CN107806350B - A kind of submerged tunnel the minimum depth determines method - Google Patents
A kind of submerged tunnel the minimum depth determines method Download PDFInfo
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- CN107806350B CN107806350B CN201710894330.3A CN201710894330A CN107806350B CN 107806350 B CN107806350 B CN 107806350B CN 201710894330 A CN201710894330 A CN 201710894330A CN 107806350 B CN107806350 B CN 107806350B
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- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F17/00—Methods or devices for use in mines or tunnels, not covered elsewhere
Abstract
The invention discloses a kind of submerged tunnel the minimum depths to determine method, consider the Scheme of Strengthening in submerged tunnel design process and influence of the construction segment partition scheme to edpth of tunnel in work progress, the vertical section in tunnel is primarily determined according to the gradient of the wiring condition at submerged tunnel engineering both ends and route first, then select the key sections in tunnel, calculate the minimum depth that reinforcing condition ShiShimonoseki key section guarantees safety for tunnel engineering, while calculating the water percolating capacity of operation phase after tunnel reinforcement, when calculating gained water percolating capacity less than tunnel operation phase water percolating capacity control standard, identified buried depth is the minimum depth in tunnel.In the minimum depth for determining tunnel, all key sections in bed rearrangement tunnel are both needed to meet the requirement of the minimum depth.The present invention can also suitably reduce project cost under the premise of guaranteeing safety for tunnel engineering.
Description
Technical field
The present invention relates to a kind of determination methods of submerged tunnel the minimum depth, and in particular to a kind of tunneling mining method construction
The method of submerged tunnel the minimum depth.
Background technique
The buried depth of submerged tunnel is very big to the construction of engineering and Influence to operation, be influence tunnel cost and safety it is most important
One of design parameter.Edpth of tunnel is bigger, and wiring needed for tunnel two sides is longer, and project cost sharply increases, and unfavorable
Linking in tunnel and two sides existing line；Edpth of tunnel is more shallow, and the risk that constructing tunnel generates landslide gushing water is higher, operation
The pumping effluent cost in stage tunnel can also sharply increase.
The determination method of submerged tunnel boring construction the minimum depth is mainly the following both at home and abroad at present.
(1) Koi carp method.Japanese minimum water yield method is the determination submerged tunnel rock cover thickness being widely adopted
One of method.For specific geological conditions and determine tunnel excavation section configuration, the method be under the seawater of given depth,
Corresponding overlying strata thickness is the rock cover thickness of economic security when Tunnel Seepage minimum.
(2) Norway's empirical method.Norway obtains the warp of submerged tunnel the minimum depth according to built seabed tunnel experience, statistics
Curve is tested, and by comparing preferable country rock and poor country rock respectively, it is determined that submerged tunnel minimum overlying rock thickness
With sea water advanced relationship.
(3) water coal-mining method is pushed up.Use for reference the safe water-proof coal column method for determining height of domestic underwater mining.Safe water-proof coal column
Minimum constructive height should be greater than water flowing fractured zone (the tunnel surrounding zone of fracture) highly the sum of with protective layer thickness, safe water-proof coal column
The determination of height is determined using empirical equation.
(4) least displacement method.This method thinks vault sinking amount most and can reflect surrouding rock deformation caused by tunnel excavation and steady
Qualitative situation, for submerged tunnel section, with the increase of overburden cover, crown displacement is first to reduce, rear to increase, and is existed
Minimum value, therefore, corresponding cladding thickness is exactly reasonable minimum vertex-covering thickness degree when by crown displacement minimum.
(5) Analytical hierarchy process.This method is that one group of expert is asked to carry out the factor for influencing submerged tunnel the minimum depth
Evaluation, according to the judgement of expert, provides judgment weight, obtains the importance factor of the minimum depth, provide distinct methods
Weight, after weighted analysis finally determine submerged tunnel the minimum depth.
(6) weight-function method.This method is determined not according to the determination method of existing different submerged tunnel the minimum depths first
With the respective buried depth of method, then considers the different weights of distinct methods, finally determine final tunnel the minimum depth, provide
0.5 weight of numerical computation, top 0.3 weight of hydromining coal value and minimum 0.2 weight of water burst magnitude, aggregative weighted determine that minimum is buried
It is deep.
On the whole, at present both at home and abroad the determination method of submerged tunnel the minimum depth mainly based on engineering experience method, and
It is aided with numerical value appropriate to calculate, do not account for the reinforcement measure in submerged tunnel design during the determination of buried depth mostly and applies
Influence of the work method to construction safety causes determining submerged tunnel buried depth bigger than normal, and document [7] is proposed based on engineering measure
Submerged tunnel the minimum depth determines method, but the wherein submerged tunnel safety using numerical computation method to engineering measure is considered
Calculating analysis is carried out, is not easy to field engineering application, and its computational accuracy is influenced by computation model and calculating parameter, it can not
Meet the fast-developing needs of China's submerged tunnel construction.
The determination method of existing submerged tunnel the minimum depth is the minimum depth for being primarily based on empirical method and determining tunnel,
The design for then carrying out tunnel structure and tunnel two sides wiring position, edpth of tunnel really timing do not consider reinforcement measure and
The influence of arrangement and method for construction.The submerged tunnel the minimum depth for developing the novel consideration reinforcing coefficient of one kind and blocking factor determines method
It has been to be badly in need of.
Bibliography:
[1] Lv Ming,E, Nilsen B, Melby K. Norwegian Experience in Subsea Tunnelling Chinese Journal of Rock Mechanics and Engineering
.2005；24(23):4219-4225.
[2] Li Shucai, Xu Bangshu, Ding Wantao wait the weight-function method ground power of method for minimum rock cover above submarine tunnel
It learns .2009,30 (4): 989-996
[3]Li Xibing,Li Diyuan,Liu Zhixiang.Determination of the minimum
thickness of crown pillar for safe exploitation of a subsea gold mine based
on numerical modelling.International Journal of Rock Mechanics&Mining
Sciences.2013,57:42–56
[4] Japanese plum sincere feeling, Li Shucai, Zhang Jingwei wait numerical method to determine that method for minimum rock cover above submarine tunnel is studied
[J] geotechnical engineering journal .2006,28 (10): 1304-1308
[5] Japanese plum sincere feeling, Zhang Jingwei, Li Shucai wait Displacement convergence [J] rock of method for minimum rock cover above submarine tunnel
Soil mechanics .2007,28 (7): 1443-1447
[6] step analysis decision-making technique of Zhang Yu, Zhou Jiannan, Ji Chong the seabed tunnel rock covering thickness based on group
[J] geotechnical engineering journal .2010,32 (4): 638-644
[7] Shi Chenghua, Song Yi, Peng Limin etc., a kind of submerged tunnel the minimum depth based on control methods of projects are determining
Method, national inventing patent: ZL 201210110410.2
Summary of the invention
The technical problem to be solved by the present invention is in view of the shortcomings of the prior art, provide a kind of submerged tunnel the minimum depth
It determines method, the determination of existing submerged tunnel the minimum depth (overburden cover) is overcome only to consider the intensity of tunnel surrounding itself,
It is difficult to consider that tunnel reinforcement measure and arrangement and method for construction determine the defect influenced to safety for tunnel engineering and buried depth.
In order to solve the above technical problems, the technical scheme adopted by the invention is that: a kind of submerged tunnel the minimum depth is determining
Method, this method mainly realize process are as follows: preliminary true according to the wiring condition at submerged tunnel engineering both ends and the gradient of route
Determine the vertical section in tunnel, then select the key sections in tunnel, guarantees under the conditions of consideration reinforcing being calculated as follows and piecemeal of constructing
The minimum depth h of safety for tunnel engineering:
Wherein a is the practical the thickness of the layer of tunnel top, and s is rock covering thickness, and H is tunnel top head height,
Unit is m；B is tunnel width, unit m；N is the excavation block count in cross section during constructing tunnel；fjFor tunnel after reinforcing
The weighting Pu Shi strength factor of basement rock at the top of road.
fjCalculation formula it is as follows:
Wherein, s1、f1The height and Pu Shi strength factor of rock stratum, s are reinforced for tunnel top2、f2It is unguyed for tunnel top
The height and Pu Shi strength factor of rock stratum.
The key sections include that the most deep section of water level, the smallest section of underwater buried depth, submerged tunnel span are maximum
Section and the worst section of underwater wall rock condition.
Also consider the influence that phase water percolating capacity is runed it after tunnel reinforcement when determining the minimum depth of submerged tunnel, under
Formula calculates the water percolating capacity Q that the phase is runed after submerged tunnel is reinforced:
Wherein, H is tunnel top head height, klFor first branch infiltration coefficient；kgFor injecting cement paste infiltration coefficient；krFor country rock
Infiltration coefficient, r0For lining cutting internal diameter, r1For lining cutting outer diameter, rgFor Grouting Circle radius, r2For tunnel radius and overburden cover it
With；
When calculating gained water percolating capacity Q less than tunnel operation phase water percolating capacity control standard, identified buried depth is tunnel
The minimum depth increase tunnel reinforcement circle when calculating resulting water percolating capacity Q and being greater than the control standard of tunnel operation phase water percolating capacity
Thickness or increase tunnel buried depth, re-start calculatings, until meet tunnel run phase water percolating capacity control standard until.
It is 0.432m that the control standard of submerged tunnel operation phase water percolating capacity, which is the daily average water percolating capacity in every linear meter(lin.m.) tunnel,3。
All key sections in bed rearrangement tunnel are all satisfied the requirement of the minimum depth.
In the present invention, reinforcement measure is advanced curtain-grouting and per-fore pouring liquid with small pipe, to form slip casting in tunnel perimeter
Fixing collar, working measure refer to the excavation span that tunnel is reduced using the method for partial excavation.
Compared with prior art, the advantageous effect of present invention is that: the present invention is first according to the wiring of tunnel two sides
Condition primarily determines the vertical section in tunnel, then considers the influence of reinforcement measure and arrangement and method for construction, by reinforcing coefficient and piecemeal
Coefficient determines the minimum depth of tunnel key section, determine therefrom that the final buried depth in tunnel, under water tunnel the minimum depth
The effect of true timing considerations reinforcement measure and arrangement and method for construction reduces submerged tunnel by the use of reinforcement measure and arrangement and method for construction
The minimum depth, shorten the length of submerged tunnel, convenient for the linking of the same existing road in tunnel two sides, to give full play to the friendship in tunnel
It is logical to discongest function, under the premise of guaranteeing safety for tunnel engineering, suitably reduce project cost.
Detailed description of the invention
Fig. 1 is the schematic diagram that submerged tunnel the minimum depth of the present invention determines method；
Water seepage of tunnel amount calculates schematic diagram under the conditions of the position Fig. 2 present invention reinforces；
In figure: 1-height of water level, 2-riverbeds, 3-tunnel reinforcement circles, 4-tunnels, 5-tunnel-liners, 6-country rocks, A,
B-tunnel's entrance and exit, h-submerged tunnel the minimum depth.
Specific embodiment
The present invention comprehensively considers the construction of submerged tunnel under the conditions of tunnel perimeter country rock pre-reinforcement and different arrangement and method for construction
Safety, the wiring condition at tunnel both ends, tunnel water percolating capacity determine the minimum depth in tunnel.First according to submerged tunnel work
The wiring condition at journey both ends and the gradient of route primarily determine the vertical section in tunnel, then select the key sections in tunnel, meter
Calculate the minimum depth for guaranteeing safety for tunnel engineering under the conditions of considering to reinforce and constructing piecemeal.Simultaneously in the minimum for determining submerged tunnel
The influence for runing it phase water percolating capacity after tunnel reinforcement is also considered when buried depth, calculates the water percolating capacity that the phase is runed after tunnel reinforcement, when
When calculating gained water percolating capacity less than tunnel operation phase water percolating capacity control standard, identified buried depth is the minimum depth in tunnel,
When calculating control standard of the resulting water percolating capacity greater than tunnel operation phase water percolating capacity, increase thickness or the increasing of tunnel reinforcement circle
The buried depth for adding tunnel re-starts calculating, until meeting the control standard of tunnel operation phase water percolating capacity.Determining tunnel
All key sections in bed rearrangement tunnel are both needed to meet the requirement of the minimum depth when the minimum depth.
(1) referring to Fig. 1, according to the wiring condition (grounding point position A and B) of submerged tunnel engineering two sides and the slope of route
Degree primarily determines the vertical section in tunnel.
(2) according to the tunnel profile primarily determined, the key sections for choosing tunnel are analyzed, and specifically include water level most
Deep section, the smallest section of underwater buried depth, the maximum section of submerged tunnel span and the worst section of underwater wall rock condition.
(3) tunnel specifically advanced curtain-grouting and per-fore pouring liquid with small pipe reinforcing side are determined according to the wall rock condition in tunnel
Case and grouting and reinforcing parameter, and determine that specific constructing tunnel excavates segment partition scheme.
(4) calculate consider reinforce and construction piecemeal under the conditions of guarantee safety for tunnel engineering the minimum depth, specifically use with
Lower method is calculated:
Wherein a is the practical the thickness of the layer of tunnel top, and s is rock covering thickness, and H is tunnel top head height
(m)；B is tunnel width (m)；N is the excavation block count in cross section during constructing tunnel；fjFor tunnel top basement rock after reinforcing
Weighting Pu Shi strength factor, value are as follows:
Wherein s1、f1The height and Pu Shi strength factor of rock stratum, s are reinforced for tunnel top2、f2It is unguyed for tunnel top
The height and Pu Shi strength factor of rock stratum.
(4) on the basis of tunnel the minimum depth determined above, referring to fig. 2, the infiltration of operation phase after tunnel reinforcement is calculated
Whether water meets tunnel operation phase water percolating capacity control standard, is specifically calculated as the following formula:
Wherein Q is water percolating capacity, and H is underground flood peak height, klFor first branch infiltration coefficient；kgFor injecting cement paste infiltration coefficient；krFor
Country rock infiltration coefficient, r0For lining cutting internal diameter, r1For lining cutting outer diameter, rgFor Grouting Circle radius, r2For tunnel radius and overburden cover
The sum of.
(5) judge whether the water percolating capacity of tunnel operation phase after reinforcing meets the daily average water percolating capacity in every linear meter(lin.m.) tunnel and be
0.432m3Operational requirements, when calculate gained water percolating capacity be less than tunnel operation phase water percolating capacity control standard when, identified buried depth
The as the minimum depth in tunnel increases tunnel when calculating control standard of the resulting water percolating capacity greater than tunnel operation phase water percolating capacity
The thickness of road fixing collar or the buried depth for increasing tunnel, re-start calculating, the control until meeting tunnel operation phase water percolating capacity
Until standard.
(6) when bed rearrangement tunnel, all key sections are both needed to meet the requirement of the minimum depth, the buried depth in identified tunnel
The minimum depth as under the conditions of submerged tunnel reinforcing.
Claims (6)
1. a kind of submerged tunnel the minimum depth determines method, which is characterized in that this method mainly realizes process are as follows: according to underwater tunnel
The wiring condition at road engineering both ends and the gradient of route, primarily determine the vertical section in tunnel, and the key for then selecting tunnel is disconnected
The minimum depth h for guaranteeing safety for tunnel engineering under the conditions of considering to reinforce and constructing piecemeal is calculated as follows in face:
Wherein a is the practical the thickness of the layer of tunnel top, and s is rock covering thickness, and H is tunnel top head height, unit
For m；B is tunnel width, unit m；N is the excavation block count in cross section during constructing tunnel；fjFor tunnel top after reinforcing
The weighting Pu Shi strength factor of portion's basement rock.
2. submerged tunnel the minimum depth according to claim 1 determines method, which is characterized in that fjCalculation formula it is as follows:
Wherein, s1、f1The height and Pu Shi strength factor of rock stratum, s are reinforced for tunnel top2、f2For the unguyed rock stratum of tunnel top
Height and Pu Shi strength factor.
3. submerged tunnel the minimum depth according to claim 1 determines method, which is characterized in that the key sections include
The most deep section of water level, the smallest section of underwater buried depth, the maximum section of submerged tunnel span and underwater wall rock condition are worst
Section.
4. submerged tunnel the minimum depth according to claim 1 determines method, which is characterized in that determine submerged tunnel most
The influence for runing it phase water percolating capacity after tunnel reinforcement is also considered when small buried depth, is calculated after submerged tunnel is reinforced and is runed using following formula
The water percolating capacity Q of phase:
Wherein, H is tunnel top head height, klFor first branch infiltration coefficient；kgFor injecting cement paste infiltration coefficient；krFor country rock infiltration
Coefficient, r0For lining cutting internal diameter, r1For lining cutting outer diameter, rgFor Grouting Circle radius, r2For the sum of tunnel radius and overburden cover；
When calculate gained water percolating capacity Q be less than tunnel operation phase water percolating capacity control standard when, identified buried depth be tunnel most
Small buried depth increases the thickness of tunnel reinforcement circle when calculating control standard of the resulting water percolating capacity Q greater than tunnel operation phase water percolating capacity
Degree or the buried depth for increasing tunnel, re-start calculating, until meeting the control standard of tunnel operation phase water percolating capacity.
5. submerged tunnel the minimum depth according to claim 4 determines method, which is characterized in that submerged tunnel runs phase infiltration
The control standard of water is that the daily average water percolating capacity in every linear meter(lin.m.) tunnel is 0.432m3。
6. submerged tunnel the minimum depth according to claim 1 determines method, which is characterized in that all keys in bed rearrangement tunnel
Section is all satisfied the requirement of the minimum depth.
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| CN108573095B (en) * | 2018-03-28 | 2020-06-23 | 北京交通大学 | River-crossing sea shield tunnel reasonable earth covering setting method based on tunneling safety |
| CN108842821B (en) * | 2018-06-29 | 2020-08-25 | 山东大学 | Calculation method for reasonable buried depth of submarine tunnel constructed by drilling and blasting method |
| CN109026144B (en) * | 2018-07-27 | 2019-07-05 | 北京交通大学 | A kind of seabed tunnel active control type guarded drainage System Design method and system |
| CN116244794B (en) * | 2022-12-31 | 2023-12-29 | 中铁隧道勘察设计研究院有限公司 | Calculation method for minimum safe overlying strata thickness of underwater non-blasting undercut tunnel |
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