阅读说明：本技术 一种在建隧道单侧加宽开挖支护结构及其施工办法 (Excavation supporting structure widened on one side of tunnel under construction and construction method thereof ) 是由 包特门白乙拉 吕鑫 姚景武 郑永飞 赵耀 王江滔 杨伟光 程稳征 霍俊晨 刘俊奇 于 2020-03-23 设计创作，主要内容包括：本发明公开了一种在建隧道单侧加宽开挖支护结构及其施工办法,用于解决在建隧道单侧加宽施工开挖、初支问题,其采用背拱和弧形竖向支撑临时加固原隧道初支部分,以便加强原隧道空间受力状态,根据弧形竖向钢支撑把隧道开挖断面分成六个断面,把现隧道初支拆除和新隧道开挖、支护施工顺序为中心线上部、中心线下部、临空面上部、临空面下部、加宽面上部、加宽面下部等,大原则为哪一段受力大,优先施工那一段,以达到在建隧道单侧加宽时受力合理、有效减低施工安全风险,工序转换合理,提高了施工效率,保证了施工进度。(The invention discloses a widened excavation supporting structure for a single side of a tunnel under construction and a construction method thereof, which are used for solving the problems of widened construction excavation and primary support for the single side of the tunnel under construction.)

1. The utility model provides a widen excavation supporting construction in tunnel unilateral under construction, includes by old tunnel main tunnel upper right half section, old tunnel main tunnel lower right half section, old tunnel main tunnel upper left half section and old tunnel main tunnel lower left half section four regional old tunnel main tunnel (16) of constituteing, its characterized in that: the tunnel comprises a tunnel main hole (11) consisting of an upper right half section of an old tunnel main hole, a lower right half section of the old tunnel main hole, an upper left half section of the old tunnel main hole, a lower left half section of the old tunnel main hole, an upper widening surface and a lower widening surface of a widening side, a plurality of back arches (4) are arranged in the old tunnel main hole (16) at equal intervals, an upper half primary support (5) of the new tunnel main hole is arranged in the upper right half section area of the old tunnel main hole, a vertically arranged arc-shaped vertical upper support (1) and a horizontally arranged vertical support transverse connecting piece (3) are arranged, a lower half primary support (6) of the new tunnel main hole is arranged in the lower right half section area of the old tunnel main hole, an arc-shaped vertical lower support (2) is vertically arranged, an upper half primary support (7) of the new tunnel main hole is arranged in the upper left half section area of the old tunnel main hole, a lower half section area of the new tunnel primary hole primary lower half support (8) is arranged in the lower left half section area of the old tunnel main hole, and an upper half primary support (9) at the upper part of the new tunnel main hole widening surface and a lower half primary support (10) at the lower part of the new tunnel main hole widening surface are respectively arranged on the upper widening surface and the lower widening surface.

2. The single-side widening excavation supporting structure for the tunnel under construction and the construction method thereof according to claim 1, wherein: six areas, namely the upper right half section of the old tunnel main hole, the lower right half section of the old tunnel main hole, the upper left half section of the old tunnel main hole, the lower left half section of the old tunnel main hole, the upper widening surface and the lower widening surface of the widening side are separated by the middle line of the arc-shaped vertical upper support (1), the arc-shaped vertical lower support (2) and the vertical support transverse connecting piece (3).

3. The single-side widening excavation supporting structure for the tunnel under construction and the construction method thereof according to claim 1, wherein: the shape of the back arch (4) is the same as the shape of the original primary support of the old tunnel main hole (16), and the back arch is tightly attached to the original primary support.

4. The single-side widening excavation supporting structure for the tunnel under construction and the construction method thereof according to claim 1, wherein: the back arch (4) is of a profile steel structure, the back arch and the back arch are welded by adopting deformed steel bars, and the bottom arch springing of the back arch (4) is positioned on the cushion layer.

5. The single-side widening excavation supporting structure for the tunnel under construction and the construction method thereof according to claim 1, wherein: the upper half primary support (5) of the new tunnel main hole, the lower half primary support (6) of the new tunnel main hole, the upper half primary support (7) of the new tunnel main hole facing empty surface, the lower half primary support (8) of the new tunnel main hole facing empty surface, the upper half primary support (9) of the new tunnel main hole widened surface upper portion and the lower half primary support (10) of the new tunnel main hole widened surface lower portion all adopt a profile steel structure.

6. The single-side widening excavation supporting structure for the tunnel under construction and the construction method thereof according to claim 1, wherein: arc vertical upper support (1), arc vertical lower support (2) and vertical support transverse connection spare (3) all adopt the shaped steel structure, arc vertical upper support (1) and arc vertical lower support (2) and new tunnel main hole first (5), new tunnel main hole second first (6), new tunnel main hole face empty face first (7), new tunnel main hole face empty face second first (8), new tunnel main hole widen first (9) on face upper portion and new tunnel main hole widen the junction of face lower part first (10) and adopt bolted connection.

7. The utility model provides a widen excavation supporting construction's construction method in tunnel unilateral under construction which characterized in that: the method comprises the following steps:

s1: mounting the back arches (4) on the primary supports of the old tunnel at equal intervals;

s2: dismantling the upper right half primary support (12) of the old tunnel main hole, supporting the upper half primary support (5) of the new tunnel main hole after excavation, and installing an arc-shaped vertical upper support (1) and a vertical support transverse connecting piece (3);

s3: dismantling the lower right half primary support (13) of the old tunnel main tunnel, supporting the lower half primary support (6) of the new tunnel main tunnel after excavation, and installing an arc-shaped vertical lower support (2);

s4: removing the upper left half primary support (14) of the old tunnel main tunnel, and supporting the upper half primary support (7) of the free face of the new tunnel main tunnel after excavation;

s5: removing the left lower half primary support (15) of the old tunnel main tunnel, and supporting the lower half primary support (8) of the free face of the new tunnel main tunnel after excavation;

s6: excavating and supporting an upper widening surface of a widening side of a main tunnel (11) of the new tunnel, and supporting an upper half primary support (9) of the widening surface of the main tunnel of the new tunnel;

s7: excavating and supporting a lower widening surface of a widening side of the main tunnel (11) of the new tunnel, and supporting a lower half primary support (10) of the lower part of the widening surface of the main tunnel of the new tunnel;

s8: and after the deformation of the main tunnel hole (11) is stabilized, the arc-shaped vertical upper support (1), the arc-shaped vertical lower support (2) and the vertical support transverse connecting piece (3) are dismantled and recovered.

8. The construction method for widening the excavation supporting structure on the single side of the tunnel under construction according to claim 7, wherein: and when four parts, namely an upper right half primary support (12) of an old tunnel main hole of the old tunnel main hole (16), a lower right half primary support (13) of the old tunnel main hole, an upper left half primary support (14) of the old tunnel main hole and a lower left half primary support (15) of the old tunnel main hole are removed, the old tunnel main hole is broken and removed by adopting an artificial pneumatic pick chiseling matched machine, when steel materials are removed to the primary support, the steel materials are preferentially cut off, and then the residual concrete is chiseled.

9. The construction method for widening the excavation supporting structure on the single side of the tunnel under construction according to claim 7, wherein: and when the upper widening surface and the lower widening surface of the widening side are excavated, the blasting shape and the blasting parameters are formulated according to the shape of the excavated surface and the monitoring and measuring data.

10. The construction method for widening the excavation supporting structure on the single side of the tunnel under construction according to claim 7, wherein: and the safety distance of the upper half primary support (5) of the new tunnel main hole, the lower half primary support (6) of the new tunnel main hole, the upper half primary support (7) of the empty face of the new tunnel main hole, the lower half primary support (8) of the empty face of the new tunnel main hole, the upper half primary support (9) of the widened face of the new tunnel main hole and the lower half primary support (10) of the widened face of the new tunnel main hole is determined according to the surrounding rock deformation allowance and vault subsidence monitoring measurement data.

Technical Field

The invention relates to the technical field of single-side expanding excavation of tunnels, in particular to a single-side widening excavation supporting structure of a tunnel under construction and a construction method thereof.

Background

With the continuous perfection and mechanization of the tunnel construction technology, the tunnel construction technology can solve a large number of construction problems, and particularly, the tunnel construction technology for special geology is more and more mature. However, the original design can not meet the requirements of upgrading and transforming the future traffic volume, the existing tunnel is a small-clear-distance tunnel, the single-side widening is realized, a mature construction supporting structure and process are not formed in the industry for the single-side expanding excavation construction method of the built tunnel, and the technical safety guarantee measures in the construction are particularly prominent. The original excavation and supporting construction supporting structure and process can not meet the existing requirements, the safety guarantee measures can not be guaranteed, and meanwhile, the utilization rate is greatly reduced.

In view of the defects of the traditional supporting structure and the excavation and supporting construction method, the invention actively carries out research and innovation by depending on years of abundant practical operation experience in the product engineering industry and combining with the application of theoretical knowledge, and designs the unilateral widening excavation supporting structure for the tunnel under construction and the construction method thereof.

Disclosure of Invention

The invention aims to provide a single-side widening excavation supporting structure of a tunnel under construction and a construction method thereof, so as to solve the problems in the background technology.

In order to achieve the purpose, the invention provides the following technical scheme: a widened excavation supporting structure for one side of a tunnel under construction comprises an old tunnel main tunnel consisting of four areas of an old tunnel main tunnel upper right half-section, an old tunnel main tunnel lower right half-section, an old tunnel main tunnel upper left half-section and an old tunnel main tunnel lower left half-section, and also comprises a new tunnel main tunnel consisting of an old tunnel main tunnel upper right half-section, an old tunnel main tunnel lower right half-section, an old tunnel main tunnel upper left half-section, an old tunnel main tunnel lower left half-section, an upper widening surface and a lower widening surface of a widening side, wherein a plurality of back arches are arranged in the old tunnel main tunnel at equal intervals, an upper half primary support of the new tunnel main tunnel is arranged in the old tunnel main tunnel upper right half-section area, an arc vertical upper support and a horizontal support connecting piece are arranged, a lower half support of the new tunnel main tunnel is arranged in the old tunnel main tunnel lower right half-section area, and an arc vertical lower support is arranged, and arranging an upper half primary support of a new tunnel main hole facing empty surface in the upper left half section area of the old tunnel main hole, arranging a lower half primary support of a new tunnel main hole facing empty surface in the lower left half section area of the old tunnel main hole, and respectively installing an upper half primary support of a new tunnel main hole widening surface and a lower half primary support of a new tunnel main hole widening surface on the upper widening surface and the lower widening surface.

Preferably, six areas, namely the upper right half section of the old tunnel main hole, the lower right half section of the old tunnel main hole, the upper left half section of the old tunnel main hole, the lower left half section of the old tunnel main hole and the upper widening surface and the lower widening surface of the widening side are separated by the central line of the arc-shaped vertical upper support, the arc-shaped vertical lower support and the vertical support transverse connecting piece.

Preferably, the shape of the back arch is the same as the shape of the original primary support of the old tunnel main hole, and the back arch is tightly attached to the original primary support.

Preferably, the back arch is of a profile steel structure, the back arch and the back arch are welded by using deformed steel bars, and the arch foot at the bottom end of the back arch is positioned on the cushion layer.

Preferably, the upper half primary support of the new tunnel main hole, the lower half primary support of the new tunnel main hole, the upper half primary support of the new tunnel main hole free face, the lower half primary support of the new tunnel main hole free face, the upper half primary support of the new tunnel main hole widened face upper portion and the lower half primary support of the new tunnel main hole widened face lower portion all adopt a profile steel structure.

Preferably, the arc vertical upper support, the arc vertical lower support and the vertical support transverse connecting piece are all of a profile steel structure, and the joints of the arc vertical upper support and the arc vertical lower support, the upper half of a new tunnel main hole, the lower half of the new tunnel main hole, the upper half of a new tunnel main hole face, the lower half of the new tunnel main hole face, the upper half of a new tunnel main hole widened face and the lower half of the new tunnel main hole widened face are connected through bolts.

A construction method for widening and excavating a supporting structure on one side of a tunnel under construction comprises the following steps:

s1: mounting back arches on the primary supports of the old tunnel at equal intervals;

s2: removing the upper right half primary support of the old tunnel main tunnel, supporting the upper half primary support of the new tunnel main tunnel after excavation, and installing an arc-shaped vertical upper support and a vertical support transverse connecting piece;

s3: removing the lower right half primary support of the old tunnel main tunnel, supporting the lower half primary support of the new tunnel main tunnel after excavation, and installing an arc-shaped vertical lower support;

s4: removing the upper left half primary support of the old tunnel main tunnel, and supporting the upper half primary support of the free face of the new tunnel main tunnel after excavation;

s5: removing the left lower half primary support of the old tunnel main tunnel, and supporting the lower half primary support of the free face of the new tunnel main tunnel after excavation;

s6: excavating and supporting an upper widening surface of a widening side of a main tunnel of the new tunnel, and supporting an upper half primary support of the widening surface of the main tunnel of the new tunnel;

s7: excavating and supporting a lower widening surface of a widening side of a main tunnel of the new tunnel, and supporting a lower half primary support of the lower part of the widening surface of the main tunnel of the new tunnel;

s8: and dismantling and recovering the arc-shaped vertical upper support, the arc-shaped vertical lower support and the vertical support transverse connecting piece after the deformation of the main hole of the new tunnel is stable.

Preferably, when four parts of an old tunnel main hole upper right half primary support of the old tunnel main hole, an old tunnel main hole lower right half primary support, an old tunnel main hole upper left half primary support and an old tunnel main hole lower left half primary support are removed, the four parts are removed by adopting manual pneumatic pick chiseling to match mechanical crushing, when steel materials are removed to the primary support, the steel materials are preferentially cut off, and then the rest concrete is chiseled.

Preferably, the blasting shape and the blasting parameters are formulated according to the excavation surface shape and the monitoring measurement data when the upper widening surface and the lower widening surface of the widening side are excavated.

Preferably, the safety distance of the upper half primary support of the new tunnel main hole, the lower half primary support of the new tunnel main hole, the upper half primary support of the empty face of the new tunnel main hole, the lower half primary support of the empty face of the new tunnel main hole, the upper half primary support of the upper part of the widened face of the new tunnel main hole and the lower half primary support of the lower part of the widened face of the new tunnel main hole is determined according to the surrounding rock deformation allowance and the vault subsidence monitoring measurement data.

Compared with the prior art, the invention has the beneficial effects that:

1. according to the stress condition, the tunnel excavation surface is divided into six sections, so that the space stress effect is reduced;

2. according to the stress magnitude and the danger height, the tunnel excavation sequence is based on the construction of the danger height, the construction is carried out firstly when the danger height is high, the construction is carried out after the danger bottom, and the tunnel support is completed in time to form a section;

3. the tunnel is just propped up and is supported bolted connection between temporarily, strengthens overall stability, ensures construction safety.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a schematic view of the overall construction structure of the present invention.

In the drawings, the components represented by the respective reference numerals are listed below:

1. the arc-shaped vertical upper support; 2. an arc vertical lower support; 3. a vertical support transverse connector; 4. back arching; 5. the upper half of the main tunnel of the new tunnel is primarily supported; 6. the lower half of the main tunnel of the new tunnel is primarily supported; 7. the upper half of the empty face of the main hole of the new tunnel is primarily supported; 8. the lower half of the empty face of the main hole of the new tunnel is primarily supported; 9. the upper half primary support of the new tunnel main hole widened surface; 10. the lower half primary support of the lower part of the widened surface of the main tunnel of the new tunnel; 11. a new tunnel main hole; 12. the upper right half primary support of the old tunnel main hole; 13. the lower right half primary support of the old tunnel main tunnel; 14. the upper left half of the main tunnel of the old tunnel is primarily supported; 15. the left lower half primary support of the old tunnel main hole; 16. and (5) main holes of the old tunnel.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1-2, the present invention provides a technical solution: a widened excavation supporting structure for one side of a tunnel under construction, as shown in a dotted line part of figure 2, an old tunnel main hole 16 consisting of four areas of an old tunnel main hole upper right half-section, an old tunnel main hole lower right half-section, an old tunnel main hole upper left half-section and an old tunnel main hole lower left half-section, and a new tunnel main hole 11 consisting of an old tunnel main hole upper right half-section, an old tunnel main hole lower right half-section, an old tunnel main hole upper left half-section, an old tunnel main hole lower left half-section, an upper widening surface and a lower widening surface of a widening side, wherein a plurality of back arches 4 are arranged in the old tunnel main hole 16 at equal intervals, and the shape of each back arch 4 is the same as that of an original tunnel main hole 16 and is tightly attached to the original support; the back arch 4 is of a profile steel structure and is welded with each other by adopting deformed steel bars, and the bottom arch foot of the back arch 4 is positioned on the cushion layer. Old tunnel main hole upper right half section region set up new tunnel main hole upper half and just prop 5 to install the vertical upper support of arc 1 of vertical setting and the vertical braces transverse connection piece 3 of horizontal setting old tunnel main hole lower right half section region set up new tunnel main hole lower half and just prop 6 to vertically install vertical under bracing of arc 2, six regions of upper portion widen face and the lower portion widen face of old tunnel main hole upper right half section, old tunnel main hole lower right half section, old tunnel main hole upper left half section, old tunnel main hole lower left half section and widen side are separated through the vertical central line that upwards supports 1, vertical under bracing of arc 2 and vertical braces transverse connection piece 3 of arc. And arranging an upper half primary support 7 of a new tunnel main hole facing empty surface in the upper left half section area of the old tunnel main hole, arranging a lower half primary support 8 of the new tunnel main hole facing empty surface in the lower left half section area of the old tunnel main hole, and respectively installing an upper half primary support 9 of a new tunnel main hole widening surface and a lower half primary support 10 of a new tunnel main hole widening surface on the upper widening surface and the lower widening surface.

Wherein, the upper half primary support 5 of the new tunnel main hole, the lower half primary support 6 of the new tunnel main hole, the upper half primary support 7 of the new tunnel main hole face, the lower half primary support 8 of the new tunnel main hole face, the upper half primary support 9 of the new tunnel main hole widening face upper part and the lower half primary support 10 of the new tunnel main hole widening face lower part all adopt a profile steel structure.

The novel tunnel is characterized in that the arc vertical upper support 1, the arc vertical lower support 2 and the vertical support transverse connecting piece 3 are all of a profile steel structure, the vertical support arc is obtained by calculation according to stress generated in tunnel construction and rock mass pressure, and the joints of the arc vertical upper support 1 and the arc vertical lower support 2, the upper half primary support 5 of the new tunnel main hole, the lower half primary support 6 of the new tunnel main hole, the upper half primary support 7 of the new tunnel main hole facing empty surface, the lower half primary support 8 of the new tunnel main hole facing empty surface, the upper half primary support 9 of the new tunnel main hole widened surface upper portion and the lower half primary support 10 of the new tunnel main hole widened surface are connected through bolts.

A construction method for widening and excavating a supporting structure on one side of a tunnel under construction comprises the following steps:

s1: after the construction of the advanced large pipe shed of the new tunnel, installing a plurality of arc-shaped back arches 4 on the primary support of the old tunnel at equal intervals, and measuring the arcs at the installation part before installation to ensure that the back arches 4 are tightly attached to the primary support of the old tunnel;

s2: and (3) removing the upper half primary support 12 of the main hole of the old tunnel by adopting a breaking hammer and manual cooperation, and preferentially cutting the reinforcing mesh and the connecting ribs when the reinforcing mesh or the connecting concrete surface is removed, so as to ensure that the residual concrete can be chiseled after all the reinforcing mesh and the connecting ribs are cut. And cutting the existing reinforcing mesh and connecting ribs by adopting water welding in the process of removing the sprayed concrete. Ensuring that the stress of the existing arch frame is not damaged. And excavating and supporting the upper half primary support 5 of the main tunnel of the new tunnel after the tunnel is dismantled, and reserving a reserved settlement amount after the tunnel is expanded and excavated to a design contour line. After a new tunnel arch frame is installed, installing an arc-shaped vertical upper support 1 and a vertical support transverse connecting piece, and sticking a monitoring measuring chip;

s3: removing the lower right half primary support 13 of the old tunnel main hole, supporting the lower half primary support 6 of the new tunnel main hole after excavation, and installing the arc-shaped vertical lower support 2;

s4: removing the upper left half primary support 14 of the old tunnel main tunnel, and supporting the upper half primary support 7 of the free face of the new tunnel main tunnel after excavation;

s5: removing the lower left half primary support 15 of the old tunnel main tunnel, and supporting the lower half primary support 8 of the free face of the new tunnel main tunnel after excavation;

s6: excavating and supporting an upper widening surface of a widening side of a main tunnel 11 of the new tunnel, and supporting an upper half primary support 9 of the upper part of the widening surface of the main tunnel of the new tunnel;

s7: excavating and supporting a lower widening surface of a widening side of a main tunnel 11 of the new tunnel, and supporting a lower half primary support 10 of the lower part of the widening surface of the main tunnel of the new tunnel;

s8: and after the deformation of the main hole 11 of the new tunnel is stabilized, dismantling and recovering the arc-shaped vertical upper support 1, the arc-shaped vertical lower support 2 and the vertical support transverse connecting piece 3.

For the six excavation surfaces, in order to reduce excavation sections, the construction sequence is that firstly the most stressed part and the weakest part of the arch crown are excavated, then the parts of the adjacent empty surfaces (the upper widening surface and the lower widening surface) of the old tunnel are excavated, and finally the widening part is excavated, so that the primary support and the rock mass stability of the old tunnel are enhanced, and the space stress condition is increased.

When four parts, namely an upper right half primary support 12 of an old tunnel main hole, a lower right half primary support 13 of the old tunnel main hole, an upper left half primary support 14 of the old tunnel main hole and a lower left half primary support 15 of the old tunnel main hole 16 are removed, the old tunnel main hole is broken and removed by adopting a manual pneumatic pick together with machinery, when steel materials are removed to the primary support, the steel materials are preferentially cut off, and the residual concrete can be removed by chiseling after all the steel materials are cut off.

And when the upper widening surface and the lower widening surface of the widening side are excavated, the blasting shape and the blasting parameters are formulated according to the shape of the excavated surface and the monitoring and measuring data.

And the safety distance of the upper half primary support 5 of the new tunnel main hole, the lower half primary support 6 of the new tunnel main hole, the upper half primary support 7 of the empty face of the new tunnel main hole, the lower half primary support 8 of the empty face of the new tunnel main hole, the upper half primary support 9 of the widened face upper part of the new tunnel main hole and the lower half primary support 10 of the widened face lower part of the new tunnel main hole is determined according to the surrounding rock deformation allowance and vault subsidence monitoring measurement data and adjusted in real time.

In the description herein, references to the description of "one embodiment," "an example," "a specific example" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The preferred embodiments of the invention disclosed above are intended to be illustrative only. The preferred embodiments are not intended to be exhaustive or to limit the invention to the precise embodiments disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best utilize the invention. The invention is limited only by the claims and their full scope and equivalents.