CN103939112A

CN103939112A - Down-cross cheuch tunnel double-layer forepoling structure

Info

Publication number: CN103939112A
Application number: CN201410189986.1A
Authority: CN
Inventors: 张剑
Original assignee: 中铁第一勘察设计院集团有限公司
Priority date: 2014-05-07
Filing date: 2014-05-07
Publication date: 2014-07-23

Abstract

The invention relates to a down-cross cheuch tunnel double-layer forepoling structure. The top of a down-cross cheuch tunnel is not buried deep, the stratum stability is poor, collapse and roof falling can be caused easily, and surface water is reversely poured into the tunnel. A plurality of annular steel frames are arranged on the inner wall of the tunnel in the longitudinal direction and coated with sprayed concrete so that the steel frames can be covered with the sprayed concrete; multi-ring self-propelling pipe sheds are arranged in the surrounding rock on the arched portion of the tunnel in the longitudinal direction in a hit mode, a small guide pipe is arranged between every two transversely adjacent self-propelling pipe sheds in a hit mode, and four small guide pipes are arranged between every two longitudinally adjacent self-propelling pipe sheds in a hit mode; solidifying grout is injected into the small guide pipes in a pressed mode, and the grout is combined with the rock mass on the upper portion of the arched portion to form the solidified rock mass with the injected grout; the extrapolation angle of each small guide pipe is larger than the extrapolation angle of each self-propelling pipe shed. The advantages of the long pipe sheds and the advantages of the short pipe sheds are fully combined, the rock mass is solidified through pre-grouting, the self-bearing capacity of the stratum is fully utilized, and therefore an economical, reasonable, safe and reliable protecting shell can be formed, and construction of the tunnel is safe.

Description

Under wear the double-deck advance support structure in cheuch tunnel

Technical field

the invention belongs to tunnel traffic field of engineering technology, be specifically related to wear under one the double-deck advance support structure in cheuch tunnel.

Background technology

The traffic engineering such as mountain railway, highway need to be built a large amount of construction of tunnel, to improve line standard and to improve operation condition, grow on the earth's surface, mountain range that tunnel passes often gully, many cheuches also have long-term flowing water, when construction of tunnel is passed through below cheuch, the main problem existing is: tunnel top buried depth is smaller, mostly is alluvial deposit in ditch, subterrane is also weathered layer, and formation stability is poor; Stratum self-stable ability is low, the time is short, and construction needs quick supporting sealing, is often difficult to accomplish.Slightly improper, be easy to collapse and cave-in, surface water pours in down a chimney into tunnel, construction safety is caused to significant damage, build up rear tunnel structure and also have the disease hidden danger such as cracking, percolating water, therefore, select rational advance support measure, make full use of self, reduce to greatest extent disturbance, most important to the construction of safety cheuch section.

Summary of the invention

The object of this invention is to provide under one and wear the double-deck advance support structure in cheuch tunnel, effectively prevent collapse and cave-in and surface water to pour in down a chimney into tunnel.

The technical solution adopted in the present invention is:

Under wear the double-deck advance support structure in cheuch tunnel, it is characterized in that:

The steelframe of multiple tracks hoop is longitudinally set in tunnel inner wall, and sprays sprayed mortar covering steelframe;

In the country rock of arch, tunnel, longitudinally set many ring self-advancing type pipe canopies, laterally between adjacent self-advancing type pipe canopy, set a ductule, longitudinally between adjacent self-advancing type pipe canopy, set four ductules; The fixed slurries of pressure injection in ductule, are combined with top, arch rock mass and form grouting reinforcement rock mass.

The extrapolation angle of ductule is greater than the extrapolation angle of self-advancing type pipe canopy.

The present invention has the following advantages:

The present invention has fully studied topographic and geologic condition and the difficulty of construction of time wearing cheuch section; by abundant the advantage of long pipe shed and tubulature combination; and by pre-grouting reinforcement rock mass; take full advantage of rock stratum self-supporting ability; thereby form a kind of economical rationality, safe and reliable containment vessel, make constructing tunnel in a safe condition.

Brief description of the drawings

Fig. 1 is front of the present invention arrangement diagram.

Fig. 2 is longitudinal surface arrangement diagram of the present invention.

In figure, 1-grouting reinforcement rock mass, 2-sprayed mortar, 3-steelframe, 4-self-advancing type pipe canopy, 5-ductule.

Detailed description of the invention

Below in conjunction with detailed description of the invention, the present invention will be described in detail.

The present invention relates to wear under one the double-deck advance support structure in cheuch tunnel, the steelframe 3 of multiple tracks hoop is longitudinally set in tunnel inner wall, and spray sprayed mortar 2 and cover steelframe 3, form one deck protection.In the country rock of arch, tunnel, longitudinally set many ring self-advancing type pipe canopies 4, self-advancing type pipe canopy 4 is for carrying drill bit device, directly punching is installed, and laterally between adjacent self-advancing type pipe canopy 4, sets a ductule 5, longitudinally between adjacent self-advancing type pipe canopy 4, sets four ductules 5; At the fixed slurries of the interior pressure injection of ductule 5, be combined with top, arch rock mass and form grouting reinforcement rock mass 1, form another layer of protection; finally complete double-deck supporting measure; form safeguard protection shell in arch, can effectively control arch, tunnel and cave in, guarantee construction and structural safety.The extrapolation angle (10～15 °) of ductule 5 is greater than the extrapolation angle (3～5 °) of self-advancing type pipe canopy 4.Tunnel excavation should carry out under the protection of a upper ring, and self-advancing type pipe canopy 4 longitudinally all should suitably overlap overlapping certain limit with ductule 5.

It is cited that content of the present invention is not limited to embodiment, and the conversion of any equivalence that those of ordinary skill in the art take technical solution of the present invention by reading manual of the present invention, is claim of the present invention and contains.

Claims

1. wear down the double-deck advance support structure in cheuch tunnel, it is characterized in that:

The steelframe (3) of multiple tracks hoop is longitudinally set in tunnel inner wall, and sprays sprayed mortar (2) covering steelframe (3);

In the country rock of arch, tunnel, longitudinally set many ring self-advancing type pipe canopies (4), laterally between adjacent self-advancing type pipe canopy (4), set a ductule (5), longitudinally between adjacent self-advancing type pipe canopy (4), set four ductules (5); The fixed slurries of pressure injection in ductule (5), are combined with top, arch rock mass and form grouting reinforcement rock mass (1).

2. under according to claim 1, wear the double-deck advance support structure in cheuch tunnel, it is characterized in that:

The extrapolation angle of ductule (5) is greater than the extrapolation angle of self-advancing type pipe canopy (4).