阅读说明：本技术 一种适于山地施工垂直交叉隧道施工方法 (Vertical cross tunnel construction method suitable for mountain construction ) 是由 王岩 李金会 赵耀 张立强 任利军 瞿晗 吴鸿 马龙祥 于 2020-12-01 设计创作，主要内容包括：本发明公开了一种适于山地施工垂直交叉隧道施工方法,其包括：根据现场工况确定开挖参数并测量放线；开挖小截面隧道至大截面隧道的临时通道,设置隧道支护至大截面隧道开挖轮廓线；沿临时通道转弯开挖,使其与大截面隧道的中轴线重合以形成导洞,沿导洞爬坡开挖至大截面隧道的拱顶；导洞与大截面隧道的中线及拱顶重合后,在三个循环进尺内向大截面隧道的两侧渐变扩挖至隧道侧墙轮廓线；将导洞渐变段扩挖至大截面隧道的断面,反向开挖并布点进行初期支护监测。本发明提供的施工方法,通过开挖导洞使其与大截面隧道中线及拱顶重合,反向扩挖至大截面隧道的轮廓线,从而在不影响施工进度的情况下实现隧道交叉口处快速、安全建造。(The invention discloses a construction method of a vertical cross tunnel suitable for mountain construction, which comprises the following steps: determining excavation parameters according to the site working conditions and measuring and setting out; excavating a temporary channel from the small-section tunnel to the large-section tunnel, and arranging a tunnel support to an excavation contour line of the large-section tunnel; turning and excavating along the temporary channel to ensure that the temporary channel is overlapped with the central axis of the large-section tunnel to form a pilot tunnel, and climbing along the pilot tunnel to excavate to the vault of the large-section tunnel; after the center line and the vault of the pilot tunnel and the large-section tunnel are superposed, gradually expanding and digging to the contour line of the side wall of the tunnel from two sides of the large-section tunnel in the three circulating footings; and expanding and excavating the pilot tunnel transition section to the section of the large-section tunnel, reversely excavating and distributing points for primary support monitoring. According to the construction method provided by the invention, the pilot tunnel is excavated to be superposed with the central line and the vault of the large-section tunnel, and the pilot tunnel is reversely expanded and excavated to the contour line of the large-section tunnel, so that the rapid and safe construction of the tunnel intersection is realized under the condition that the construction progress is not influenced.)

1. A vertical cross tunnel construction method suitable for mountain construction is characterized by comprising the following steps:

step one, determining excavation parameters according to site working conditions and measuring and setting out;

secondly, excavating a temporary channel from the small-section tunnel to the large-section tunnel, and arranging a tunnel support to an excavation contour line of the large-section tunnel;

thirdly, turning and excavating along the temporary channel to enable the temporary channel to be overlapped with the central axis of the large-section tunnel to form a pilot tunnel, and climbing along the pilot tunnel to excavate to the vault of the large-section tunnel;

after the center line and the vault of the pilot tunnel and the large-section tunnel are superposed, gradually expanding and excavating to the contour lines of the side walls of the tunnel from two sides of the large-section tunnel in the three circulating footings;

and fifthly, excavating reversely along the large-section tunnel and distributing points to carry out primary support monitoring.

2. The method for constructing the vertical cross tunnel suitable for mountain construction according to claim 1, wherein an i-beam support is provided at an intersection of the small-section tunnel and the large-section tunnel for reinforcement.

3. The method for constructing the vertical cross tunnel suitable for the mountain construction according to claim 1, wherein in the third step, a supporting structure is constructed by excavating and erecting a climbing slope along the pilot tunnel.

4. The method of claim 3, wherein the excavation is performed in the direction of the pilot tunnel by a bench method, and after a bench section is formed, a supporting structure of a portion to be excavated is removed.

5. The method of claim 1, wherein the pilot tunnel climbing excavation, the gradual enlarging excavation and the reverse excavation are performed within a design excavation profile.

6. The vertical cross tunnel construction method suitable for mountain construction according to claim 5, wherein the climbing angle is 5-15 ° when the pilot tunnel is excavated in a climbing mode.

7. The vertical cross tunnel construction method for mountainous region construction according to claim 6, wherein a climbing angle is 9 ° when the pilot tunnel is excavated in a climbing manner.

8. The method for constructing the vertical cross tunnel suitable for the mountain construction as claimed in claim 2, wherein the i-steel supports comprise lateral supports and diagonal supports, the lateral supports are arranged at an upper side of an intersection of the small-section tunnel and the large-section tunnel, and the diagonal supports are arranged at a lower side of the lateral supports and symmetrically arranged at both sides of the small-section tunnel.

9. The method for constructing the vertical cross tunnel suitable for the mountain construction as claimed in claim 8, wherein the I-shaped steel supports further comprise arc-shaped beams, the arc-shaped beams are arranged at the intersection of the small-section tunnel and the large-section tunnel, and the oblique supports are tangentially arranged at two sides of the arc-shaped beams.

10. The vertical cross tunnel construction method for mountain construction according to claim 1, wherein the temporary pathway is a traffic pathway having a sectional size matched to a transportation vehicle.

Technical Field

The invention belongs to the technical field of building engineering, and relates to a vertical cross tunnel construction method suitable for mountain construction.

Background

With the acceleration of urban modern construction, underground space utilization becomes a trend hotspot. During tunnel design, cross tunnels often appear due to consideration of structural design or functional requirements, and tunnel intersection construction often has a large safety risk, so that the construction often adopts complicated construction modes such as a traditional straight line large-package method and a main tunnel continuous top-picking method, and the construction period is relatively short.

The traditional straight line large-package method and the main hole continuous top-lifting method have the condition exceeding the designed excavation contour line. In the process of expanding and excavating small holes into large holes, on one hand, the top-lifting excavation is limited to be completed in a short area, so that the expanded and excavated external inserting angle is increased, in addition, the operation space of a drill rod of the rock drill is limited, the external inserting angle is more difficult to control, the arch-top overexcavation is easy to occur in the continuous top-lifting excavation, personnel are difficult to observe the surrounding rock situation above the top of the head, and if the block falling situation occurs, the object striking potential safety hazard is easy to occur; on the other hand, when the traditional construction method is used, because the expanding excavation direction is consistent with the excavation direction of the face, the face has almost no footage when expanding excavation.

Therefore, a vertical cross tunnel construction method suitable for mountain construction needs to be designed to solve the technical problems in the prior art.

Disclosure of Invention

The invention aims to solve at least part of technical problems in the prior art to a certain extent, and provides a vertical cross tunnel construction method suitable for mountain construction, which has a reasonable structure, and realizes quick and safe construction of a tunnel intersection without influencing the construction progress by excavating a pilot tunnel to ensure that the pilot tunnel is superposed with a central line and a vault of a large-section tunnel and reversely expanding and excavating to a contour line of the large-section tunnel.

In order to solve the technical problem, the invention provides a vertical cross tunnel construction method suitable for mountain construction, which comprises the following steps:

step one, determining excavation parameters according to site working conditions and measuring and setting out;

secondly, excavating a temporary channel from the small-section tunnel to the large-section tunnel, and arranging a tunnel support to an excavation contour line of the large-section tunnel;

thirdly, turning and excavating along the temporary channel to enable the temporary channel to be overlapped with the central axis of the large-section tunnel to form a pilot tunnel, and climbing along the pilot tunnel to excavate to the vault of the large-section tunnel;

after the center line and the vault of the pilot tunnel and the large-section tunnel are superposed, gradually expanding and excavating to the contour lines of the side walls of the tunnel from two sides of the large-section tunnel in the three circulating footings;

and fifthly, excavating reversely along the large-section tunnel and distributing points to carry out primary support monitoring.

As a preferred embodiment, I-shaped steel supports are arranged at the intersection of the small-section tunnel and the large-section tunnel for reinforcement.

In the third step, a supporting structure is excavated and erected along the slope of the pilot tunnel.

As a preferred embodiment, excavation is carried out along the direction of the pilot tunnel by adopting a step method, and after the section of the step is formed, the supporting structure of the part needing excavation is dismantled.

As a preferred embodiment, the pilot tunnel climbing excavation, the gradual expanding excavation and the reverse excavation are carried out in a designed excavation contour line.

As a preferred embodiment, when the pilot tunnel climbs and excavates, the climbing angle is 5-15 degrees.

In a preferred embodiment, when the pilot tunnel is used for climbing and excavating, the climbing angle is 9 degrees.

As a preferred embodiment, the i-steel support comprises a transverse support and an oblique support, the transverse support is arranged on the upper side of the intersection of the small-section tunnel and the large-section tunnel, and the oblique support is arranged on the lower side of the transverse support and symmetrically arranged on two sides of the small-section tunnel.

As a preferred embodiment, the i-steel support further comprises an arc-shaped beam, the arc-shaped beam is arranged at the intersection of the small-section tunnel and the large-section tunnel, and the oblique supports are tangentially arranged on two sides of the arc-shaped beam.

In a preferred embodiment, the temporary passage is a traffic passage, the cross-sectional dimension of which is matched with that of the transport vehicle.

The invention has the beneficial effects that:

the vertical cross tunnel construction method suitable for mountain construction is reasonable in structure, the pilot tunnel is excavated to be overlapped with the central line and the vault of the large-section tunnel, and the contour line of the large-section tunnel is reversely expanded and excavated, so that the rapid and safe construction of the tunnel intersection is realized under the condition that the construction progress is not influenced.

Drawings

The above advantages of the present invention will become more apparent and more readily appreciated from the detailed description set forth below when taken in conjunction with the drawings, which are intended to be illustrative, not limiting, of the invention and in which:

FIG. 1 is a flow chart of a vertical cross tunnel construction method suitable for mountain construction according to the present invention;

FIG. 2 is a schematic diagram of construction positions corresponding to the construction processes of the present invention;

FIG. 3 is a schematic view of an I-beam support at the intersection of a small cross-section tunnel and a large cross-section tunnel according to the present invention;

FIG. 4 is a schematic view of the present invention for guiding tunnel climbing excavation;

FIG. 5 is a schematic view of the enlarged cross-section of the pilot hole of the present invention.

In the drawings, the reference numerals denote the following components:

10. i-shaped steel support; 11. transversely supporting; 12. obliquely supporting; 13. an arc beam.

Detailed Description

Fig. 1 to 5 are related schematic diagrams of a vertical cross tunnel construction method suitable for mountain land construction according to the present application, and the present invention will be described in detail below with reference to specific embodiments and accompanying drawings.

The examples described herein are specific embodiments of the present invention, are intended to be illustrative and exemplary in nature, and are not to be construed as limiting the scope of the invention. In addition to the embodiments described herein, those skilled in the art will be able to employ other technical solutions which are obvious based on the disclosure of the claims and the specification of the present application, and these technical solutions include technical solutions which make any obvious replacement or modification for the embodiments described herein.

The drawings in the present specification are schematic views to assist in explaining the concept of the present invention, and schematically show the shapes of respective portions and their mutual relationships. It is noted that the drawings are not necessarily to the same scale so as to clearly illustrate the structures of the various elements of the embodiments of the invention. Like reference numerals are used to denote like parts.

The invention relates to a flow chart of a vertical cross tunnel construction method suitable for mountain construction, as shown in figure 1, the vertical cross tunnel construction method suitable for mountain construction comprises the following steps:

step one, determining excavation parameters according to site working conditions and measuring and setting out.

And step two, excavating a temporary channel from the small-section tunnel to the large-section tunnel, and setting a tunnel support to an excavation contour line of the large-section tunnel.

Thirdly, turning and excavating along the temporary channel to enable the temporary channel to be overlapped with the central axis of the large-section tunnel to form a pilot tunnel, and climbing along the pilot tunnel to excavate to the vault of the large-section tunnel; and in the third step, climbing along the pilot tunnel, excavating and building a supporting structure.

And step four, after the center line and the vault of the pilot tunnel and the large-section tunnel are superposed, gradually expanding and excavating to the contour line of the side wall of the tunnel from two sides of the large-section tunnel in the three circulating footings.

And fifthly, excavating reversely along the large-section tunnel and distributing points to carry out primary support monitoring.

According to the invention, simultaneous operation of tunnel face excavation and pilot tunnel expanding excavation is realized, and the construction efficiency is improved on the premise of ensuring the construction safety. The tunnel face in the field is the working face of the tunnel which is continuously pushed forward.

Fig. 2 is a schematic diagram of construction positions corresponding to each construction process in the invention, and a supporting structure is arranged for excavation construction according to the sequence in the construction process.

As an embodiment of the invention, an I-shaped steel support 10 is arranged at the intersection of the small-section tunnel and the large-section tunnel for reinforcement. As shown in fig. 3. The I-steel support 10 comprises a transverse support 11 and an inclined support 12, the transverse support 11 is arranged on the upper side of the intersection of the small-section tunnel and the large-section tunnel, and the inclined support 12 is arranged on the lower side of the transverse support 11 and symmetrically arranged on two sides of the small-section tunnel.

Further, the i-steel support 10 further comprises an arc-shaped beam 13, the arc-shaped beam 13 is arranged at the intersection of the small-section tunnel and the large-section tunnel, and the inclined supports 12 are tangentially arranged on two sides of the arc-shaped beam 13.

As an embodiment of the invention, the included angle between the oblique supports 12 and the transverse supports 11 is 30-60 degrees. Preferably, the angle between the diagonal support 12 and the lateral support 11 is 45 °.

As another embodiment of the present invention, the length of the lateral support 11 is not less than the horizontal dimension of the arc beam 13. Preferably, the length of the transverse support 11 is 200mm to 500mm greater than the horizontal dimension of the arc beam 13.

In the present invention, the arc beam 13 is cast from carbon steel, and the length along the small-section tunnel is 100-300 mm. It will be understood that the lateral support 11 and diagonal support 12 may also be made of channel steel or angle steel.

As an embodiment of the invention, excavation is carried out along the direction of the pilot tunnel by adopting a step method, and after the section of the step is formed, a supporting structure of a part needing excavation is dismantled. And the guide tunnel climbing excavation, the gradual-change expanding excavation and the reverse excavation are carried out in a designed excavation contour line.

Fig. 4 is a schematic diagram of the guide tunnel climbing excavation of the invention, and the climbing angle theta is 5-15 degrees when the guide tunnel climbing excavation is performed. Preferably, when the pilot tunnel climbs and excavates, the climbing angle is 9 °.

According to the invention, the pilot tunnel climbing excavation is enabled to be superposed with the center line and the vault of the large-section tunnel, the length of the flip-top excavation section is effectively increased, and the extrapolation angle of vault excavation is effectively controlled, so that the vault over-excavation amount is reduced.

Fig. 5 is a schematic diagram of the enlarged tunnel excavation cross section of the invention, and the enlarged tunnel excavation needs to gradually progress to the contour line of the side wall of the tunnel from two sides of the large-section tunnel in three circulation footings. According to the invention, through reverse expanding excavation, the influence on the working of the tunnel face is reduced to the greatest extent, the normal excavation working of the tunnel face is ensured, namely the simultaneous working of tunnel face excavation and pilot tunnel expanding excavation is realized, and the pressure of the construction period is reduced.

In the invention, the temporary channel is a vehicle running channel, and the section size of the temporary channel is matched with that of a transport vehicle.

According to the method, the pilot tunnel climbing excavation is carried out in the designed excavation contour line, so that the pilot tunnel climbing excavation is superposed with the central line and the vault of the large-section tunnel, and the extrapolation angle of the vault excavation is effectively controlled, so that the vault excavation excess is reduced, the normal excavation operation of a tunnel face is ensured through reverse expanding excavation, and the construction period pressure is reduced. According to the comparison of the on-site construction arrangement, the construction method can save labor cost, cost caused by vault over-excavation and the like, effectively shorten the construction period and reduce the excavation safety risk.

Compared with the defects and shortcomings of the prior art, the vertical cross tunnel construction method suitable for mountain construction is reasonable in structure, and the whole excavation process is within the designed excavation contour line through the modes of pilot tunnel climbing excavation and reverse expanding excavation. The climbing excavation can be effectively prolonged by the length of the top-picking excavation section, the external inserting angle is effectively controlled, convenience is brought to operators, reverse expanding excavation is carried out after the center line of the small pilot tunnel and the large tunnel coincides with the vault, the influence on the working of the tunnel face can be reduced to the greatest extent, normal excavation of the tunnel is guaranteed, the construction period can be effectively shortened under the condition of guaranteeing safety, smooth implementation of engineering is guaranteed, and reference and guidance are provided for similar engineering.

The present invention is not limited to the above embodiments, and any other products in various forms can be obtained by the teaching of the present invention, but any changes in the shape or structure thereof, which are the same as or similar to the technical solutions of the present invention, fall within the protection scope of the present invention.