CN104879131A - Large-span tunnel excavation method for upper soft and lower hard compound strata - Google Patents

Large-span tunnel excavation method for upper soft and lower hard compound strata Download PDF

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Publication number
CN104879131A
CN104879131A CN201510228004.XA CN201510228004A CN104879131A CN 104879131 A CN104879131 A CN 104879131A CN 201510228004 A CN201510228004 A CN 201510228004A CN 104879131 A CN104879131 A CN 104879131A
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tunnel
excavation
predicament
bar
embarrassing situation
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CN201510228004.XA
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Chinese (zh)
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CN104879131B (en
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邹金杰
章立峰
潘乘浪
胡贤国
闫自海
彭加强
朱双厅
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中国电建集团华东勘测设计研究院有限公司
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Abstract

The present invention relates to a large-span tunnel excavation method for upper soft and lower hard compound strata. The present invention aims at providing a large-span tunnel excavation method for upper soft and lower hard compound strata so as to ensure large-span tunnel construction safety for the upper soft and lower hard compound strata, accelerate the construction progress and shorten the construction period. The technical scheme is that a tunnel is divided into upper and lower steps for excavation by the method, and the steps are as follows: a, determining a boundary of the upper soft and lower hard strata of an excavation surface according to geological prospecting data; b, constructing the upper step by using the center diaphragm method; c, constructing the lower step by using the method of reserving core soil; d, lagging the lower step with 2-3m headings at two sides; e, arranging earthwork cloth and an EVA waterproof board on a surface of a lower step inverted arch preliminary bracing, and pouring an inverted arch second lining; and f, dismounting a center diaphragm temporary bracing of the upper step and a temporary inverted arch of the upper step with segments, and pouring a pavement lining close to a preliminary bracing of the upper step and preliminary bracings of the headings at the two sides of the lower step. The large-span tunnel excavation method is applied to the technical field of tunnel construction.

Description

The longspan tunnel excavation method of upper soft lower hard compound stratum

Technical field

The present invention relates to a kind of longspan tunnel excavation method of soft lower hard compound stratum.Be applicable to technical field of tunnel construction.

Background technology

In constructing tunnel, excavation method is one of key factor affecting tunnel stabilization, also governs construction speed and the construction costs of engineering simultaneously.For III, IV grade of country rock longspan tunnel, more employing benching tunnelling method construction, have larger working space in hole, be applicable to mechanized construction, speed of application is very fast, but excavation face is large, and country rock relative stability reduces; For V, VI grade of weak surrounding rock, current more employing intersection median septum method (CRD), it is by big cross section being divided into 4 or the construction of 6 light sections, excavated section can be avoided excessive thus formation produced large disturbances, ensure that excavation safety.

But due to the non-homogeneity on stratum, tunnel excavation section more appearance is in soft lower hard compound stratum situation, and namely tunnel cross-section top is Soft Soil Layer, and bottom is harder soil layer or rock, country rock grade V grade often, or even VI grade; Under this formation condition, adopt traditional benching tunnelling method construction or median septum method (CRD) construction that intersects, applicability is poor, the former cannot ensure to top bar construction safety in tunnel, the latter is because of a point multi-section excavation, and excavation face working space is less, cannot realize mechanized construction, and complex procedures, construction speed is slower.

Summary of the invention

The technical problem to be solved in the present invention is: for above-mentioned Problems existing, provides a kind of longspan tunnel excavation method of soft lower hard compound stratum, to guarantee upper-soft lower-hard ground longspan tunnel construction safety, accelerating construction progress, reduction of erection time.

The technical solution adopted in the present invention is: a kind of longspan tunnel excavation method of soft lower hard compound stratum, and tunnel is divided into upper and lower step to excavate by the method, it is characterized in that step is as follows:

The line of demarcation of data determination excavation face upper-soft lower-hard ground is surveyed in a, base area, and is overlapping with line of demarcation, stratum or determining the line of demarcation of upper and lower step with upper/lower positions;

B, the construction of employing median septum of topping bar method, to top bar and be divided into top bar leading pilot tunnel and row pilot tunnel construction after topping bar, both drilling depths stagger 3 ~ 5m, top bar preliminary bracing, Temporary invert of topping bar are set respectively, top bar leading pilot tunnel and arrange median septum temporary lining between row pilot tunnel after topping bar, branch closes into ring;

C, employing remaining core soil in advance of getting out of a predicament or an embarrassing situation are constructed, delayed 0.5 ~ 1 times of tunnel excavation span of topping bar, and the Core Soil of getting out of a predicament or an embarrassing situation of reserved get out of a predicament or an embarrassing situation bottom inverted arch and centre excavates both sides of getting out of a predicament or an embarrassing situation and forms base tunnel, and applies both sides base tunnel preliminary bracing of getting out of a predicament or an embarrassing situation;

D, the delayed both sides base tunnel 2 ~ 3m that gets out of a predicament or an embarrassing situation, get out of a predicament or an embarrassing situation Core Soil and inverted arch that excavation is reserved, excavation drilling depth is less than or equal to 2m, applies inverted arch preliminary bracing of getting out of a predicament or an embarrassing situation with closed domain preliminary bracing;

E, getting out of a predicament or an embarrassing situation, geotextiles and EVA splash guard are arranged in inverted arch preliminary bracing surface, and build inverted arch two lining;

The median septum temporary lining and Temporary invert of topping bar of topping bar are removed in f, segmentation, are close to top bar preliminary bracing and both sides base tunnel preliminary bracing of getting out of a predicament or an embarrassing situation and build road surface two lining.

In step b, first excavation is topped bar leading pilot tunnel, then excavation top bar after row pilot tunnel;

The outer contour grouting small pilot pipe applying leading pilot tunnel of topping bar and the median septum grouting small pilot pipe arranged along median septum temporary lining, after in conduit, grouting soil intensity reaches design standard, excavate the leading pilot tunnel soil body of topping bar, immediately following applying top bar leading pilot tunnel preliminary bracing, median septum temporary lining and leading pilot tunnel Temporary invert of topping bar;

The setting and slip casting of outer contour grouting small pilot pipe of row pilot tunnel after topping bar, until grouting soil intensity reach top bar after design standard after row pilot drive, to apply after topping bar the preliminary bracing of row pilot tunnel and row pilot tunnel Temporary invert after topping bar.

Described arch springing place of topping bar and get out of a predicament or an embarrassing situation all arranges lock foot anchoring stock and slip casting.

In step f, disposable dismounting length is less than or equal to 8m.

The invention has the beneficial effects as follows: excavation method of the present invention is stronger to upper-soft lower-hard ground longspan tunnel excavation applicability, more traditional benching tunnelling method, effectively ensure that construction safety of topping bar, and comparatively intersecting median septum method (CRD), working procedure reduces, and realizes some mechanicalization construction, construction speed is accelerated, duration shortens, and have very big promotional value, social benefit is good.

Accompanying drawing explanation

Fig. 1 is working procedure cross-sectional drawing of the present invention.

Fig. 2 is working procedure plan view of the present invention.

Detailed description of the invention

As shown in Figure 1 and Figure 2, the present embodiment is a kind of longspan tunnel excavation method of soft lower hard compound stratum, and tunnel is divided into upper and lower step to excavate by the method, and concrete steps are as follows:

Data is surveyed in a, base area, determines the line of demarcation of excavation face upper-soft lower-hard ground, the excavation height of topping bar of selected economical rationality, and up/down steps line of demarcation should overlap with line of demarcation, stratum or below.

B, top bar and pass through soft soil layer, adopt the construction of median septum method; To top bar be divided into top bar leading pilot tunnel 1 and after topping bar row pilot tunnel 2 construct, both drilling depths stagger 3 ~ 5m, preliminary bracing of topping bar (comprising top bar leading pilot tunnel preliminary bracing 6 and row pilot tunnel preliminary bracing 7 after topping bar), Temporary invert of topping bar (comprising top bar leading pilot tunnel Temporary invert 11 and row pilot tunnel Temporary invert 12 after topping bar) are set respectively, top bar leading pilot tunnel 1 and arrange median septum temporary lining 10 between row pilot tunnel 2 after topping bar, branch closes into ring.This example all arranges lock foot anchoring stock 17 and slip casting at the arch springing place of topping bar.

First leading pilot tunnel 1 of topping bar is excavated in the present embodiment, excavate row pilot tunnel 2 after topping bar again: the outer contour grouting small pilot pipe 13 applying leading pilot tunnel 1 of topping bar and the median septum grouting small pilot pipe 14 arranged along median septum temporary lining 10, after in conduit, grouting soil intensity reaches design standard, excavate the soil body of leading pilot tunnel 1 of topping bar, immediately following applying top bar leading pilot tunnel preliminary bracing 6, median septum temporary lining 10 and leading pilot tunnel Temporary invert 11 of topping bar; The delayed leading pilot tunnel 3 ~ 5m that tops bar, excavate row pilot tunnel 2 after topping bar, the setting and slip casting of outer contour grouting small pilot pipe 13 of row pilot tunnel 2 after first topping bar, until grouting soil intensity reach top bar after design standard after row pilot tunnel 2 excavate, to apply after topping bar row pilot tunnel preliminary bracing 7 and row pilot tunnel Temporary invert 12 after topping bar.

C, employing remaining core soil in advance construction of getting out of a predicament or an embarrassing situation, delayed 0.5 ~ 1 times of tunnel excavation span of topping bar, reserved bottom inverted arch 5 and the middle Core Soil 4 of getting out of a predicament or an embarrassing situation of getting out of a predicament or an embarrassing situation, excavate both sides of getting out of a predicament or an embarrassing situation and form base tunnel 3, then apply both sides base tunnel preliminary bracing 8 of getting out of a predicament or an embarrassing situation, and lock foot anchoring stock 17 is all set at the arch springing place of getting out of a predicament or an embarrassing situation and slip casting.Base tunnel 3 soil excavation should reduce the disturbance to Core Soil 4 of getting out of a predicament or an embarrassing situation as far as possible, to keep its original supporting capacity.

D, delayed both sides base tunnel 3 the 2 ~ 3m that get out of a predicament or an embarrassing situation, get out of a predicament or an embarrassing situation Core Soil 4 and inverted arch 5 that excavation is reserved, strict control excavation drilling depth, is generally no more than 2m, applies inverted arch preliminary bracing 9 of getting out of a predicament or an embarrassing situation, close domain preliminary bracing; Control Core Soil 4 length of getting out of a predicament or an embarrassing situation is no more than 3m, is beneficial to mechanized construction of getting out of a predicament or an embarrassing situation.

E, getting out of a predicament or an embarrassing situation, geotextiles and EVA splash guard are arranged in inverted arch preliminary bracing 9 surface, and build inverted arch two and serve as a contrast 15;

The median septum temporary lining 10 and Temporary invert of topping bar of topping bar are removed in f, segmentation, are close to top bar preliminary bracing and both sides base tunnel preliminary bracing 8 of getting out of a predicament or an embarrassing situation and build road surface two and serve as a contrast 16.

Claims (4)

1. a longspan tunnel excavation method for upper soft lower hard compound stratum, tunnel is divided into upper and lower step to excavate by the method, it is characterized in that step is as follows:
The line of demarcation of data determination excavation face upper-soft lower-hard ground is surveyed in a, base area, and is overlapping with line of demarcation, stratum or determining the line of demarcation of upper and lower step with upper/lower positions;
B, the construction of employing median septum of topping bar method, to top bar and be divided into top bar leading pilot tunnel (1) and row pilot tunnel (2) construction after topping bar, both drilling depths stagger 3 ~ 5m, top bar preliminary bracing, Temporary invert of topping bar are set respectively, top bar leading pilot tunnel (1) and arrange median septum temporary lining (10) between row pilot tunnel (2) after topping bar, branch closes into ring;
C, employing remaining core soil in advance construction of getting out of a predicament or an embarrassing situation, delayed 0.5 ~ 1 times of tunnel excavation span of topping bar, the inverted arch (5) of reserved bottom of getting out of a predicament or an embarrassing situation and middle Core Soil of getting out of a predicament or an embarrassing situation (4), excavate both sides of getting out of a predicament or an embarrassing situation and form base tunnel (3), and apply both sides base tunnel preliminary bracing (8) of getting out of a predicament or an embarrassing situation;
D, delayed both sides base tunnel (3) 2 ~ 3m that gets out of a predicament or an embarrassing situation, Core Soil of getting out of a predicament or an embarrassing situation (4) inverted arch (5) that excavation is reserved, excavation drilling depth is less than or equal to 2m, applies inverted arch preliminary bracing (9) of getting out of a predicament or an embarrassing situation with closed domain preliminary bracing;
E, getting out of a predicament or an embarrassing situation, geotextiles and EVA splash guard are arranged in inverted arch preliminary bracing surface, and build inverted arch two and serve as a contrast (15);
The median septum temporary lining (10) and Temporary invert of topping bar of topping bar are removed in f, segmentation, are close to top bar preliminary bracing and both sides base tunnel preliminary bracing of getting out of a predicament or an embarrassing situation and build road surface two and serve as a contrast (16).
2. the longspan tunnel excavation method of soft lower hard compound stratum according to claim 1, is characterized in that: in step b, first excavation is topped bar leading pilot tunnel (1), then excavation top bar after row pilot tunnel (2);
The outer contour grouting small pilot pipe (13) applying leading pilot tunnel (1) of topping bar and the median septum grouting small pilot pipe (14) arranged along median septum temporary lining (10), after in conduit, grouting soil intensity reaches design standard, excavate leading pilot tunnel (1) soil body of topping bar, immediately following applying top bar leading pilot tunnel preliminary bracing (6), median septum temporary lining (10) and leading pilot tunnel Temporary invert (11) of topping bar;
The setting and slip casting of outer contour grouting small pilot pipe (13) of row pilot tunnel (2) after topping bar, until grouting soil intensity reach top bar after design standard after row pilot tunnel (2) excavation, to apply after topping bar row pilot tunnel preliminary bracing (7) and row pilot tunnel Temporary invert (12) after topping bar.
3. the longspan tunnel excavation method of soft lower hard compound stratum according to claim 1 and 2, is characterized in that: described in top bar, with the arch springing place of getting out of a predicament or an embarrassing situation, lock foot anchoring stock (17) be all set and slip casting.
4. the longspan tunnel excavation method of soft lower hard compound stratum according to claim 1 and 2, is characterized in that: in step f, disposable dismounting length is less than or equal to 8m.
CN201510228004.XA 2015-05-06 2015-05-06 The longspan tunnel excavation method of upper soft lower hard compound stratum CN104879131B (en)

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Cited By (12)

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Publication number Priority date Publication date Assignee Title
CN105240021A (en) * 2015-11-03 2016-01-13 甘肃路桥建设集团有限公司 CD-method construction method for improving loess tunnel with super-large cross section
CN105604576A (en) * 2016-01-20 2016-05-25 中铁隆工程集团有限公司 Soft rock stratum underground excavation large-section tunnel construction method and supporting system
CN106014424A (en) * 2016-06-27 2016-10-12 中交公局第三工程有限公司 Blasting excavation method for shallowly-overburdened and shallowly-buried bored tunnel
CN106121659A (en) * 2016-06-27 2016-11-16 中交公局第三工程有限公司 The narrow-bore tunnel excavation method of major urban arterial highway upper-soft lower-hard ground is worn under one
CN106837371A (en) * 2017-03-23 2017-06-13 中铁五局集团成都工程有限责任公司 The step band inverted arch construction method of large deformation tunnel two
CN107605490A (en) * 2017-08-28 2018-01-19 中交第二航务工程局有限公司 Single hole large cross-section tunnel double side wall construction conversion process
CN107905814A (en) * 2017-10-20 2018-04-13 长安大学 Large span loess tunnel top bar CD construction methods
CN108035733A (en) * 2017-11-01 2018-05-15 中铁四局集团有限公司 A kind of perpendicular support partial excavation method of rock matter large section tunnel steelframe dike combination
CN108131143A (en) * 2017-12-01 2018-06-08 长安大学 A kind of construction method of super-span tunnel top bar CD methods
CN108222947A (en) * 2017-12-26 2018-06-29 长安大学 A kind of construction method of two benching tunnelling method of super-span tunnel top bar CD normal direction conversion
CN108843332A (en) * 2018-07-15 2018-11-20 中铁二十局集团有限公司 Pass through fault belt large cross-section tunnel excavation and method for protecting support
CN109681212A (en) * 2018-12-17 2019-04-26 中交第二航务工程局有限公司 The excavation construction method of light section loess tunnel

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Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105240021A (en) * 2015-11-03 2016-01-13 甘肃路桥建设集团有限公司 CD-method construction method for improving loess tunnel with super-large cross section
CN105604576A (en) * 2016-01-20 2016-05-25 中铁隆工程集团有限公司 Soft rock stratum underground excavation large-section tunnel construction method and supporting system
CN105604576B (en) * 2016-01-20 2018-08-21 中铁隆工程集团有限公司 A kind of soft rock strata tunneling large-section tunnel construction method
CN106014424B (en) * 2016-06-27 2019-03-05 中交一公局第三工程有限公司 A kind of blasting digging method for shallow overlying strata shallow-depth-excavation tunnel
CN106014424A (en) * 2016-06-27 2016-10-12 中交公局第三工程有限公司 Blasting excavation method for shallowly-overburdened and shallowly-buried bored tunnel
CN106121659A (en) * 2016-06-27 2016-11-16 中交公局第三工程有限公司 The narrow-bore tunnel excavation method of major urban arterial highway upper-soft lower-hard ground is worn under one
CN106837371A (en) * 2017-03-23 2017-06-13 中铁五局集团成都工程有限责任公司 The step band inverted arch construction method of large deformation tunnel two
CN107605490A (en) * 2017-08-28 2018-01-19 中交第二航务工程局有限公司 Single hole large cross-section tunnel double side wall construction conversion process
CN107605490B (en) * 2017-08-28 2018-11-09 中交第二航务工程局有限公司 Single hole large cross-section tunnel double side wall construction conversion process
CN107905814A (en) * 2017-10-20 2018-04-13 长安大学 Large span loess tunnel top bar CD construction methods
CN107905814B (en) * 2017-10-20 2019-08-13 长安大学 Large span loess tunnel top bar CD construction method
CN108035733A (en) * 2017-11-01 2018-05-15 中铁四局集团有限公司 A kind of perpendicular support partial excavation method of rock matter large section tunnel steelframe dike combination
CN108035733B (en) * 2017-11-01 2019-10-25 中铁四局集团有限公司 A kind of perpendicular support partial excavation method of rock matter large section tunnel steelframe dike combination
CN108131143A (en) * 2017-12-01 2018-06-08 长安大学 A kind of construction method of super-span tunnel top bar CD methods
CN108222947B (en) * 2017-12-26 2019-05-21 长安大学 A kind of construction method of two benching tunnelling method of super-span tunnel top bar CD normal direction conversion
CN108222947A (en) * 2017-12-26 2018-06-29 长安大学 A kind of construction method of two benching tunnelling method of super-span tunnel top bar CD normal direction conversion
CN108843332A (en) * 2018-07-15 2018-11-20 中铁二十局集团有限公司 Pass through fault belt large cross-section tunnel excavation and method for protecting support
CN109681212A (en) * 2018-12-17 2019-04-26 中交第二航务工程局有限公司 The excavation construction method of light section loess tunnel

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