A kind of flare sidewall horizontal for 8 pilot tunnel PBA engineering methods makes bottom basin shape and freezes sealing
Engineering method
Technical field
The present invention relates to city Deep Underground Space excavation supporting technical fields, more particularly to a kind of city sensitizing range
Freeze waterstop construction process in the station PBA.
Background technique
With the development of process of modernization, public transport, which relies solely on ground space, can no longer meet needs, repair
The inevitable outcome that underground railway is urban development is built, even more alleviation traffic congestion, encourages the requisite measure of bus trip.
So far, China has had a city more than 30 to build subway, with being continuously increased for subway mileage, in depth
Also constantly developing on direction.With gradually increasing for cutting depth, soil body occurrence condition, soil layer property, stress are not
Disconnected variation, underground water is increasingly becoming an important factor for influences is constructed, and how effectively to handle and encounters in work progress
Problem of groundwater is urgent problem to be solved during metro construction.
In modern city, above-ground structures is intensive, and all kinds of pipelines in underground are intensive, can be to building using the method for artificial rainmaking
Object and pipeline cause tremendous influence, moreover, due to urban policy, many cities such as Beijing, in work progress
A large amount of groundwater abstractions will cause huge economic loss, in addition, in face of the status that present city water resource lacks, artificial rainmaking
Method will also result in the waste of water resource.Meanwhile continually developing with Deep Underground Space, traditional dewatering measure is
It is not able to satisfy the precipitation requirement increasingly deepened.Based on this, artificial freezing technology becomes the ground rationally solved in metro construction
The effective way of lower water problems.
Freezing process is to make the water freezing in stratum using artificial cooling technology, natural ground is become frozen soil, and it is strong to increase it
Degree and stability, isolation underground water and underground engineering contact, to carry out pit shaft or underground engineering under the protection of frost wall
The special constructional technique of driving and masonry construction.Earliest be used for Russia's exploitation of gold deposit, after obtained by German engineer for mining pit construction
It obtains patented technology and tends to be mature, be now widely used in the engineerings such as deep basal pit, mine construction.With effective isolation underground
Water, it is adaptable, construction flexibly, green non-pollution the advantages that.It can be seen that freezing process is introduced into urban tunnel construction, close
Understand problem of groundwater of determining, is technically feasible.
But currently without a kind of effective frozen construction engineering method for the city sensitizing range station PBA, do not have yet
Have and combined with the construction at the station PBA, freezing efficiency is undesirable, cannot be formed one closing or it is semi-enclosed freeze wall construction,
An effective frozen construction region can not be formed, low efficiency is freezed, it is long in time limit, and be easy to cause the work holdup existing because of frozen construction
As.
Summary of the invention
It is an object of the invention to overcome the shortcomings of the prior art, specific to 8 pilot tunnel PBA engineering methods, one kind is proposed
The basin shape that flare sidewall horizontal makes bottom freezes sealing engineering method, can be effectively formed frozen structure isolation and excavate waterpower within and outside the region
Connection, reaches sealing purpose.
The purpose of the present invention can be achieved through the following technical solutions:
A kind of flare sidewall horizontal for 8 pilot tunnel PBA engineering methods makes bottom basin shape and freezes sealing engineering method, comprises the following steps:
(1) vertical shaft freezing pipe and Construction of Silo:Construction shaft freezing pipe, vertical shaft frozen structure formed after to lower carry out vertical shaft
It excavates, and water level line vertical shaft inner wall below is added and does waterproof construction;
(2) upper layer transverse passage-way and the construction of upper layer pilot tunnel:Shaft excavation is to predetermined position, to underground structure side in vertical shaft
It constructs upper layer transverse passage-way, after the completion of the adit construction of upper layer, upper layer pilot tunnel of constructing in the transverse passage-way of upper layer;
(3) flare freezes pipe construction:The edge in the outer part in the side pilot tunnel of upper layer pilot tunnel two sides, downwardly and outwardly construction is outer
Incline freezing hole, and flare freezing pipe is inserted into hole;
(4) increase and dig Construction of Silo:Prior to, concurrently with, or after construction procedure (2) or step (3), continued by vertical shaft downward
It is excavated to structure base slab and digs vertical shaft hereinafter, being formed and being increased, and increasing digging vertical shaft inner wall is added and does waterproof construction;
(5) increase to dig transverse passage-way freezing pipe and increase and dig adit construction:Increase increasing to dig to construct in vertical shaft to underground structure side
Transverse passage-way freezing pipe is dug to design length, after increasing digging transverse passage-way frozen structure is formed, is opened from increasing digging vertical shaft to underground structure side
It digs to increase and digs transverse passage-way, and the inner wall for increasing digging transverse passage-way is added and does waterproof construction;
(6) horizontal frozen pipe construction:Increasing the direction construction level freezing hole for digging and extending in transverse passage-way to underground structure,
Horizontal frozen pipe is inserted into hole;
(7) freeze network construction:It lays and connects in vertical freezing pipe and horizontal frozen pipe and freeze pipeline, freeze in length and breadth
Tubular gelation netting network, and open refrigeration plant trial operation;
(8) frost wall is formed:Start refrigeration plant, carry out frozen construction, side wall freezing pipe freezes to form two sidewalls, and level is frozen
Knot pipe, which freezes to form level, makes bottom, is thusly-formed basin shape construction area.
Preferably, construction shaft freezing pipe is in step (1):By ground downwards construction shaft periphery freezing pipe to designing depth
Degree, carries out downwards shaft excavation, and when being excavated to close to phreatic line, construction shaft bottom freezing pipe is to designing depth in vertical shaft
Degree.
Preferably, when carrying out water level line or less shaft excavation, water level line vertical shaft bottom freezing pipe below is cut.
Preferably, increase to dig at the top of transverse passage-way in step (5) and reserve certain thickness overburden layer between underground structure bottom plate.
Preferably, increasing digging transverse passage-way in step (5) and freezing pipe construction includes digging in vertical shaft to apply to underground structure side from increasing
Work, which increases to dig transverse passage-way periphery freezing pipe and increase, digs transverse passage-way end face freezing pipe, and periphery freezing pipe is used to form periphery frost wall, holds
Face freezing pipe is used to form end face frost wall, and periphery frost wall and end face frost wall collectively form increasing and dig adit construction region.
Preferably, one row of horizontal frozen pipe construction, two rows, three rows or more arrange in step (6).
Preferably, it lays in step (7) and connects and freeze pipeline and be specially:Feed liquor is inserted into the freezing pipe constructed
Pipe and liquid back pipe, one end of inlet tube connect liquid distribution pipe, and liquid distribution pipe connects refrigeration plant;One end of liquid back pipe connects collector tube, collection
Liquid pipe connects the refrigeration plant, and circuit, flare freezing pipe are freezed in liquid distribution pipe, inlet tube, liquid back pipe, collector tube, refrigeration plant formation
It is collectively formed with horizontal frozen pipe and freezes network.
Preferably, frozen construction is specially in step (8):Airtight test is carried out to freezing pipe, is started after passed examination
Refrigeration plant recycles refrigerant in the freezing pipe, by measuring and analyzing embedding in advance temperature tube and hydrology pipe data, really
Frost wall mean temperature and thickness are determined, until meeting design requirement.
Preferably, refrigerant is low temperature CaCl2 solution, liquid nitrogen or cooling water.
Preferably, also there are step (9), refrigerant recovering and freezing pipe processing:After the completion of Underground Construction, extraction is freezed
Refrigerant in pipe blocks freezing pipe nozzle, and freezing hole aperture is backfilled and blocked.
The beneficial effect of advantages of the present invention and generation:
(1) engineering method is effectively integrated with PBA engineering method, is directly constructed flare freezing hole, is not required to by upper layer side pilot tunnel
Other constructing pilot tunnel is wanted, cost is not increased, does not influence the crucial duration.
(2) 8 pilot tunnel PBA engineering methods are directed to, using side wall flare, basin shape construction area interior main body structural excavation region is away from freezing
Wall certain distance excavates hydraulic connection within and outside the region in effective isolation, reaches sealing purpose and freeze meanwhile, it is capable to avoid excavating
Soil.
(3) on the basis of existing vertical shaft, continue to excavate downwards to increase to dig vertical shaft and increase and dig transverse passage-way, freeze to form basin bottom jelly
Bottom plate is tied, independent construction shaft is not needed, not will increase too many project amount, provide further relative savings of cost, do not influence the crucial duration.
(4) when construction level makes bottom, by the established vertical shaft of PBA engineering method, existence conditions is made full use of, do not will increase too
More project amounts, and the seal water structure at bottom, the frozen construction of early period and later period are made in underground structure bottom plate level formed below
The frozen structure of formation does not interfere excavation operation, and the later period without cutting freezing pipe, saves the duration.
(5) increase to dig between transverse passage-way and structure base slab and overburden layer is set, can be effectively prevented and freeze to influence main body excavation area
Domain does not need to excavate frozen soil, not need using construction measure in Winter, while overburden layer enhances the anti-floating for freezing bottom plate.
(6) freezing pipe, which stays in, is used as group's anchor in the soil body, play the role of strengthening stratum, waste utilization kills two birds with one stone.
(7) for the engineering method combination PBA engineering method based on freezing, freezing pipe can have waste utilization, ground in later period strengthening stratum
It is lauched zero extraction, and most of frozen construction process is carried out in underground, there is no pollution, put outside zero, adaptable, construction
Flexibly, the advantages that green non-pollution.
Detailed description of the invention
Fig. 1 is 1 work progress schematic diagram one of the embodiment of the present invention;
Fig. 2 is 1 work progress schematic diagram two of the embodiment of the present invention;
Fig. 3 is 1 work progress schematic diagram three of the embodiment of the present invention;
Fig. 4 is 1 work progress schematic diagram four of the embodiment of the present invention;
Fig. 5 is mixture proportioning in construction of the present invention;
Fig. 6 is vertical shaft frozen construction floor plan of the present invention;
Fig. 7 is construction process figure of the present invention.
In figure:1. vertical shaft;2. upper layer transverse passage-way;3. upper layer pilot tunnel;4. flare freezing pipe;5. flare side wall;It is erected 6. increasing and digging
Well;Transverse passage-way is dug 7. increasing;8. horizontal frozen pipe;9. level makes bottom;10. crown beam;11. overburden layer;12. lower layer's pilot tunnel;13. ground
Flowering structure outer profile;14. shaft perimeter freezing pipe;15. vertical shaft bottom freezing pipe;16. periphery frost wall;17. bottom frost wall.
Specific embodiment
In order to make the object, technical scheme and advantages of the embodiment of the invention clearer, below in conjunction with the embodiment of the present invention
In attached drawing, technical scheme in the embodiment of the invention is clearly and completely described, it is clear that described embodiment is
A part of the embodiment of the present invention, instead of all the embodiments.Based on the embodiments of the present invention, those of ordinary skill in the art
Every other embodiment obtained without creative efforts, shall fall within the protection scope of the present invention.
In the description of the present invention, it is to be understood that, term " center ", " longitudinal direction ", " transverse direction ", "front", "rear",
The orientation or positional relationship of the instructions such as "left", "right", "vertical", "horizontal", "top", "bottom" "inner", "outside" is based on attached drawing institute
The orientation or positional relationship shown, is merely for convenience of description of the present invention and simplification of the description, rather than the dress of indication or suggestion meaning
It sets or element must have a particular orientation, be constructed and operated in a specific orientation, therefore should not be understood as protecting the present invention
The limitation of range.
It should also be noted that, term "comprises/comprising", " by ... form " or its any other variant be intended to
Non-exclusive inclusion, so that the product, equipment, process or the method that include a series of elements not only include those elements,
And when needing can also include other elements that are not explicitly listed, or further include for this product, equipment, process or
The intrinsic element of method.In the absence of more restrictions, by sentence " including/include ... ", " by ... form " limit
Fixed element, it is not excluded that there is also other identical elements in product, equipment, process or the method for including the element.
Embodiment of the present invention is described further in detail below.
Referring to attached drawing 1-4, a kind of flare sidewall horizontal for 8 pilot tunnel PBA engineering methods of the invention makes bottom basin shape and freezes to stop
Water conservancy project method, comprises the following steps:
(1) vertical shaft freezing pipe and Construction of Silo:Construction shaft freezing pipe, vertical shaft frozen structure formed after to lower carry out vertical shaft
It excavates, and water level line vertical shaft inner wall below is added and does waterproof construction;Excavating shaft can select scene suitable according to execution conditions
Construction technology.
Referring specifically to attached drawing 6, construction shaft freezing pipe is:By ground, construction shaft periphery freezing pipe 14 is deep to design downwards
Degree, carries out downwards shaft excavation, and when being excavated to close to phreatic line, construction shaft bottom freezing pipe 15 is to design in vertical shaft
Depth, vertical shaft frozen structure continue to carry out shaft excavation downwards after being formed.Periphery freezing pipe 14 is used to form periphery frost wall 16,
Bottom freezing pipe 15 is used to form bottom frost wall 17, by periphery frost wall 16 and bottom frost wall 17, forms a side
With the closed cylindrical structure in bottom surface, which can block hydraulic connection inside and outside vertical shaft, to provide the perpendicular of a safety
Well construction region.
Since shaft perimeter frost wall can be destroyed in construction in later period lower layer transverse passage-way, lead to water burst, therefore to water level
Line vertical shaft inner wall below, which adds, does waterproof construction.
When continuing to carry out downwards shaft excavation below water level line, vertical shaft bottom freezing pipe 15 interferes to excavate, to water level line
Vertical shaft bottom freezing pipe below is cut, and side cutting edge carries out excavation operation.
(2) upper layer transverse passage-way 2 and upper layer pilot tunnel 3 are constructed:When shaft excavation to upper layer transverse passage-way position, to side in vertical shaft
Surface construction upper layer transverse passage-way, after the completion of the adit construction of upper layer, four upper layer pilot tunnels 3 of constructing in the transverse passage-way of upper layer;It leads on upper layer
Work surface of the hole as later period main structure construction, unearthed channel when upper layer transverse passage-way is as main structure construction.
(3) flare freezing pipe 4 is constructed:The edge in the outer part in the side pilot tunnel of 4, upper layer pilot tunnel two sides, is downwardly and outwardly applied
Work flare freezing hole is inserted into flare freezing pipe in hole.
Due to 8 each 4 pilot tunnel of the upper and lower layer of pilot tunnel PBA engineering method, and the corresponding arrangement in pilot tunnel position up and down, considering the side of freezing
When case, due to the presence of lower pilot tunnel, the condition without vertical freezing hole of directly constructing, therefore 8 pilot tunnel PBA engineering methods are directed to, this
Invention pointedly proposes a kind of practicable side wall freeze design scheme, is effectively combined with PBA engineering method, freezing hole is by top
Side pilot tunnel is directly constructed, and other constructing pilot tunnel is not needed, and saves construction cost, does not influence the crucial duration.
Flare freezing pipe, which protrudes into, reserves certain length in pilot tunnel, freeze pipeline and progress frozen construction for arranging, reserve
Section crown beam 10 reserved location, construct crown beam when with crown beam formed integral structure, fix freezing pipe and freezing pipe played
Protective effect prevents from destroying freezing pipe when soil excavation and structure construction.
(4) increase and dig Construction of Silo:Structure base slab is excavated to downwards by vertical shaft continuation hereinafter, forming increasing digging vertical shaft 6, and to increasing
Digging vertical shaft inner wall, which adds, does waterproof construction;The construction for increasing digging vertical shaft 6 does not conflict with the construction of aforementioned upper layer transverse passage-way and freezing pipe, can
Flexibly carried out with field condition, in order to save the duration, optimum way such as Fig. 7, increase dig vertical shaft 6, increase dig transverse passage-way 7 construction with it is upper
The construction of layer transverse passage-way, upper layer pilot tunnel and flare freezing pipe is synchronous to be carried out.
Increase and dig after the completion of vertical shaft, beats when transverse passage-way freezing pipe is dug in increasing and can be broken in the later period due to increasing digging shaft perimeter frost wall
It is bad, lead to water burst, therefore add to increasing digging vertical shaft inner wall and do waterproof construction.
(5) increase to dig transverse passage-way freezing pipe and increase and dig the construction of transverse passage-way 7:It digs in vertical shaft increasing to underground structure side, passes through
Increase and dig vertical shaft waterproof construction and increase digging shaft perimeter frost wall, construction, which increases, digs transverse passage-way freezing pipe to design length, and it is horizontal logical to increase digging
After road frozen structure is formed, increase digging transverse passage-way from increasing to dig vertical shaft and excavate to underground structure side.
Increasing digging transverse passage-way and freezing pipe construction includes digging to construct to underground structure side in vertical shaft from increasing to increase digging transverse passage-way periphery
Transverse passage-way end face freezing pipe is dug in freezing pipe and increasing, and periphery freezing pipe is used to form periphery frost wall, and end face freezing pipe is used to form
End face frost wall, periphery frost wall and end face frost wall collectively form increasing and dig adit construction region.
Phreatic line is in hereinafter, after the completion of increasing digging adit construction due to increasing digging transverse passage-way, and the later period sets horizontal jelly
Knot pipe can destroy periphery frost wall, lead to water burst, therefore add to the inner wall for increasing digging transverse passage-way and do waterproof construction, to meet underground water
Bit line construction requirement below.
Increase to dig at the top of transverse passage-way and reserve certain thickness overburden layer 11 between structure base slab, by excavating region in main body
It is made with level and retains overburden layer between bottom, the level that horizontal frozen formation can be effectively prevented makes bottom thickness effect main body excavation area
Domain does not need to excavate frozen soil, not need using construction measure in Winter, while the presence of overburden layer can also enhance level well
Make the anti-floating at bottom.
(6) horizontal frozen pipe construction:Increasing the direction construction level freezing hole for digging and extending in transverse passage-way to underground structure,
Horizontal frozen pipe 8 is inserted into hole.
It is to excavate area peripheral edge in underground structure to freeze to form curtain that existing basin shape, which freezes measures of preventing water, i.e. side wall freezes
Wall, while being excavated in regional scope in underground structure and setting densely covered vertical freezing pipe, freezing to be formed by vertical freezing pipe has
Certain thickness bottom seal water structure is thusly-formed side wall and bottom is closed freezes water sealing structure, but this structure needs to exist
Frozen construction in region is excavated, the excavation operation that region is excavated in frozen construction should stop, this necessarily causes to delay underground
The normal excavation of the soil body in structural region, more influence underground structure normal construction, and frozen structure formed after continue to open downwards
When excavation construction, it must be synchronized with the progress of excavation and cutting operation is carried out to freezing pipe, this also extends construction to a certain degree
Duration.The present invention excavates the following construction level freezing pipe in region in underground structure, and frozen structure and excavation region are non-interference, has
Effect avoids frozen construction process and frozen structure formed after influence to Underground Construction.
Wherein horizontal frozen pipe construction is a row or multi-row, this depends on frozen thickness required for basin bottom, it is generally the case that
Single to freeze 1.5 meters, two rows freeze 3 meters or so, and three rows freeze 4 meters of thickness, are ensuring requirement to freezing efficiency and are comprehensively considering construction
Under the premise of cost, preferred levels freezing hole construction two rows or three rows.
Referring to attached drawing 5, freezing pipe is arranged on horizontal and vertical the region that cover underground main structure comprehensively, that is, wants
Underground structure outer profile 13 is covered, underground structure is underground station, and should be than the region where the main structure of underground to cross
To with longitudinal extension a certain range, so ensure to meet the requirement of underground structure boundary of works area, while being avoided that frozen region again
The region for extending to structure construction avoids excavating frozen soil and winter construction.
(7) freeze network construction:It is laid in flare freezing pipe and horizontal frozen pipe and freezes pipeline, network is freezed in formation.
It wherein lays and freezes pipeline and be specially:Inlet tube and liquid back pipe, inlet tube are inserted into the freezing pipe constructed
One end connect liquid distribution pipe, liquid distribution pipe connect refrigeration plant;One end of liquid back pipe connects collector tube, and collector tube connects the refrigeration
It stands, what liquid distribution pipe, inlet tube, liquid back pipe, collector tube, refrigeration plant formation were closed freezes circuit, flare freezing pipe and horizontal frozen
Pipe, which is collectively formed, freezes network.
(8) frost wall is formed:Start refrigeration plant, carry out frozen construction, flare freezing pipe 4 freezes to form flare side wall 5, water
Flat freezing pipe 8 freezes to form the horizontal bottom plate that freezes, i.e. level makes bottom 9, is thusly-formed basin shape construction area.
After frost wall is formed, the manually digging hole operation of skirt piles, the following soil excavation of level of ground water, 4 lower layer's pilot tunnels are carried out
12 and main structure construction.
Frozen construction is specially:Airtight test is carried out to freezing pipe, starts refrigeration plant after passed examination, makes refrigerant in institute
Circulation in freezing pipe is stated, by measuring and analyzing preparatory embedding temperature tube and hydrology pipe data, determines frost wall mean temperature
And thickness, until meeting design requirement.
The refrigerant is low temperature CaCl2Solution, liquid nitrogen or cooling water.
After the completion of Underground Construction, the scheme that natural thaw or artificial quick-thawing can be used restores Groundwater Flow,
The refrigerant in freezing pipe is extracted, blocks freezing pipe nozzle, and freezing hole aperture is backfilled and blocked.Freezing pipe stays in soil layer
It is interior, with soil body collective effect, strengthening stratum can be played the role of in the later period.
After the completion of Underground Construction, necessary backfill treatment measures are carried out, such as block pilot tunnel, backfill transverse passage-way, backfill
Vertical shaft so completes the construction of entire underground structure.
Above example, only with for the preferable specific embodiment of the present invention, but protection scope of the present invention is not limited in
This, anyone skilled in the art, within the technical scope of the present disclosure, it is contemplated that variation or equally replace
It changes, should all cover within the protection scope of the present invention.Therefore, protection scope of the present invention should be with the protection of claims
Subject to range.