CN102535488B - Waterproof construction method for bottom plate of high-water-level basement - Google Patents

Abstract

The invention discloses a waterproof construction method for a bottom plate of a high-water-level basement. The method comprises the following steps of: (1) partitioning water on a soil layer in a depth range of a foundation pit from the periphery of the foundation pit by using a waterproof curtain of a foundation pit support, and forming drainage ditches on the ground surface of the foundation pit support and at the bottom periphery of the foundation pit; (2) forming more than one dredging ditch below partitioning positions among pile bearing platforms, wherein the distance between the bottom of each pile bearing platform and the top of the dredging ditch is 500 to 1,000mm; and (3) forming a corresponding dewatering well at the periphery of the foundation pit according to a water outlet end of the dredging ditch, and arranging a submerged pump in the dewatering well, wherein the submerged pump is communicated with the drainage ditches through water suction pipes. The invention also discloses a waterproof system for the bottom plate of the high-water-level basement. By the method and the system, the problems of low dryness of flexible waterproof layer construction surfaces, over-high cost of jet grouting piles, high water seepage degree, high labor consumption, high material consumption and the like in the prior art are solved; and the system has the characteristics of effectively dewatering the basement, shortening construction periods, saving the cost and conveniently controlling construction quality, along with a simple structure, low manufacturing cost and the like.

Description

A waterproof construction method for basement floor with high water level

technical field

The invention relates to the technical field of basement floor waterproof construction in civil engineering, in particular to a high water level basement floor waterproof construction method and a system thereof.

Background technique

With the improvement of the level of underground engineering in architectural design, the use function of the basement will not only be used for underground air defense, underground garages and other purposes. Due to the shortage of urban construction land and following the popular trend of international buildings to expand space underground, the building use space (layer) is deeply expanded underground, and underground offices and underground commercial shopping plazas are becoming more and more diverse. At present, the basements of buildings in the low-lying alluvial areas of the Yangtze River and Pearl River Delta in my country are multi-layered, and the diversification of functions is becoming more and more prominent. The higher the requirements for the use of underground functions, the higher the requirements for the waterproof level of the basement; the higher the groundwater level, the greater the water pressure, and the greater the difficulty of construction.

The waterproof layer of the basement floor with high-level waterproof generally adopts the method of external anti-external sticking. Its waterproof structure is flexible waterproof layer→protective layer→roll material (dry laying) adhesive layer→protective layer→structural layer from the water-facing surface to the structural layer; and the first flexible waterproof layer at the forefront is a synthetic polymer waterproof coating film Or polyurethane coating film, the dryness of the cement mortar batch blocking base is very high, the higher the dryness of the base, the better the quality.

For foundation pits with high groundwater levels, especially the saturated muddy soil layers closer to rivers, lakes, and seaside areas, the installation of water-stop curtains cannot completely guarantee the drying of the base soil, because the huge water pressure will make the working pad of the basement floor Layer (concrete cushion) and the brick mold water permeability of the pile cap structure increase, resulting in water seepage of the base. Therefore, it is difficult for the base surface to reach the dryness required for the construction of the flexible waterproof layer synthetic polymer waterproof coating film or polyurethane coating film, and the construction quality is difficult to guarantee.

The most direct way to solve the problem of basement seepage in engineering is to use well point dewatering, that is, set dewatering well points around or inside the foundation pit to lower the groundwater level below the construction surface. However, for the surrounding geological environment that is more sensitive to groundwater, This method is not applicable. In addition, rotary spray piles can be used to stop water, that is, rotary spray piles can be installed at the position of water seepage to form a water-stop layer at the base. This approach can effectively solve the problem of base water seepage and ensure the dryness of the base, but the disadvantage of this method is that the cost is high and it takes a lot of time. Moreover, for foundation pits with high groundwater levels, the seepage situation is more serious , the shortcomings of this method are more prominent. A 100-200mm sand and pebble cushion can also be added under the concrete cushion. For foundation pits with a large area, vertical and horizontal blind ditches should also be set in the sand and gravel cushion to facilitate the drainage of water to the side ditches on both sides. This method can ensure that the base seepage water is quickly drained away, but in the case of a large foundation pit area, this method is more labor-intensive and material-intensive.

Contents of the invention

The purpose of the present invention is to overcome the shortcomings of the prior art above, and provide a waterproof construction method for high water level basement floor with simple structure, low cost, effective precipitation, shortened construction period, cost saving and convenient construction quality control.

Another object of the present invention is to provide a waterproof system for basement floor with high water level.

In order to achieve the above object, the present invention adopts the following technical solutions: a method for waterproofing construction of basement basement with high water level, comprising the following steps:

(1) First, use the water-stop curtain of the foundation pit support to stop the water in the soil layer in the depth range of the foundation pit from the periphery of the foundation pit, and at the same time set through drainage ditches on the ground supported by the foundation pit and around the bottom of the foundation pit;

(2) Set up more than one drainage ditch made of loose bricks and fiber nets below the interval between pile caps on the basement floor, and the distance between the bottom of the pile caps and the top of the drainage ditch is 500-1000mm;

(3) Corresponding dewatering wells are set at the outlet of the drainage ditch around the foundation pit. The dewatering wells are located outside the outermost edge of the basement foundation. A submersible pump is installed in the dewatering well, and the submersible pump is connected to the drainage ditch through a suction pipe.

As a preferred solution, the excavation method of the drainage ditch in the step (2) and the dewatering well in the step (3) is: when excavating the earthwork of the foundation pit to the elevation of half the height of the pile cap, according to the drainage The groundwork of the drainage ditch and the earthwork excavation of the precipitation well will be carried out at the same time after completion.

In order to avoid the basement floor structure and the position of the waterproof layer, the dewatering well in the step (3) is set beyond 600mm from the outermost peripheral edge of the basement foundation.

As a preferred solution, the construction method of the drainage ditch in the step (2) is: first lay a layer of pine bricks with a thickness of 60-120 mm at the bottom of the drainage ditch, and lay bricks with a thickness of 120-120 mm on both sides of the drainage ditch. 240mm loose bricks, the width of the inner space of the drainage ditch is 120-160mm, the inner space of the drainage ditch is loosely filled with gravel with a particle size of 20-30mm, and the top of the drainage ditch is tiled with loose bricks with a thickness of 60-120mm and a length of 240mm , leave a 30-60mm wide drainage joint between the top pine bricks and pine bricks, and then lay 2-3 layers of fiber mesh on the upper surface of the top pine bricks and the outer surfaces of the pine bricks on both sides of the drainage ditch. 9 to 16 meshes per centimeter, and at the same time, the bottom of the drainage ditch and the dewatering well have a slope of 0.5 to 1%, so that the water in the ditch can be smoothly drained to the dewatering well.

As a preferred solution, the planar arrangement of the hydrophobic grooves in the step (2) is a full-length through structure or a non-through-length through structure. It is only necessary to ensure that the outlet end of the drain ditch is connected with the precipitation well.

As another preferred solution, the planar arrangement of the drainage ditch in the step (2) is a curved structure, and the outlet end of the drainage ditch communicates with the precipitation well in the step (3).

A high water level basement floor waterproofing system, comprising pile caps, drains, drainage ditches, dewatering wells and submersible pumps; wherein, at the bottom of the interval between pile caps, there is more than one pine brick and fiber net. The bottom of the pile cap is 500-1000mm away from the top of the drainage ditch. The ground supported by the foundation pit and the periphery of the foundation pit bottom are provided with a through-drainage ditch. The corresponding dewatering wells are connected, and a submersible pump is arranged in the dewatering well, and the submersible pump is connected with the drainage ditch through a suction pipe.

As a preferred solution, the drain ditch is laid with a layer of 60-120mm loose bricks at the bottom, and loose bricks with a thickness of 120-240mm are laid on both sides, and the width of the inner space is 120-160mm. Loosely fill gravel with a particle size of 20-30mm, pave loose bricks with a thickness of 60-120mm and a length of 240mm on the top of the drainage ditch, and leave a 30-60mm wide drainage joint between the top loose bricks and loose bricks. The upper surface of the pine bricks on the top of the ditch and the outer surface of the pine bricks on both sides are laid with 2 to 3 layers of fiber mesh, the fiber mesh is 9 to 16 meshes per square centimeter, and the bottom of the drainage ditch and the precipitation well have a slope of 0.5 to 1%.

In order to support the pressure of the soil and enable good drainage, the dewatering well includes a reinforcement cage, a stiffening ring, stirrups and a water filter net; wherein, the stirrups are helically fixed on the reinforcement cage, and the stiffening ring is sleeved and fixed on the reinforcement On the cage, the outside of the steel cage is covered with more than 3 layers and has 9 to 12 mesh water filter nets per square centimeter. The length of the steel cage is less than or equal to 4.5m and is less than the depth of the foundation pit supporting piles. The precipitation The well is located 600mm away from the outermost edge of the basement foundation. The main functions of the precipitation well are water collection, precipitation and pumping and drainage. The size of the precipitation well is designed according to the drainage capacity of the drainage ditch.

In order to better drain water, filter and prevent clogging, a travel switch is also included. The travel switch is arranged on the inner wall of the dewatering well above the submersible pump. The head of the submersible pump is more than 30m and the diameter is more than 50mm. Quality PVC pipe, the connection between the hard PVC pipe and the water outlet of the submersible pump is connected with a 300-500mm long hose for vibration reduction.

Compared with the prior art, the present invention has the following advantages and effects:

1. Adopting the construction method of the present invention can effectively dewater and provide a working surface for the next process, avoiding the failure to enter a process due to precipitation failure or water accumulation in the past, and can greatly reduce the construction period.

2. Structures such as drainage ditch and dewatering well in the present invention use simple and cheap materials and can effectively ensure the dryness of the waterproof base of the basement floor, saving the cost of rework of the waterproof layer construction caused by the failure of precipitation or water accumulation in the past.

3. By adopting the construction method of the present invention, the dryness of the base of the basement floor and the construction quality of the waterproof layer are guaranteed, and the pass rate of waterproof layer inspection and acceptance is more than 100%, and the excellent quality rate is more than 90%.

4. Both the fiber net and the water filter net in the present invention can adopt the old safety net, waste utilization and cost saving.

5. The bottom of the drainage ditch in the present invention has a slope of 0.5-1% with the precipitation well, which has the feature of making water flow to the drainage ditch more easily.

6. The dewatering well in the present invention comprises a reinforcement cage, a stiffening ring, stirrups and a water filter net, and the length of the reinforcement cage is less than or equal to 4.5m and less than the depth of penetration of the foundation pit support piles of the foundation pit support, and has the ability to effectively The supporting soil pressure and the excavator are divided into two levels of platforms to dig pits and bury them.

7. The suction pipe in the present invention is a hard PVC pipe to prevent the water suction pipe from being blocked by silt, and the vibration damping at the joint between the hard PVC pipe and the water outlet of the submersible pump is connected with a 300-500mm long hose.

Description of drawings

Fig. 1 is the structural representation of high water level basement floor waterproofing system of the present invention;

Fig. 2 is the sectional view of high water level basement floor waterproofing system of the present invention;

Fig. 3 is the plane layout drawing of the drainage ditch of the basement floor waterproofing system of the present invention;

Fig. 4 is the cross-sectional view of the drainage ditch of the waterproof system of the basement basement with high water level of the present invention;

Fig. 5 is a structural schematic diagram of the dewatering well of the high water level basement floor waterproofing system of the present invention.

The labels and names in the figure are as follows:

Detailed ways

For the convenience of those skilled in the art to understand, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

Example 1:

As shown in Figures 1 to 5, a waterproof construction method for a basement floor with a high water level comprises the following steps:

(1) First, use the water-stop curtain of the foundation pit support to stop the water in the soil layer in the depth range of the foundation pit 18 from the periphery of the foundation pit 17, and at the same time, set a through hole on the ground 17 of the foundation pit support and the periphery of the bottom of the foundation pit. gutter 1;

(2) Set up more than one drain ditch 3 made of loose bricks and fiber nets below the interval between the pile caps of the basement floor, and the bottom 2 of the pile caps is 500-1000mm away from the top of the drain ditch 3;

(3) Corresponding dewatering wells 4 are arranged at the outlet of the drainage ditch 3 around the foundation pit 1, and the dewatering wells 4 are arranged outside the outermost edge 5 of the basement foundation. It communicates with the drainage ditch 1 through the suction pipe 7 .

Among them, the high water level refers to the saturated muddy soil layer where the foundation pit is located close to rivers, lakes, and seaside areas. The drying of the soil.

As shown in Figure 1, the excavation method of the drainage ditch 3 in the step (2) and the dewatering well 4 in the step (3) is: when the excavation of the excavation of the foundation pit 1 is excavated to the elevation of half the height of the pile cap, Carry out measuring and setting out according to the floor plan of drain ditch 3 and dewatering well 4, carry out the earth excavation of drain ditch 3 and the earth excavation of dewatering well 4 simultaneously after completion, dewatering well 4 in described step (3) is located at 600mm away from the outermost edge of the basement foundation 5. The planar arrangement of the hydrophobic grooves 3 in the step (2) is a full-length through structure or a non-through-length through structure, and the hydrophobic grooves 3 in this embodiment are all linear structures.

As shown in Figure 4, the construction method of the drain ditch 3 in the step (2) is as follows: a layer of loose bricks 12 with a thickness of 60 to 120 mm is tiled at the bottom of the drain ditch 3 first, and a thickness of pine brick 12 is laid on both sides of the drain ditch 3 pine bricks 13 of 120-240 mm, the width of the inner space of the drainage ditch 3 is 120-160 mm, the inner space of the drainage ditch 3 is loosely filled with crushed stones 19 with a particle size of 20-30 mm, and the top tile thickness of the drainage ditch 3 is 60-160 mm. 120mm long pine bricks 14 with a length of 240mm, leave a 30-60mm wide drainage joint 15 between the top pine bricks 14 and pine bricks, and then lay on the upper surface of the top pine bricks 14 of the drainage ditch and the outer surfaces of the pine bricks 13 on both sides 2～3 layers of fiber nets 16, the fiber nets 16 are 9～16 meshes per square centimeter, and the bottom of the drain ditch 3 and the dewatering well 4 have a slope of 0.5～1% simultaneously, so that the water in the ditch is drained to the dewatering well smoothly. The function of the fiber net 16 is: the water of the soil can be drained in the drainage ditch 3 and the soil is blocked outside the drainage ditch 3 to keep it unimpeded.

Among them, the cross-sectional size and layout density of the drainage ditch 3 are determined according to the calculation of the water inflow in the soil layer where the basement bottom pile cap is located, so as to ensure that the water inflow is discharged to the precipitation well 4 through the underground drainage ditch 3 and drained to the drainage ditch 1 row Walk; The diameter of the dewatering well 4 and the pumping capacity of the submersible pump 6 are determined by the displacement of the drainage ditch. After the basement construction is completed, the dewatering well in the foundation pit will be backfilled together with the side wall soil of the basement, and its steel cage can be taken out and reused before backfilling.

A high water level basement floor waterproofing system, comprising pile caps, drainage ditch 3, drainage ditch 1, dewatering well 4 and submersible pump 6; wherein, one or more loose bricks and The drainage ditch 3 made of fiber mesh, the bottom 2 of the pile cap is 500-1000mm away from the top of the drainage ditch 3, the ground 17 supported by the foundation pit and the periphery of the bottom of the foundation pit are provided with a through drainage ditch 1, the outermost edge 5 of the basement foundation A dewatering well 4 is set, and the outlet end of the drainage ditch 3 communicates with the corresponding dewatering well 4, and a submersible pump 6 is arranged in the dewatering well 4, and the submersible pump 6 communicates with the drainage ditch 1 through a suction pipe 7.

As shown in Figure 4, the drainage ditch 3 is laid with a layer of 60-120mm loose bricks at the bottom, and loose bricks with a thickness of 120-240mm are laid on both sides, and the inner width of the drainage ditch 3 is 120-160mm. Fill the void with gravel 19 with a particle size of 20-30 mm, pave loose bricks 14 with a thickness of 60-120 mm and a length of 240 mm on the top of the drainage ditch 3, and leave a 30-60 mm wide gap between the loose bricks 14 on the top and the loose bricks. Drainage joint 15, the top pine brick 14 upper surface of drain ditch and the pine brick 13 outer surfaces of both sides are laid 2～3 layers of fiber net 16, and fiber net 16 is 9～16 meshes per square centimeter, simultaneously the bottom of drain ditch 3 and The precipitation well 4 has a slope of 0.5-1%. The function of the fiber net 16 is: the water of the soil can be drained in the drainage ditch 3 and the soil is blocked outside the drainage ditch 3 to keep it unimpeded.

As shown in Figure 5, the dewatering well 4 includes a reinforcement cage 8, a stiffening ring 9, a stirrup 10 and a water filter 11; wherein, the stirrup 10 is spirally welded on the reinforcement cage 8, and the stiffening ring 9 is set and welded on the reinforcement On the cage 8, the reinforcement cage 8 is covered with more than 3 layers and has 9 to 12 mesh water filter screens 11 per square centimeter, and the length of the reinforcement cage 8 is less than or equal to 4.5m and less than the depth of the foundation pit support piles for foundation pit support. , the dewatering well 4 is arranged outside the 600mm distance from the outermost peripheral edge 5 of the basement foundation, and also includes a travel switch. The travel switch is arranged on the inner wall of the dewatering well 4 above the submersible pump 6, and the head of the submersible pump 6 is more than 30m. More than 50mm in diameter, the suction pipe 7 is a rigid PVC pipe, and the main functions of the dewatering well 4 are water collection, dewatering and pumping and drainage. The size of the dewatering well 4 and the specifications of the submersible pump 6 are all set according to actual needs. Suction pipe 7 can not be flexible pipe, must use hard PVC pipe, in order to avoid the sand in the water that pumps up pipe is blocked, and the damping of its hard PVC pipe and the water outlet joint of submersible pump is connected with 300～500mm long flexible pipe. Water filter net 11 and fiber net 16 all can adopt old safety net to replace, reach the effect of waste utilization. After the basement construction is completed, the dewatering well in the foundation pit will be backfilled together with the side wall soil of the basement, and its steel cage can be taken out and reused before backfilling.

Example 2:

The difference between this embodiment and Embodiment 1 lies in that the planar layout of the drain ditch 3 in the step (2) is a curved structure, and the outlet end of the drain ditch 3 communicates with the dewatering well 4 in the step (3). That is to say, the drainage ditch 3 in the present embodiment can be bent between the caps, as long as the water can be sent to the dewatering well 4.

The specific implementation described above is a preferred embodiment of the present invention, and does not limit the present invention. Any other changes or other equivalent replacement methods that do not deviate from the technical solution of the present invention are included in the scope of protection of the present invention. within.

Claims (5)

1. a high water level waterproof construction method for bottom plate of basement, is characterized in that, comprises the following steps:

(1) first utilize the water-stop curtain of pattern foundation pit supporting structure, by the water of foundation depth scope soil layer, only every beyond foundation ditch periphery, ground and the foundation ditch bottom perimeter at pattern foundation pit supporting structure all arranges perforation gutter simultaneously;

(2) the hydrophobic ditch that more than 1 the loose brick of use and fleece are built into is set below the interval location between basement bottom board pile cap, pile cap bottom is apart from hydrophobic ditch top 500～1000mm, the construction method of described hydrophobic ditch is: the loose brick that is first 60～120mm in the bottom of hydrophobic ditch tiling a layer thickness, the loose brick that the equal laying depth in hydrophobic ditch both sides is 120～240mm, the inner space width of hydrophobic ditch is 120～160mm, the interior empty pine of hydrophobic ditch is filled out the rubble that particle diameter is 20～30mm, the top tiling thickness of hydrophobic ditch is that 60～120mm length is the loose brick of 240mm, between the loose brick at top and loose brick, stay the wide sluicing seam of 30～60mm, then at the top of hydrophobic ditch pine brick upper surface and both sides pine brick external surface, lay 2～3 layers of fleece, fleece is every square centimeter of 9～16 orders, bottom and the dewatering well of hydrophobic ditch have 0.5～1% the gradient simultaneously, water in ditch is drained toward dewatering well smoothly,

(3) at foundation ditch periphery, by hydrophobic ditch water outlet end, corresponding dewatering well is set, dewatering well is located at the outside apart from basement basis outermost peripheral, and submersible pump is set in dewatering well, and submersible pump is communicated with gutter by drinking-water pipe.

2. high water level waterproof construction method for bottom plate of basement according to claim 1, it is characterized in that, the excavation method of the dewatering well in the hydrophobic ditch in described step (2) and step (3) is: when pit earthwork digs to the absolute altitude of half height of pile cap, according to the layout plan of hydrophobic ditch and dewatering well, measure unwrapping wire, after completing, carry out the soil excavation of hydrophobic ditch and the soil excavation of dewatering well simultaneously.

3. high water level waterproof construction method for bottom plate of basement according to claim 1, is characterized in that: the dewatering well in described step (3) is located at apart from beyond the outermost peripheral 600mm of basement basis.

4. high water level waterproof construction method for bottom plate of basement according to claim 1, is characterized in that: the hydrophobic ditch layout in described step (2) is elongated communicating structure or non-elongated communicating structure.

5. high water level waterproof construction method for bottom plate of basement according to claim 1, is characterized in that: the hydrophobic ditch layout in described step (2) is for curving structure, and hydrophobic ditch water outlet end is communicated with the dewatering well in step (3).

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