CN210684356U - Composite embankment structure of large-diameter steel corrugated pipe and foamed light soil - Google Patents
Composite embankment structure of large-diameter steel corrugated pipe and foamed light soil Download PDFInfo
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- CN210684356U CN210684356U CN201921221444.2U CN201921221444U CN210684356U CN 210684356 U CN210684356 U CN 210684356U CN 201921221444 U CN201921221444 U CN 201921221444U CN 210684356 U CN210684356 U CN 210684356U
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Abstract
The utility model provides a compound embankment structure of major diameter corrugated steel pipe and foam light soil belongs to embankment technical field. The structure comprises a sand cushion layer, large-diameter steel corrugated pipes, foamed lightweight soil and a pavement structure layer from bottom to top, wherein the sand cushion layer is positioned at the bottom layer of an embankment, a plurality of transverse large-diameter steel corrugated pipes are arranged on the sand cushion layer along the direction of a road, and gaps among the large-diameter steel corrugated pipes and the top of the pipes are backfilled with the foamed lightweight soil; every tube coupling of major diameter corrugated steel pipe is formed by a plurality of corrugated segments concatenation, and the junction bolt uses the wrench twist to decide to twist to the regulation moment of torsion, passes through loop formula flange, seal gasket and bolt fastening between tube coupling and the tube coupling. The structure utilizes the characteristics of convenient transportation, simple construction, small dead weight, high bearing capacity, short construction period and the like of the steel corrugated pipe, fills the embankment by using the large-diameter corrugated pipe, avoids and reduces the occurrence of diseases in the operation process, improves the travelling comfort, reduces the cost of later-stage maintenance and repair, and realizes the optimal cost of the whole life cycle.
Description
Technical Field
The utility model relates to an embankment technical field especially indicates a compound embankment structure of major diameter corrugated steel pipe and foam light soil.
Background
When a highway is built in a city in the south-east coast, the highway is often influenced by a deep soft soil foundation. Due to the fact that a large amount of deep soft soil is distributed under the ground surface, the deep soft soil is large in pore ratio, high in water content, large in compressibility, high in sensitivity, low in strength and low in consolidation coefficient, the post-construction settlement and differential settlement of the highway are large, and quality defects such as bridge head bumping, pavement damage and the like are caused.
At present, the treatment of soft soil foundation mainly comprises drainage consolidation, composite foundation, pipe pile and other methods in China, which are conventional soft foundation treatment methods, and the method has long construction period, high cost and difficult control of post-construction settlement when treating deep soft soil foundation. Consider corrugated steel pipe characteristics such as transportation of being convenient for, construction are simple, the dead weight is little, bear the weight of dynamic height, time limit for a project weak point, the utility model provides a major diameter corrugated steel pipe adopts upper portion deloading method with the compound embankment structure of foam light soil, on the basis of conventional weak soil roadbed processing, reduces the post-construction settlement by a wide margin through lightening embankment load. On the aspect of ensuring the soft soil foundation treatment effect, the occurrence of diseases in the operation process is avoided and reduced, the driving comfort is improved, the cost of later-stage maintenance and repair is reduced, and the optimal cost of the whole life cycle is realized.
SUMMERY OF THE UTILITY MODEL
The to-be-solved technical problem of the utility model is to provide a compound embankment structure of major diameter corrugated steel pipe and foam light soil.
The structure comprises a sand cushion layer, a large-diameter steel corrugated pipe, a light filling material and a pavement structure layer which are distributed from bottom to top; the sand cushion layer is positioned at the bottom layer of the embankment; a plurality of transverse large-diameter steel corrugated pipes are arranged on the sand cushion layer along the line direction; gaps among the large-diameter steel corrugated pipes and the top of the large-diameter steel corrugated pipes are backfilled by using a light filling material.
Wherein:
the sand cushion layer is compacted in a layered mode by adopting clean medium coarse sand, the end portion of the sand cushion layer is wrapped by adopting reverse filter geotextile, and the maximum grain size of the used medium coarse sand is 8 mm.
The large-diameter steel corrugated pipe consists of a plurality of steel corrugated pipe sections, two adjacent steel corrugated pipe sections are fixed through an inner angle steel flange, a sealing gasket, an outer angle steel flange, bolts and nuts, wherein the inner angle steel flange and the outer angle steel flange are respectively positioned inside and outside the two adjacent steel corrugated pipe sections, the sealing gasket is positioned between contact surfaces of the two adjacent steel corrugated pipe sections, and a plurality of bolts and nuts are uniformly distributed on the outer angle steel flange; each steel corrugated pipe section is formed by splicing a plurality of corrugated pipe pieces.
The bolt and the nut are screwed to a specified torque by using a fixed-torque wrench, and the torque of each nut is not less than 135.6 N.m and not more than 203.4 N.m at most.
The gaps among the large-diameter steel corrugated pipes are subjected to layered pouring by using a light filling material, wherein the light filling material comprises foamed light soil and fly ash, and preferably the foamed light soil; and the top of the large-diameter steel corrugated pipe is poured in a layered mode by adopting foamed light soil.
Protective structures are arranged at two ends of the large-diameter steel corrugated pipe and comprise a straight wall, a slope and a splayed wall, and the protective structures are specifically selected according to actual conditions of a field.
The inside of the large-diameter steel corrugated pipe is provided with a solid structure and a hollow structure, and the hollow structure is used for a scene that an embankment needs to be managed and flooded; the solid structure is used in the scene that the embankment does not need to be managed and contained with water; the inner filling and the two end seals of the solid structure are both made of light filling materials.
The upper part of the foam light soil is built with a pavement structure layer which comprises a curb belt, a traffic lane and a road shoulder from inside to outside.
The utility model discloses an above-mentioned technical scheme's beneficial effect as follows:
the structure adopts the large-diameter steel corrugated pipe composite foam light soil to fill the embankment, and the light embankment can effectively reduce the pressure of embankment filling on a soft soil foundation by utilizing the characteristics of the light weight of the steel corrugated pipe and the foam light soil, thereby playing the effect of controlling the settlement after construction; the used large-diameter steel corrugated pipe has a circular shell structure and the arrangement of corrugations, so that the large-diameter steel corrugated pipe has a good stress effect, the bearing capacity of the embankment is improved, the deformation of the embankment is reduced, the occurrence of diseases in the operation process can be avoided and reduced, and the driving comfort is improved; the large-diameter steel corrugated pipe composite foam light soil is adopted to fill the embankment, and mainly comprises assembled pipe joints and pouring of foam light soil in construction, so that the construction period is short, and the time cost is greatly saved; the large-diameter steel corrugated pipe is used for filling the embankment, the embankment is convenient to update and maintain during operation, operation can be performed under the condition of not interrupting traffic, and the cost of later-period maintenance and repair is reduced.
Drawings
Fig. 1 is a schematic longitudinal section view of a composite embankment structure of a large-diameter steel corrugated pipe and foamed lightweight soil according to the present invention;
fig. 2 is a schematic cross-sectional view of the composite embankment structure of large-diameter corrugated steel pipe and foamed light soil according to the present invention;
fig. 3 is a schematic elevation view of the composite embankment structure of large-diameter corrugated steel pipe and foamed light soil according to the present invention;
FIG. 4 is a sectional view of a corrugated steel pipe coupling flange of the composite embankment structure of large-diameter corrugated steel pipe and foamed lightweight soil according to the present invention;
fig. 5 is a schematic structural view of a corrugated steel pipe flange of the composite embankment structure of large-diameter corrugated steel pipe and foamed lightweight soil according to the present invention;
fig. 6 is a schematic view of an elevation of an embankment slope-releasing treatment method of the composite embankment structure of the large-diameter corrugated steel pipe and the foamed light soil according to the present invention.
Wherein: 1-pavement structure layer, 2-foam light soil, 3-large-diameter steel corrugated pipe, 4-straight wall, 5-sand cushion layer, 6-conventional roadbed filling, 7-steel corrugated pipe joint, 8-internal angle steel flange, 9-sealing gasket, 10-external angle steel flange, 11-bolt, 12-nut, 13-foundation and 14-light filling material.
Detailed Description
In order to make the technical problems, technical solutions and advantages to be solved by the present invention clearer, the following detailed description will be given with reference to the accompanying drawings and specific embodiments.
The utility model provides a compound embankment structure of major diameter corrugated steel pipe and foam light soil.
As shown in fig. 1, 2, 3 and 6, the structure comprises a sand cushion layer 5, a large-diameter steel corrugated pipe 3, a light filling material (preferably foamed light soil 2 here) and a pavement structure layer 1 which are distributed from bottom to top; the sand cushion layer 5 is positioned at the bottom layer of the embankment; a plurality of transverse large-diameter steel corrugated pipes 3 are arranged on the sand cushion layer 5 along the line direction; gaps among the large-diameter steel corrugated pipes 3 and the top of the pipes are backfilled by foamed lightweight soil 2.
Wherein:
the sand cushion layer 5 is compacted by clean medium coarse sand in a layered mode, and the end portion of the sand cushion layer is wrapped by reverse filter geotextile.
As shown in fig. 4 and 5, the large-diameter corrugated steel pipe 3 is composed of a plurality of corrugated steel pipe sections 7, two adjacent corrugated steel pipe sections are fixed by an inner angle steel flange 8, a sealing gasket 9, an outer angle steel flange 10, bolts 11 and nuts 12, wherein the inner angle steel flange 8 and the outer angle steel flange 10 are respectively positioned inside and outside the two adjacent corrugated steel pipe sections 7, the sealing gasket 9 is positioned between contact surfaces of the two adjacent corrugated steel pipe sections 7, and a plurality of bolts 11 and nuts 12 are uniformly distributed on the outer angle steel flange 10; each steel corrugated pipe section 7 is formed by splicing a plurality of corrugated pipe pieces.
The bolt 11 and the nut 12 are screwed to a prescribed torque using a fixed-torque wrench.
The gaps among the large-diameter steel corrugated pipes 3 are cast in layers by using a light filling material 14, wherein the light filling material 14 comprises foamed light soil 2 and fly ash, and the foamed light soil 2 is preferably selected; the top of the large-diameter steel corrugated pipe 3 is poured in layers by adopting foamed light soil 2.
3 both ends of major diameter corrugated steel pipe set up protective structure, and protective structure includes a word wall 4, puts slope, splayed wall, specifically selects protective structure according to place actual conditions.
The inside of the large-diameter steel corrugated pipe is provided with a solid structure and a hollow structure, and the hollow structure is used for a scene that an embankment needs to be managed and flooded; the solid structure is used in the scene that the embankment does not need to be managed and contained with water; the internal filling and the seals at both ends of the solid structure are light filling materials 14.
The upper part of the foam light soil 2 is built with a pavement structure layer 1, and the pavement structure layer 1 comprises a curb belt, a traffic lane and a road shoulder from inside to outside.
The preferred embodiment of the utility model is as follows:
as shown in fig. 1, 2 and 3, the structure is placed on a foundation 13 and comprises a sand cushion layer 5, a large-diameter steel corrugated pipe 3, foamed lightweight soil 2 and a pavement structure layer 1 from bottom to top. The bottom layer of the embankment is a sand cushion layer 5; the sand cushion layer 5 is compacted by clean medium coarse sand layers in a layering mode, and the end portion of the sand cushion layer is wrapped by reverse filter geotextile. A plurality of large-diameter steel corrugated pipes 3 are horizontally arranged on the sand cushion layer 5 along the line direction; each steel corrugated pipe joint 7 of the large-diameter steel corrugated pipe 3 is formed by splicing a plurality of corrugated pipe pieces, and a bolt 11 at the joint is screwed to a specified torque by using a fixed-torque wrench; the pipe joints are fixed by an inner angle steel flange 8, an outer angle steel flange 10, a sealing gasket 9 and a bolt 11. Pouring gaps among the large-diameter steel corrugated pipes 3 and the top of the large-diameter steel corrugated pipes in a layered mode by using foamed light soil 2, wherein the single-layer pouring thickness is 0.5 m; the inside of the large-diameter steel corrugated pipe 3 can be filled with a light material 14; a straight wall 4 is arranged at the end part of the large-diameter steel corrugated pipe 3 for blocking and protecting. The pavement structure layer 1 comprises a curb belt, a traffic lane and a road shoulder from inside to outside, and the gradient of the road shoulder is 1: 1.5.
The implementation process of the structure is as follows:
first, construction lofting
Before construction, the center and the longitudinal and transverse axes of the large-diameter steel corrugated pipe 3 are accurately determined in the conventional roadbed filling 6. And (5) discharging the width of the sand cushion layer, and replacing the side widening pile with a 50cm wide side, and discharging the pile to be large enough at one time.
Second, sand cushion layer construction
The thickness of the sand cushion layer 5 is designed to be 35cm, and clean medium and coarse sand is adopted. When the sand cushion layer 5 is filled, the sand cushion layer is compacted in a layering mode, the compaction thickness of each layer is 10 cm-20 cm, the sand cushion layer is temporarily protected in a proper mode so as to prevent sand from losing, and the thickness is increased by 30cm within the range of 1m of a slope toe. The bottom of the sand mats 5 in the adjacent treatment zones should in principle be substantially uniform in the longitudinal direction of the course and remain smooth. The end part of the sand cushion layer 5 adopts a reverse filter geotextile wrapping.
Construction of three-layer integral large-diameter steel corrugated pipe
1. And (5) checking the flatness, elevation and foundation pre-camber of the foundation at the bottom of the pipe, and determining the position, central axis and midpoint of the culvert.
2. According to the actual situation, the discharge pipe. When the pipe joint is installed, a first pipe joint is arranged from one side, the center of the pipe joint is enabled to be parallel to the longitudinal center line of a foundation, a second pipe joint is placed in place, when the distance between two adjacent flanges of the two pipes is a gap of 3-5 cm, a small crowbar is aligned to bolt holes in the flanges, bolts on the two pipe flanges are aligned, at the moment, the pipe joint is pried by a crowbar from the other end of the second pipe joint, the pipe joint is enabled to longitudinally translate towards a culvert, when the distance between the two flanges is about 2cm, each bolt is inserted into the bolt hole, and after the nut is sleeved, the bolt is slightly screwed, and the nut is not screwed.
3. Due to the reasons of field topography and the like, the distance between two adjacent flanges is small sometimes, a gap of about 1cm is chiseled between the two flanges by a hand hammer and a chisel, the sealing gasket is inlaid between the two flanges by a screwdriver, sometimes, the distance between the two flanges at the top of the pipe joint is large, the sealing gasket is difficult to inlay, the sealing gasket is tied on a bolt by a tying wire for fixing, and then a worker starts to symmetrically screw the screw cap. Until only a gap of 2-5 mm is formed between the two flanges in the appearance.
4. And after all the components are assembled, the nuts are screwed one by one. The torque of each nut is not less than 135.6 N.m, and not more than 203.4 N.m at most. When a mechanical wrench is used, the twisting and pulling time lasts for 2-5 s. And thereafter connected in sequence in this manner.
5. And (5) correcting the whole pipe by using a jack to enable the center of the whole pipe to be located on the central axis of the pipe position.
Backfilling two sides and top of steel corrugated pipe
1. And the two sides and the top are backfilled by adopting foamed light soil 2, and the backfilling thickness is controlled to be 50cm above the top of the pipe.
2. The wedge-shaped part of the large-diameter steel corrugated pipe is backfilled by gravel with good gradation, and is tamped by a small-sized tamping machine. Within 0.5m close to the periphery of the pipe body, hard objects such as stones larger than 50mm are not allowed.
3. The backfill of the upper part and two side parts of the top of the large-diameter steel corrugated pipe 3 must be symmetrically and synchronously carried out at two sides of the pipe, the height difference of backfill materials at the two sides is not more than 15cm, and baffles are arranged at the two sides of the pipe, so that the backfill is carried out from the two ends of the pipe to the center of the structure.
Fifthly, pouring the foam light soil
1. The division of the casting layer should be based on the single-layer casting thickness of 0.5 m. Pouring of each layer is completed within the initial setting time of cement paste, and the pouring time is not more than 3 hours. The time interval from the completion of the preparation to the start of the preparation of the foamed lightweight soil 2 should not exceed 3 hours at maximum.
2. Pouring from one end to the other end along the long axis direction of the pouring area; if a plurality of pouring pipes are used for pouring, pouring can be started from one end side by side or a diagonal pouring mode is adopted. In the pouring process, the height difference between a discharge port of the pouring tube and the current pouring surface is not more than 1m at most.
3. Deformation joints are arranged in the pouring length of the foamed light soil 3 according to the distance of 15m, the width of the joints is not smaller than 10mm, and the deformation joints of the upper and lower adjacent pouring layers are arranged in a staggered mode. The deformation joint gap filling material is preferably a foam plate, a wood template, an extruded plate and the like with the thickness of 15 mm.
The foregoing is a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of improvements and decorations can be made without departing from the principle of the present invention, and these improvements and decorations should also be regarded as the protection scope of the present invention.
Claims (8)
1. The utility model provides a compound embankment structure of major diameter corrugated steel pipe and foam light soil which characterized in that: comprises a sand cushion layer (5), a large-diameter steel corrugated pipe (3), a light filling material (14) and a pavement structure layer (1) which are distributed from bottom to top; the sand cushion layer (5) is positioned at the bottom layer of the embankment; at least three transverse large-diameter steel corrugated pipes (3) are arranged on the sand cushion layer (5) along the line direction; the gaps between the large-diameter steel corrugated pipes (3) and the top of the pipes are backfilled by using a light filling material (14).
2. The large-diameter corrugated steel pipe and foamed lightweight soil composite embankment structure according to claim 1, wherein: the sand cushion layer (5) is compacted in a layered mode by adopting clean medium coarse sand, the maximum grain diameter of the medium coarse sand is 8mm, and the end portion of the medium coarse sand is wrapped by adopting reverse-filtering geotextile.
3. The large-diameter corrugated steel pipe and foamed lightweight soil composite embankment structure according to claim 1, wherein: the large-diameter corrugated steel pipe (3) is composed of a plurality of corrugated steel pipe sections (7), two adjacent corrugated steel pipe sections (7) are fixed through an inner angle steel flange (8), a sealing gasket (9), an outer angle steel flange (10), bolts (11) and nuts (12), wherein the inner angle steel flange (8) and the outer angle steel flange (10) are respectively positioned inside and outside the two adjacent corrugated steel pipe sections (7), the sealing gasket (9) is positioned between contact surfaces of the two adjacent corrugated steel pipe sections (7), and at least three bolts (11) and nuts (12) are uniformly distributed on the outer angle steel flange (10); each steel corrugated pipe section (7) is formed by splicing more than three corrugated pipe pieces.
4. A large diameter corrugated steel tubing and foamed lightweight soil composite embankment structure according to claim 3, wherein: the bolt (11) and the nut (12) are screwed to a specified torque by using a fixed-torque wrench, and the torque of each nut is not less than 135.6 N.m and not more than 203.4 N.m at most.
5. The large-diameter corrugated steel pipe and foamed lightweight soil composite embankment structure according to claim 1, wherein: the light filling material (14) comprises foamed light soil (2) and fly ash, and the top of the large-diameter steel corrugated pipe (3) is poured in layers by adopting the foamed light soil (2).
6. The large-diameter corrugated steel pipe and foamed lightweight soil composite embankment structure according to claim 1, wherein: protective structures are arranged at two ends of the large-diameter steel corrugated pipe (3), each protective structure comprises a straight wall (4), a slope and a splayed wall, and the protective structures are specifically selected according to actual conditions of a field.
7. The large-diameter corrugated steel pipe and foamed lightweight soil composite embankment structure according to claim 1, wherein: the large-diameter steel corrugated pipe (3) is internally provided with a solid structure and a hollow structure, and the hollow structure is used in a scene that the embankment needs to be managed and flooded; the solid structure is used in the scene that the embankment does not need to be managed and contained with water; the internal filling and the two end seals of the solid structure are both light filling materials (14).
8. The large-diameter corrugated steel pipe and foamed lightweight soil composite embankment structure according to claim 1, wherein: the upper part of the light filling material (14) is built with a pavement structure layer (1), and the pavement structure layer (1) comprises a curb belt, a traffic lane and a road shoulder from inside to outside.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921221444.2U CN210684356U (en) | 2019-07-30 | 2019-07-30 | Composite embankment structure of large-diameter steel corrugated pipe and foamed light soil |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201921221444.2U CN210684356U (en) | 2019-07-30 | 2019-07-30 | Composite embankment structure of large-diameter steel corrugated pipe and foamed light soil |
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| CN210684356U true CN210684356U (en) | 2020-06-05 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110373968A (en) * | 2019-07-30 | 2019-10-25 | 中电建路桥集团有限公司 | A kind of compound embankment structure of Large-diameter Steel bellows and Foam lightweight soil |
-
2019
- 2019-07-30 CN CN201921221444.2U patent/CN210684356U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110373968A (en) * | 2019-07-30 | 2019-10-25 | 中电建路桥集团有限公司 | A kind of compound embankment structure of Large-diameter Steel bellows and Foam lightweight soil |
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