CN112727512A - Advanced detection, shock insulation and advanced transverse counter-pulling anchor rod system of ultra-small clear distance tunnel - Google Patents
Advanced detection, shock insulation and advanced transverse counter-pulling anchor rod system of ultra-small clear distance tunnel Download PDFInfo
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- CN112727512A CN112727512A CN202011638076.9A CN202011638076A CN112727512A CN 112727512 A CN112727512 A CN 112727512A CN 202011638076 A CN202011638076 A CN 202011638076A CN 112727512 A CN112727512 A CN 112727512A
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- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D20/00—Setting anchoring-bolts
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- 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
- E21B7/04—Directional drilling
- E21B7/046—Directional drilling horizontal drilling
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- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D21/00—Anchoring-bolts for roof, floor in galleries or longwall working, or shaft-lining protection
- E21D21/008—Anchoring or tensioning means
Abstract
The invention relates to an advanced detection, shock insulation and advanced transverse counter-pulling anchor rod system for an ultra-small clear distance tunnel, which is used for excavating the ultra-small clear distance tunnel and comprises an advanced detection unit: after the tunnel pilot tunnel is excavated, a pilot horizontal drilling hole is longitudinally drilled in the tunnel backward tunnel along the side wall profile of the tunnel backward tunnel, and an in-hole television probe is used for identifying the surrounding rock damage condition through the pilot horizontal drilling hole; shock insulation and leading horizontal counter-pulling anchor rod unit: the method comprises the steps of drilling a leading horizontal drilling hole from a tunnel leading hole to a tunnel trailing hole, drilling a transverse anchor rod hole which forms a cross hole with the leading horizontal drilling hole, and driving an anchor rod and a pre-tensioning anchor head from the tunnel leading hole, opening the pre-tensioning anchor head at the cross hole, and applying prestress to form a counter-tension anchor rod. Compared with other methods, the method has the advantages of simple construction, low cost, strong applicability, no limitation of terrain conditions and overall line types, and great significance for tunnel engineering.
Description
Technical Field
The invention belongs to the fields of geological engineering, geotechnical engineering, tunnels and underground constructional engineering, relates to a split anchor rod system, and particularly relates to an advanced detection, shock insulation and advanced transverse split anchor rod system for an ultra-small clear distance tunnel, and a use method and application thereof.
Background
The small clear distance tunnel is a special tunnel structure form in which the thickness of a middle wall rock (middle sandwich rock) column between tunnels is smaller than a tunnel specification suggested value, and the general clear distance of the small clear distance tunnel is preferably larger than 6.0-8.0 m according to experience of a large number of built small clear distance tunnels and related domestic scientific research results. And the ultra-small clear distance tunnel (the clear distance is less than or equal to 6.0m) is a special tunnel structure form with the clear distance smaller than the common space adopted by the common small clear distance tunnel.
In the construction of roads in mountain areas with complex geological conditions, the ultra-small clear distance tunnel has the advantages of simple construction, short construction period, low manufacturing cost and the like, and is widely applied. However, because the center distance between the two caverns is small, the stress fields have spatial mutual influence in the excavation process between the double tunnels of the ultra-small clear distance tunnel, which is extremely unfavorable for the construction safety of tunnel engineering. And the stability and the bearing capacity of the rock layer in the tunnel are unstable, and the tunnel with weak surrounding rock strength of the middle-sandwiched rock is difficult to be self-stabilized without protection.
Disclosure of Invention
The invention aims to provide an advanced detection, shock insulation and advanced transverse counter-pulling anchor rod system of an ultra-small clear distance tunnel and a using method and application thereof. Compared with other methods, the method has the advantages of simple construction, low cost and strong applicability, is not limited by terrain conditions and general line types, and has great significance for tunnel engineering.
The purpose of the invention can be realized by the following technical scheme:
the invention provides an advanced detection, shock insulation and advanced transverse counter-pulling anchor rod system for an ultra-small clear-distance tunnel, which is used for excavating the ultra-small clear-distance tunnel and comprises an advanced detection unit and a shock insulation and advanced transverse counter-pulling anchor rod unit;
the advanced detection unit comprises:
drilling horizontally in advance, after excavating the tunnel pilot tunnel, drilling a tunnel backward tunnel along the profile of the side wall of the tunnel, and using the tunnel backward tunnel as a shock insulation pressure relief hole,
the in-hole television probe is used for identifying the damage condition of the surrounding rock through advanced horizontal drilling;
the shock insulation and advanced transverse counter-pulling anchor rod unit is provided with:
a transverse anchor rod drilling hole, a leading horizontal drilling hole which is drilled from a tunnel leading hole to a tunnel trailing hole and forms a cross hole with the leading horizontal drilling hole,
the opposite-pulling anchor rod consists of anchor rod and pre-tensioning anchor head, and is formed by lowering the anchor rod and the pre-tensioning anchor head from the tunnel via the pilot hole, opening the pre-tensioning anchor head at the cross hole and applying prestress.
Preferably, the advanced horizontal bores are arranged in a plurality of rows in the height direction.
Further preferably, the advanced horizontal bores are provided in three rows in the height direction.
Preferably, the advanced horizontal drilling hole is a large-caliber horizontal hole with an inner diameter range of 100 and 200 mm.
Preferably, the transverse anchor hole is matched with the size of the anchor.
Preferably, the pre-tensioning anchor head is an anchor head of a counter-tension anchor rod applying pre-stress by a post-tensioning method.
Preferably, the clear distance of the ultra-small clear distance tunnel is less than or equal to 6.0 m.
The invention provides a use method of an advanced detection, shock insulation and advanced transverse counter-pulling anchor rod system of an ultra-small clear distance tunnel, which comprises the following steps:
s1: after the excavation of the advanced tunnel of the tunnel is finished, drilling advanced horizontal drill holes in advance according to the profile on the side wall of the rock-sandwiched backward tunnel in the ultra-small clear distance tunnel;
s2: identifying the damage condition of the surrounding rock by drilling a horizontal hole in advance and a television probe in the hole;
s3: drilling a transverse anchor rod drilling hole from the advanced horizontal drilling hole of the tunnel to the advanced horizontal drilling hole of the tunnel backward hole to form a cross hole;
s4: and (3) putting the anchor rod and the pre-tensioning anchor head into the tunnel pilot tunnel, opening the pre-tensioning anchor head at the cross hole, and applying prestress to form a counter-pulling anchor rod so as to protect the rock clamped in the ultra-small clear distance tunnel.
Preferably, in step S1, a pilot horizontal bore is drilled with a drill.
The third aspect of the invention provides application of the advanced detection, shock insulation and advanced transverse opposite pulling anchor rod system of the ultra-small clear distance tunnel, which is used for excavating the ultra-small clear distance tunnel and protecting rock clamping in the ultra-small clear distance tunnel.
The television probe in the hole of the advanced detection unit can identify the damage condition of the surrounding rock by drilling the advanced horizontal drilling hole, so as to fulfill the aim of advanced detection; the advanced horizontal drilling hole is simultaneously used as a shock insulation pressure relief hole. The shock insulation pressure relief holes (advanced horizontal drilling holes) can form a weakening area in the surrounding rock, stress is released, meanwhile, surrounding stress of the surrounding rock is transferred to deep stable surrounding rock, the stress environment of the tunnel is improved, an effective compensation space is provided for expansion deformation of the surrounding rock, and the purpose of reducing deformation of the tunnel is achieved. The side wall opposite-pulling anchor rod can effectively reduce the influence on the backward tunnel during the excavation of the forward tunnel, improve the integrity of the soil body, strengthen the lateral constraint and enable the soil body to tend to be stable.
Compared with the prior art, the method is used for the construction process of the ultra-small clear distance tunnel in the tunnel engineering, has the advantages of simple construction, short construction period, low manufacturing cost and strong applicability compared with other methods, and has great significance for the tunnel engineering.
Drawings
Fig. 1 is a schematic view of a split bolt system of the present invention (only one row of advanced horizontal boreholes is shown).
Fig. 2 is a schematic connection diagram of seismic isolation and advanced transverse counter-pulling anchor rod units in three rows of advanced horizontal drilling in embodiment 1 of the invention.
Fig. 3 is a schematic view of a pretensioning anchor head of a counter-pulling anchor rod in a cross hole according to embodiment 1 of the invention.
In the figure, I is a tunnel advance hole, II is a tunnel backward hole, 1 is an in-hole television probe, 2 is an advance horizontal drilling hole, 3 is a counter-pull anchor rod, 31 is a pre-tensioning anchor head, and 4 is a transverse anchor rod drilling hole.
Detailed Description
The invention is described in detail below with reference to the figures and specific embodiments.
Example 1
An advanced detection, shock insulation and advanced transverse counter-pulling anchor rod system of an ultra-small clear distance tunnel is shown in figures 1-3 and is used for excavating the ultra-small clear distance tunnel and comprises an advanced detection unit and a shock insulation and advanced transverse counter-pulling anchor rod unit;
the advanced detection unit has an advanced horizontal borehole 2 and an in-hole television probe, wherein: after the advanced horizontal drilling hole 2 is excavated in the tunnel advance hole I, a tunnel backward hole II is longitudinally drilled along the side wall profile of the advanced horizontal drilling hole and is used as a shock insulation pressure relief hole, and the in-hole television probe 1 is used for identifying the damage condition of surrounding rocks through the advanced horizontal drilling hole 2;
shock insulation has horizontal stock drilling 4 and counter-pull stock 3 with leading horizontal counter-pull stock unit, wherein: the transverse anchor rod drilling hole 4 is drilled from the tunnel advance hole I to the advance horizontal drilling hole 2 of the tunnel backward hole II, and forms a cross hole with the advance horizontal drilling hole 2, the opposite-pulling anchor rod 3 is composed of an anchor rod and a pre-tensioning anchor head 31, the anchor rod and the pre-tensioning anchor head 31 are put into the tunnel advance hole I, the pre-tensioning anchor head 31 is opened at the cross hole, and prestress is applied to form the transverse anchor rod drilling hole.
The ultra-small clear distance tunnel in the embodiment means that the clear distance is less than or equal to 6.0 m.
The advanced horizontal bores 2 may be provided in a plurality of rows in the height direction. In the present embodiment, it is preferable that the advanced horizontal bores 2 are provided in three rows in the height direction. In this embodiment, the advanced horizontal drilling hole (2) is a large-diameter horizontal hole with an inner diameter of 100 and 200 mm. The transverse anchor bore 4 is preferably matched to the size of the anchor. The pre-tensioning anchor head 31 is preferably the anchor head of a counter-tensioning anchor rod which is prestressed by post-tensioning, but other forms of pre-tensioning anchor heads may be used.
The in-hole television probe of the advanced detection unit can identify the damage condition of the surrounding rock by drilling into an advanced horizontal drilling hole, so as to fulfill the aim of advanced detection; the advanced horizontal drilling hole is simultaneously used as a shock insulation pressure relief hole. The shock insulation pressure relief holes (advanced horizontal drilling holes) can form a weakening area in the surrounding rock, stress is released, meanwhile, surrounding stress of the surrounding rock is transferred to deep stable surrounding rock, the stress environment of the tunnel is improved, an effective compensation space is provided for expansion deformation of the surrounding rock, and the purpose of reducing deformation of the tunnel is achieved. The side wall opposite-pulling anchor rod can effectively reduce the influence on the backward tunnel during the excavation of the forward tunnel, improve the integrity of the soil body, strengthen the lateral constraint and enable the soil body to tend to be stable.
The application method of the advanced detection, shock insulation and advanced transverse counter-pulling anchor rod system of the ultra-small clear distance tunnel is characterized by comprising the following steps of:
s1: after the excavation of the tunnel pilot tunnel I is finished, drilling a pilot horizontal drilling hole 2 in advance by using a drilling machine according to the outline on the side wall of a tunnel pilot tunnel II which clamps rocks in the ultra-small clear distance tunnel;
s2: identifying the damage condition of the surrounding rock by drilling a television probe 1 into the hole through an advanced horizontal drilling hole 2;
s3: drilling a transverse anchor rod drilling hole 4 from the tunnel advance hole I to the advance horizontal drilling hole 2 of the tunnel backward hole II to form a cross hole;
s4: and (3) an anchor rod and a pre-tensioning anchor head 31 are put into the tunnel pilot tunnel 2, the pre-tensioning anchor head 31 is opened at the cross hole, and prestress is applied to form a counter-pulling anchor rod 3, so that the rock clamped in the ultra-small clear distance tunnel is protected.
The split anchor rod system can be used for excavating the ultra-small clear distance tunnel to protect the rock clamped in the ultra-small clear distance tunnel.
The embodiments described above are intended to facilitate the understanding and use of the invention by those skilled in the art. It will be readily apparent to those skilled in the art that various modifications to these embodiments may be made, and the generic principles described herein may be applied to other embodiments without the use of the inventive faculty. Therefore, the present invention is not limited to the above embodiments, and those skilled in the art should make improvements and modifications within the scope of the present invention based on the disclosure of the present invention.
Claims (10)
1. An advanced detection, shock insulation and advanced transverse counter-pulling anchor rod system for an ultra-small clear distance tunnel is used for excavating the ultra-small clear distance tunnel and is characterized by comprising an advanced detection unit and a shock insulation and advanced transverse counter-pulling anchor rod unit;
the advanced detection unit comprises:
a leading horizontal drilling hole (2) is drilled longitudinally along the profile of the side wall of a tunnel backward tunnel (II) after a tunnel forward tunnel (I) is excavated and is used as a shock insulation pressure relief hole,
the in-hole television probe (1) is used for identifying the damage condition of the surrounding rock through the advanced horizontal drilling (2);
the shock insulation and advanced transverse counter-pulling anchor rod unit is provided with:
a transverse anchor rod drilling hole (4) which is drilled from the tunnel advancing hole (I) to the advanced horizontal drilling hole (2) of the tunnel backward hole (II) and forms a cross hole with the advanced horizontal drilling hole (2),
the counter-pulling anchor rod (3) consists of an anchor rod and a pre-tensioning anchor head (31), the anchor rod and the pre-tensioning anchor head (31) are put into the tunnel from the pilot hole (I), the pre-tensioning anchor head (31) is opened at the cross hole, and prestress is applied to form the counter-pulling anchor rod.
2. Advanced detection, seismic isolation and advanced transverse counter-pulling anchor rod system for ultra-small clear distance tunnels according to claim 1, characterized in that the advanced horizontal boreholes (2) are provided with a plurality of rows in the height direction.
3. Advanced detection, seismic isolation and advanced transverse counter-pulling anchor rod system for ultra-small clear distance tunnels according to claim 2, characterized in that the advanced horizontal boreholes (2) are provided with three rows in the height direction.
4. The advanced detection, vibration isolation and advanced transverse opposite-pulling anchor rod system for the ultra-small clear distance tunnel according to claim 1, wherein the advanced horizontal drilling hole (2) is a large-caliber horizontal hole with an inner diameter of 100-200 mm.
5. Advanced detection, seismic isolation and advanced transverse counter-pull anchor rod system for ultra-small clear distance tunnels according to claim 1, characterized in that the transverse anchor rod drilling holes (4) are matched with the size of the anchor rods.
6. Advanced detection, seismic isolation and advanced transverse counter-pulling anchor rod system of ultra-small clearance tunnels according to claim 1, characterized in that the pre-tensioning anchor head (31) applies the pre-stressed anchor head of the counter-pulling anchor rod by post-tensioning method.
7. The advanced detection, seismic isolation and advanced transverse opposite pulling anchor rod system of the ultra-small clear distance tunnel according to claim 1, wherein the clear distance of the ultra-small clear distance tunnel is less than or equal to 6.0 m.
8. The use method of the advanced detection, vibration isolation and advanced transverse opposite-pulling anchor rod system of the ultra-small clear distance tunnel according to claim 1 is characterized by comprising the following steps:
s1: after the excavation of the tunnel pilot tunnel (I) is finished, drilling a pilot horizontal drilling hole (2) in advance according to the outline on the side wall of a tunnel backward tunnel (II) which clamps rocks in the ultra-small clear distance tunnel;
s2: identifying the damage condition of the surrounding rock by a TV probe (1) which drills into the hole through an advanced horizontal drilling hole (2);
s3: drilling a transverse anchor rod drilling hole (4) from the tunnel advance hole (I) to the advance horizontal drilling hole (2) of the tunnel backward hole (II) to form a cross hole;
s4: and (3) an anchor rod and a pre-tensioning anchor head (31) are put into the tunnel pilot tunnel (2), the pre-tensioning anchor head (31) is opened at the cross hole, and prestress is applied to form a counter-pulling anchor rod (3) so as to protect the rock clamped in the ultra-small clear distance tunnel.
9. The method for using the advanced detection, vibration isolation and advanced transverse opposite-pulling anchor rod system of the ultra-small clear distance tunnel according to claim 8, wherein in the step S1, an advanced horizontal drilling hole (2) is drilled by a drilling machine.
10. The application of the advanced detection, vibration isolation and advanced transverse opposite pulling anchor rod system of the ultra-small clear distance tunnel according to claim 1 is characterized in that the system is used for excavating the ultra-small clear distance tunnel to protect the rock clamped in the ultra-small clear distance tunnel.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202011638076.9A CN112727512B (en) | 2020-12-31 | 2020-12-31 | Advanced detection, shock insulation and advanced transverse counter-pulling anchor rod system of ultra-small clear distance tunnel |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202011638076.9A CN112727512B (en) | 2020-12-31 | 2020-12-31 | Advanced detection, shock insulation and advanced transverse counter-pulling anchor rod system of ultra-small clear distance tunnel |
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| CN112727512A true CN112727512A (en) | 2021-04-30 |
| CN112727512B CN112727512B (en) | 2022-09-16 |
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2020
- 2020-12-31 CN CN202011638076.9A patent/CN112727512B/en active Active
Patent Citations (5)
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| CN102966360A (en) * | 2012-11-26 | 2013-03-13 | 中铁四局集团第二工程有限公司 | Method for reinforcing rock walls in neighborhood tunnel |
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