CN221001034U - Vacuum supporting structure of deep foundation pit close to existing building - Google Patents
Vacuum supporting structure of deep foundation pit close to existing building Download PDFInfo
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- CN221001034U CN221001034U CN202322573136.9U CN202322573136U CN221001034U CN 221001034 U CN221001034 U CN 221001034U CN 202322573136 U CN202322573136 U CN 202322573136U CN 221001034 U CN221001034 U CN 221001034U
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- Investigation Of Foundation Soil And Reinforcement Of Foundation Soil By Compacting Or Drainage (AREA)
Abstract
The utility model discloses a deep foundation pit vacuum supporting structure close to an existing building, which comprises a transverse drainage body arranged in a certain range outside the edge of a foundation pit, wherein a vertical drainage body and a vertical reinforcement body are arranged in soil body below the transverse drainage body at intervals, the top of the transverse drainage body is sealed through a horizontal sealing layer, the transverse drainage body is connected with a vacuum pumping and draining system, the outer edge of the horizontal sealing layer is sealed through a peripheral vertical sealing curtain, the horizontal sealing layer extends downwards at the edge of the foundation pit to form a slope sealing layer paved on the vertical pit wall of the foundation pit, and the slope sealing layer extends to the pit bottom and is in sealing connection with a slope bottom vertical sealing curtain arranged in the slope foot soil body of the pit bottom. The utility model has the double functions of soil blocking and water stopping, and simultaneously organically combines an inner support supporting system on the premise of not damaging a slope sealing layer, supports non-sloping excavation with excavation depth exceeding 10m, and has obvious cost advantage and construction period advantage compared with a supporting mode of drilling piles or ground connecting walls and inner supports.
Description
Technical Field
The utility model relates to the technical field of foundation pit support of civil construction, in particular to a deep foundation pit vacuum support structure close to an existing building.
Background
The method for reinforcing the foundation by vacuum preloading is characterized in that the ground is reinforced by taking atmospheric pressure as preloading load, a permeable sand cushion layer is paved on the surface of the foundation, a layer of airtight sealing film is covered on the permeable sand cushion layer, the periphery of the permeable sand cushion layer is sealed by sealing walls to isolate the permeable sand cushion layer from the atmosphere, drainage channels are buried in the sand cushion layer and the soil body, the permeable sand cushion layer is communicated with a vacuum pump to carry out vacuumizing, negative pressure is formed in the drainage channels in the sand cushion layer and the soil body, pore water and air in the soil body are gradually sucked out, and therefore the soil body is consolidated and the strength is improved.
The vacuum preloading method is also widely applied in the field of foundation pit support, and the continuous vacuum effect is applied to maintain pit wall stability during the whole foundation pit excavation period.
The Chinese patent CN201210295813.9 discloses a vacuum action gravity type foundation pit supporting system and a construction method, the method uses a vacuum action gravity type pit wall supporting structure to support, and can realize larger excavation depth, but the precondition is that enough implementation space is needed to be arranged outside the excavation range to set gravity type retaining walls and slope releasing, and the modern city is narrow in space, so that the application range is greatly limited.
The Chinese patent CN200810236142.2 discloses a method for excavating a deep foundation pit by vacuum curtain water stop and atmospheric pressure support, which uses the vacuum curtain water stop and the atmospheric pressure to support the foundation pit, is convenient for excavating, but cannot adapt to the condition of large excavation depth, and the method needs to set a side wall curing wall body, thereby increasing the engineering quantity and being disadvantageous to reducing the manufacturing cost.
With the increasing of building projects, the problem of land shortage is increasingly highlighted, and the situation that the existing building exists at the periphery of the foundation pit is unavoidable. Soil loss and stress state change are often caused during foundation pit construction, so that the influence on adjacent existing buildings is caused, for example, peripheral soil deformation is caused during foundation pit construction, and inclination deformation of adjacent houses is easily caused. Therefore, when constructing the foundation pit adjacent to the existing building, it is important to reduce the influence on the existing building, and how to excavate the deep foundation pit by vacuum action under the condition that the setting area of the adjacent existing object and the supporting structure is limited so as to reduce the construction cost is a technical problem to be solved.
Disclosure of utility model
The utility model aims to provide a deep foundation pit vacuum supporting structure close to an existing building, which aims to solve the technical problems in the background technology.
In order to achieve the technical purpose, the utility model adopts the following technical scheme:
the utility model provides a near deep basal pit vacuum supporting construction of existing building, includes the horizontal drainage body that sets up in the certain within range in foundation ditch edge outside, vertical drainage body and vertical reinforcement body have been arranged to the interval in the soil body of horizontal drainage body below, vertical drainage body and vertical reinforcement body evenly arrange in the horizontal drainage body setting range, and both bottom elevations are less than the biggest pit bottom elevations of foundation ditch, the top elevation of vertical drainage body is higher than foundation ditch outside ground elevations and inserts in the horizontal drainage body and the horizontal drainage body intercommunication, horizontal drainage body top is sealed through horizontal airtight layer, and horizontal drainage body links to each other with the vacuum drainage system, be provided with peripheral vertical airtight curtain in the soil body of horizontal airtight layer outside edge position, and horizontal airtight layer and peripheral vertical airtight curtain top sealing connection, horizontal airtight layer extends down in foundation ditch edge position and forms the domatic airtight layer of laying on the vertical pit wall of foundation ditch, domatic airtight layer extends to the pit bottom to the slope bottom to with the slope bottom vertical airtight curtain sealing connection of setting in the soil body of pit bottom slope foot position.
Preferably, the foundation pit is characterized by further comprising upright posts arranged in soil body at the inner side of the pit wall of the foundation pit, wherein the upright posts are arranged in a circle at intervals along the edge of the foundation pit, and the upright posts are arranged close to the excavation surface.
Preferably, one side of the slope airtight layer, which is close to the interior of the foundation pit, is provided with an enclosing purlin and a cross brace, the enclosing purlin is fixed on the upright post pile through a dowel bar and is separated from the slope airtight layer, one end of the dowel bar is fixedly connected with the enclosing purlin, the other end of the dowel bar penetrates through the slope airtight layer and the soil body on the inner side of the slope airtight layer and is fixedly connected with the upright post pile, the dowel bar is sealed with the seam of the slope airtight layer, the cross brace is fixed on the enclosing purlin, the dowel bar, the enclosing purlin and the cross brace form a foundation pit internal support system, and the dowel bar, the enclosing purlin and the cross brace are all arranged in the foundation pit at the same vertical interval.
Preferably, a grouting bag for adjusting the deformation of the foundation around the existing building is buried in the soil body between the peripheral vertical airtight curtain and the existing building.
Preferably, a pile carrier is arranged at the top of the horizontal airtight layer, and the pile carrier needs to be removed before the foundation pit is excavated.
Preferably, the vertical drainage bodies and the vertical reinforcement bodies are distributed according to a rectangular array or a triangular array.
Preferably, the vertical reinforcement body is made of screw steel, the upright post pile, the enclosing purlin and the transverse strut are all made of H-shaped steel, and the dowel steel is made of steel pipes.
Compared with the prior art, the utility model has the beneficial effects that: the utility model essentially belongs to a structural retaining wall, which has the dual functions of retaining and water stopping, the permanent strength of soil body at the outer side of a foundation pit is improved through the vacuum consolidation, the temporary strength of the soil body is improved through the increase of the effective stress of the soil body caused by the negative pressure of soil body pores, the reinforced soil body with the strength of the permanent strength and the temporary strength is tightly combined with a vertical reinforcement body to form a reinforced soil with vertical reinforcement, the self stability of the side wall of the foundation pit can be greatly improved, meanwhile, the inner supporting and supporting system is organically combined on the premise of not damaging a slope sealing layer, the stability of the pit wall is effectively ensured under the synergistic effect of the self stability of the reinforced soil body and the supporting force provided by the inner supporting system, the non-slope excavation with the excavation depth exceeding 10m and the vertical excavation without the diaphragm wall are supported, the construction cost advantage and the construction period advantage are obvious compared with the support mode of the bored pile or the diaphragm wall and the internal support, in addition, the vacuum pumping and slope sealing layer also has the functions of water stopping and precipitation, no extra water stopping and precipitation measures are needed, meanwhile, the arrangement of the vertical reinforcement body and the pile carrier can effectively counteract the inward shrinkage deformation of the foundation pit outer soil body caused by the vacuum effect, the influence of the foundation pit vacuum support and the excavation process on the adjacent existing building is prevented, the arrangement of the grouting bag can be used as a further insurance measure, and when the foundation of the surrounding existing building is greatly deformed, the grouting operation is timely carried out on the grouting bag so as to control the settlement and horizontal deformation of the foundation of the surrounding environment, and the safety of the surrounding environment is ensured.
Drawings
The foregoing and/or other aspects and advantages of the present utility model will become more apparent and more readily appreciated from the detailed description taken in conjunction with the following drawings, which are meant to be illustrative only and not limiting of the utility model, wherein:
FIG. 1 is a schematic cross-sectional structure of a foundation pit before excavation;
FIG. 2 is a schematic cross-sectional view of the foundation pit of the present utility model after excavation;
FIG. 3 is a schematic plan view of the present utility model in a localized position near the edge of a pit.
Reference numerals: 1. ground surface; 2. existing buildings; 3. grouting bags; 4. a peripheral vertical airtight curtain; 5. a horizontal sealing layer; 6. stacking carriers; 7. a lateral drainage body; 8. a dowel bar; 9. enclosing purlin; 10. a cross brace; 11. a slope sealing layer; 12. maximum pit bottom digging; 13. a slope bottom vertical airtight curtain; 14. upright post piles; 15. a vertical drainage body; 16. and (5) vertically adding the rib body.
Detailed Description
Hereinafter, an embodiment of a deep foundation pit vacuum supporting structure adjacent to an existing building of the present utility model will be described with reference to the accompanying drawings. The examples described herein are specific embodiments of the present utility model, which are intended to illustrate the inventive concept, are intended to be illustrative and exemplary, and should not be construed as limiting the utility model to the embodiments and scope of the utility model. In addition to the embodiments described herein, those skilled in the art can adopt other obvious solutions based on the disclosure of the claims and specification, including those adopting any obvious substitutions and modifications to the embodiments described herein.
In the description of the present utility model, it should be noted that the terms "front", "rear", "left", "right", "top", "bottom", "upper", "lower", "inner", "outer", "transverse", "longitudinal", "vertical", "oblique", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are merely for convenience in describing the present utility model and simplifying the description, and do not indicate or imply that the apparatus or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
The drawings in the present specification are schematic views, which assist in explaining the concept of the present utility model, and schematically show the shapes of the respective parts and their interrelationships. Note that, in order to clearly show the structures of the components of the embodiments of the present utility model, the drawings are not drawn to the same scale. Like reference numerals are used to denote like parts.
The principles and features of the present utility model are described below with reference to the drawings, the illustrated embodiments are provided for illustration only and are not intended to limit the scope of the present utility model. The preferred embodiments of the present utility model will be described in further detail below in conjunction with certain engineering examples and the descriptions of fig. 1-3.
Example engineering introduction:
In certain foundation pit engineering, the excavation size of the foundation pit is 36m multiplied by 32m multiplied by 17m, the excavation depth of the foundation pit is 17m, the existing building 2 exists at the periphery of the foundation pit, the range for arranging the horizontal sealing layer 5 to implement vacuum preloading is limited, and large-area slope excavation cannot be carried out;
foundation pit field foundation soil layer condition:
① 0-22 m, light yellow brown or gray clay, natural volume weight gamma=17.9 kN/m 3, water content 26%, void ratio 0.89, plasticity index I p =24, non-drainage shearing adhesion force C u =10.0 kPa, non-drainage shearing internal friction angle phi u =19.0 degrees, permeability coefficient k less than or equal to 1×10 -7 m/s, standard penetration number 13, basic bearing capacity sigma 0 =81.3 kPa, and general engineering property;
② The yellow brown silt is below 22m, contains a small amount of fine sand, has no drainage shear adhesion force of C u =0.1 kPa, has no drainage shear internal friction angle phi u =35.0 degrees, is compact to very compact, has standard penetration number of more than 50, has basic bearing capacity sigma 0 =526 kPa, and has good engineering property.
As shown in fig. 1-3, a deep foundation pit supporting structure suitable for use in an existing building comprises the following parts:
The setting range of the pit top horizontal airtight layer 5 is 39m multiplied by 35m, the outer side edge of the pit top horizontal airtight layer is sealed and blocked by adopting a peripheral vertical airtight curtain 4, the peripheral vertical airtight curtain 4 has two setting modes, one can be realized by constructing a sealing steel sheet pile, the other can be realized by vertically slotting and paving a geomembrane, and the 3m deep sealing steel sheet pile which is vertically arranged is used as the peripheral vertical airtight curtain 4 in the embodiment;
Grouting bags 3 are arranged in the foundation outside the peripheral vertical airtight curtain 4, and the diameter of each grouting bag 3 is 30cm, the length is 3m, and the burial depth is 2m in the embodiment;
The vertical drainage bodies 15 and the vertical reinforcement bodies 16 are arranged in foundation soil within the arrangement range of the pit top horizontal airtight layer 5, the vertical drainage bodies 15 and the vertical reinforcement bodies 16 are arranged in a rectangular array or a triangular array, in the embodiment, the vertical drainage bodies 15 are SPB-B plastic drainage plates, the depth is 21m, the rectangular array is arranged, the center distance is 0.6m, the top elevation is 0.3m higher than the elevation of the pit top ground 1 so as to be inserted into the horizontal drainage bodies 7, the bottom elevation is 4m lower than the elevation of the maximum pit bottom 12, the vertical reinforcement bodies 16 are arranged in a rectangular array and are alternately arranged with the vertical drainage bodies 15, the center distance is 0.6m, the top elevation is the same as the elevation of the pit top ground 1, and the bottom elevation is 3m lower than the elevation of the maximum pit bottom 12;
The pile carrier 6 is arranged on the pit top horizontal sealing layer 5, the arrangement range of the pile carrier 6 is determined according to the calculation of the size of the foundation pit, in the embodiment, 3m high filling soil is adopted as the pile carrier 6, and in the embodiment, the pile carrier 6 is arranged only in the range of the pit outer horizontal sealing layer 5;
The horizontal drainage body 7 is arranged on the surface of foundation soil at the top end of the vertical drainage body 15, the horizontal drainage body 7 is formed by a sand cushion layer formed by medium coarse sand with the thickness of 0.5 meter, PVC vacuum filter pipes with phi 50mm which are distributed in a grid shape are horizontally distributed in the middle of the thickness of the sand cushion layer, the longitudinal and transverse intervals of the filter pipes are 8m, the vacuum filter pipes are connected to a vacuum pressure source (such as a vacuum pump) through vacuum pipes penetrating through the horizontal sealing layer 5, and sealing treatment is carried out at the joint of the vacuum pipes and the horizontal sealing layer 5;
Two layers of HDPE geomembrane with the thickness of 0.2mm are paved on the surface of the transverse drainage body 7 to serve as a horizontal airtight layer 5, the outer side edge of the horizontal airtight layer 5 is connected with the upper end of the peripheral vertical airtight curtain 4 in a sealing way, two layers of 200g/m 2 geotextile are paved on two sides of the horizontal airtight layer 5 to serve as protection geomembranes;
Paving a slope surface sealing layer 11 on the vertical pit wall of the foundation pit, wherein the slope surface sealing layer 11 is formed by covering a reserved part of the horizontal sealing layer 5 on the excavation side of the foundation pit on the newly excavated pit wall, two layers of 200g/m 2 geotextile are paved on two sides of the slope surface sealing layer 11 for protecting the slope surface sealing layer, and protection devices such as wood boards are arranged on the horizontal sealing layer 5 and the geotextile on the outer side of the slope surface sealing layer 11 in the actual construction process to seal and protect the slope surface sealing layer 11 so as not to damage the slope surface sealing layer 11 due to construction disturbance;
The bottom boundary of the slope surface airtight layer 11 is sealed and plugged by adopting a slope bottom vertical airtight curtain 13, the slope bottom vertical airtight curtain 13 also has two setting modes, one can be realized by constructing a sealing steel sheet pile, the other can be realized by vertically slotting and paving a geomembrane, and in the embodiment, the slope bottom vertical airtight curtain 13 is formed by using a 2m deep sealing steel sheet pile vertically arranged at the position of a pit bottom slope foot;
A circle of upright posts 14 formed by 400X 400H-shaped steel with the depth of 24m and the center-to-center spacing of 600mm along the edge of the foundation pit, wherein the upright posts 14 are arranged in soil in the pit wall and are close to the excavation surface of the foundation pit;
The dowel steel comprises a dowel steel 8 formed by steel pipes with the length of 20cm, the outer diameter of 15cm and the wall thickness of 10mm, an enclosing purlin 9 formed by 400X 400H-shaped steel, the enclosing purlin 9 positioned on a free surface is connected with the surface of a column pile 14 by the dowel steel 8 through a slope sealing layer 11, the dowel steel 8 passes through the slope sealing layer 11 to be subjected to sealing treatment, a transverse support 10 formed by double-spliced 400X 400H-shaped steel is used for bearing horizontal force borne by the enclosing purlin 9, an inner supporting system is formed by the column pile 14, the dowel steel 8, the enclosing purlin 9 and the transverse support 10, and the dowel steel 8, the enclosing purlin 9 and the transverse support 10 are all arranged at the same vertical interval.
The utility model discloses a vacuum support excavation method suitable for a deep foundation pit adjacent to an existing building, which comprises the following steps:
Step S1, arranging upright posts 14 in the soil body in the wall outside the excavation range housing of the foundation pit and close to the excavation surface;
Step S2, arranging a vertical drainage body 15 in the soil body of the excavation range of the foundation pit, and arranging the vertical drainage body 15 and a vertical reinforcement body 16 in the soil body outside the excavation range of the foundation pit within a range defined according to the design in a construction drawing, wherein the bottom heights of the vertical drainage body 15 and the vertical reinforcement body 16 are lower than the maximum pit bottom 12 height of the foundation pit, and the top heights of the vertical drainage body 15 and the vertical reinforcement body 16 are not lower than the top heights of the upright post piles 14;
S3, vertically arranging a peripheral vertical closed curtain 4 downwards from the pit top ground 1 at the boundary outside the arrangement range of the vertical drainage body 15 and the vertical reinforcement body 16;
step S4, arranging grouting bags 3 in the foundation between the peripheral vertical closed curtain 4 and the existing building 2;
s5, arranging a transverse drainage body 7 at the top of the distribution range of the vertical drainage body 15, ensuring that the top end of the vertical drainage body 15 is inserted into the transverse drainage body 7 to be communicated with the transverse drainage body 7, and arranging a grid-shaped vacuum filter tube inside the transverse drainage body 7;
s6, paving a horizontal sealing layer 5 on the top surface of the transverse drainage body 7, and sealing and connecting the edge of the horizontal sealing layer 5 with the top of the peripheral vertical sealing curtain 4;
Step S7, connecting the vacuum filter tube arranged in the step S5 to a vacuum pressure source through a vacuum tube penetrating through the horizontal sealing layer 5, and performing sealing treatment at the joint of the vacuum tube and the horizontal sealing layer 5;
Step S8, starting a vacuum pressure source, after the foundation soil consolidation degree below the horizontal closed layer 5 meets the stacking requirement (the consolidation degree is required to reach 50% in the embodiment), arranging a layer of 400g/m 2 geotextile on the horizontal closed layer 5 to protect the horizontal closed layer 5, adding a stacking carrier 6 in three stages, wherein each stage is 1m high, and the application time interval of each stage is 1 week;
Step S9, continuously vacuumizing through a vacuum pressure source, removing a pile carrier 6 after the foundation soil consolidation degree meets the excavation requirement (in the embodiment, the foundation soil consolidation degree reaches 70% according to the 3m high pile loading condition), cutting off a horizontal sealing layer 5 in the excavation range of the foundation pit, sealing and lengthening a slope sealing layer 11 to the horizontal sealing layer 5 at a cutting position, burying the slope sealing layer 11 in an excavated sealing groove for sealing and burying, and excavating the foundation pit under the condition of continuously vacuumizing;
Step S10, each time a certain depth is excavated (the depth of each excavation is set to be 1m in the embodiment, so that obvious loss of sealing effect is not considered, and excavation construction efficiency is considered), the slope sealing layer 11 is lifted out of the self-sealing ditch and covered on the pit wall of a foundation pit formed by new excavation, and then the slope sealing layer 11 is embedded into the newly excavated sealing ditch again for storage;
step S11, when the depth reaches the design elevation of the next internal support system by the method in step S10, welding a dowel bar 8 on a column pile 14 at the corresponding elevation position, enabling the dowel bar 8 to pass through a slope sealing layer 11 and performing sealing treatment on the connection part of the dowel bar 8 and the slope sealing layer 11, then arranging an enclosing purlin 9 at the overhanging end of each dowel bar 8, and arranging a transverse strut 10 on the enclosing purlin 9, wherein the enclosing purlin 9 is required to be separated from the slope sealing layer 11, and the column pile 14, the dowel bar 8, the enclosing purlin 9 and the transverse strut 10 form an internal support system and form organic linkage with a vacuum support structure, so that sufficient safety guarantee is provided for vertical excavation of a deep foundation pit under the premise of no continuous pit wall curing wall;
Step S12, excavating a foundation pit according to the method in the step S10-step S11 until the foundation pit is excavated to the maximum pit bottom 12, performing sedimentation monitoring on the existing building 2 in the whole process in the excavation process in the step S9-step S12, and when the foundation of the existing building 2 is greatly deformed, performing grouting operation on the grouting bag 3 to control sedimentation and horizontal deformation of the foundation of the surrounding environment and ensure the safety of the surrounding environment;
Step S13, setting a slope bottom vertical closed curtain 13 at the bottom slope foot of the foundation pit, and sealing and connecting the lower end edge of the slope surface closed layer 11 to the top of the slope bottom vertical closed curtain 13, wherein the top Gao Chengxu of the slope bottom vertical closed curtain 13 is higher than the elevation of the maximum pit bottom 12;
S14, pouring a foundation pit bottom plate, and constructing a permanent structure of an underground part until the height of the permanent structure exceeds the pit top ground 1;
And S15, firstly removing and recovering the slope bottom vertical sealing curtain 13 along with the construction progress of the permanent structure, then removing and recovering the slope surface sealing layer 11 and each stage of inner supporting system step by step, backfilling the space between the pit wall of the foundation pit and the permanent structure of the underground part until reaching the elevation of the pit top ground 1, stopping vacuumizing, and then removing and recovering the horizontal sealing layer 5, the peripheral vertical sealing curtain 4 and the vertical reinforcement 16, thereby completing the foundation pit supporting and excavating work.
After the vacuum pressure source works, as the air and water in the original foundation soil are pumped away, the foundation soil becomes more compact, but the shrinkage deformation of the foundation soil also affects the peripheral soil, so that the peripheral soil has different degrees of shrinkage settlement, the shrinkage settlement can have adverse effect on the safety of the existing building 2, therefore, the effect needs to be reduced as much as possible in actual construction, the utility model improves the permanent strength of the soil outside the foundation pit through the vacuum consolidation effect, the effective stress of the soil caused by the negative pressure of the soil pores is increased, the temporary strength of the soil is improved, the strength of the permanent strength and the temporary strength is improved, the soil with the reinforced properties is tightly combined with the vertical reinforcement 16 to form a vertical reinforcement, the self stability of the side wall of the foundation pit can be greatly improved, and meanwhile, the inner support system is organically combined on the premise of not damaging the slope sealing layer 11, the stability of the pit wall is ensured under the synergistic effect of the self-stability of the enhanced soil body and the supporting force provided by the internal supporting system, the non-sloping excavation and the vertical excavation without the underground continuous wall with the excavation depth exceeding 10m are supported, the method has obvious cost advantages and construction period advantages compared with the supporting mode of the bored pile or the underground continuous wall and the internal supporting, the vacuum pumping and slope sealing layer 11 also has the functions of water stopping and precipitation, no extra water stopping and precipitation measures are needed, meanwhile, the arrangement of the vertical reinforcement 16 and the pile carrier 6 can effectively counteract the inward shrinkage deformation of the soil body outside the foundation pit caused by the vacuum action, the influence of the foundation pit vacuum supporting and excavation process on the adjacent existing building 2 is prevented, the arrangement of the grouting bag 3 can be used as a further insurance measure, when the foundation of the peripheral existing building 2 is greatly deformed, grouting operation is performed on the grouting bag 3 in time so as to control settlement and horizontal deformation of the foundation in the surrounding environment, and the safety of the surrounding environment is ensured.
The foundation pit engineering original supporting scheme is to support with bored piles, concrete ring beams and crowns Liang Jiana, and support with cement-soil mixing piles for water stop, the total cost is 1,680 ten thousand yuan, the construction period is 10 months, the cost of the foundation pit engineering original supporting scheme is 980 ten thousand yuan, and the construction period is 5 months, so that the cost is reduced by nearly one time, and the construction period is shortened by half, so that the economic benefit is very remarkable.
The foregoing description of the preferred embodiments of the utility model is not intended to limit the utility model to the precise form disclosed, and any such modifications, equivalents, and alternatives falling within the spirit and scope of the utility model are intended to be included within the scope of the utility model.
Claims (7)
1. A near deep basal pit vacuum supporting construction of existing building, its characterized in that: including horizontal drainage body (7) that set up in the foundation ditch edge outside certain limit, interval has set up vertical drainage body (15) and vertical reinforcement body (16) in the soil body of horizontal drainage body (7) below, vertical drainage body (15) and vertical reinforcement body (16) evenly arrange in the setting of horizontal drainage body (7) within range, and both bottom elevations are less than the maximum pit bottom (12) elevations of foundation ditch, the top elevation of vertical drainage body (15) is higher than foundation ditch outside ground (1) elevations and inserts in horizontal drainage body (7) and communicate with horizontal drainage body (7), horizontal drainage body (7) top is sealed through horizontal airtight layer (5), and horizontal drainage body (7) link to each other with the vacuum drainage system, be provided with peripheral vertical airtight curtain (4) in the soil body of horizontal airtight layer (5) outward flange position, and horizontal airtight layer (5) are connected with peripheral vertical airtight curtain (4) top seal, and horizontal airtight layer (5) are formed and are laid in the slope of foundation ditch edge position slope face downwardly in the formation and are covered in airtight layer (11), and airtight pit bottom (11) are connected to airtight pit bottom (13).
2. The deep foundation pit vacuum supporting structure adjacent to an existing building according to claim 1, wherein: the foundation pit is characterized by further comprising upright posts (14) arranged in soil body on the inner side of the pit wall of the foundation pit, wherein the upright posts (14) are arranged along the edge of the foundation pit at intervals, and the upright posts (14) are arranged close to the excavation surface.
3. The deep foundation pit vacuum supporting structure adjacent to an existing building according to claim 2, wherein: the slope surface airtight layer (11) is provided with enclosing purlin (9) and stull (10) near one side in the foundation ditch, enclosing purlin (9) are fixed on upright post (14) through dowel steel (8) and separate with slope surface airtight layer (11), dowel steel (8) one end and enclosing purlin (9) are fixed continuous, and the other end runs through slope surface airtight layer (11) and slope surface airtight layer (11) inboard soil body and upright post (14) fixedly continuous, and dowel steel (8) are sealed with slope surface airtight layer (11) seam crossing, stull (10) are fixed on enclosing purlin (9), dowel steel (8), enclosing purlin (9) and stull (10) form foundation ditch internal support system, and dowel steel (8), enclosing purlin (9) and stull (10) all set up in the foundation ditch with same vertical interval.
4. The deep foundation pit vacuum supporting structure adjacent to an existing building according to claim 1, wherein: grouting bags (3) are buried in soil bodies between the peripheral vertical airtight curtains (4) and the existing building (2).
5. The deep foundation pit vacuum supporting structure adjacent to an existing building according to claim 1, wherein: the pile carrier (6) is arranged at the top of the horizontal airtight layer (5), and the pile carrier (6) needs to be removed before the foundation pit is excavated.
6. The deep foundation pit vacuum supporting structure adjacent to an existing building according to claim 1, wherein: the vertical drainage bodies (15) and the vertical reinforcement bodies (16) are distributed according to a rectangular array or a triangular array.
7. A deep foundation pit vacuum supporting structure adjacent to an existing building as set forth in claim 3, wherein: the vertical reinforcement body (16) is made of screw steel, the upright post pile (14), the enclosing purlin (9) and the transverse brace (10) are made of H-shaped steel, and the dowel bar (8) is made of steel pipes.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202322573136.9U CN221001034U (en) | 2023-09-21 | 2023-09-21 | Vacuum supporting structure of deep foundation pit close to existing building |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202322573136.9U CN221001034U (en) | 2023-09-21 | 2023-09-21 | Vacuum supporting structure of deep foundation pit close to existing building |
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| CN221001034U true CN221001034U (en) | 2024-05-24 |
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| CN202322573136.9U Active CN221001034U (en) | 2023-09-21 | 2023-09-21 | Vacuum supporting structure of deep foundation pit close to existing building |
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