A kind of front pre-grouting method of high-pressure water-enriched weak surrounding rock mountain tunnel
Technical field
The present invention relates to a kind of front pre-grouting method in tunnel, specially a kind of high-pressure water-enriched weak surrounding rock mountain tunnel
Front pre-grouting method, belong to Application in Building technical field.
Background technology
Tunnel is construction project key project, and some constructing tunnel areas need to pass through water-rich fault zone, fracture belt position rock
Body crushes, developmental joint fissure, and tax water condition is preferable, and edpth of tunnel is big, and water pressure is high, because fracture location rock mass is relatively more broken
Broken, construction period easily caves in and gushing water, the construction disaster such as mud of dashing forward.The Treatment Methods of Tunnel Gushing are based on " row " at present,
Current most of tunnel uses the scheme based on row to big flow water process measure, the tunnel built based on " row ", though
So solve the problem in many tunnels, but also leave hidden danger in some tunnels:Make tunnel that it is big to have drawn surrounding into drain cavern
The underground water of amount, thus the loss of underground water is caused, a series of problem is generated, such as influences liner structure and traffic safety,
Engineering area water-bearing layer is caused in terms of environment to make deterioration of the ecological environment etc. by drainage.
There is prominent water burst situation when building, during active fault in some current tunnels, when water yield is high, are handling
After Tunnel Gushing, take which kind of measure to reinforce front of tunnel heading weak surrounding rock and ensure that tunnel safety construction is critical problem, it is right
High hydraulic pressure, the weak surrounding rock of big yield advanced pre-reinforcement carried out using tunneling boring curtain-grouting, it is necessary to grouting pressure it is big, slip casting
When be likely to occur slip casting blind area, reduce slip casting effect.
The content of the invention
It is an object of the invention to provide a kind of front pre-grouting method of high-pressure water-enriched weak surrounding rock mountain tunnel, pass through
Blocked up in row, the hydraulic pressure of front of tunnel heading country rock is reduced by lower section osculum, to reach more preferable slip casting effect.
To achieve the above object, a kind of front pre-grouting method of high-pressure water-enriched weak surrounding rock mountain tunnel, including tunnel,
The inside in the tunnel is provided with face, and pours wall for grouting in the side wall of the face;The face be provided with upper section,
Lower section, the upper section is provided with injected hole of upper stage and carries out tunneling boring curtain-grouting, and the lower section is provided with osculum
Reduce front of tunnel heading country rock hydraulic pressure;The side wall of the face is provided with sealing batholite;Slip casting is poured in the one end in the tunnel
Curtain reinforcement area, the inside in the tunnel is provided with pre-grouting area, and the one end in the pre-grouting area is provided with next stage slip casting
Area;
Its step is as follows:
Step 1:Advance geologic prediction is carried out, detects the front of tunnel heading fault belt, underground water position;
Step 2:Apart from water-rich fault zone one end apart from when, stop excavation construction, pour the wall for grouting, it is described only
Wall thickness empirically value is starched, it is relevant with the curtain-grouting back-up coat thickness;
Step 3:After pouring the wall for grouting, advance boreholes are carried out, according to drilling water yield actual measurement hydraulic pressure, in water
Lower drain water slip casting is blocked up in the case that pressure is very high, in selection;
Step 4:In the lower section borehole of the face, the osculum is set, the draining hole number according to
Survey water to set, the underground water of discharge is drained by tunnel cavern drainage groove;
Step 5:In strict accordance with front pre-grouting design the face it is described on section lay it is described on rank
Section injected hole, using protrusive segmenting slip casting, grouting sequence:" inner ring behind first outer ring, with collar aperture interval jump hole ";
Step 6:After the completion of the pre-grouting layer, with reference to advanced tubal curtain pre-reinforcement measure, implement to excavate, according to country rock
Characteristic selects benching tunnelling method or full-face excavation, excavates to reserved paragraph as the described of the pre-grouting layer of next stage
Sealing batholite, start next stage advanced curtain-grouting.
Preferably, in order to reduce the front of tunnel heading country rock hydraulic pressure.The osculum equidistantly divides on the lower section
Cloth.
Preferably, in order to reinforce the front of tunnel heading country rock, the pre-grouting area is located at the front of the face.
The beneficial effects of the invention are as follows:Of the invention this is reinforced before face using the method for upper stifled lower drain water slip casting
Square country rock, injected hole is set to carry out tunneling boring curtain-grouting in upper section, but because hydraulic pressure is high in high-pressure water-enriched country rock, only
Grouting pressure is improved, may result in that slip casting effect is poor, slip casting blind area occurs, therefore in lower section setting osculum, passes through row
Water hole reduces front of tunnel heading country rock hydraulic pressure, is blocked up in row, slip casting is uniform, closely knit to reach, and reinforces the effect of weak surrounding rock.This
Invention is solved in high-pressure water-enriched country rock the problem of hydraulic pressure is high, grouting difficulty, is advantageous to using upper stifled lower drain water grouting method
Reduce mortar depositing construction cost.
Brief description of the drawings
Fig. 1 is upper stifled lower drain water slip casting vertical section schematic diagram;
Fig. 2 is upper stifled lower drain water slip casting schematic cross-sectional view.
In figure:1st, osculum, 2, lower section, 3, face, 4, sealing batholite, 5, wall for grouting, 6, upper section, 7, the upper stage
Injected hole, 8, tunnel, 9, pre-grouting area, 10, grouting curtain stabilization zone, 11, next stage slip casting area.
Embodiment
Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is carried out clear, complete
Site preparation describes, it is clear that described embodiment is only part of the embodiment of the present invention, rather than whole embodiments.It is based on
Embodiment in the present invention, those of ordinary skill in the art are obtained every other under the premise of creative work is not made
Embodiment, belong to the scope of protection of the invention.
Refer to shown in Fig. 1-2, a kind of front pre-grouting method of high-pressure water-enriched weak surrounding rock mountain tunnel, including tunnel
8, the inside in the tunnel 8 is provided with face 3, and wall for grouting 5 is poured in the side wall of the face 3;The face 3 is provided with
Upper section 6, lower section 2, the upper section 6 are provided with injected hole of upper stage 7 and carry out tunneling boring curtain-grouting, and the lower section 2
The front country rock hydraulic pressure of face 3 is reduced provided with osculum 1;The side wall of the face 3 is provided with sealing batholite 4;The tunnel
Grouting curtain stabilization zone 10 is poured in the one end in road 8, and the inside in the tunnel 8 is provided with pre-grouting area 9, and the pre-grouting area
9 one end is provided with next stage slip casting area 11;
Step is as follows:
Step 1:Advance geologic prediction is carried out, detects the front fault belt of face 3, underground water position;
Step 2:Apart from water-rich fault zone one end apart from when, stop excavation construction, pour the wall for grouting 5, it is described only
The thickness of wall 5 empirically value is starched, it is relevant with the thickness of curtain-grouting back-up coat 10;
Step 3:After pouring the wall for grouting 5, advance boreholes are carried out, according to drilling water yield actual measurement hydraulic pressure, in water
Lower drain water slip casting is blocked up in the case that pressure is very high, in selection;
Step 4:In the lower drilling of section 2 of the face 3, the osculum 1, the quantity of osculum 1 are set
Set according to actual measurement water, the underground water of discharge is drained by tunnel cavern drainage groove;
Step 5:In strict accordance with front pre-grouting design the face 3 it is described on section 6 lay on described
Stage injected hole 7, using protrusive segmenting slip casting, grouting sequence:" inner ring behind first outer ring, with collar aperture interval jump hole ";
Step 6:After the completion of the pre-grouting layer 9, with reference to advanced tubal curtain pre-reinforcement measure, implement to excavate, according to country rock
Characteristic selects benching tunnelling method or full-face excavation, excavates to reserved institute of the paragraph as the pre-grouting layer 9 of next stage
Sealing batholite 4 is stated, starts next stage advanced curtain-grouting.
As a kind of technical optimization scheme of the present invention, the osculum 1 is equally spaced on the lower section 2.
As a kind of technical optimization scheme of the present invention, the pre-grouting area 9 is located at the front of the face 3.
In the use of the present invention, advance geologic prediction is first carried out, detection face 3 front fault belt, level of ground water
Put;Apart from water-rich fault zone one end apart from when, stop excavation construction, pour wall for grouting 5, the thickness of wall for grouting 5 empirically value,
It is relevant with the thickness of curtain-grouting back-up coat 10.After pouring wall for grouting 5, advance boreholes are carried out, according to drilling water yield actual measurement
Hydraulic pressure, lower drain water slip casting is blocked up in the case where hydraulic pressure is very high, in selection.Draining is set in the drilling of lower section 2 of face 3 again
Hole 1, the quantity of osculum 1 are set according to actual measurement water, and the underground water of discharge is drained by tunnel cavern drainage groove.
In work progress, the slip casting of upper stage is laid in strict accordance with upper section 6 of the front pre-grouting design in face 3
Hole 7, using protrusive segmenting slip casting, grouting sequence:" inner ring behind first outer ring, with collar aperture interval jump hole ".Pre-grouting layer 9 is completed
Afterwards, with reference to advanced tubal curtain pre-reinforcement measure, implement to excavate, benching tunnelling method or full-face excavation are selected according to characteristics of surrounding rock, opened
Sealing batholite 4 of the reserved paragraph as the pre-grouting layer 9 of next stage is dug, starts next stage advanced curtain-grouting.
It is obvious to a person skilled in the art that the invention is not restricted to the details of above-mentioned one exemplary embodiment, Er Qie
In the case of without departing substantially from spirit or essential attributes of the invention, the present invention can be realized in other specific forms.Therefore, no matter
From the point of view of which point, embodiment all should be regarded as exemplary, and be nonrestrictive, the scope of the present invention is by appended power
Profit requires rather than described above limits, it is intended that all in the implication and scope of the equivalency of claim by falling
Change is included in the present invention.Any reference in claim should not be considered as to the involved claim of limitation.
Moreover, it will be appreciated that although the present specification is described in terms of embodiments, not each embodiment is only wrapped
Containing an independent technical scheme, this narrating mode of specification is only that those skilled in the art should for clarity
Using specification as an entirety, the technical solutions in the various embodiments may also be suitably combined, forms those skilled in the art
It is appreciated that other embodiment.