CN102359112A - Method for bracing foundation pit by using steel box piles - Google Patents

Method for bracing foundation pit by using steel box piles Download PDF

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Publication number
CN102359112A
CN102359112A CN2011102073821A CN201110207382A CN102359112A CN 102359112 A CN102359112 A CN 102359112A CN 2011102073821 A CN2011102073821 A CN 2011102073821A CN 201110207382 A CN201110207382 A CN 201110207382A CN 102359112 A CN102359112 A CN 102359112A
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China
Prior art keywords
stake
steel case
steel
foundation pit
pile
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CN2011102073821A
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Chinese (zh)
Inventor
周心培
周磊
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China Railway Siyuan Survey and Design Group Co Ltd
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China Railway Siyuan Survey and Design Group Co Ltd
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Priority to CN2011102073821A priority Critical patent/CN102359112A/en
Publication of CN102359112A publication Critical patent/CN102359112A/en
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Abstract

The invention discloses a method for bracing a foundation pit by using steel box piles. The method comprises the following steps of: (1) making the steel box piles: welding profile steels or steel plates into a steel box pile box, and arranging transverse connecting members among the piles at two sides of the steel box pile box; (2) arranging a ground guiding structure: pouring reinforced concrete to form a foundation pit bracing guiding wall or arranging steel members to form the ground guiding structure; (3) positioning: sequentially positioning a plurality of steel box piles along the guiding structure respectively; (4) sinking the piles: driving the steel box piles into soil; (5) lengthening the piles: when the foundation pit is relatively deep and the prefabricated steel box piles are not long enough, lengthening the steel box piles through pile body lengthening members; and (6) digging and supporting: digging layer by layer, arranging enclosing purlins and erecting supports in the foundation pit of the steel box piles, and completing the construction. The method has the advantages of high construction efficiency, short construction period, reliable pile forming quality, low engineering cost, resource economization and the like, and is particularly suitable for weak strata in which holes and grooves are not easily formed such as silt soil, peat soil, saturated water-containing sand layers, powdery clay, soil sand and the like.

Description

Utilize the stake of steel case to carry out the method for bracing of foundation pit
Technical field
The present invention relates to underground construction bracing of foundation pit technical field in the building field, is a kind of foundation pit enclosure method that mucky soil, cumulosol, saturated aqueous layer of sand, silty clay and native sand alternating layers etc. are difficult for the soft stratum of pore-forming, grooving that is specially adapted to.
Background technology
Many open cut deep foundation ditchs are arranged in underground railway, urban road and the high building project.The space enclosing structure of existing foundation ditch adopts multiple retaining forms such as diaphragm wall, bored pile, driven pile, stiffness cement churning (SMW) stake usually.
The soft stratum that is difficult for pore-forming, grooving for mucky soil, cumulosol, saturated aqueous layer of sand, silty clay and native sand alternating layers etc.; For example: the soft soil layer that Yangtze River Delta, the Delta of the Pearl River and Bohai Rim etc. are coastal and along the alluvial terrace of rivers such as the Changjiang river and the Zhujiang River; Adopt existing bracing of foundation pit technology; Obviously have defective: the drawback of diaphragm wall, drilled pile etc. is higher, the long construction period of cost, and is bigger to the influence of environment; The shaped steel of stiffness cement churning (SMW) stake reclaims and has certain difficulty, and construction quality is difficult for guaranteeing, unavoidably to the pollution of environment, and is not suitable for darker foundation ditch; Steel sheet pile only is applicable to the shallow foundation hole.So, the new foundation pit enclosure structure of essential exploitation.
Summary of the invention
The purpose of this invention is to provide the foundation pit enclosure method that is applicable to soft stratum.
For realizing above-mentioned purpose, the present invention has designed a kind of method of utilizing the stake of steel case to carry out bracing of foundation pit, may further comprise the steps:
1. make the stake of steel case: adopt shaped steel or steel plate to be welded into steel case stake casing, the both sides of steel case stake casing are provided with horizontal connecting elements between stake;
2. install the ground guide frame: build steel concrete as the guiding wall of bracing of foundation pit or install steel component as the ground guide frame;
3. locate: the stake of many steel casees is located along guide frame respectively successively;
4. pile sinking: the stake of steel case suppressed bury;
5. pile extension: when the dark prefabricated steel case stake of foundation ditch falls short of, through the stake of pile body spreading member spreading steel case;
6. stage excavation encloses purlin, sets up support in the foundation ditch side installation of steel case stake, and accomplishes construction.
In technique scheme: the steel case stake casing cross section of step described in 1. is rectangular, square, circular, convex shape, sector or polygon.
Step 3. in crane gear with the stake of steel case sling, centering is in place, it is firm that first steel case stake adopts special stand to help, and makes that pile body is vertical, accurate positioning, and make the horizontal connecting elements cover of adjacent steel case stake be inserted into the position.
Step 3. in, the stake between connector be drag hook shape collapsible type connecting elements.
Step 4. in the bigger part of penetrating resistance adopt the method pile sinking of stake core casting.
4. install pile cover in the upper end of steel case stake in step in, adopt hydraulic pressure high-frequency vibratory hammer or other pile drivers that the stake of steel case is squeezed in the soil, or adopt pile press to be pressed in the soil.
Before 2. step carries out after 1. step is accomplished, carry out the relocation site underground pipelines earlier, the stone in the desurfacing miscellaneous fill, underground residual structure etc. hinder the object of pile sinking.
Comprise the steel gusset plate that is installed in sidewall around the steel case stake casing end at the pile body spreading member of step described in 5.; Steel case stake end and steel gusset plate are provided with some bolts hole, adopt high-strength bolt that steel case stake casing adjacent on the vertical direction is linked together.
Step 5. in pile body spreading member be arranged in that to enclose purlin upper and lower, on the web of casing side, be provided with the operation hand hole.
The present invention utilizes the stake of steel case to carry out the method for bracing of foundation pit, has the following advantages:
1, at the construction field (site), directly the stake of steel case is beaten or is pressed into and be combined into underground piling wall in the soil, for foundation ditch provides safe and reliable going along with sb. to guard him, efficiency of construction is high, short construction period;
2, strict with the designing requirement manufacturing in the steel case stake of professional factory weldering system, reliable in quality helps pile quality;
3, do not have preceding grooving or the pore forming process of traditional fender post cast pile, can avoid the pollution of mud, do not have the concrete pouring flow chart yet, help protecting environment environment;
4, adopt hook-shaped collapsible type joint to connect between the stake of steel case, connect tightly between the stake of steel case, be difficult for taking place seepage.Can increase cement churning or ejection for water plugging in case of necessity, the spray scope is controlled easily, and waterproof effect is reliable;
5, the stake of steel case is recyclable utilizes again, can greatly reduce construction costs, economizes on resources;
The method that the present invention utilizes the stake of steel case to carry out bracing of foundation pit is specially adapted to the soft stratum that mucky soil, cumulosol, saturated aqueous layer of sand, silty clay and native sand alternating layers etc. are difficult for pore-forming, grooving, for example coastal soft soil layer such as Yangtze River Delta, the Delta of the Pearl River and Bohai Rim and along the alluvial terrace soft stratum of rivers such as the Changjiang river and the Zhujiang River.
Description of drawings
Fig. 1 is a steel case pile foundation pit enclosure structural representation of the present invention;
Fig. 2 is the sectional elevation of Fig. 1;
Fig. 3 is first kind of cross-sectional structure sketch map of steel case stake casing that the present invention is provided with two through holes;
Fig. 4 is the syndeton of steel case stake shown in two a Fig. 3 sketch map;
Fig. 5 is second kind of cross-sectional structure sketch map of steel case stake casing that the present invention is provided with two through holes;
Fig. 6 is the syndeton of steel case stake shown in two a Fig. 5 sketch map;
Fig. 7 is the third cross-sectional structure sketch map of steel case stake casing that the present invention is provided with two through holes;
Fig. 8 is the syndeton of steel case stake shown in two a Fig. 7 sketch map;
Fig. 9 is the 4th kind of cross-sectional structure sketch map of steel case stake casing that the present invention is provided with two through holes;
Figure 10 is the syndeton of steel case stake shown in two a Fig. 9 sketch map;
Figure 11 is the 5th kind of cross-sectional structure sketch map of steel case stake casing that the present invention is provided with two through holes;
Figure 12 is the syndeton of steel case stake shown in two a Figure 11 sketch map;
Figure 13 is the 6th kind of cross-sectional structure sketch map of steel case stake casing that the present invention is provided with two through holes;
Figure 14 is the syndeton of steel case stake shown in two a Figure 13 sketch map;
Figure 15 is the 7th kind of cross-sectional structure sketch map of steel case stake casing that the present invention is provided with two through holes;
Figure 16 is the 8th kind of cross-sectional structure sketch map of steel case stake casing that the present invention is provided with two through holes;
Figure 17 is the pile body spreading member cross-sectional structure sketch map of steel case of the present invention stake;
Figure 18 is the left TV structure sketch map of Figure 17;
Figure 19 is first kind of mode structural representation of waterproof between piles of the present invention;
Figure 20 is the second way structural representation of waterproof between piles of the present invention;
Figure 21 is the third mode structural representation of waterproof between piles of the present invention;
Figure 22 is the 4th a kind of mode structural representation of waterproof between piles of the present invention;
Among the figure: 1-ground, the 2-base, 3-steel case stake casing, 4-encloses purlin, and the 5-steel supports, 6-pile body spreading member, 7-connector, 8-gusset plate, 9-high-strength bolt, 10-ejection for water plugging district, 11-churning sealing district, 12, hand hole.
The specific embodiment
Below in conjunction with accompanying drawing and specific embodiment the present invention is made further detailed description:
Utilize the stake of steel case to carry out the method for bracing of foundation pit, may further comprise the steps:
At first; Make the stake of steel case: adopt shaped steel or steel plate to be welded into the steel case stake of prefabricated size; Like Fig. 1, Fig. 2 and shown in Figure 3; That processes comprises steel case stake casing 3, is provided with to the bilateral symmetry of steel case stake casing 3 to be used for the connecting elements 7 that is connected between the laterally adjacent steel case stake, is provided with the long drag hook shape collapsible type connecting elements of system in the weldering of the side of steel case stake casing 3; Make between the adjacent steel case stake company of drawing each other, and make the connecting elements interface of previous steel case stake become the pile sinking gathering sill of next steel case stake.Drag hook shape collapsible type connecting elements belongs to " hinged " between stake, therefore is easy to make steel case piling wall to make the broken line shape of little drift angle.
Second step, hoisted in position: the steel case stake of making is transported to the job location, installs ground 1 guide frame, build steel concrete as the guiding wall of bracing of foundation pit or install steelwork as guide frame; Should move the pipeline under the ground 2 before guide frame is installed, the stone in the desurfacing miscellaneous fill, underground residual structure etc. hinder the object of pile sinking;
Hang upright steel case stake then and connect the stake of adjacent steel case: with crane with the stake of steel case sling, centering is in place, it is firm that first steel case stake adopts special stand to help, and makes that pile body is vertical, accurate positioning, and make the horizontal connecting elements cover of adjacent steel case stake be inserted into the position.
In the 3rd step, carry out pile sinking: pile cover is installed in the upper end in the stake of steel case, adopts hydraulic pressure high-frequency vibratory hammer or pile driver that the stake of steel case is squeezed in the soil, or adopts pile press to be pressed in the soil; Meet penetrating resistance too big, bury at need, a core casting can suitably be adopted in the part;
And then carry out pile extension: when the dark prefabricated steel case stake of foundation ditch falls short of, can pass through the stake of pile body spreading member spreading steel case; The pile body spreading member of steel case stake should be consulted shown in Figure 1 enclosing the upper and lower staggered left and right separation of purlin.For ease of installing bolt, the predeterminable operation hand hole 12 in the appropriate location of pile body side web.
Excavation supports at last: in the excavation support process or after accomplishing; If find to have between stake the situation of percolating water; Then need carry out waterproof between piles and handle, at the upstream face one side making cement churning sealing of the connecting elements between the adjacent steel case stake or reserving and doing ejection for water plugging in the cavity and handle, and accomplish construction.
The cross section of steel case stake casing 3 can be multiple shape; And can be according to foundation depth, foundation ditch shape and ground 2 strata condition; The cross-sectional profile of steel case stake casing 3 can adopt circle, square, oval, isosceles triangle or polygon; The empty form that adopts single chamber or multi-cavity in the cross section of steel case stake casing 3 is like Fig. 3-shown in Figure 16.According to the soil pressure size, select suitable cross-sectional shape and interior empty branch hole for use.The soft person of squeezing into of being prone in stratum can use the single pile cross section of broad, and ground 1 should be adopted narrower single pile cross section more firmly.The piling wall turning point can be selected the steel case stake of convex shape cross sectional shape for use; Laterally the connector between the adjacent steel case stake casing 3 adopts drag hook shape collapsible type connector 7, like Fig. 3-shown in Figure 16, can establish a connector 7 between two, also can establish two connectors 7; But connector 7 centered, but also single-sided arrangement; Like Figure 17 and shown in Figure 180, around steel case stake casing 3 ends steel gusset plate 8 is installed, high-strength bolt 9 is installed on the steel node 8, adopt the high-strength bolt that adds the steel gusset plate that vertical adjacent steel case stake casing 3 is connected.
After whole engineering is accomplished, extract the stake of steel case one by one, after the recovery, can supply to reuse through the maintenance finishing with crane gear and piling facility.

Claims (9)

1. method of utilizing the stake of steel case to carry out bracing of foundation pit is characterized in that may further comprise the steps:
1. make the stake of steel case: adopt shaped steel or steel plate to be welded into steel case stake casing, the both sides of steel case stake casing are provided with horizontal connecting elements between stake;
2. install the ground guide frame: build steel concrete as the guiding wall of bracing of foundation pit or install steel component as the ground guide frame;
3. locate: the stake of many steel casees is located along guide frame respectively successively;
4. pile sinking: squeeze into or be pressed into the stake of steel case in the soil;
5. pile extension: when the dark prefabricated steel case stake of foundation ditch falls short of, through the stake of pile body spreading member spreading steel case;
6. stage excavation encloses purlin, sets up support in the foundation ditch side installation of steel case stake, and accomplishes construction.
2. the method for utilizing the stake of steel case to carry out bracing of foundation pit according to claim 1 is characterized in that: the steel case stake casing cross section of step described in 1. is rectangular, square, circular, convex shape, sector or polygon.
3. the method for utilizing the stake of steel case to carry out bracing of foundation pit according to claim 1; It is characterized in that: step 3. in crane gear with the stake of steel case sling, centering is in place; First steel case stake adopts special stand to help firmly; Make vertical, the accurate positioning of pile body, and make the horizontal connecting elements cover of adjacent steel case stake be inserted into the position.
4. the method for utilizing the stake of steel case to carry out bracing of foundation pit according to claim 3 is characterized in that: step 3. in, the stake between connector be drag hook shape collapsible type connecting elements.
5. the method for utilizing the stake of steel case to carry out bracing of foundation pit according to claim 3 is characterized in that: step 4. in the bigger part of penetrating resistance adopt the method pile sinking of stake core casting.
6. the method for utilizing the stake of steel case to carry out bracing of foundation pit according to claim 1; It is characterized in that: step is installed pile cover in the upper end of steel case stake in 4.; Adopt hydraulic pressure high-frequency vibratory hammer or other pile drivers that the stake of steel case is squeezed in the soil, or adopt pile press to be pressed in the soil.
7. the method for utilizing the stake of steel case to carry out bracing of foundation pit according to claim 1; It is characterized in that: before 2. step carries out after 1. step is accomplished; Carry out the relocation site underground pipelines earlier, the stone in the desurfacing miscellaneous fill, underground residual structure etc. hinder the object of pile sinking.
8. the method for utilizing the stake of steel case to carry out bracing of foundation pit according to claim 1; It is characterized in that: the pile body spreading member of step described in 5. comprises the steel gusset plate that is installed in sidewall around the steel case stake casing end; Steel case stake end and steel gusset plate are provided with some bolts hole, adopt high-strength bolt that steel case stake casing adjacent on the vertical direction is linked together.
9. according to claim 1 or the 8 described methods of utilizing the stake of steel case to carry out bracing of foundation pit, it is characterized in that: step 5. in pile body spreading member be arranged in that to enclose purlin upper and lower, on the web of casing side, be provided with the operation hand hole.
CN2011102073821A 2011-07-22 2011-07-22 Method for bracing foundation pit by using steel box piles Pending CN102359112A (en)

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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102626946A (en) * 2012-03-07 2012-08-08 嘉兴中正桩业有限公司 Manufacture method for concrete irregular fender post
CN102677958A (en) * 2012-04-20 2012-09-19 浙江水利水电专科学校 Building site greening ecological enclosing wall and construction method
CN103643673A (en) * 2013-11-04 2014-03-19 张延策 Self-advancing recyclable steel pipe pile and construction method
CN103696430A (en) * 2014-01-03 2014-04-02 张延策 Construction process of non-grouted recyclable steel-pipe piles
CN103711124A (en) * 2013-12-30 2014-04-09 江苏省交通科学研究院股份有限公司 Concrete tapered pile foundation
CN104131570A (en) * 2014-06-26 2014-11-05 中冶天工上海十三冶建设有限公司 Steel box enclosure device for foundation pit construction and construction method thereof
CN111827266A (en) * 2020-07-21 2020-10-27 重鑫岩土技术(上海)有限公司 Method for constructing underground continuous wall by using steel caisson technology
CN114808924A (en) * 2022-05-27 2022-07-29 中建交通建设集团有限公司 Construction method of assembled steel-concrete underground continuous wall

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CN102011398A (en) * 2010-10-23 2011-04-13 孔超 Device and method for forming high-frequency vibratory pressing displacement bored concrete pile
CN102094425A (en) * 2010-12-24 2011-06-15 中铁六局集团有限公司 Foundation pit construction method adopting shallow buried depth Larsen steel plate pile as protective cofferdam
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Publication number Priority date Publication date Assignee Title
US5595459A (en) * 1995-10-02 1997-01-21 Lomonaco; Stenis Cofferdam for 4', 8' and 12' diameter tanks
CN201137076Y (en) * 2007-12-17 2008-10-22 杨峰 Deep pit reinforced concrete guard post
CN101255696A (en) * 2008-04-14 2008-09-03 河南国基建设集团有限公司 PHC pipe-pile pile-anchor combined support water stop construction method
CN201635071U (en) * 2010-02-02 2010-11-17 中交二公局第五工程有限公司 Profile steel lock-type steel pipe pile enclosing structure
CN102011398A (en) * 2010-10-23 2011-04-13 孔超 Device and method for forming high-frequency vibratory pressing displacement bored concrete pile
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CN102094425A (en) * 2010-12-24 2011-06-15 中铁六局集团有限公司 Foundation pit construction method adopting shallow buried depth Larsen steel plate pile as protective cofferdam

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102626946A (en) * 2012-03-07 2012-08-08 嘉兴中正桩业有限公司 Manufacture method for concrete irregular fender post
CN102677958A (en) * 2012-04-20 2012-09-19 浙江水利水电专科学校 Building site greening ecological enclosing wall and construction method
CN103643673A (en) * 2013-11-04 2014-03-19 张延策 Self-advancing recyclable steel pipe pile and construction method
CN103711124A (en) * 2013-12-30 2014-04-09 江苏省交通科学研究院股份有限公司 Concrete tapered pile foundation
CN103711124B (en) * 2013-12-30 2016-03-23 苏交科集团股份有限公司 Concrete tapered pile basis
CN103696430A (en) * 2014-01-03 2014-04-02 张延策 Construction process of non-grouted recyclable steel-pipe piles
CN103696430B (en) * 2014-01-03 2018-07-06 张延策 The construction technology of the recyclable steel-pipe pile of not slip casting
CN104131570A (en) * 2014-06-26 2014-11-05 中冶天工上海十三冶建设有限公司 Steel box enclosure device for foundation pit construction and construction method thereof
CN111827266A (en) * 2020-07-21 2020-10-27 重鑫岩土技术(上海)有限公司 Method for constructing underground continuous wall by using steel caisson technology
CN114808924A (en) * 2022-05-27 2022-07-29 中建交通建设集团有限公司 Construction method of assembled steel-concrete underground continuous wall
CN114808924B (en) * 2022-05-27 2023-04-14 中建交通建设集团有限公司 Construction method of assembled steel-concrete underground diaphragm wall

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Application publication date: 20120222