CN110130393A - A kind of underwater foundation pit drilling of soft rock and punching point arrangement method - Google Patents
A kind of underwater foundation pit drilling of soft rock and punching point arrangement method Download PDFInfo
- Publication number
- CN110130393A CN110130393A CN201910427674.2A CN201910427674A CN110130393A CN 110130393 A CN110130393 A CN 110130393A CN 201910427674 A CN201910427674 A CN 201910427674A CN 110130393 A CN110130393 A CN 110130393A
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- Prior art keywords
- drilling
- foundation pit
- punching
- underwater foundation
- diameter
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- 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.)
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Classifications
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D19/00—Keeping dry foundation sites or other areas in the ground
- E02D19/02—Restraining of open water
- E02D19/04—Restraining of open water by coffer-dams, e.g. made of sheet piles
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D27/00—Foundations as substructures
- E02D27/32—Foundations for special purposes
- E02D27/52—Submerged foundations, i.e. submerged in open water
- E02D27/525—Submerged foundations, i.e. submerged in open water using elements penetrating the underwater ground
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B7/00—Special methods or apparatus for drilling
Abstract
The invention discloses a kind of underwater foundation pit drilling of soft rock and punching point arrangement methods, the following steps are included: (1) determines the size and depth of underwater foundation pit, underwater foundation pit elder generation compartment drilling, it forms remaining rock stratum like cellular cylinder, then is cut by percussive drill impact, is broken；(2) torque specification parameter of rotary drilling rig and the diameter of respective bore are determined according to the soft or hard and integrated degree of geology, stable case when according to bore operation determines the hole location clear distance of drilling.(3) diameter of punching is determined according to the size like honeycomb cylinder region formed after drilling, the all standing to guarantee remaining area is laid in the occlusion of punching point, and the diameter of punching point is determined according to impact operation degree of stability and single-point target efficiency.The present invention improves the construction efficiency and construction precision of the underwater excavation of foundation pit of soft rock, has ensured quick smooth sinking, the implantation of steel boxed cofferdam.
Description
Technical field
The invention belongs to bridge deepwater foundation technical field of construction, in particular to a kind of underwater foundation pit of soft rock drills and punching
Point arrangement method.
Background technique
It constructs currently, steel boxed cofferdam technology has been widely used in bridge deepwater foundation, but is rock, base in riverbed
When rock class, riverbed need to be excavated to underwater foundation pit of corresponding size, so that steel boxed cofferdam smoothly sinks and implantation.
Subaqueous rock class excavation of foundation pit mainly has mechanical excavation and underwater demolition two ways.
Mechanical excavation is suitable for pan soil and soft rock, generally boat-carrying high-front shovel operation.It is benefit when mechanical excavation operation
Hull is coupled by ship anchor with flexible cable, hull shakes obvious when operation, can not real fixed hull position, cannot be to excavating
Machine provides enough reversed support forces, therefore it is lower to excavate efficiency, and cutting depth is limited by excavator brachium.
Underwater demolition be suitable for hard rock, but explosion formality declaration, scarfing cinder construction etc. long period, and exist at
This investment is big, security risk is high, influences many insufficient and drawbacks such as big to existing construction installation and natural ecology.
In some projects, such as the Suining township Lao Chi to Pengxi study ditch farming family crosses grand bridge project, bridge site area riverbed
Matter is cobble and weathered mudstone.Cobble overburden cover reaches 3m, and weathered mudstone intensity reaches 5.1MPa, and it is soft that rock mass is divided into IV class
The excavation effect of stone, underwater drilling and blasting is poor.And the maximum construction depth of water reaches 19.5m, the backactors such as high-front shovel at pier position
Tool ability is unable to reach requirement.
For the excavation of the underwater foundation pit of soft rock, the rotary drilling rig drilling of use and the technique of percussive drill punching do not have still at present
Have to form a set of efficient, reliable, unified technology and standard criterion, directly restrict underwater excavation efficiency and applies
The promotion of work precision.
Summary of the invention
For the technical problems in the prior art, the present invention provides a kind of underwater foundation pit drilling of soft rock and punching point
Distribution method is constructed using the group technology of rotary drilling rig drilling and percussive drill punching, solves the underwater excavation of foundation pit of soft rock
Problem, ensured steel boxed cofferdam it is smooth sinking and implantation.
In order to solve the above technical problems, the technical solution adopted by the present invention is that:
A kind of underwater foundation pit drilling of soft rock and punching point arrangement method, comprising the following steps:
(1) size and depth of underwater foundation pit are determined according to steel boxed cofferdam size and bed elevation, underwater foundation pit first leads to
The drilling of rotary drilling rig compartment is crossed, forms remaining rock stratum like cellular cylinder, then is cut by percussive drill impact, is broken
It is broken；
(2) according to the soft or hard and integrated degree of geology determine rotary drilling rig torque specification parameter and respective bore it is straight
Diameter, stable case when further according to bore operation determine the hole location clear distance of drilling.
(3) size like honeycomb cylinder region formed after being drilled according to rotary drilling rig determines the straight of percussive drill punching
Diameter size, the occlusion of punching point are laid all standing to guarantee remaining area, are impacted according to impact operation degree of stability and single-point
Efficiency determines the diameter of punching point.
Preferably, the size range of the underwater foundation pit in step (1) than steel boxed cofferdam surrounding sideline respectively extend out 1m~
1.5m, the surrounding crater wall of underwater foundation pit perpendicular shape from top to bottom.
Preferably, the range of the bore diameter of rotary drilling rig is 1.5m~2.2m in step (2).
Preferably, rotary drilling rig drilling the ratio between the hole location clear distance and bore diameter are 1:3~1:4.
Preferably, the drilling point is evenly arranged mode, the drilling hole location of same row and same row using vertical, horizontal
Diameter and clear distance are all the same.
Preferably, the percussive drill punching hole diameter is greater thanWherein, D1 is bore diameter, L
For the hole location clear distance that drills.
Preferably, the punching point diameter is 1.8m~2.5m.
Preferably, the ratio between the percussive drill punching pitch and punching hole diameter are 2:3~5:6.
Compared with prior art, the present invention has the beneficial effects that
1) construction efficiency and construction precision for improving the underwater excavation of foundation pit of soft rock have ensured the quick suitable of steel boxed cofferdam
Benefit sinking, implantation.
2) rotary drilling rig and respective bore diameter that respective performances parameter is selected according to the soft or hard and integrated degree of geology, are bored
Hole point is vertically and horizontally uniformly distributed, and the hole location clear distance by adjusting rotary drilling rig drilling makes bore operation reach more stable shape
State ensure that bore operation construction precision and construction efficiency.
3) according to the corresponding punching of honeycomb rock stratum size and Load for construction ability selection formed after drilling
Bore dia, and so that the stability for impacting operation and target efficiency is reached more excellent state, and punching by adjusting punching pitch size
Point arrangement ensure that all standing of remaining formation area.
4) by reasonably being designed rotary digging drilling hole diameter and hole location clear distance, percussive drill punching hole diameter and pitch-row and
Arrangement forms a set of efficient, reliable technology and standard criterion, is the construction efficiency and construction of the underwater excavation of foundation pit of soft rock
The promotion of precision provides effectively reference and reliable basis.
Detailed description of the invention
Fig. 1 is a kind of drilling point plane of arrangement of soft rock underwater foundation pit drilling and punching point arrangement method in the present invention
Schematic diagram；
Fig. 2 is a kind of punching point plane of arrangement of soft rock underwater foundation pit drilling and punching point arrangement method in the present invention
Schematic diagram；
Fig. 3 is a kind of drilling and punching point cloth that the underwater foundation pit of soft rock drills with punching point arrangement method in the present invention
Horizontalization face perspective view of the explosion.
In figure, 1. underwater foundation pits；2. drill point；3. the first punching point；4. the second punching point.
Specific embodiment
Technical solution in order to enable those skilled in the art to better understand the present invention, in the following with reference to the drawings and specific embodiments
It elaborates to the present invention.
Embodiment one
As shown in Figure 1 to Figure 3, embodiment of the invention discloses a kind of underwater foundation pit drilling of soft rock and punching point arrangements
Method, comprising the following steps:
(1) size and depth of underwater foundation pit 1 are determined according to steel boxed cofferdam size and bed elevation, underwater foundation pit 1 is first
It is drilled by rotary drilling rig compartment, forms remaining rock stratum like cellular cylinder, then cut by percussive drill impact,
It is broken；
(2) according to the soft or hard and integrated degree of geology determine rotary drilling rig torque specification parameter and respective bore it is straight
Diameter, stable case when further according to bore operation determine the hole location clear distance of drilling.
(3) size like honeycomb cylinder region formed after being drilled according to rotary drilling rig determines the straight of percussive drill punching
The all standing to guarantee remaining area is laid in diameter size, the occlusion of punching point, and the pore size of punching point is according to impact operation
Degree of stability and single-point target efficiency carry out selection determination.
In step (1), the size of underwater foundation pit is determined according to the outside dimension of steel boxed cofferdam, to guarantee steel boxed cofferdam
Smoothly to sink, the size range of underwater foundation pit 1 respectively extends out 1m~1.5m compared with steel boxed cofferdam surrounding sideline, and the four of underwater foundation pit 1
All crater walls are vertical configuration from top to bottom.Underwater foundation pit 1 lays drilling point 2 by compartment, is bored from top to bottom by rotary drilling rig
Take multiple pilot holes；The first punching point 3 and the second punching point are laid by biting connecions in the region like honeycomb type remaining after drilling again
Position 4, potential energy and instantaneous impact when using impact hammer head free-falling impact soil layer and cut, are crushed and break up rock.
In step (2), according to the optimization of rotary drilling rig torsional performance parameter size and drilling construction workload, cost, really
The bore diameter D1 for determining rotary drilling rig is 1.5m~2.2m.When bore diameter is excessive it is then more demanding to the performance parameter of drilling machine and
Drilling efficiency is lower；Then the drilling hole amount needed for the underwater foundation pit of same size increases when bore diameter is too small, increases construction and makees
Industry amount and construction cost.
Drilling point 2 is evenly arranged mode using vertical, horizontal, the 2 diameter D1 of drilling point of same row and same row and net
It is all the same away from L.Rotary drilling rig drills the ratio between hole location clear distance L and bore diameter D1 as 1:3~1:4, avoids because hole location clear distance L is too small
The rough sledding that " run and bore " occurs influences construction speed or because of the excessive influence punched hole construction efficiency of hole location clear distance L and construction speed.
When hole location clear distance L is too small, remaining formation honeycombed rock level product is smaller after drilling, when the area of plane of single-point rock stratum is less than punching
Percussion area when hole, in subsequent punched hole construction, Yi Fasheng " sliding hammer " phenomenon, that is, impact hammer head is unstable, topples over, slides
It falls, influences construction efficiency.In addition, when hole location clear distance L is too small in drilling Yi Fasheng " run bore " rough sledding, i.e. drilling rod to having become
The hole location in hole tilts and larger deflection, deviation occur for the verticality of drilling rod and center, this is because net in too small hole location
Rock stratum away from lower formation is in thin-walled high-wall shape, and axial rigidity is smaller, can not be provided when rotary drilling rig drills for drilling rod enough
Constraint and supporting role, compared to being that therefore drilling rod easily tends to the hole location of pore-forming and inclines weak location for undisturbed formation
Tiltedly, deviation.The cellular rock stratum area that hole location clear distance L is formed when excessive is larger, and in subsequent punching, then target efficiency is lower,
Reduce integral construction progress.
In step (3), percussive drill punching hole diameter D2 is greater thanTo guarantee 3 He of the first punching point
Second punching point 4 will can all be covered like honeycomb rock stratum, avoid effectively being overlapped generation triangle zone because of punching point
" blind area ".It is met the requirements for power load when ensuring percussive drill operation, and to reach impact job execution efficiency, impacting and apply
The relatively optimization of work workload, cost determines that punching hole diameter D2 is 1.8m~2.5m.Then to power supply for construction when punching hole diameter D2 is excessive
Burden requirement is larger and the construction efficiency of single-point impact operation is lower；When punching hole diameter D2 is too small, then same after drilling
Punching quantity needed for the underwater foundation pit remaining area of size increases, and increases construction operation amount and construction cost.
The ratio between percussive drill punching pitch W and punching hole diameter D2 are 2:3~5:6, be can avoid because of the too small generation of punching pitch W
The rough sledding of " sliding hammer ", or because punching pitch W is excessive, punching point can not effectively be overlapped to generate blind area and reduce to impact effect
Rate.When punching pitch W is too small, i.e., impact operation when impact engagement region it is larger, the hole location of pore-forming is rushed to around
When hitting operation, because low spot occurs in the hole location surrounding, easily occurs " sliding hammer " rough sledding when impact hammer head is impacted, impact hammer head is to hole
Inclination, offset, significantly reduce the stability of impact operation around position.When punching pitch W is excessive, that is, rushing when impacting operation
It is smaller to hit engagement region, in fact it could happen that generate blind area because punching point can not be effectively overlapped, reduce single-point target efficiency.
The present invention excavates the underwater foundation pit of soft rock by using the group technology of rotary drilling rig drilling and percussive drill punching, leads to
It crosses and rotary digging drilling hole diameter D1 and hole location clear distance L, percussive drill punching hole diameter D2 and pitch-row W is reasonably designed and arranged,
A set of efficient, reliable technology and standard criterion are formed, is the construction efficiency and construction precision of the underwater excavation of foundation pit of soft rock
Promotion provide effectively reference and reliable basis.
Embodiment two
In another embodiment of the invention, the main pier of grand bridge project is crossed with the Suining township Lao Chi to Pengxi study ditch farming family
For the underwater excavation of cushion cap, riverbed geology is cobble and weathered mudstone.Cobble overburden cover reaches 3m, weathering mud
Rock intensity reaches 5.1MPa, and rock mass is divided into IV class soft rock.The underwater excavation of foundation pit of cushion cap is drilled using rotary drilling rig and percussive drill
The group technology of punching is constructed, and solves the problems, such as the underwater excavation of foundation pit of soft rock, ensured the smooth sinking of steel boxed cofferdam with
Implantation.It designs underwater 1 range of foundation pit and respectively extends out 1m compared with steel boxed cofferdam surrounding sideline, carry out drilling and punching point in the area
Position is designed and arranged.Rotary drilling rig bore diameter is 2.0m, and hole location clear distance is 0.6m；Percussive drill punching hole diameter is 2.2m,
Pitch-row is 1.8m.
The underwater foundation pit drilling of one of present invention soft rock and punching point arrangement method preferably solve technical background
In the various deficiencies mentioned, and achieve preferable construction effect.Two underwater excavation of foundation pit of cushion cap start to construct certainly, when sharing
106 days, the total 7000m of earthwork3.Construction efficiency and homework precision are highly improved, and steel boxed cofferdam in subsequent construction
Smoothly sink simultaneously implantation.
Above embodiments are only exemplary embodiment of the present invention, are not used in the limitation present invention, protection scope of the present invention
It is defined by the claims.Those skilled in the art can within the spirit and scope of the present invention make respectively the present invention
Kind modification or equivalent replacement, this modification or equivalent replacement also should be regarded as being within the scope of the present invention.
Claims (8)
1. a kind of underwater foundation pit drilling of soft rock and punching point arrangement method, which comprises the following steps:
(1) size and depth of underwater foundation pit are determined according to steel boxed cofferdam size and bed elevation, underwater foundation pit first passes through rotation
It digs drilling machine compartment to drill, forms remaining rock stratum like cellular cylinder, then cutting is impacted by percussive drill, is crushed；
(2) torque specification parameter of rotary drilling rig and the diameter of respective bore are determined according to the soft or hard and integrated degree of geology, then
Stable case when according to bore operation determines the hole location clear distance of drilling.
(3) size like honeycomb cylinder region formed after being drilled according to rotary drilling rig determines that the diameter of percussive drill punching is big
Small, all standing to guarantee remaining area is laid in the occlusion of punching point, according to impact operation degree of stability and single-point target efficiency
Determine the diameter of punching point.
2. the underwater foundation pit drilling of a kind of soft rock according to claim 1 and punching point arrangement method, which is characterized in that step
Suddenly the size range of the underwater foundation pit in (1) respectively extends out 1m~1.5m, the surrounding of underwater foundation pit than steel boxed cofferdam surrounding sideline
Crater wall perpendicular shape from top to bottom.
3. the underwater foundation pit drilling of a kind of soft rock according to claim 1 and punching point arrangement method, which is characterized in that step
Suddenly the range of the bore diameter of rotary drilling rig is 1.5m~2.2m in (2).
4. the underwater foundation pit drilling of a kind of soft rock according to claim 1 and punching point arrangement method, which is characterized in that institute
Stating rotary drilling rig drilling the ratio between hole location clear distance and bore diameter is 1:3~1:4.
5. the underwater foundation pit drilling of a kind of soft rock according to claim 4 and punching point arrangement method, which is characterized in that institute
It states drilling point and mode is evenly arranged using vertical, horizontal, the drilling hole location diameter and clear distance of same row and same row are all the same.
6. the underwater foundation pit drilling of a kind of soft rock according to claim 1 and punching point arrangement method, which is characterized in that institute
Percussive drill punching hole diameter is stated to be greater thanWherein, D1 is bore diameter, and L is drilling hole location clear distance.
7. the underwater foundation pit drilling of a kind of soft rock according to claim 6 and punching point arrangement method, which is characterized in that institute
Stating punching point diameter is 1.8m~2.5m.
8. the underwater foundation pit drilling of a kind of soft rock according to claim 1 and punching point arrangement method, which is characterized in that institute
Stating the ratio between percussive drill punching pitch and punching hole diameter is 2:3~5:6.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910427674.2A CN110130393A (en) | 2019-05-22 | 2019-05-22 | A kind of underwater foundation pit drilling of soft rock and punching point arrangement method |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910427674.2A CN110130393A (en) | 2019-05-22 | 2019-05-22 | A kind of underwater foundation pit drilling of soft rock and punching point arrangement method |
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| CN110130393A true CN110130393A (en) | 2019-08-16 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201910427674.2A Pending CN110130393A (en) | 2019-05-22 | 2019-05-22 | A kind of underwater foundation pit drilling of soft rock and punching point arrangement method |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113153384A (en) * | 2021-03-24 | 2021-07-23 | 中交路桥建设有限公司 | Construction method for deep-buried subway station under rock geology |
| CN113502863A (en) * | 2021-08-11 | 2021-10-15 | 金山 | Foundation ditch vertical road excavation device for construction |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006194031A (en) * | 2005-01-17 | 2006-07-27 | Ps Mitsubishi Construction Co Ltd | Pillar construction method |
| CN102392458A (en) * | 2011-10-17 | 2012-03-28 | 中铁一局集团有限公司 | Piling beam cofferdam construction method used for bare rock foundation construction in water |
| CN108179759A (en) * | 2017-12-29 | 2018-06-19 | 重庆华力建设有限公司 | The underwater drill core slotting of driftway is without bottom sealing method |
| CN109610494A (en) * | 2018-11-30 | 2019-04-12 | 福建建中建设科技股份有限公司 | A kind of embedding rock construction technology of large-diameter pile foundation |
-
2019
- 2019-05-22 CN CN201910427674.2A patent/CN110130393A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006194031A (en) * | 2005-01-17 | 2006-07-27 | Ps Mitsubishi Construction Co Ltd | Pillar construction method |
| CN102392458A (en) * | 2011-10-17 | 2012-03-28 | 中铁一局集团有限公司 | Piling beam cofferdam construction method used for bare rock foundation construction in water |
| CN108179759A (en) * | 2017-12-29 | 2018-06-19 | 重庆华力建设有限公司 | The underwater drill core slotting of driftway is without bottom sealing method |
| CN109610494A (en) * | 2018-11-30 | 2019-04-12 | 福建建中建设科技股份有限公司 | A kind of embedding rock construction technology of large-diameter pile foundation |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113153384A (en) * | 2021-03-24 | 2021-07-23 | 中交路桥建设有限公司 | Construction method for deep-buried subway station under rock geology |
| CN113502863A (en) * | 2021-08-11 | 2021-10-15 | 金山 | Foundation ditch vertical road excavation device for construction |
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Application publication date: 20190816 |