CN111042145B - Construction method for excavating foundation pit near deep-buried large-diameter pipeline - Google Patents
Construction method for excavating foundation pit near deep-buried large-diameter pipeline Download PDFInfo
- Publication number
- CN111042145B CN111042145B CN202010001188.7A CN202010001188A CN111042145B CN 111042145 B CN111042145 B CN 111042145B CN 202010001188 A CN202010001188 A CN 202010001188A CN 111042145 B CN111042145 B CN 111042145B
- Authority
- CN
- China
- Prior art keywords
- foundation pit
- layer
- earthwork
- pipeline
- excavating
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D17/00—Excavations; Bordering of excavations; Making embankments
- E02D17/02—Foundation pits
Abstract
The invention discloses a construction method for excavating a foundation pit close to a deeply buried large-diameter pipeline, which comprises the following steps of: and excavating foundation pit earthwork outside the affected area, excavating foundation pit earthwork in the affected area in a layered, segmented and segmented manner, and constructing a bottom plate. The invention has the advantage of safe construction when no active protection measures are taken on the pipeline.
Description
Technical Field
The invention relates to the field of excavation of foundation pits of subway stations, in particular to a construction method for excavating foundation pits close to deeply buried large-diameter pipelines.
Background
At present, underground piping is mostly combination formula prefabricated reinforced concrete structure, and the size is less, and structural strength is general, and self stability is relatively poor, and the safe risk is relatively, closes on the basement and buries subway station foundation ditch excavation construction on the major diameter pipeline deeply and has following difficult problem: (1) the pipeline is too close to the bottom of the foundation pit, and no safe construction distance exists; (2) part of pipelines are constructed by adopting socket joint type concrete pipes, so that the number of pipeline joints is large, and the leakage risk is high; (3) the pipeline is positioned in the foundation pit, the residual undisturbed soil on the upper part is less and thinner, and the pipeline is easy to deform and crack by adopting methods such as grouting and the like for reinforcement. When active protection measures cannot be carried out on the pipeline, how to ensure normal use and safe construction of the pipeline is a difficulty in construction in the field.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a construction method for excavating a foundation pit close to a deeply buried large-diameter pipeline, which has higher construction safety coefficient.
In order to solve the technical problems, the invention adopts the following technical scheme:
a construction method for excavating a foundation pit close to a deeply-buried large-diameter pipeline comprises the following steps:
s1, marking the foundation pit outside the influence area of the pipeline as a first foundation pit according to the position and the influence area of the pipeline, excavating earthwork of the first foundation pit, and constructing a bottom plate after the excavation is finished;
s2, marking a foundation pit in the pipeline influence area and right above the pipeline as a third foundation pit, marking a foundation pit between the first foundation pit and the third foundation pit as a second foundation pit, dividing the third foundation pit and the second foundation pit in the pipeline influence area into n layers according to the layer height, and excavating the 1 st layer earthwork of the third foundation pit and the second foundation pit from top to bottom until the excavation of the n-2 th layer earthwork is completed;
s3, dividing the nth-1 layer of earthwork of the second foundation pit into m small sections along the length direction of the pipeline, excavating from the outermost small section of the nth-1 layer of earthwork of the second foundation pit to the middle small section, cleaning and removing the nth layer of earthwork of the second foundation pit after each small section of the nth-1 layer of earthwork of the second foundation pit is excavated, and constructing a bottom plate;
s4, dividing the nth-1 layer of earthwork of the third foundation pit into a small sections a along the length direction of the pipeline, excavating from the outermost small section of the nth-1 layer of the third foundation pit to the middle small section, after each small section of the nth-1 layer of earthwork of the third foundation pit is excavated, cleaning and removing the nth layer of earthwork of the second foundation pit, and constructing the bottom plate until all bottom plate constructions are completed.
As a further improvement to the above technical solution:
in the step S4, after the outermost small section of the (n-1) th floor of the third foundation pit is excavated toward the middle small section, the enclosure structure is constructed on the outer side of the outermost small section, and then the bottom plate is constructed.
In the step S4, the envelope is constructed by using a reverse method.
In the steps S2 and S3, the nth layer of the second foundation pit and the nth layer of the third foundation pit are manually cleaned.
The thickness of the nth layer of the second foundation pit and the thickness of the nth layer of the third foundation pit are respectively 0.2-0.3 m.
The thickness of the (n-1) th layer of the third foundation pit and the thickness of the (n-1) th layer of the third foundation pit are respectively 2-3 m.
The thicknesses of the 1 st layer to the n-2 th layer of the third foundation pit and the second foundation pit are respectively 3 m-4 m.
The width of each small section of the n-1 th layer of earthwork of the third foundation pit divided along the length direction of the pipeline is 9-11 m.
The width of each small section of the n-1 th layer of earthwork of the second foundation pit divided along the length direction of the pipeline is 9-11 m.
In the step S2, excavating the layer 1 earthwork of the third foundation pit and the second foundation pit from top to bottom until the excavation of the layer n-2 earthwork is completed specifically includes: and excavating the layer 1 earthwork of the second foundation pit from top to bottom until the excavation of the layer n-2 earthwork is finished, and excavating the layer 1 earthwork of the third foundation pit from top to bottom until the excavation of the layer n-2 earthwork is finished.
Compared with the prior art, the invention has the advantages that:
the invention can prevent the risk of cracking and damaging the adjacent pipelines within different horizontal height ranges at the bottom of the foundation pit when active protection measures cannot be applied to the pipelines crossing the foundation pit, ensures the safety of foundation pit excavation and foundation structure construction, and can deal with construction environments with higher safety risks.
Drawings
FIG. 1 is a flow chart of the present invention.
Fig. 2 is a schematic diagram of excavation of the third foundation pit.
Fig. 3 is a schematic view of excavation of the third foundation pit and the second foundation pit.
Fig. 4 is a schematic diagram of two-layer excavation on the second foundation pit and the first foundation pit.
Fig. 5 is a schematic diagram of excavation of the third layer of the second foundation pit and the third layer of the first foundation pit.
Fig. 6 is a schematic excavation plane diagram of the third layer of the second foundation pit and the third layer of the first foundation pit.
Fig. 7 is a schematic diagram of third layer excavation of the first foundation pit.
Fig. 8 is a schematic view of a third excavation plane of the first foundation pit.
Fig. 9 is a cross-sectional view taken along line a-a of fig. 8.
The reference numerals in the figures denote: 1. a pipeline; 2. a backhoe excavator; 3. a first foundation pit; 4. a second foundation pit; 41. a first layer of the second foundation pit; 42. a second layer of the second foundation pit; 43. a third layer of the second foundation pit; 431. a third-layer outer small section of the second foundation pit; 432. a third layer middle section at the bottom of the second base pit; 44. a fourth layer of the second foundation pit; 5. a third foundation pit; 51. a first layer of a third foundation pit; 52. a second layer of the third foundation pit; 53. a third layer of the third foundation pit; 531. a third layer of outer small section of the third foundation pit; 532. a third layer middle section of the third foundation pit; 54. a fourth layer of the third foundation pit; 6. a base plate; 7. an enclosure structure; 8. and (3) a steel plate.
Detailed Description
The invention will be described in further detail below with reference to the drawings and specific examples. Unless otherwise specified, the instruments or materials employed in the present invention are commercially available.
As shown in fig. 1 to 9, the construction method for excavating the foundation pit near the deeply buried large-diameter pipeline of the present invention comprises the following construction processes: excavating a first foundation pit 3 outside an affected area of the pipeline 1 → excavating a first layer 41 and a second layer 42 of a second foundation pit 4 in the affected area of the pipeline 1, excavating a first layer 51 and a second layer 52 of a third foundation pit 5 → excavating a third layer 43 of the second foundation pit of the pipeline 1 in a segmented mode, manually cleaning a fourth layer 44 of the second foundation pit and constructing a bottom plate 6 in a segmented mode, excavating a third layer 53 outermost small section of the third foundation pit of the pipeline 1 → constructing a missing building enclosure 7 by adopting a reverse construction method and constructing an outermost small section bottom plate 6 → continuously excavating a third layer 53 middle small section of the third foundation pit of the middle section right above the pipeline 1 → manually cleaning a fourth layer 54 of the third foundation pit and constructing the bottom plate 6 until the bottom plate 6 is completely sealed, and the method comprises the following steps:
s1: determining the position and the influence range of the pipeline 1, excavating earthwork of a first foundation pit 3 outside the influence range, and constructing a bottom plate 6; in this embodiment, the width of the affected area of the duct 1 is determined to be 30.4 m.
S2: dividing the upper earthwork in the affected area of the pipeline 1 into two sections symmetrically along the length direction of the pipeline 1, respectively recording the two sections as a second foundation pit 4 and a third foundation pit 5, wherein the third foundation pit 5 is positioned right above the pipeline 1, the second foundation pit 4 is positioned between the first foundation pit 3 and the third foundation pit 5, determining the layering thickness and the layering of the upper earthwork on the pipeline 1 according to the layering height, and excavating the earthwork in layers until the third layer 43 of the second foundation pit and the third layer 53 of the third foundation pit are completed.
In this embodiment, the length of the third foundation pit 5 right above the pipeline 1 is 14m, and the length of the second foundation pits 4 on both sides of the pipeline 1 is 8 m.
In this embodiment, the height of the whole foundation pit excavation is 8.96m, the second foundation pit 4 and the third foundation pit 5 within the influence range of the pipeline 1 are respectively divided into 4 layers altogether, the second foundation pit 4 is divided into a second foundation pit first layer 41, a second foundation pit second layer 42, a second foundation pit third layer 43 and a second foundation pit fourth layer 44 from top to bottom, the third foundation pit 5 is divided into a third foundation pit first layer 51, a third foundation pit second layer 52, a third foundation pit third layer 53 and a third foundation pit fourth layer 54 from top to bottom, the thicknesses of the second foundation pit first layer 41 and the third foundation pit first layer 51 are both 3.33m, the thicknesses of the second foundation pit second layer 42 and the third foundation pit second layer 52 are both 3.33m, the thicknesses of the second foundation pit third layer 43 and the third foundation pit third layer 53 are both 2m, and the thicknesses of the second foundation pit fourth layer 44 and the third foundation pit fourth layer 54 are both 0.3 m.
In other embodiments, the thicknesses of the second foundation pit fourth layer 44 and the third foundation pit fourth layer 54 are both 0.2m to 0.3m, the thicknesses of the second foundation pit third layer 43 and the third foundation pit third layer 53 are both 2m to 3m, and the thicknesses of the third foundation pit first layer 51, the third foundation pit second layer 52, the second foundation pit first layer 41 and the second foundation pit second layer 42 are 3m to 4m, which may also achieve the same or similar technical effects. The third layer 43 of the second foundation pit and the third layer 53 of the third foundation pit are used as the penultimate layer of the excavation, the value range is proper, if the thickness of the earthwork of the layer is kept large, the excavation time is long, the exposure time of a risk source is long, and the construction risk is increased. Except for the two layers of earthwork, the upper earthwork can be uniformly layered.
S3: and the third layer 43 of the second foundation pit and the third layer 53 of the third foundation pit are respectively divided into three sections along the length direction of the pipeline 1, and the width of each section is determined to be 10.133 m. Excavating from the third-layer outer small section 431 of the second foundation pit to the middle second-foundation-pit third-layer middle small section 432, manually cleaning the earthwork of the fourth layer 44 of the second foundation pit below each small section when excavating the small section, and constructing a small section of the bottom plate 6.
S4: and excavating a third-layer outer small section 531 of the third foundation pit above the pipeline 1, finishing the construction of the building enclosure 7 affected and lost by the pipeline 1 by adopting a reverse construction method, manually cleaning the earthwork of a fourth layer 54 of the third foundation pit below the small section, and finishing the construction of the section of the bottom plate 6.
S5: and (3) continuing to construct a small section 532 in the middle of the third layer of the third foundation pit, manually cleaning the fourth layer 54 of the third foundation pit below the small section, and constructing a small section of bottom plate 6 every time when excavating a small section until all the bottom plates 6 are closed.
In the embodiment, the pipeline 1 is a DN2000 gravity sewage pipe, the pipe body is a round reinforced concrete pipe, and the pipe jacking method is adopted for construction.
In this embodiment, the distance between the pipeline 1 and the bottom of the foundation pit is 0.5 m.
In this embodiment, a backhoe excavator 2 is used for excavation.
In this embodiment, when the backhoe 2 travels on the floor 6 that has been constructed, the steel plate 8 is laid in the travel area, and the surface of the floor 6 is prevented from being damaged by the backhoe 2.
In this example, the thickness of the steel plate 8 was 2 cm.
In this embodiment, the widths of the small sections of the second foundation pit third layer 43 and the third foundation pit third layer 53 in the length direction of the pipeline 1 are 10.133m, and in other embodiments, the widths of the small sections of the second foundation pit third layer 43 and the third foundation pit third layer 53 in the earthwork direction of the pipeline 1 are 9m to 11m, respectively, which can achieve the same or similar technical effects. The invention has proper section width, if too many sections are formed, the width of each section is too small, but the working surface of the excavating machinery is insufficient, the excavating efficiency is influenced, and the construction burden is increased. The long segmentation results in increased construction time, increased exposure time of dangerous sources and increased construction risk. Therefore, according to the parameters of the excavating machine in the embodiment, the excavating machine is determined to be divided into three sections, and the length of each section is about 10m, which is more appropriate.
Although the present invention has been described with reference to the preferred embodiments, it is not intended to be limited thereto. Those skilled in the art can make numerous possible variations and modifications to the present invention, or modify equivalent embodiments to equivalent variations, without departing from the scope of the invention, using the teachings disclosed above. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical spirit of the present invention should fall within the protection scope of the technical scheme of the present invention, unless the technical spirit of the present invention departs from the content of the technical scheme of the present invention.
Claims (5)
1. A construction method for excavating a foundation pit close to a deeply-buried large-diameter pipeline is characterized by comprising the following steps of: the method comprises the following steps:
s1, marking the foundation pit outside the influence area of the pipeline (1) as a first foundation pit (3) according to the position and the influence area of the pipeline (1), excavating earthwork of the first foundation pit (3), and constructing a bottom plate (6) after the excavation is finished;
s2, marking a foundation pit in the influence area of the pipeline (1) and right above the pipeline (1) as a third foundation pit (5), marking a foundation pit between the first foundation pit (3) and the third foundation pit (5) as a second foundation pit (4), dividing the third foundation pit (5) and the second foundation pit (4) in the influence area of the pipeline (1) into n layers according to the layer height, and excavating the earthwork of the layer 1 of the third foundation pit (5) and the second foundation pit (4) from top to bottom until the excavation of the layer n-2 is finished;
s3, dividing the nth-1 layer of earthwork of the second foundation pit (4) into m small sections along the length direction of the pipeline (1), excavating from the outermost small section of the nth-1 layer of earthwork of the second foundation pit (4) to the middle small section, after each small section of the nth-1 layer of earthwork of the second foundation pit (4) is excavated, firstly cleaning and removing the nth layer of earthwork of the second foundation pit (4), and then constructing a bottom plate (6);
s4, dividing the nth-1 layer of earthwork of the third foundation pit (5) into a small sections a along the length direction of the pipeline (1), excavating from the outermost small section of the nth-1 layer of the third foundation pit (5) to the middle small section, after each small section of the nth-1 layer of earthwork of the third foundation pit (5) is excavated, firstly cleaning and removing the nth layer of earthwork of the third foundation pit (5), and then constructing the bottom plate (6) until all the bottom plates (6) are constructed;
the thickness of the nth layer of the second foundation pit (4) and the thickness of the nth layer of the third foundation pit (5) are respectively 0.2-0.3 m;
the thickness of the (n-1) th layer of the third foundation pit (5) and the thickness of the (n-1) th layer of the third foundation pit (5) are respectively 2 m-3 m;
the thicknesses of the 1 st layer to the n-2 th layer of the third foundation pit (5) and the second foundation pit (4) are respectively 3 m-4 m;
the width of each small section of the n-1 th layer of earthwork of the third foundation pit (5) divided along the length direction of the pipeline (1) is 9-11 m.
2. The construction method according to claim 1, characterized in that: in the step S4, after the outermost small section of the (n-1) th layer of the third foundation pit (5) is excavated to the middle small section, the enclosure structure (7) is constructed on the outer side of the outermost small section, and then the bottom plate (6) is constructed.
3. The construction method according to claim 2, characterized in that: in the step S4, the building envelope (7) is constructed by using a reverse construction method.
4. The construction method according to any one of claims 1 to 3, characterized in that: in the steps S3 and S4, the nth layer of the second foundation pit (4) and the nth layer of the third foundation pit (5) are manually cleaned.
5. The construction method according to any one of claims 1 to 3, characterized in that: in the step S2, excavating the layer 1 earthwork of the third foundation pit (5) and the second foundation pit (4) from top to bottom until the excavation of the layer n-2 earthwork is completed specifically includes: excavating the layer 1 earthwork of the second foundation pit (4) from top to bottom until the excavation of the layer n-2 earthwork is finished, and excavating the layer 1 earthwork of the third foundation pit (5) from top to bottom until the excavation of the layer n-2 earthwork is finished.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010001188.7A CN111042145B (en) | 2020-01-02 | 2020-01-02 | Construction method for excavating foundation pit near deep-buried large-diameter pipeline |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010001188.7A CN111042145B (en) | 2020-01-02 | 2020-01-02 | Construction method for excavating foundation pit near deep-buried large-diameter pipeline |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111042145A CN111042145A (en) | 2020-04-21 |
| CN111042145B true CN111042145B (en) | 2022-03-11 |
Family
ID=70243742
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010001188.7A Active CN111042145B (en) | 2020-01-02 | 2020-01-02 | Construction method for excavating foundation pit near deep-buried large-diameter pipeline |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111042145B (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003064712A (en) * | 2001-08-27 | 2003-03-05 | Fusao Sakano | Construction method for chipping existing underground structure |
| CN103510520A (en) * | 2013-10-09 | 2014-01-15 | 上海市建工设计研究院有限公司 | Sectionalized construction method of deep and large foundation pit |
| CN104452773A (en) * | 2014-11-18 | 2015-03-25 | 上海建工七建集团有限公司 | Construction method for foundation pit support with strengthening structure |
| CN104612162A (en) * | 2014-12-15 | 2015-05-13 | 中铁二十局集团第三工程有限公司 | Subway station deep foundation pit excavation construction method |
| CN105421463A (en) * | 2015-11-04 | 2016-03-23 | 中建三局集团有限公司 | Longitudinal excavation construction method of long-span dense-support super-long deep foundation pit |
| CN107313430A (en) * | 2016-04-27 | 2017-11-03 | 上海十三冶建设有限公司 | The deep big foundation pit subregion construction method of three face Nearby Structures |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107940102B (en) * | 2017-11-21 | 2023-05-26 | 上海建工四建集团有限公司 | Underground raw water pipeline protection construction method |
-
2020
- 2020-01-02 CN CN202010001188.7A patent/CN111042145B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003064712A (en) * | 2001-08-27 | 2003-03-05 | Fusao Sakano | Construction method for chipping existing underground structure |
| CN103510520A (en) * | 2013-10-09 | 2014-01-15 | 上海市建工设计研究院有限公司 | Sectionalized construction method of deep and large foundation pit |
| CN104452773A (en) * | 2014-11-18 | 2015-03-25 | 上海建工七建集团有限公司 | Construction method for foundation pit support with strengthening structure |
| CN104612162A (en) * | 2014-12-15 | 2015-05-13 | 中铁二十局集团第三工程有限公司 | Subway station deep foundation pit excavation construction method |
| CN105421463A (en) * | 2015-11-04 | 2016-03-23 | 中建三局集团有限公司 | Longitudinal excavation construction method of long-span dense-support super-long deep foundation pit |
| CN107313430A (en) * | 2016-04-27 | 2017-11-03 | 上海十三冶建设有限公司 | The deep big foundation pit subregion construction method of three face Nearby Structures |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111042145A (en) | 2020-04-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Tan et al. | Forensic diagnosis of a leaking accident during excavation | |
| Tan et al. | Zoned excavation of an oversized pit close to an existing metro line in stiff clay: Case study | |
| CN108442382B (en) | In-situ protection and enclosure soil-retaining structure for pressure pipeline crossing deep foundation pit and construction method | |
| CN104264683B (en) | Building concave shape ultra-deep foundation pit subregion supporting method is protected for three around literary composition | |
| CN103541364A (en) | Design and construction method of large area foundation pit deformation control with roundabout method | |
| CN112761188A (en) | Construction structure and construction method of concrete inverted hanging well suitable for mucky soil | |
| CN111139837A (en) | Method for simultaneously excavating multiple base pits at crossed subway in soft soil area | |
| CN104099946B (en) | Inspection-pit between a kind of Novel top pipeline section | |
| CN111042145B (en) | Construction method for excavating foundation pit near deep-buried large-diameter pipeline | |
| CN111764373A (en) | Construction method of underground continuous wall under condition of non-removable underground barrier | |
| CN105179808B (en) | Pipe laying construction method after the pre- ditching of long range submerged pipeline | |
| CN209941754U (en) | High-voltage power pipe culvert in-situ protection structure | |
| CN112145792A (en) | PCCP pipeline construction method | |
| CN104532849B (en) | A kind of foundation ditch on top of underground railway tunnel excavation method | |
| CN214090006U (en) | Basement lateral wall post-cast strip block structure | |
| CN210636422U (en) | Underground continuous wall joint structure | |
| CN112726667A (en) | Semi-rigid assembly type comprehensive pipe gallery and construction method thereof | |
| CN113006085A (en) | Supporting-first-excavating foundation pit supporting system for inclined prefabricated steel piles and construction method of supporting-second-excavating foundation pit supporting system | |
| CN219673490U (en) | Push pipe for drainage pipeline construction | |
| CN220102278U (en) | Connecting pipe construction structure for connecting pipe point of raw water engineering in narrow space | |
| CN114962781B (en) | Construction method for penetrating pipeline below existing pipeline | |
| CN103526763A (en) | Cast-in-place pile, root pile and jet grouting pile composite-type foundation pit supporting method | |
| Yoo et al. | Excavation-induced buried pipeline failure–A case study | |
| CN113373901B (en) | Overlapping shield tunnel house foundation reinforcing structure next to house and construction method | |
| CN216892565U (en) | Non-excavation of sewer line inspection shaft bottom part local seepage restores structure |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |