CN107268638A - Water rich strata Deep Foundation Pit of Metro Stations side wall waterproof construction and its construction method - Google Patents

Abstract

The invention discloses a waterproof structure for a side wall of a deep foundation pit of a subway station in a water-rich stratum. The invention also discloses a construction method for the waterproof structure of the side wall of the deep foundation pit of the subway station in the water-rich stratum. First, the design outline of the foundation pit is translated to the outside; , and then the main structure is poured, and finally the side wall is waterproofed. The waterproof structure of the side wall of the deep foundation pit of the subway station in the water-rich stratum and the construction method thereof in the present invention are applicable to the waterproof construction of the foundation pit under various geological conditions, and the waterproof effect of the deep foundation pit of the subway station under the geological conditions of the water-rich stratum is particularly obvious , avoiding the damage caused by binding steel bars and pouring concrete to the laid waterproof membrane when constructing the main structure, the invention has low construction difficulty, reduces the cumbersome adjustment of personnel, machinery and construction methods, and reduces construction costs.

Description

Waterproof structure and construction method of side wall of deep foundation pit of subway station in water-rich stratum

technical field

The invention relates to the technical field of underground engineering design and construction, in particular to a waterproof construction technology for a side wall of a deep foundation pit of a subway station in a water-rich stratum.

Background technique

For deep foundation pit projects of subway stations in water-rich strata, the groundwater depth is often shallow and the water volume is relatively abundant. Once the waterproof system of the foundation pit leaks, it will seriously affect the stability of the foundation pit and the safety of surrounding buildings. The existing deep foundation pit waterproof construction technology of subway stations is still not very mature, and there are still some problems and deficiencies in the waterproof construction technology.

The existing waterproof construction technology for the side wall of the deep foundation pit of the subway station is to first apply a 20cm thick cement mortar screed on the inner side of the underground diaphragm wall, then lay a waterproof membrane on the screed, and finally construct the main structure. However, in the construction technology of construction joints and induced joints, the waterproof membrane is often not in close contact with the concrete, resulting in the formation of air bubbles or gaps; As a result, the contact between the waterproof membrane and the concrete is not dense, resulting in the formation of air bubbles.

The existing foundation pit waterproofing technology can be applied with a certain thickness of fine stone concrete protective layer to protect the waterproofing membrane after laying the baseboard waterproofing membrane, so as to avoid damage to the waterproofing membrane during operations such as binding the baseplate to steel bars. The protective layer cannot be applied on the outside of the side wall of the pit, that is to say, the existing waterproof construction technology of the side wall of the foundation pit cannot avoid the damage to the waterproof membrane due to operations such as tying steel bars to the bottom plate when constructing the main structure.

Contents of the invention

In order to solve the above technical problems, the present invention provides a waterproof structure for the side wall of the deep foundation pit of the subway station in the water-rich stratum and its construction method, which effectively ensures the safe, fast and low-cost excavation of the deep foundation pit project of the subway station in the water-rich stratum. Effective water-stop effect can be achieved on the basis of the structure, which reduces the construction difficulty and saves the construction cost.

To achieve the above object, the present invention provides the following technical solutions:

The invention provides a water-rich stratum subway station deep foundation pit side wall waterproof structure and its construction method, which sequentially includes an enclosure structure layer, a backfill soil layer, a waterproof coiled material layer and a main structure side wall layer from outside to inside. The waterproof membrane layer is laid on the outer side of the main structure side wall layer;

The waterproof membrane of the waterproof membrane layer is a self-adhesive waterproof membrane;

The present invention also provides a construction method for the waterproof structure of the side wall of the deep foundation pit of the subway station in the water-rich stratum, and the construction steps are as follows:

Step 1, the design outline of the foundation pit is translated to the outside, and the construction groove of the side wall waterproof membrane is reserved;

Step two, construction preparation;

Step 3, building an enclosure structure, and excavating the foundation pit;

Step 4, pouring the main structure;

Step 5: After the pouring of the side wall of the main structure is completed, in the construction groove of the waterproof coiled material of the side wall, the waterproof coiled material is laid from the bottom layer of the foundation pit on the outer side of the side wall of the main structure, and soil is backfilled after the laying is completed. The backfill soil shall be compacted to complete the waterproof construction of the side walls of the main structure.

The design outline of the foundation pit in the first step is shifted outward by 80cm to 100cm.

The construction preparation in the second step includes compiling a detailed waterproof construction technical plan and making a detailed technical disclosure.

Optionally, the enclosure structure in step 3 is an underground continuous wall, and the foundation pit is excavated to the design value of the bottom of the pit to be inspected.

Optionally, carry out the waterproof construction of the bottom plate of the foundation pit before carrying out the step 4 pouring the main structure, first apply a 150cm thick C20 concrete cushion at the bottom of the foundation pit, secondly lay a waterproof membrane, and then apply a 50cm thick The C20 fine stone concrete protective layer is finally applied as the bottom plate of the foundation pit.

Optionally, the waterproof roll is a self-adhesive waterproof roll, and when the waterproof roll is laid, the overlapping width of two adjacent waterproof rolls is not less than 10 cm.

Optionally, the main structure is one layer. During the laying of the waterproof coiled material in the step five, the coiled waterproof material is directly laid on the roof of the foundation pit, and the two adjacent waterproof coiled materials The overlapping width is not less than 10cm, and then soil is taken for backfilling and the backfilling soil is compacted.

Optionally, the main structure has more than two layers, and during the laying of the waterproof coiled material in the step 5, the waterproof coiled material is laid to at least 10 cm below the upper floor of the bottom layer of the foundation pit Stop laying at any time, take soil and backfill in the side wall waterproof membrane construction groove to at least 10cm below the upper edge of the laid waterproof membrane, and tamp the backfill soil, and then place it on the outside of the main structure side wall Continue to lay the waterproof membrane at least 10cm below the upper edge of the waterproof membrane that has been laid, and the overlapping width of the waterproof membrane that has been laid is not less than 10cm, and the overlapping of two adjacent waterproof membranes The joint width is not less than 10cm, and the laying process of the waterproof coiled material in the step five is repeated until the waterproof coiled material laid on the side wall of the main structure is laid to the roof of the foundation pit.

Compared with the prior art, the present invention has achieved the following technical effects:

The waterproof structure of the side wall of the deep foundation pit of the subway station in the water-rich stratum and the construction method thereof in the present invention are suitable for the waterproof construction of the foundation pit under various geological conditions, and the waterproof effect of the deep foundation pit of the subway station under the geological conditions of the water-rich stratum is particularly obvious A distance of 80cm is reserved between the main structure of the foundation pit and the maintenance structure in the present invention, which provides space for artificially laying the self-adhesive waterproof coiled material; the present invention lays the self-adhesive anti-water coiled material on the outside of the smooth structure side wall , to avoid the technical problems of the waterproof membrane and the concrete being not densely contacted due to improper handling of the enclosure structure when the waterproof membrane is laid on the enclosure structure, and also to avoid the construction of the main structure, binding steel bars, and pouring concrete The damage caused to the laid waterproof membrane; the construction difficulty of the present invention is low, which reduces the cumbersome adjustment of personnel, machinery and construction methods, and reduces the construction cost.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required in the embodiments. Obviously, the accompanying drawings in the following description are only some of the present invention. Embodiments, for those of ordinary skill in the art, other drawings can also be obtained according to these drawings without paying creative labor.

Fig. 1 is a schematic diagram of foundation pit side wall waterproof construction of the present invention;

Fig. 2 is a flow chart of the waterproofing construction technology for foundation pits in water-rich strata according to the present invention.

Explanation of reference signs: 1. Main structure side wall; 2. Self-adhesive waterproof membrane; 3. Construction groove of side wall waterproof membrane; 4. Enclosure structure; 5. Foundation pit floor; 6. 50cm thick C20 fine stone concrete Protective layer; 7. C20 concrete cushion after 150cm; 8. Floor 2 underground; 9. Floor 1 underground; 10. Foundation pit roof; 11. 10cm below the floor 2 underground; 13. Backfilling.

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

In order to make the above objects, features and advantages of the present invention more comprehensible, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

The present invention provides a waterproof structure for the side wall of a deep foundation pit of a subway station in a water-rich stratum, including a four-layer structure, as shown in Figure 1, which is an enclosure structure 4, backfill soil 13, and self-adhesive waterproof coiled material 2 in sequence from outside to inside. and the side wall 1 of the main structure, and the waterproof membrane 2 is laid on the side wall 1 of the main structure.

The present invention also provides a construction method for the waterproof structure of the side wall of the deep foundation pit of a subway station in a water-rich stratum, as shown in Figure 1-2, and the construction steps are as follows:

Step 1, the design outline of the foundation pit is translated to the outside. Preferably, the translation distance is 80-100 cm, and a distance of 80-100 cm is reserved between the main structure of the foundation pit and the enclosure structure 4, which is used for laying self-adhesive waterproof rolls manually. Provide side wall waterproof membrane construction groove 3;

Step 2, construction preparations, including but not limited to the preparation of detailed waterproof construction technical plans, detailed technical disclosure, etc.;

Step 3, building the enclosure structure 4, the enclosure structure 4 in the present embodiment is an underground diaphragm wall, and the excavation of the foundation pit to the design value at the bottom of the pit is carried out to check the trench;

Step 4: Carry out waterproofing construction on the foundation pit bottom plate 5. Firstly, a 150cm thick C20 concrete cushion 7 is applied at the bottom of the foundation pit, and then a self-adhesive waterproof coiled material 2 is laid, and two adjacent self-adhesive waterproof coiled materials 2 are laid. The overlapping width of the joint should not be less than 10cm, so as to facilitate the seamless overlapping between the self-adhesive waterproof membranes 2, and then apply a 50cm thick C20 fine stone concrete protective layer 6, and finally apply the foundation pit floor 5.

Step five, pouring the main structure;

Step 6: Waterproof construction of the side wall 1 of the main structure; after the pouring of the side wall 1 of the main structure is completed, a self-adhesive waterproof roll is laid on the outside of the side wall 1 of the main structure from the bottom layer of the foundation pit in the side wall waterproof coil construction groove 3 Material 2, the overlapping width between two adjacent self-adhesive waterproof membranes 2 should not be less than 10cm, so as to facilitate the seamless overlap between the self-adhesive waterproof membranes 2.

In this embodiment, as shown in Figure 1, the main structure is three layers, and during the laying process of the self-adhesive waterproof roll material 2 in the step six, the self-adhesive waterproof roll material 2 is laid to the bottom floor of the second floor underground Stop laying at 11 o'clock at 10cm below 8, backfill in the side wall waterproof membrane construction groove 3 after taking soil, backfill to at least 10cm below the upper edge of the self-adhesive waterproof membrane 2 that has been laid, and compact the backfill 13; On the outside of the side wall 1 of the main structure, continue to lay the self-adhesive waterproof membrane 2 at least 10cm below the upper edge of the self-laid self-adhesive waterproof membrane 2, and the lap width of the laid self-adhesive waterproof membrane 2 is not less than 10cm , and the overlapping width of two adjacent self-adhesive waterproof rolls 2 is not less than 10cm, and the self-adhesive waterproof rolls 2 are laid to 10cm below the floor 9 of the ground floor. Backfill in the material construction groove 3, backfill to at least 10cm below the upper edge of the laid waterproof membrane 2, and compact the backfill 13; Continue laying the self-adhesive waterproof membrane 2 at least 10cm below the edge, and the lap width of the laid self-adhesive waterproof membrane 2 is not less than 10cm, and the overlap width of two adjacent self-adhesive waterproof membranes 2 is not less than 10cm, the self-adhesive waterproof membrane 2 is laid to the foundation pit roof 10, and the laying is stopped. After the soil is taken, it is backfilled in the side wall waterproof membrane construction groove 3, backfilled to the foundation pit roof 10, and the backfill soil 13 is compacted to complete the side wall of the main structure. Waterproof construction of walls.

It should be noted that the waterproof coiled material in the present invention is not limited to the self-adhesive waterproof coiled material in the embodiment of the present invention, as long as it can realize the waterproofing of the side wall. The outward translation distance of the design outline of the foundation pit in this embodiment is only a preferred solution of the present invention, as long as the distance value can be set to provide space for manual laying of the self-adhesive waterproof membrane. In the construction method of the waterproof structure of the deep foundation pit side wall of the subway station in the water-rich stratum of this embodiment, although step 4 is included in the waterproof construction of the bottom plate of the foundation pit, it does not mean that this step must be carried out. After step 3, step 5 and step Sixth, it is also possible to complete the construction of the side wall waterproof structure. The construction method of the waterproof structure of the side wall of the deep foundation pit of the subway station in the present invention is not limited to the case where the main structure is three layers in the embodiment, and the deep foundation of the subway station in the present invention can be applied when the main structure is one or more than two layers The construction method of the waterproof structure of the side wall of the pit: For example, when the main structure is one layer, during the laying process of the self-adhesive waterproof roll 2, the self-adhesive roll waterproof roll 2 is directly laid on the roof 10 of the foundation pit, and two adjacent self-adhesive rolls The lap width of the waterproof membrane 2 is not less than 10cm, and then the soil is backfilled and the backfill soil 13 is compacted; when the main structure is more than two layers, during the laying process of the self-adhesive waterproof membrane 2, the self-adhesive waterproof membrane 2 is laid Stop laying when it reaches 10cm below the upper floor of the bottom layer of the foundation pit, take soil and backfill in the side wall waterproof membrane construction groove 3 to at least 10cm below the upper edge of the laid self-adhesive waterproof membrane 2, and compact it Backfill soil 13, then continue to lay self-adhesive waterproof membrane 2 at least 10cm below the upper edge of the self-adhesive waterproof membrane 2 laid on the outside of the main structure side wall 1, and overlap with the laid self-adhesive waterproof membrane 2 The width is not less than 10cm, and the overlapping width of two adjacent self-adhesive waterproof membranes 2 is not less than 10cm. Repeat the laying process of the self-adhesive waterproof membrane 2 above until the self-adhesive waterproof membrane laid on the side wall 2 of the main structure The coiled material 2 is laid until the roof 10 of the foundation pit, and then soil is taken and backfilled to the roof 10 of the foundation pit and the backfill soil 13 is compacted to complete the waterproof construction of the side wall 1 of the main structure.

In this description, specific examples are used to illustrate the principle and implementation of the present invention. The description of the above embodiments is only used to help understand the method and core idea of the present invention; meanwhile, for those of ordinary skill in the art, according to this The idea of the invention will have changes in the specific implementation and scope of application. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims (10)

1. a kind of water rich strata Deep Foundation Pit of Metro Stations side wall waterproof construction, it is characterised in that include going along with sb. to guard him from outside to inside successively Structure sheaf, back fill course, waterproof roll layer and agent structure side wall layer, the waterproof roll layer are laid on the agent structure side On on the outside of wall layers.

2. water rich strata Deep Foundation Pit of Metro Stations side wall waterproof construction according to claim 1, it is characterised in that described anti- The waterproof roll of water coiled material layer is self-adhesive waterproof roll material.

3. a kind of construction method of water rich strata Deep Foundation Pit of Metro Stations side wall waterproof construction, it is characterised in that construction procedure is such as Under：

Step one, design of foundation pit contour line is translated laterally, reserves side wall waterproof coiled material construction groove；

Step 2, preparation of construction；

Step 3, applies building enclosure, excavates the foundation ditch；

Step 4, pours agent structure；

Step 5, after the completion for the treatment of that agent structure side wall is poured, in the side wall waterproof coiled material construction groove, from foundation ditch bottom in institute State and start laying water-proof coiled material on the outside of agent structure side wall, it is to be laid after the completion of fetch earth backfill and compacted backfill, complete main body The waterproof construction of structure side wall.

4. the construction method of water rich strata Deep Foundation Pit of Metro Stations side wall waterproof construction according to claim 3, its feature It is, the design of foundation pit contour line in the step one translates 80cm~100cm laterally.

5. the construction method of water rich strata Deep Foundation Pit of Metro Stations side wall waterproof construction according to claim 3, its feature It is, the preparation of construction in the step 2 includes working out detailed waterproof construction technology scheme, carries out detailed confide a technological secret.

6. the construction method of water rich strata Deep Foundation Pit of Metro Stations side wall waterproof construction according to claim 3, its feature It is, the building enclosure in the step 3 is diaphram wall, the excavation of foundation pit carries out check of foundation subsoil to after cheating bottom design load.

7. the construction method of the water rich strata Deep Foundation Pit of Metro Stations side wall waterproof construction according to claim 3, it is special Levy and be, carried out before the step 4 pours agent structure the waterproof construction of base plate of foundation pit, first in the foundation ditch Bottom apply 150cm thickness C20 concrete cushions, secondly laying water-proof coiled material, then apply 50cm thickness C20 pea gravel concretens protect Sheath, finally applies base plate of foundation pit.

8. the construction method of the water rich strata Deep Foundation Pit of Metro Stations side wall waterproof construction according to claim 3 or 7, it is special Levy and be, the waterproof roll is self-adhesive waterproof roll material, waterproof roll described in adjacent two width is taken during the waterproof roll laying Width is connect not less than 10cm.

9. the construction method of water rich strata Deep Foundation Pit of Metro Stations side wall waterproof construction according to claim 3, its feature It is, the agent structure is one layer, in the waterproof roll process of deployment in the step 5, and the volume waterproof material is straight Laying is connect to foundation ditch top plate, the lap width of waterproof roll described in adjacent two width is not less than 10cm, then fetch earth and backfill and tamp The backfill.

10. the construction method of water rich strata Deep Foundation Pit of Metro Stations side wall waterproof construction according to claim 3, its feature It is, the agent structure is more than two layers, in the waterproof roll process of deployment in the step 5, the waterproof volume Stop laying when material is laid to the bottom plate of the last layer of the foundation ditch bottom at least 10cm, in the side wall waterproof roll Fetch earth and be backfilled to below the waterproof roll top edge laid at least 10cm in construction groove, and tamp the backfill, Then controlled oneself on the outside of the agent structure side wall and continue to lay at least 10cm below the waterproof roll top edge of laying The waterproof roll, is not less than 10cm, and waterproof roll described in adjacent two width with the waterproof roll lap width laid Lap width nor less than 10cm, the process of deployment of the waterproof roll in repeating said steps five, until being laid on institute The waterproof roll stated on agent structure side wall is laid untill foundation ditch top plate.