阅读说明：本技术 一种开挖仓压力释放及重建的系统及使用方法 (System for pressure release and reconstruction of excavation bin and using method ) 是由 杜昌言 夏毅敏 肖雪萌 白坤 历朋林 吴玉礼 宾锡午 李海振 董冰 舒计城 娄瑞 于 2021-09-01 设计创作，主要内容包括：本发明要解决的技术问题是提供一种开挖仓压力释放及重建的系统及使用方法,通过释放和重建开挖仓泥浆压力的方式,在开挖仓内进行主驱动密封部的更换维修,保证维持盾构开挖面的稳定性,大大节省维修成本和工期,其包括前后分布的开挖仓和气泡仓,盾构机的主驱动密封部位于所述开挖仓内；还包括分管Ⅰ、分管Ⅱ、总管和气压调节系统,所述分管Ⅰ和分管Ⅱ的一端分别对应接通所述开挖仓和气泡仓的上部,所述分管Ⅰ和分管Ⅱ的另一端连通在所述总管上,所述分管Ⅰ、分管Ⅱ和总管的管道上分别对应设置有阀门Ⅰ、阀门Ⅱ和总阀门,所述气压调节系统的进气口连通所述气泡仓的侧壁上部。(The invention provides a system for releasing and rebuilding the pressure of an excavation chamber and a using method thereof, wherein the main driving sealing part is replaced and maintained in the excavation chamber in a manner of releasing and rebuilding the slurry pressure of the excavation chamber, so as to ensure the stability of the excavation surface of a shield, greatly save the maintenance cost and the construction period, the system comprises the excavation chamber and a bubble chamber which are distributed in the front and back, and the main driving sealing part of the shield machine is positioned in the excavation chamber; still including being in charge of I, being in charge of II, house steward and air pressure governing system, the one end that is in charge of I and is in charge of II corresponds the switch-on respectively the upper portion in excavation storehouse and bubble storehouse, the other end intercommunication that is in charge of I and is in charge of II is in on the house steward, correspond respectively on the pipeline of being in charge of I, being in charge of II and house steward and be provided with valve I, valve II and total valve, air pressure governing system's air inlet intercommunication the lateral wall upper portion in bubble storehouse.)

1. A pressure release and reconstruction system for an excavation cabin comprises the excavation cabin and a bubble cabin which are distributed in the front and the back, wherein a main driving sealing part of a shield machine is positioned in the excavation cabin;

the device is characterized by further comprising a branch pipe I, a branch pipe II, a main pipe and a pressure adjusting system, wherein one end of the branch pipe I and one end of the branch pipe II are correspondingly communicated with the upper parts of the excavation bin and the bubble bin respectively, the other ends of the branch pipe I and the branch pipe II are communicated with the main pipe, a valve I, a valve II and a main valve are correspondingly arranged on pipelines of the branch pipe I, the branch pipe II and the main pipe respectively, and an air inlet of the pressure adjusting system is communicated with the upper part of the side wall of the bubble bin;

the slurry inlet is formed in the side wall of the upper portion of the excavation bin, the bottom of the excavation bin is communicated with the bottom of the bubble bin, and the slurry discharge port is formed in the side wall of the bottom of the bubble bin.

2. The pressure release and reconstruction system for the excavation cabin according to claim 1, wherein a maintenance manhole I is arranged at the top of the side wall of the bubble cabin, and a maintenance manhole II corresponding to the maintenance manhole I is arranged at the top of the side wall of the excavation cabin.

3. The excavation pressure release and reconstruction system of claim 2, wherein a connecting ladder is provided between the inspection manhole i and the inspection manhole ii.

4. Use of the system of claim 1 for pressure relief and reconstruction of a excavation comprising the steps of,

step 1, in an initial state, a valve I, a valve II and a main valve are in a closed state, an excavation bin is filled with slurry, the lower part of a bubble bin is filled with slurry, and the upper part of the bubble bin is filled with gas;

step 2, keeping the main valve in a closed state, opening the valve I and the valve II to enable the branch pipe I to be communicated with the branch pipe II, enabling gas on the upper portion of the bubble cabin to enter the upper portion of the excavation cabin through the branch pipe II and the branch pipe I, enabling the slurry liquid level in the bubble cabin to gradually rise, and enabling the slurry liquid level in the excavation cabin to gradually fall until the slurry liquid levels in the excavation cabin and the bubble cabin are approximately equal;

step 3, continuously keeping the main valve in a closed state, keeping the valve I and the valve II in an open state, opening the slurry discharge port, and slowly descending the slurry liquid levels in the bubble bin and the excavation bin simultaneously until the slurry liquid level in the excavation bin is reduced below the main driving sealing part, and then closing the slurry discharge port; the air pressure of the bubble bin and the air pressure of the excavation bin are kept stable through an air pressure adjusting system, the pressure of the excavation bin is released at the moment, and maintenance personnel enter the excavation bin to maintain and replace the main driving sealing part;

and 4, after the main driving sealing part is replaced, opening the slurry inlet, the slurry outlet, the valve I and the main valve, closing the valve II, controlling the slurry inlet flow of the slurry inlet to be larger than the slurry outlet flow of the slurry outlet, adjusting the air pressure at the upper part of the bubble bin through an air pressure adjusting system, gradually increasing the slurry liquid level in the excavation bin to be higher than the slurry liquid level in the bubble bin along with the slow rising of the slurry liquid levels in the bubble bin and the excavation bin, reestablishing the slurry liquid level difference until slurry overflows from the tail end of the main pipe communicated with the atmospheric pressure, namely proving that the excavation bin is filled with slurry, and completing the pressure reconstruction of the excavation bin.

5. The use method for releasing and rebuilding the pressure of the excavation cabin according to claim 4, wherein in the step 2, during the rise of the slurry liquid level in the bubble cabin, the air pressure in the bubble cabin is controlled by the air pressure adjusting system to assist in slowly raising the slurry liquid level height in the bubble cabin, after the liquid level of the bubble cabin rises for every 1m, the valve II is closed, the liquid level of the bubble cabin is observed for 30min, and then the valve II is continuously opened.

6. The use method for releasing and rebuilding the pressure of the excavation bin as claimed in claim 4, wherein in step 3, when the slurry level in the excavation bin is lowered to 1/3 of the excavation bin 2, the slurry discharge port is closed, the pressure change condition of the bubble bin is observed, if no obvious change occurs within 2h, the slurry discharge port is opened, the slurry level is further lowered to a position below 1/2 of the excavation bin, the slurry discharge port is closed, the pressure change condition of the bubble bin is continuously observed, and if no obvious change occurs within 2h, the slurry discharge port is opened until the slurry level in the excavation bin is lowered to a position 1-2m lower than the lower end of the main driving sealing part.

Technical Field

The invention relates to a shield construction method, in particular to a pressure release and reconstruction system for an excavation cabin and a using method.

Background

The shield equipment is the key for success and failure of the project of the ultra-large diameter shield tunnel, and the ultra-large diameter shield tunnel inevitably encounters a plurality of soil layers in the tunneling process due to the cross section size and the structure top earthing requirement, so that the shield equipment needs higher reliability and technical advancement to meet the complex environments such as hydrology, geology and buildings along the line which may appear at the site of the tunnel. The main driving sealing part is the key for ensuring the normal work of the main driving sealing part, and the abrasion and the scrapping of the driving part in the main driving are accelerated when the main driving sealing system breaks down or fails prematurely.

Particularly, for a common slurry shield machine, a front end working part of the slurry shield machine sequentially comprises a rotary cutter head, an excavation bin and a bubble bin from front to back, the excavation bin is filled with slurry with certain pressure to act on a stable excavation surface supported by the rotary cutter head, a main driving sealing part is just positioned in the excavation bin, and the periphery of the main driving sealing part is filled with the slurry. The condition that main drive sealing part became invalid is less common in current shield tunnel work progress, because the stability of excavation face is difficult to control in only case, the mode of changing sealed the adoption for digging the shaft again and hanging out the shield structure machine maintenance, and this mode cost is huge, and is consuming time long, hangs out the back with the shield structure machine simultaneously, has very big risk to the stability of shield structure excavation face.

Disclosure of Invention

The invention provides a system for releasing and rebuilding the pressure of an excavation chamber and a using method thereof, which are used for replacing and maintaining a main driving sealing part in the excavation chamber in a mode of releasing and rebuilding the slurry pressure of the excavation chamber, thereby ensuring the stability of the shield excavation surface and greatly saving the maintenance cost and the construction period.

The invention is realized by the following technical scheme:

a pressure release and reconstruction system for an excavation cabin comprises the excavation cabin and a bubble cabin which are distributed in the front and the back, wherein a main driving sealing part of a shield machine is positioned in the excavation cabin; the device comprises an excavation bin, a main pipe, a gas pressure adjusting system, a gas inlet, a gas outlet, a gas inlet and a gas outlet, and is characterized by further comprising a branch pipe I, a branch pipe II, a main pipe and a gas pressure adjusting system, wherein one end of the branch pipe I and one end of the branch pipe II are correspondingly communicated with the upper parts of the excavation bin and the gas bubble bin respectively, the other ends of the branch pipe I and the branch pipe II are communicated with the main pipe, valves I, II and a main valve are correspondingly arranged on pipelines of the branch pipe I, the branch pipe II and the main pipe respectively, and the gas inlet of the gas pressure adjusting system is communicated with the upper parts of the side walls of the gas bubble bin;

the slurry inlet is formed in the side wall of the upper portion of the excavation bin, the bottom of the excavation bin is communicated with the bottom of the bubble bin, and the slurry discharge port is formed in the side wall of the bottom of the bubble bin.

Further, the lateral wall top in bubble storehouse is equipped with maintenance manhole I, the lateral wall top in excavation storehouse be equipped with maintenance manhole II that maintenance manhole I is corresponding.

Furthermore, a connecting ladder way is arranged between the inspection manhole I and the inspection manhole II.

The use method for releasing and rebuilding the pressure of the excavation cabin by adopting the system comprises the following steps,

step 1, in an initial state, a valve I, a valve II and a main valve are in a closed state, an excavation bin is filled with slurry, the lower part of a bubble bin is filled with slurry, and the upper part of the bubble bin is filled with gas;

step 2, keeping the main valve in a closed state, opening the valve I and the valve II to enable the branch pipe I to be communicated with the branch pipe II, enabling gas on the upper portion of the bubble cabin to enter the upper portion of the excavation cabin through the branch pipe II and the branch pipe I, enabling the slurry liquid level in the bubble cabin to gradually rise, and enabling the slurry liquid level in the excavation cabin to gradually fall until the slurry liquid levels in the excavation cabin and the bubble cabin are approximately equal;

step 3, continuously keeping the main valve in a closed state, keeping the valve I and the valve II in an open state, opening the slurry discharge port, and slowly descending the slurry liquid levels in the bubble bin and the excavation bin simultaneously until the slurry liquid level in the excavation bin is reduced below the main driving sealing part, and then closing the slurry discharge port; the air pressure of the bubble bin and the air pressure of the excavation bin are kept stable through an air pressure adjusting system, the pressure of the excavation bin is released at the moment, and maintenance personnel enter the excavation bin to maintain and replace the main driving sealing part;

and 4, after the main driving sealing part is replaced, opening the slurry inlet, the slurry outlet, the valve I and the main valve, closing the valve II, controlling the slurry inlet flow of the slurry inlet to be larger than the slurry outlet flow of the slurry outlet, adjusting the air pressure at the upper part of the bubble bin through an air pressure adjusting system, gradually increasing the slurry liquid level in the excavation bin to be higher than the slurry liquid level in the bubble bin along with the slow rising of the slurry liquid levels in the bubble bin and the excavation bin, reestablishing the slurry liquid level difference until slurry overflows from the tail end of the main pipe communicated with the atmospheric pressure, namely proving that the excavation bin is filled with slurry, and completing the pressure reconstruction of the excavation bin.

Further, in the step 2, in the process of rising the liquid level of the slurry in the bubble bin, the air pressure in the bubble bin is controlled by the air pressure adjusting system to assist in slowly rising the height of the liquid level of the slurry in the bubble bin, after the liquid level of the bubble bin rises by 1m, the valve II is closed, the liquid level of the bubble bin is observed for 30min, and then the valve II is continuously opened.

Further, in step 3, when the slurry liquid level in the excavation bin is lowered to 1/3 of the excavation bin 2, closing the slurry discharge port, observing the pressure change condition of the bubble bin, if no obvious change exists within 2h, opening the slurry discharge port, enabling the slurry liquid level to be lowered below 1/2 of the excavation bin continuously, closing the slurry discharge port, observing the pressure change condition of the bubble bin continuously, and if no obvious change exists within 2h, opening the slurry discharge port until the slurry liquid level in the excavation bin is lowered to a position 1-2m lower than the lower end of the main driving sealing part.

Compared with the prior art, the invention has the following beneficial effects:

1. according to the system for releasing and rebuilding the pressure of the excavation bin, the liquid levels of the slurry in the excavation bin and the slurry in the bubble bin are close or even equal, then the liquid levels in the excavation bin and the bubble bin are synchronously lowered through the slurry discharge port until the liquid level of the slurry in the excavation bin is lowered below the main driving sealing part, and then maintenance personnel enter from the upper part of the excavation bin to maintain and replace the main driving sealing part; after maintenance is finished, opening a slurry inlet and a slurry outlet, controlling the slurry inlet flow of the slurry inlet to be larger than the slurry outlet flow of the slurry outlet, and adjusting the air pressure at the upper part of the bubble chamber through an air pressure adjusting system to fully fill slurry in the excavation chamber to finish pressure reconstruction of the excavation chamber;

the invention avoids the previous maintenance mode of hanging the shield machine out by drilling a vertical shaft in front after the shield machine is stopped, does not need to take out the shield machine, and replaces the main driving sealing part on the premise of maintaining the stability of the shield excavation surface, thereby greatly reducing the manpower, material resources and financial resources and shortening the construction period;

2. the top of the side wall is provided with an inspection manhole I, the top of the side wall of the excavation bin is provided with an inspection manhole II, a connecting ladder is arranged between the inspection manhole I and the inspection manhole II, and after the liquid level of slurry in the excavation bin drops, the slurry directly enters the excavation bin through two inspection persons, so that the working efficiency is improved, and the safety of maintenance personnel is ensured;

3. in the descending process of the slurry liquid level in the blocking excavation bin, a discontinuous descending mode is adopted, the phenomenon that the slurry in the excavation bin descends too fast to cause instability of external pressure is avoided, and the safety in the operation process is improved.

Drawings

FIG. 1 is a schematic structural diagram of a pressure release and reconstruction system for an excavation cabin according to the present invention;

FIG. 2 is a schematic diagram of the pressure release and reconstruction system for the excavation of the excavation in step 2;

FIG. 3 is a schematic diagram of the pressure release and reconstruction system for the excavation of the excavation chamber of the present invention at step 3;

in the figure: 1. rotatory blade disc, 2, bubble storehouse, 3, excavation storehouse, 4, divide pipe I, 5, divide pipe II, 6, house steward, 7, atmospheric pressure governing system, 8, valve I, 9, valve II, 10, total valve, 11, the thick liquid mouth of advancing, 12, arrange the thick liquid mouth, 13, maintenance manhole I, 14, maintenance manhole II.

Detailed Description

The technical solutions in the embodiments of the present application will be described clearly and completely with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present application without making any creative effort, shall fall within the protection scope of the present application.

In the description of the present invention, it is to be understood that the terms "front", "back", "upper", "lower", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are only for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention.

By taking the main drive sealing part maintenance replacement for the muddy water type shield tunneling machine as an example, the embodiment discloses a system for pressure release and reconstruction of an excavation cabin, which comprises an excavation cabin, a bubble cabin 2, a branch pipe I4, a branch pipe II 5, a main pipe 6 and a pressure adjusting system 7 which are distributed in front and back as shown in fig. 1. In the structure of the slurry shield machine, the front working part of the slurry shield machine is sequentially provided with a rotary cutter head 1, an excavation bin 3 and a bubble bin 2 from front to back, and the excavation bin and the bubble bin 2 are all bin bodies which can be closed. The excavation cabin is filled with slurry with a certain pressure to counteract the pressure on the rotary cutter head 1 during excavation, so that the pressure acts on the rotary cutter head 1 to support and stabilize an excavation surface, the main driving sealing part is just positioned in the excavation cabin, the periphery of the main driving sealing part is filled with the slurry, the upper part in the foam cabin is gas, and the lower part is the slurry.

Divide pipe I4, divide pipe II 5, house steward 6 and air pressure governing system 7 all are located the shield structure built-in, divide pipe I4 and divide pipe II 5 to be the horizontal distribution design, divide the front end of pipe I4 and divide pipe II 5 to correspond the position that the upper portion of switch-on excavation storehouse and bubble storehouse 2 is close to the top respectively, divide the right-hand member of pipe I4 and divide pipe II 5 then to connect on house steward 6 through the three-way pipe, house steward 6's the other end switch-on atmosphere. And the pipelines of the branch pipe I4, the branch pipe II 5 and the main pipe 6 are respectively and correspondingly provided with a valve I8, a valve II 9 and a main valve 10.

The air inlet of air pressure regulating system passes through the position that the lateral wall upper portion of admission line intercommunication bubble storehouse is close to the top, in this embodiment, air pressure regulating system chooses for use in the shield field commonly used samson pressure automatic regulating system, samson pressure automatic regulating system can keep the bubble storehouse internal gas pressure value to be close the numerical value of settlement, when atmospheric pressure surpassed the setting value, air pressure regulating system extraction gas reduces atmospheric pressure, when atmospheric pressure is less than the setting value, air pressure regulating system input gas carries out the pressure boost, thereby upper portion atmospheric pressure numerical value in the control bubble storehouse through air pressure regulating system. The specific working principle of the automatic samson pressure regulating system is that in the control operation, an actuating mechanism is controlled by a pressure signal of a valve positioner. The pressure transmitter converts the actual pressure at the upper part in the bubble chamber into a standard air pressure signal and sends the standard air pressure signal to the regulator. The regulator compares the measured value sent by the pressure transmitter with a set value to obtain a deviation, and outputs a corresponding control signal to the positioner after operation according to the PI control rule according to the deviation size and the variation trend, thereby determining whether to intake air or exhaust air to the bubble chamber.

The position that is close to the top at the upper portion lateral wall in excavation storehouse is equipped with into thick liquid mouth 11 and is used for communicateing into thick liquid pipeline, and the bottom in excavation storehouse is link up with the bottom in bubble storehouse 2, is equipped with row thick liquid mouth 12 and is used for communicateing row thick liquid pipeline in the position that the bottom lateral wall in bubble storehouse 2 is close to the bottom. Be equipped with at the rear side wall top in bubble chamber 2 and overhaul manhole I13, be equipped with at the rear side wall top in excavation storehouse and overhaul manhole II 14, overhaul manhole II 14 and overhaul manhole I13 and be in same level, and install between and connect the ladder way. Under normal conditions, overhaul manhole I13 and overhaul manhole II 14 and all seal through the door body and close, when needs maintain, can be through opening overhaul manhole II 14 and overhaul manhole I13, make the maintainer pass in proper order and overhaul manhole I13 and overhaul manhole II 14 and get into in the excavation storehouse.

The working principle of the invention is that for the slurry shield machine, in the tunneling process of the slurry shield machine, a main driving sealing part fails, the slurry in the excavation chamber needs to be replaced by a main driving part, the liquid level of the slurry in the excavation chamber needs to be lowered, the excavation chamber is communicated with the bubble chamber 2, the bubble chamber 2 is provided with a set of air pressure adjusting system 7, the air pressure adjusting system 7 is utilized, and a branch pipe I4, a branch pipe II 5 and a main pipe 6 which are connected with the atmospheric pressure, the excavation chamber and the bubble chamber 2 are additionally arranged to adjust the pressure of the excavation chamber and the bubble chamber 2, so that the rising and the falling of the liquid level are completed, and the pressure releasing and the rebuilding process of the excavation chamber are completed at the same time. The use method for releasing and rebuilding the pressure of the excavation bin by adopting the system provided by the invention comprises the following specific steps:

step 1, in an initial state, a valve I8, a valve II 9 and a main valve 10 are in a closed state, an excavation bin is filled with slurry, the lower part of a bubble bin 2 is filled with slurry, the upper part of the bubble bin is filled with gas, and an air pressure adjusting system 7 detects that the gas pressure at the upper part of the bubble bin 2 is P₀(ii) a In order to maintain the liquid level difference between the bubble chamber 2 and the excavation chamber, the gas pressure at the upper part of the bubble chamber 2 is always larger than the external atmospheric pressure and is different between 6 and 9 bar;

step 2, keeping the main valve 10 in a closed state, opening a valve I8 and a valve II 9 to enable a branch pipe I4 to be communicated with a branch pipe II 5, enabling gas on the upper portion of the bubble chamber 2 to enter the upper portion of the excavation chamber through the branch pipe II 5 and the branch pipe I4, enabling the slurry liquid level in the bubble chamber 2 to gradually rise, and enabling the slurry liquid level in the excavation chamber to gradually fall;

as shown in fig. 2, in the process of rising the slurry liquid level in the bubble chamber 2, the air pressure in the bubble chamber 2 is controlled by the air pressure adjusting system 7 to assist in slowly rising the slurry liquid level height in the bubble chamber 2, when the liquid level of the bubble chamber 2 rises by 1m, the valve ii 9 is closed, the liquid level and the pressure of the bubble chamber 2 are observed for 30min, and after no sudden change is determined, the valve ii 9 is continuously opened, so that the operation steps are designed, and the instability caused by too fast slurry liquid level change is avoided until the slurry liquid levels in the excavation chamber and the bubble chamber 2 are approximately equal;

step 3, as shown in figure 3, continuously keeping the main valve 10 in a closed state, keeping the valve I8 and the valve II 9 in an open state, opening the slurry discharge port 12, slowly lowering the slurry levels in the bubble bin 2 and the excavation bin simultaneously, when the slurry level in the excavation bin is reduced to the position which is far away from the top 1/3 of the excavation bin, the slurry discharge port 12 is closed, the pressure change condition of the bubble bin 2 is observed, if no obvious change exists within 2h, the slurry discharge port 12 is continuously opened, the slurry liquid level is continuously reduced to below 1/2 of the excavation bin, the slurry discharge port 12 is closed, the pressure change condition of the bubble bin 2 is continuously observed, if no obvious change exists within 2h, the slurry discharge port 12 is opened until the liquid level of the excavation bin is reduced to a position 1-2m lower than the lower end of the main driving sealing part, the slurry discharge port 12 is closed, the main driving sealing part is exposed in the excavation bin at the moment, and slurry does not need to be discharged;

the air pressure of the bubble bin 2 and the air pressure of the excavation bin are kept stable through the air pressure adjusting system 7, and the air pressure adjusting system is suitable for entering of maintenance personnel, at the moment, the pressure release of the excavation bin is completed, the maintenance personnel enter the excavation bin through the maintenance manhole I13 and the maintenance manhole II 14, and the maintenance and the replacement of the main driving sealing part are carried out;

step 4, after the replacement of the main driving sealing part is completed, the maintenance personnel returns to the original path, the slurry inlet 11, the slurry outlet 12, the valve I8 and the main valve 10 are opened, the valve II 9 is closed, the slurry inlet flow of the slurry inlet 11 is controlled to be larger than the slurry outlet flow of the slurry outlet 12, and the air pressure adjusting system 7 is used for adjusting and increasing the size of the bubble bin 2The air pressure at the upper part rises slowly along with the slurry liquid level in the bubble bin 2 and the excavation bin, because the valve II 9 is in a closed state, the gas in the bubble bin 2 cannot enter the excavation bin, the gas in the excavation bin rises along with the slurry liquid level and is directly discharged from the main pipe 6, the slurry liquid level injected into the excavation bin along with the slurry is gradually higher than the slurry liquid level in the bubble bin 2, the slurry liquid level difference is reestablished until the slurry overflows at the tail end of the main pipe 6 communicated with the atmospheric pressure, namely, the excavation bin is proved to be filled with the slurry, and in the process, the air pressure at the upper part of the bubble bin 2 is gradually adjusted to reach P through the air pressure adjusting system 7₀；

And finally, completing pressure reconstruction of the excavation cabin.

The invention avoids the traditional maintenance mode of hanging the shield machine out by drilling a vertical shaft in front after the shield machine is stopped, does not need to take out the shield machine, and replaces the main driving sealing part on the premise of maintaining the stability of the shield excavation surface, thereby greatly reducing the manpower, material resources and financial resources and shortening the construction period.