provided for the present application and are not intended to limit the present application. Although the present application is described in detail with reference to the embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. However, any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A comprehensive construction method for a large-diameter thermal pipeline crossing a primary river channel with a large drop, characterized by: include Step 1: excavation of river bank protection on the west side of the river; Step 2: Construction of steel sheet pile cofferdam on the west side of the river, and construction of working platform and temporary road at the same time; Step 3: Excavation of foundation pit on the west side of the river channel, supplemented by drainage measures; Step 4: Implement pipeline construction on the west side of the river; Step 5: Backfill the trench; Step 6: divert the river; Step 7: Construction of earth pile cofferdam on the east side of the river channel and foundation pit support at the same time; Step 8: Excavation of foundation pit on the east side of the river channel, supplemented by drainage measures; Step 9: Pipeline construction on the east side of the river; Step 10: Backfill the foundation pit on the east side of the river channel; Step 11: Restore the image to its original state and the job is done.

2. The comprehensive construction method for a large-diameter thermal pipeline crossing a primary river channel with a large drop according to claim 1 is characterized by: Step 2 adopts steel sheet pile cofferdam, which also serves as a part of the excavation trench support structure, combining the cofferdam construction with the foundation pit support construction and carrying them out together.

3. The comprehensive construction method for a large-diameter thermal pipeline crossing a primary river channel with a large drop according to claim 1 is characterized by: The earth excavated from the slope protection on the west side of the river channel in step 1 is used to build the temporary construction road and construction platform in step 2, the construction platform and the return platform for transport vehicles. When building the temporary construction road, diversion pipes should be buried in the river channel to ensure normal water flow in the river channel. At the same time, diversion pipes for diverting the river channel when implementing steps 6 and 7 should be buried in advance.

4. The comprehensive construction method for a large-diameter thermal pipeline crossing a primary river channel with a large drop according to claim 1 is characterized by: During the implementation of steps 7 and 8, the earth excavated from the slope protection on the east side of the river channel, the earth excavated from the foundation pit on the east side of the river channel, and the excess earth on the west bank are used for the construction of the earth cofferdam, which also serves as a construction platform on the east side of the river channel.

5. The comprehensive construction method for a large-diameter thermal pipeline crossing a primary river channel with a large drop according to claim 1 is characterized by: On the west and east sides of the river, two different cofferdam methods, steel sheet pile cofferdam + earth cofferdam, are used to achieve cross-utilization of excavated earth.

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