Method for improving anti-seepage performance of side wall of subway station by reserving pouring pipe hole

Abstract

The invention relates to the field of subway station buildings, in particular to a method for improving the anti-seepage performance of a side wall of a subway station by reserving a pouring pipe hole, and the method comprises the following steps: S1, excavating a deep pit of a continuous wall; s2, deep pit tamping; s3, continuous wall pouring; s4, constructing a cement mortar leveling layer; s5, waterproof layer construction; s6, side wall construction; s7, a formwork is laid, specifically, a main body structure concrete pouring formwork is installed in the side wall deep pit; and S8, concrete pouring is conducted, after multiple layers of concrete are solidified, a waterproof reinforced concrete side wall is formed, a middle iron plate is pre-buried in the lowermost portion of the to-be-poured part, and a pouring hole is reserved in the middle iron plate. The middle iron plate is pre-buried at the lowermost part of the to-be-poured part before the upper concrete is poured, the pouring hole is reserved in the middle iron plate, and the concrete can flow to the position below the middle iron plate from the pouring hole to fill the gap, so that the pouring gap is reduced, and the anti-seepage performance of the underground diaphragm wall is improved.

Description

Technical Field

[0001] The invention relates to the field of subway station construction, and in particular to a method for improving the anti-seepage performance of a subway station side wall by pre-reserving a casting pipe hole. Background Art

[0002] During the construction and operation of subway stations, due to the complex environment and many weak points in anti-seepage, water leakage is very common in the top plate, side wall, bottom plate and other locations. After the subway station is built, leakage control is difficult, costly and ineffective. In addition, the proportion of re-leakage after control is large, which affects the operation and maintenance of the subway. In severe cases, it even affects the durability of the main structure and causes engineering risks. Therefore, it is necessary to improve the anti-seepage performance of subway stations.

[0003] The waterproofing of the main structure of the subway station mainly relies on the waterproofing performance of the structure itself, and consists of three parts: the retaining structure, the additional flexible waterproof layer, and the self-waterproofing of the main structure concrete. The first is the waterproofing of the station foundation pit retaining structure. When the ground-connected wall is used as the supporting structure, the waterproofing performance of the ground-connected wall itself is the main factor. The waterproofing between the retaining structure and the main structure mainly relies on the additional fully-covered flexible waterproof layer material. The waterproofing of the main structure concrete mainly relies on the waterproofing performance of the concrete material itself after the main structure is built.

[0004] During the pouring of concrete for the side walls of a top-down subway station, certain gaps are created due to concrete shrinkage. To prevent groundwater from seeping in along the gaps and improve the integrity of the side walls, some concrete is often poured into the gaps. However, in a top-down subway station, it is difficult to fill in concrete due to the obstruction of the upper concrete that has been poured. Therefore, how to reduce the gap created when the upper and lower concrete solidify is a technical problem that needs to be urgently solved by those skilled in the art. Summary of the invention

[0005] The technical problem to be solved by the present invention is: in order to solve the problem of large gaps generated when the upper concrete and the lower concrete solidify, the present invention provides a method for improving the anti-seepage performance of the side wall of a subway station by reserving casting pipe holes to solve the above problem. The technical solution adopted by the present invention to solve the technical problem is: a method for improving the anti-seepage performance of the side wall of a subway station by reserving a casting pipe hole, comprising the following steps: S1, excavation of a continuous wall deep pit, surveying the site and removing ground obstacles, and then excavating the ground to a predetermined depth to form a continuous wall deep pit; S2, tamping the deep pit, using a tamping machine to tamp the excavated ground and the continuous wall deep pit; S3, continuous wall casting, laying a template in the continuous wall deep pit, then hoisting a steel cage and pouring concrete, and forming an underground continuous wall after the concrete solidifies; S4, cement mortar leveling layer construction, applying cement mortar on the outer side of the underground continuous wall for leveling, and forming a cement mortar leveling layer after the cement mortar solidifies; S5, waterproof layer construction, laying waterproof membrane outside the underground continuous wall to form a membrane waterproof layer; S6, side wall construction, digging a side wall pit on the ground on one side of the waterproof membrane and hoisting a steel cage into the side wall pit; S7, formwork laying, installing the main structure concrete casting formwork in the side wall pit; S8, concrete pouring, pouring concrete into the main structure concrete casting formwork in multiple layers in sequence, and forming a waterproof reinforced concrete side wall after the multiple layers of concrete solidify, with construction joints formed between each layer of concrete. Before pouring the upper concrete, a middle iron plate is pre-buried at the bottom of the part to be poured, and pouring holes are reserved on the middle iron plate, so that concrete can flow from the pouring holes to the bottom of the middle iron plate. Preferably, in S2, the top side walls of the continuous wall pit are widened to both sides and concrete is poured, and a top protective wall is formed after the concrete solidifies.

[0006] Preferably, in S7, the main structure concrete casting template is provided with a plurality of intermediate vibration ports during the installation process.

[0007] Preferably, in S8, a casting pipe is fixed in the casting hole, and the height of the casting pipe is higher than the upper concrete.

[0008] Preferably, in S8, after pouring concrete into the main structure concrete pouring formwork, an inserted vibrator is used to compact the concrete from the middle vibrating port.

[0009] Preferably, in S8, each layer of concrete should be poured and compacted before the previous layer of concrete begins to set, so as to prevent damage to the previously poured concrete.

[0010] Preferably, in S4, before the cement mortar leveling layer is constructed, the construction joints of the underground continuous wall are roughened first, and then mud is applied to the construction joints. After the mud solidifies, cement mortar is applied for leveling.

[0011] The beneficial effect of the present invention is that multiple layers of concrete are poured into the concrete pouring template of the main structure in sequence, and each layer of concrete should be poured before the previous layer of concrete is initially set. Before pouring the upper concrete, an intermediate iron plate is pre-buried at the bottom of the part to be poured, and a pouring hole is reserved on the intermediate iron plate. A pouring pipe is fixed in the pouring hole. The height of the pouring pipe is higher than the upper concrete. After the concrete enters the pouring pipe, it can flow from the pouring hole to the bottom of the intermediate iron plate. When the upper concrete and the lower concrete are solidified, a certain gap will be generated due to the shrinkage of the concrete. In order to prevent groundwater from flowing along the gap, In order to prevent seepage, it is necessary to fill the gap with concrete to seal it. In the reverse construction subway station, it is difficult to fill in concrete due to the obstruction of the upper poured concrete. Therefore, the present invention adopts a method of pre-embedding the middle iron plate and the pouring pipe before the upper concrete is poured. After the upper concrete and the lower concrete are poured and shrink to a certain extent, concrete is poured into the pouring pipe to make the concrete flow from the pouring hole of the middle iron plate into the gap between the upper concrete and the lower concrete to fill the gap, thereby reducing the pouring gap and effectively improving the anti-seepage performance of the underground continuous wall. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the implementation methods or the description of the prior art. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0013] Figure 1 It is a structural schematic diagram of an optimal embodiment of the present invention for improving the side wall of a subway station by arranging guide plates on the side wall; Figure 2 It is a structural schematic diagram of the intermediate iron plate of the present invention.

[0014] Figure numerals: 1. underground continuous wall; 2. upper concrete; 3. middle iron plate; 4. casting hole; 5. cement mortar leveling layer; 6. waterproof reinforced concrete side wall; 7. casting pipe; 8. rolled waterproof layer. DETAILED DESCRIPTION

[0015] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0016] The following first describes the concepts involved in the present application in conjunction with the accompanying drawings. It should be noted that the following description of each concept is only to make the content of the present application easier to understand, and does not limit the scope of protection of the present application; at the same time, the embodiments and features in the embodiments of the present application can be combined with each other in the absence of conflict. The present application will be described in detail with reference to the accompanying drawings and in conjunction with the embodiments.

[0017] like Figure 1 and Figure 2 As shown, the present invention provides an embodiment of a method for improving the anti-seepage performance of the side wall of a subway station by reserving a casting pipe hole, comprising the following steps: S1. Excavation of continuous wall deep pit: survey the site and remove ground obstacles, then excavate the ground to the predetermined depth to form a continuous wall deep pit.

[0018] S2. Ramming of the deep pit: Use a rammer to ram the ground and the continuous wall deep pit after excavation, widen the top side walls of the continuous wall deep pit to both sides and pour concrete, and form a top protective wall after the concrete solidifies. The top protective wall can protect the top of the excavated continuous wall deep pit to prevent debris from falling when laying the formwork in the continuous wall deep pit, which is beneficial to maintaining the stability of the side walls of the continuous wall deep pit.

[0019] S3, continuous wall casting, laying formwork in the continuous wall deep pit, then hoisting steel cage and pouring concrete, after the concrete solidifies, the underground continuous wall 1 is formed.

[0020] S4, construction of cement mortar leveling layer 5. Before the construction of cement mortar leveling layer 5, the construction joint of the underground continuous wall 1 is roughened first, and then mud is applied to the construction joint position. The roughened construction joint can be tightly bonded with the mud and cement mortar, thereby improving the waterproof performance of the construction joint position. After the mud solidifies, cement mortar is applied for leveling. Cement mortar is applied to the outer side of the underground continuous wall 1 for leveling. After the cement mortar solidifies, a cement mortar leveling layer 5 is formed. By arranging the cement mortar leveling layer 5 on the outer side of the underground continuous wall 1, the waterproof surface of the underground continuous wall 1 is kept flat, and liquid is prevented from being retained on the surface of the underground continuous wall 1 during leakage, thereby keeping the underground continuous wall 1 dry. At the same time, the cement mortar leveling layer 5 can also prevent the rough surface of the underground continuous wall 1 from scratching the subsequently laid roll waterproof layer 8, and is beneficial to reducing the gap between materials and preventing the roll waterproof layer 8 from falling off.

[0021] S5. Waterproof layer construction. Waterproof membrane is laid outside the underground continuous wall 1 to form a membrane waterproof layer 8. The membrane waterproof layer 8 adopts self-adhesive waterproof membrane. The self-adhesive waterproof membrane can be stably adhered to one side of the underground continuous wall 1 and fit tightly with the cement mortar leveling layer 5 to improve the waterproof performance of the underground continuous wall 1. That is, the membrane waterproof layer 8 prevents liquid from directly entering the subway station during large-scale leakage. When the waterproof membrane is damaged, the liquid is blocked again by the subsequent waterproof reinforced concrete side wall 6 after passing through the waterproof membrane to avoid large-scale diffusion of the leaked liquid.

[0022] S6. For side wall construction, a deep pit for the side wall is excavated on the ground on one side of the waterproof membrane and a steel cage is hoisted into the deep pit for the side wall.

[0023] S7. Formwork laying: install the main structure concrete pouring formwork in the deep pit of the side wall. The main structure concrete pouring formwork is equipped with multiple intermediate vibration ports during the installation process.

[0024] S8. Concrete pouring: pour concrete into the concrete pouring formwork of the main structure in multiple layers in sequence. Each layer of concrete should be poured before the previous layer of concrete begins to set, and use an inserted vibrator to tamp the concrete from the middle vibration port to prevent damage to the first poured concrete. After the multiple layers of concrete solidify, a waterproof reinforced concrete side wall 6 is formed, and a construction joint is formed between each layer of concrete.

[0025] Before pouring the upper concrete 2, an intermediate iron plate 3 is pre-buried at the bottom of the part to be poured. A pouring hole 4 is reserved on the intermediate iron plate 3. A pouring pipe 7 is fixed in the pouring hole 4. The height of the pouring pipe 7 is higher than the upper concrete 2. After the concrete enters the pouring pipe 7, it can flow from the pouring hole 4 to the bottom of the intermediate iron plate 3. When the upper concrete 2 and the lower concrete solidify, a certain gap will be generated due to the shrinkage of the concrete. In order to prevent groundwater from infiltrating along the gap, it is necessary to fill the gap with concrete for sealing. In a subway station, it is difficult to fill in concrete due to the obstruction of the poured concrete on the upper part. Therefore, the present invention adopts a method of pre-embedding the middle iron plate 3 and the pouring pipe 7 before pouring the upper concrete 2. After the pouring of the upper concrete 2 and the lower concrete is completed and a certain shrinkage occurs, concrete is poured into the pouring pipe 7, so that the concrete flows from the pouring hole 4 of the middle iron plate 3 into the gap between the upper concrete 2 and the lower concrete, filling the gap, thereby reducing the pouring gap and effectively improving the anti-seepage performance of the underground continuous wall 1.

[0026] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and its core ideas of this application. The above are only preferred implementation methods of this application. It should be pointed out that due to the limitations of textual expression and the objective existence of infinite specific structures, ordinary technicians in this technical field can make several improvements, modifications or changes without departing from the principles of this application, and can also combine the above technical features in an appropriate manner; these improvements, modifications, changes or combinations, or the direct application of the concept and technical solution of the invention to other occasions without improvement, should be regarded as the scope of protection of this application.

Claims

1. A method for improving the anti-seepage performance of the side wall of a subway station by reserving pouring pipe holes. It is characterized in that The following steps are involved: S1. Excavation of the continuous wall pit: survey the site and remove ground obstacles, then excavate the ground to the predetermined depth to form the continuous wall pit; S2, deep pit compaction, using compactors to compact the excavated ground and the deep pit of the continuous wall; S3, continuous wall pouring, laying formwork in the continuous wall deep pit, then hoisting the steel cage and pouring concrete, and after the concrete solidifies, an underground continuous wall is formed (1); S4, constructing a cement mortar leveling layer (5), applying cement mortar on the outer side of the underground continuous wall (1) for leveling, and forming a cement mortar leveling layer (5) after the cement mortar solidifies; S5, waterproof layer construction, laying waterproofing coiled material outside the underground continuous wall (1) to form a coiled waterproof layer (8); S6, side wall construction, dig a side wall pit on the ground on one side of the waterproof membrane and hoist the steel cage into the side wall pit; S7, formwork laying, installing the main structure concrete pouring formwork in the side wall pit; S8, concrete pouring, pouring concrete into the main structure concrete pouring template in layers in sequence, forming a waterproof reinforced concrete side wall (6) after the multiple layers of concrete solidify, forming a construction joint between each layer of concrete, and before pouring the upper concrete (2), pre-embedded an intermediate iron plate (3) at the bottom of the part to be poured, and a pouring hole (4) is reserved on the intermediate iron plate (3), so that concrete can flow from the pouring hole (4) to the bottom of the intermediate iron plate (3).

2. The method for improving the anti-seepage performance of the side wall of a subway station by pre-reserving casting pipe holes as claimed in claim 1, Features: In S2, the top side walls of the continuous wall pit are widened to both sides and concrete is poured, and a top protective wall is formed after the concrete solidifies.

3. The method for improving the anti-seepage performance of the side wall of a subway station by pre-reserving casting pipe holes as claimed in claim 1, Features: In S7, the main structure concrete pouring template is provided with a plurality of intermediate vibration openings during the installation process.

4. The method for improving the anti-seepage performance of the side wall of a subway station by pre-reserving casting pipe holes as claimed in claim 1, Features: In S8, a pouring pipe (7) is fixed in the pouring hole (4), and the height of the pouring pipe (7) is higher than the upper concrete (2).

5. The method for improving the anti-seepage performance of the side wall of a subway station by pre-reserving casting pipe holes as claimed in claim 4, Features: In S8, after pouring concrete into the main structure concrete pouring formwork, an inserted vibrator is used to compact the concrete from the middle vibrating port.

6. The method for improving the anti-seepage performance of the side wall of a subway station by pre-reserving casting pipe holes as claimed in claim 5, Features: In S8, each layer of concrete shall be poured and compacted before the previous layer of concrete begins to set to prevent damage to the previously poured concrete.

7. The method for improving the anti-seepage performance of the side wall of a subway station by pre-reserving casting pipe holes as claimed in claim 1, Features: In S4, before the cement mortar leveling layer (5) is constructed, the construction joint of the underground continuous wall (1) is roughened, and then mud is applied to the construction joint. After the mud solidifies, cement mortar is applied for leveling.

Images