CN210658410U - Inverted wall hanging surrounding well structure - Google Patents
Inverted wall hanging surrounding well structure Download PDFInfo
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- CN210658410U CN210658410U CN201920973733.1U CN201920973733U CN210658410U CN 210658410 U CN210658410 U CN 210658410U CN 201920973733 U CN201920973733 U CN 201920973733U CN 210658410 U CN210658410 U CN 210658410U
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Abstract
The utility model relates to an inverted wall encloses well structure belongs to exploration construction technical field. The utility model discloses to the not ideal not enough of conventional exploration technique to deep sand bed sample disturbance influence big, sample small quantity and field test condition, provide an inverted wall enclosure structure, including the ground, the ground structure presss from both sides relative impervious sand bed for the overburden, still includes inverted wall and grout curtain, and the inverted wall adopts reinforced concrete structure, forms closed enclosure all around, and the inverted wall is from overburden upper portionThe wall body is arranged from top to bottom, and the thickness of the wall body is increased along with the increase of the depth; the grouting curtain is arranged on the periphery of the inverted wall to form a closed impervious curtain, and the grouting curtain is inserted into or penetrates through the relatively impervious sand layer. The relatively impervious sand layer usually has a buried depth of more than 30m, a thickness of more than 10m and a permeability coefficient of less than 10‑5cm/s. The inside of the surrounding well is supported by horizontal steel supports, a ground surface ring beam is poured at the top of the surrounding well, and a precipitation well is arranged at the bottom of the surrounding well.
Description
Technical Field
The utility model relates to an inverted wall encloses well structure belongs to exploration construction technical field.
Background
The traditional exploration method mainly takes exploration such as drilling and shallow shaft exploration, and limited tests such as side pressure test, penetration test and earthquake longitudinal and transverse wave test can be only carried out in field test. The drilling is an exploration method for detecting the thickness of a gravel layer, which can take core to identify the geological structure, divide the boundary line of the stratum, and simultaneously carry out hydrogeological test, comprehensive well logging and in-hole camera shooting operation to find the permeability characteristic of the stratum and more intuitively describe the geological characteristics in the hole; the existing drilling technology can realize covering layer drilling with the depth of more than 500 meters, but because the drill bit is smaller, the drilling sampling quantity is less, the disturbance influence on the soil sample is large, and the influence is more obvious along with the increase of the drilling depth; on the other hand, after a certain depth, for example, 50m, the difficulty of in-situ in-hole testing is increased, and the testing method and the evaluation standard need to be deeply researched. The depth of the shallow shaft is generally less than 10m, so that the prospecting personnel can directly observe the geological structure, and the method is accurate, reliable and convenient for sketch; from which pristine soil samples can be taken without restriction and used for large in situ testing.
The two water conservancy and hydropower engineering are widely applied to the covering layer exploration technology, and original state sampling and in-situ test of the deep covering layer are difficult to meet. For hydroelectric engineering in partial southwest region, the dam foundation covering layer is deep, the supporting layer mainly comprises fine particles, the physical and mechanical properties and the hydraulic properties of the covering layer, particularly the deep covering layer are found out, the relation between the mechanical properties and the burial depth of the covering layer is established, the problems of sedimentation deformation of the dam foundation covering layer, sandy soil liquefaction, stable sliding resistance, leakage, stable permeation and the like are accurately evaluated, structural calculation parameter indexes such as mechanical strength, bearing capacity, permeability, strong earthquake resistance, liquefaction resistance and the like of the dam foundation are provided, and the dam foundation is a key core foundation for dam engineering design.
SUMMERY OF THE UTILITY MODEL
The utility model discloses the technical problem that will solve is: aiming at the defects of large influence of conventional exploration technology on deep sand layer sampling disturbance, small sampling quantity and unsatisfactory field test conditions, the inverted wall surrounding well structure is provided.
For solving the technical problem the utility model discloses the technical scheme who adopts is: the inverted wall surrounding well structure comprises a foundation, an inverted wall and a grouting curtain, wherein the foundation structure is a covering layer with a relatively impervious sand layer, the inverted wall is of a reinforced concrete structure, a closed surrounding well is formed at the periphery, the inverted wall is arranged from top to bottom from the upper part of the covering layer, and the thickness of the wall body is increased along with the increase of the depth; the grouting curtain is arranged on the periphery of the inverted wall to form a closed impervious curtain, and the grouting curtain is inserted into or penetrates through the relatively impervious sand layer. The relatively impervious sand layer usually has a buried depth of more than 30m and a thickness of more than 10m, and permeatesCoefficient less than 10-5cm/s。
Further, the method comprises the following steps: the inverted wall hanging is a rectangular surrounding well surrounded by four walls, horizontal steel bars of adjacent wall bodies of the inverted wall hanging are mutually overlapped, vertical steel bars of upper and lower adjacent pouring layers are mutually overlapped, and the same layer of four wall bodies of the inverted wall hanging is an integral structure formed by integral pouring construction.
Further, the method comprises the following steps: the horizontal steel supports are arranged at four corners of the surrounding well from top to bottom in a layered mode, each layer of horizontal steel support is composed of four grouting steel pipes, each grouting steel pipe is welded to the embedded steel plates of the two adjacent wall bodies of the surrounding well, and the embedded steel plates are welded to the reinforcement cage of the wall body of the surrounding well through embedded steel bars.
Further, the method comprises the following steps: the grouting curtain forms a cylindrical impervious curtain, and the grouting curtain is arranged for a plurality of circles.
Further, the method comprises the following steps: and a ground surface ring beam is poured at the top of the surrounding well, and a dewatering well is arranged at the bottom of the surrounding well. And the ground surface ring beam is poured, so that water and other impurities above the ground can be prevented from falling into the well during the surrounding well excavation supporting construction. The dewatering well is set to provide dry land environment.
The inverted wall surrounding well structure can be implemented by the following steps: firstly, constructing a grouting curtain to form an anti-seepage curtain; and after the impervious curtain is finished and meets the design requirement, starting the surrounding well construction, wherein the surrounding well construction comprises covering layer excavation and inverted wall body pouring, the covering layer excavation and the inverted wall body pouring are alternately carried out, and a layer of excavation is carried out and a layer of pouring is carried out again until the excavation reaches the bottom of the well. When the bearing capacity of the covering layer does not meet the construction requirement, the foundation is firstly subjected to advanced consolidation grouting construction before the grouting curtain construction is carried out. After the grouting curtain construction is finished, grouting quality detection can be carried out by means of drilling water-pressing tests, sound wave tests and the like.
The bottom hole elevation is determined according to the comprehensive demonstration of the thickness, the mechanics and the permeability of the relative impervious sand layer and is generally arranged at the upper part of the relative impervious sand layer.
The inverted wall is preferably a rectangular surrounding well formed by four walls, the walls are of cast-in-place reinforced concrete structures, horizontal steel bars of two adjacent walls are mutually overlapped at corner positions, vertical steel bars of an upper wall poured in layers are required to extend into a lower layer, and the walls at four sides are poured simultaneously to form a whole.
When digging in the surrounding well formed by the inverted hanging wall body, the supporting is timely carried out, the preferable embodiment is that the inner wall of the surrounding well is provided with horizontal steel supports, the horizontal steel supports are arranged at four corners of the surrounding well in a layering mode from top to bottom, each layer of horizontal steel support is composed of four grouting steel pipes, each grouting steel pipe is welded on embedded steel plates of two adjacent wall bodies of the surrounding well, and the embedded steel plates are welded on a reinforcement cage of the wall body of the surrounding well through embedded steel bars.
During the construction of the surrounding well, the method specifically comprises the following steps:
d. the covering layer in the surrounding well is manually excavated and layered, constructors can go in and out and slag can be hoisted by using a gantry crane, and meanwhile, an emergency safety crawling ladder is arranged on the wall of the surrounding well;
e. cleaning the working surface of the excavation gap according to the requirements of field tests and soil sample extraction, and draining accumulated water;
f. after a layer of covering layer in the surrounding well is excavated, pouring a hanging wall; after the inverted wall of the layer reaches the design strength and installation conditions are provided in the surrounding well, the horizontal steel support is welded and installed on the embedded steel plate, and grouting and filling are carried out on the horizontal steel support;
g. d-f, circulating the working procedures, and performing the surrounding well lower soil excavation operation after the poured upper wall concrete reaches the design strength during excavation; until the well bottom is excavated, and a dewatering well is arranged at the well bottom.
For guaranteeing the construction safety, the utility model discloses still include following step:
safety monitoring is carried out in the excavation process: during the construction and excavation of the surrounding well, a movable inclinometer and a flat water level gauge are adopted to monitor the deflection deformation and seepage of the surrounding well; selecting a monitoring section in a region close to the bottom of the surrounding well, wherein the monitoring section comprises a horizontal steel support, and arranging a reinforcing steel bar meter on an embedded reinforcing steel bar at each connecting part of the horizontal steel support and the inverted wall of the monitoring section to monitor the stress of the reinforcing steel bar;
and (4) according to the safety monitoring result of the working procedures, carrying out inverted wall deformation and in-well seepage rechecking, and taking safety construction measures if necessary.
The utility model has the advantages that: the grouting curtain extends into or penetrates through the relatively impervious sand layer to provide safety guarantee for the construction of the inverted hanging wall surrounding well; the inverted wall body with the reinforced concrete structure is integrally cast, the reinforcing steel bars of the adjacent wall bodies are mutually lapped, and the integral stability of the surrounding well is further enhanced by welding the horizontal steel supports; the bottom of the enclosing well is a relatively impervious sand layer, and a dewatering well is arranged in an excavating foundation pit of the enclosing well to provide a dry land operation environment.
Drawings
Fig. 1 is a schematic cross-sectional view of the present invention.
3 fig. 3 2 3 is 3 a 3 schematic 3 view 3 a 3- 3 a 3 of 3 fig. 3 1 3. 3
Parts in the figure are marked: the water-proof sand-filled water-proof sand-proof water-proof sand.
Detailed Description
The present invention will be further explained with reference to the drawings and the embodiments.
As shown in fig. 1 and 2, the foundation structure of the present invention is a covering layer 1 with a relatively impervious sand layer 2 sandwiched therebetween, and further includes an inverted wall 3 and a grouting curtain 7, wherein the inverted wall 3 is of a reinforced concrete structure and forms a closed type surrounding well all around, and the inverted wall 3 is arranged from the upper portion of the covering layer 1 to the lower portion from the top and increases the wall thickness with the increase of depth; a grouting curtain 7 is provided at the outer periphery of the inverted wall 3 to form a closed impervious curtain, and the grouting curtain 7 is inserted into or passes through the relatively impervious sand layer 2. The relatively impervious sand layer 2 is buried in depth of more than 30m, thickness of more than 10m and permeability coefficient of less than 10-5cm/s. When in implementation, the construction of the grouting curtain 7 is firstly carried out to form an anti-seepage curtain; after the impervious curtain is finished and the design requirement is met, starting the surrounding well construction, wherein the surrounding well construction comprises the excavation of a covering layer 1 and the pouring of a wall body of an inverted wall 3, the excavation and the pouring are alternately carried out, a layer is excavated and then a layer is poured until the bottom of the well 9 is excavated, and a dewatering well 8 is arranged at the bottom of the well 9. The grouting curtain 7 is preferably formed as a cylindrical impervious curtain, the grouting curtain 7 may be provided in a plurality of turns, and the depth of the grouting curtain 7The degree and the number of rows should be determined by calculation based on the seepage. The height of the well bottom 9 is determined according to the comprehensive demonstration of the thickness, the mechanics and the permeability of the relative impervious sand layer 2 and is generally arranged at the upper part of the relative impervious sand layer 2. Whether the lower end of the grouting curtain 7 is inserted into or penetrated through the relatively impermeable sand layer 2 should also be determined according to comprehensive demonstration of thickness, mechanics and permeability of the relatively impermeable sand layer 2.
During construction, the grouting curtain 7 adopts orifice sealing and is grouted from top to bottom; when the bearing capacity of the covering layer 1 on the ground surface does not meet the construction requirement, necessary foundation advanced consolidation grouting construction is required before grouting curtain 7 construction. After the grouting curtain 7 is constructed, grouting quality detection can be performed by means of a drilling water-pressure test, a sound wave test and the like.
For convenient construction and stable structure, the inverted wall 3 is a rectangular surrounding well surrounded by four walls, horizontal steel bars of adjacent walls of the inverted wall 3 are mutually overlapped, vertical steel bars of upper and lower adjacent pouring layers are mutually overlapped, and the wall on the same layer of the inverted wall 3 is of an integral structure formed by integral pouring construction.
When excavating in the enclosing well formed by the inverted hanging wall 3, the supporting is carried out in time, the preferred embodiment is that the inner wall of the enclosing well is provided with horizontal steel supports 6, the horizontal steel supports 6 are arranged at four corners of the enclosing well from top to bottom in a layered mode, each layer of horizontal steel support 6 is composed of four grouting steel pipes, each grouting steel pipe is welded on the embedded steel plates 5 of the two adjacent walls of the enclosing well, and the embedded steel plates 5 are welded on the reinforcement cage of the enclosing well wall through embedded steel bars 4.
The support type, the support time and the support parameter design adopted in the surrounding well formed by excavation are determined by comprehensive technical and economic demonstration analysis.
In addition, a ground surface ring beam 10 is poured on the top of the inverted hanging wall 3, and a dewatering well 8 is arranged at the bottom hole 9 of the surrounding well. The ground surface ring beam 10 is poured, so that water and other impurities above the ground 11 can be prevented from falling into the well during the surrounding well excavation supporting construction. The dewatering well 8 is provided for the purpose of providing a dry working environment.
The utility model discloses it is preferred to implement according to following step:
a. constructing a grouting curtain 7; drilling equipment and a construction mode are selected according to the characteristics of the covering layer 1 and the relatively impervious sand layer 2;
b. after the construction of the grouting curtain 7 is finished, grouting quality detection is carried out by means of a drilling water-pressing test, a sound wave test and the like; after the grouting curtain 7 meets the design requirements, carrying out the surrounding well construction;
c. when the first layer of inverted wall hanging 3 is poured, the ground surface ring beam 10 is poured at the top, so that water and other impurities above the ground 11 are prevented from falling into the well when the surrounding well excavation supporting construction is carried out;
d. the covering layer 1 in the surrounding well is manually excavated and layered, constructors can go in and out and slag can be hoisted by using a gantry crane, and meanwhile, an emergency safety crawling ladder is arranged on the wall of the surrounding well;
e. cleaning the working surface of the excavation gap according to the requirements of field tests and soil sample extraction, and draining accumulated water;
f. after one layer of covering layer 1 in the surrounding well is excavated, pouring a hanging wall 3; after the inverted hanging wall 3 of the layer reaches the design strength and installation conditions are provided in the surrounding well, the horizontal steel support 6 is welded and installed on the embedded steel plate 5, and the horizontal steel support 6 is grouted and filled;
g. d-f, circulating the working procedures, and performing the surrounding well lower soil excavation operation after the poured upper wall concrete reaches the design strength during excavation; until the well bottom 9 is excavated, and a dewatering well 8 is arranged at the well bottom 9;
h. safety monitoring is carried out in the excavation process: during the construction and excavation of the surrounding well, a movable inclinometer and a flat water level gauge are adopted to monitor the deflection deformation and seepage of the surrounding well; selecting a monitoring section in a region close to the bottom of the surrounding well, wherein the monitoring section comprises a horizontal steel support 6, and arranging a steel bar meter on the embedded steel bar 4 at each connecting part of the horizontal steel support 6 and the inverted hanging wall 3 of the monitoring section to monitor the steel bar stress of the monitoring section; in specific implementation, 2 monitoring sections can be selected in an area close to the bottom with larger stress, the monitoring frequency is 1 week and 1 time, and meanwhile, field inspection is carried out;
i. and (4) according to the safety monitoring result of the procedure h, performing deformation of the hanging wall 3 and rechecking of seepage in the well, and taking safety construction measures if necessary.
Example (b):
the depth of the covering layer 1 exceeds 100m, a relatively impermeable sand layer 2 is sandwiched between the covering layer and the relatively impermeable sand layer 2, the buried depth of the relatively impermeable sand layer 2 is about 50m, the thickness is 15 m-20 m, and the permeability coefficient is 10-5cm/s～10-6cm/s. In order to clear up the mechanical and seepage characteristics of the covering layer 1 and the relatively impervious sand layer 2, an inverted wall surrounding well structure is adopted to carry out original sampling and in-situ test on the covering layer 1 and the relatively impervious sand layer 2. The inverted wall 3 is made of reinforced concrete and has a wall thickness of 0.6-1.0 m. The net size of the plane of the surrounding well is 6.4m multiplied by 6.4m, the well depth is 56m, and the well bottom is positioned at the upper part of the relatively impervious sand layer 2. And (3) adopting a cylindrical grouting curtain 7 for seepage prevention around the surrounding well, wherein the grouting curtain 7 penetrates through the relatively impervious sand layer 2 and is inserted into the lower covering layer 1 to the depth of 20m through seepage calculation, the grouting curtain 7 is provided with 3 rows of grouting holes, the plane radiuses of the 3 rows of grouting curtains are respectively 6.44m, 7.04m and 7.64 m. In order to ensure the stability of the structure of the wall-hung type 3 surrounding well, 20 layers of horizontal steel supports 6 are arranged on the inner wall of the wall-hung type 3 surrounding well, and through structural calculation, one layer of the horizontal steel supports 6 is arranged at intervals of 2-5 m in height, wherein the upper part of the wall-hung type 3 is under small stress, the interlayer interval is large, the lower part of the wall-hung type is under large stress, and the interlayer interval is small. Each layer of horizontal steel support 6 comprises four steel pipes with the diameter of 600mm, the steel pipes are respectively and obliquely supported on the wall bodies of the adjacent two inverted wall hanging bodies 3, and C35 expanded cement mortar is poured into the steel pipes; the wall built-in connection method comprises the following steps that an embedded steel plate 5 with the thickness of 30mm and a U-shaped anchoring embedded steel bar 4 welded on the steel plate are embedded in a supporting section of the wall built-in connection wall 3, and the embedded steel bar 4 and the embedded steel plate 5 are welded on a steel bar cage in the wall built-in connection wall 3 and poured in concrete. In order to ensure the overall stability of the wall body 3 of the inverted wall, the wall body 3 of the inverted wall is integrally cast in a surrounding well, horizontal steel bars of adjacent wall bodies are mutually lapped, and vertical steel bars of upper and lower adjacent casting layers are mutually lapped.
Claims (6)
1. Inverted hanging wall encloses well structure, including the ground, ground structure presss from both sides relative impervious sand bed (2), its characterized in that for overburden (1): the wall-hung type water-cooled underground mining well is characterized by further comprising a wall-hung type (3) and a grouting curtain (7), wherein the wall-hung type (3) is of a reinforced concrete structure, a closed type surrounding well is formed around the wall-hung type (3), the wall-hung type (3) is arranged from top to bottom on the upper portion of the covering layer (1), and the thickness of the wall body is increased along with the increase of the depth; the grouting curtain (7) is arranged on the periphery of the inverted wall (3) to form a closed impervious curtain, and the grouting curtain (7) is inserted into or penetrates through the relatively impervious sand layer (2).
2. The inverted walled well structure of claim 1, wherein: the wall hanging type inverted wall (3) is a rectangular surrounding well formed by surrounding four walls, horizontal steel bars of adjacent wall bodies of the wall hanging type inverted wall (3) are mutually lapped, vertical steel bars of upper and lower adjacent pouring layers are mutually lapped, and the wall bodies of the same layer of the wall hanging type inverted wall (3) are of an integrated structure formed by integral pouring construction.
3. The inverted walled well structure of claim 2, wherein: the horizontal steel supports (6) are arranged at four corners of the surrounding well from top to bottom in a layered mode, each layer of horizontal steel support (6) is composed of four grouting steel pipes, each grouting steel pipe is welded to embedded steel plates (5) of two adjacent wall bodies of the surrounding well, and the embedded steel plates (5) are welded to a reinforcement cage of the wall body of the surrounding well through embedded steel bars (4).
4. The inverted walled well structure of claim 1, wherein: the grouting curtain (7) forms a cylindrical impervious curtain, and the grouting curtain (7) is provided with a plurality of circles.
5. The inverted walled well structure of claim 1, wherein: the top of the surrounding well is poured with a ground surface ring beam (10), and a precipitation well (8) is arranged at the bottom of the surrounding well (9).
6. An inverted walled well structure according to any one of claims 1 to 5 wherein: the bottom (9) of the enclosed well is arranged at the upper part of the sand layer (2) which is relatively impervious to water.
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| CN201920973733.1U CN210658410U (en) | 2019-06-26 | 2019-06-26 | Inverted wall hanging surrounding well structure |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110258606A (en) * | 2019-06-26 | 2019-09-20 | 中国电建集团成都勘测设计研究院有限公司 | Projecting wall encloses well construction |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110258606A (en) * | 2019-06-26 | 2019-09-20 | 中国电建集团成都勘测设计研究院有限公司 | Projecting wall encloses well construction |
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