Construction method of open cut tunnel

Abstract

The invention discloses a construction method of an open cut tunnel, and relates to application of the open cut tunnel. Comprising the following steps that a strip-shaped table is built at the vertical position of a tunnel body on one side of a tunnel portal where the tunnel body is built, an arc-shaped groove is excavated in the base face of the other side of the tunnel portal, an inner supporting framework capable of being overturned is manufactured, an inner supporting auxiliary frame is bundled on an overturning frame, a formwork A is demolded to form an arc-shaped tunnel wall, the arc-shaped tunnel wall is overturned, and the arc-shaped groove is filled and leveled up. The template B is removed, the joints are grouted and combined, and the steps are continued to extend the open cut tunnel body; according to the method, the strip-shaped table is built on one side of the tunnel portal, the arc-shaped groove is dug in the other side of the tunnel portal, the arc-shaped groove is used as an arc-shaped outer mold at the top of the arc-shaped tunnel wall to build the arc-shaped tunnel wall capable of being turned over, then the arc-shaped tunnel wall is turned over through a crane and then is connected with the strip-shaped table to form the open cut tunnel, and the inner mold and the outer mold are not suspended when the arc-shaped tunnel wall is built; and template resources are saved, and the concrete is easy to vibrate and does not have the conditions of collapse and false pouring.

Description

Technical Field

[0001] The invention relates to an open-cut tunnel application, in particular to a method for constructing an open-cut tunnel. Background Art

[0002] Tunnel open holes are mainly used for tunnel openings or road cuttings that are subject to collapse, rockfall, rock flow, and mud flow. Sometimes, they are also used as an effective means to treat landslides and other hazards in road cuttings. Traditional methods of tunnel open hole construction generally include cast-in-place construction and prefabricated formwork splicing. Traditional cast-in-place construction generally involves setting up a steel frame where a tunnel open hole is needed, wrapping it with an inner and outer formwork, and pouring concrete between the inner and outer formworks. Since the tops of the inner and outer formworks are both suspended, the heavy tunnel body requires a very complex formwork construction process. The pouring of concrete is also prone to collapse, false pouring, and difficulty in vibration. Not only is the construction quality difficult to guarantee, but it is also time-consuming and labor-intensive, and the precision is not high. During the prefabricated formwork construction, the tunnel open hole to be built needs to be decomposed into modules, and concrete is poured in a different location, and then pulled to the site for splicing. The transportation cost is high and the splicing is difficult. Summary of the invention

[0003] In order to overcome the shortcomings of the background technology, the present invention discloses a method for constructing an open tunnel, by constructing a strip platform on one side of the tunnel entrance, digging an arc groove on the other side of the tunnel entrance, using the arc groove as an arc outer mold on the top of the arc tunnel wall to construct a flippable arc tunnel wall, and then flipping it with a crane and joining it with the strip platform to form a tunnel open hole, so that the inner mold and the outer mold are not suspended in the air when constructing the arc tunnel wall, which not only saves template resources but also makes it easy to vibrate the concrete without collapse or false pouring.

[0004] In order to achieve the above-mentioned object of the invention, the present invention adopts the following technical scheme: A method for constructing an open tunnel comprises the following steps: Step 1: construct a strip platform at the vertical part of the tunnel body on one side of the tunnel opening where the tunnel body is completed: construct a cast-in-place strip platform on the base surface on one side of the tunnel opening where the tunnel body is completed, which connects to the vertical part of the tunnel body and extends along the tunnel body; Step 2: Dig an arc groove on the base surface on the other side of the tunnel opening: dig an arc groove on the base surface on the other side of the tunnel opening opposite to the strip platform, and leave square platforms at both ends of one side of the arc groove tunnel opening; Step 3. Fabricate an invertible internal support framework: Use steel bars to fabricate an invertible internal support framework. The internal support framework includes a "冂"-shaped bracket and arc-shaped rods. A swivel ring is provided at one end of the arc-shaped rod, and a lifting ring is provided at the other end of the arc-shaped rod. There are multiple arc-shaped rods which are spaced apart. All the multiple arc-shaped rods are rotatably connected to the cross bar at the top of the "冂"-shaped bracket by means of the swivel rings provided thereon. Multiple support rods are spaced between the multiple arc-shaped rods to connect the multiple arc-shaped rods together. After the combination of the arc-shaped rods and the support rods, an invertible frame is formed; Step 4. Install the internal support framework on the other side of the tunnel entrance: Install the internal support framework on the other side of the tunnel entrance, insert the two ends of the "冂"-shaped bracket into the two platforms along the top of the two platforms, and place the middle part of the invertible frame in the arc-shaped groove; Step 5. Bind an internal support auxiliary framework on the invertible frame: Bind an internal support auxiliary framework on the invertible frame so that its outer contour is the same as the thickness of the tunnel body to form an invertible internal formwork frame; Step 6. Cover the formwork on the outside of the invertible internal formwork frame: On the outside of the internal support auxiliary framework between the part located in the arc-shaped groove and the other end of the invertible internal formwork frame away from the "冂"-shaped bracket, cover formwork A except for the parts in contact with the bottom and side walls of the arc-shaped groove; Step 7. Pour concrete into the invertible internal formwork frame: Pour concrete into the invertible internal formwork frame and vibrate it; Step 8. Remove formwork A to form an arc-shaped tunnel wall: After the concrete poured into the invertible internal formwork frame dries, remove formwork A so that the part of the invertible internal formwork frame where the concrete is poured forms an arc-shaped tunnel wall; Step 9. Flip the arc-shaped tunnel wall: Use a crane to lift the lifting ring so that the arc-shaped tunnel wall rotates around the axis of the swivel ring until the end of the arc-shaped tunnel wall at the end where the lifting ring is located contacts the top of the strip-shaped platform; Step 10. Fill the arc-shaped groove: Fill the arc-shaped groove with backfill soil until it is as flat as the base surface and tamp it; Step 11. Cut off the lifting ring and bind a binding frame outside the "冂"-shaped bracket: Cut off the lifting ring and bind a binding frame outside the "冂"-shaped bracket so that the thickness of the binding frame is the same as the thickness of the internal support auxiliary framework; Step 12. Set formwork B outside the binding frame and the internal support auxiliary framework where concrete has not been poured and pour: Set formwork B outside the binding frame and the remaining internal support auxiliary framework where concrete has not been poured and pour concrete; Step 13. Remove formwork B and grout the joint for combination: Remove formwork B and combine the joint between the arc-shaped tunnel wall and the strip-shaped platform with small-aggregate concrete so that the poured concrete binding frame, arc-shaped tunnel wall and strip-shaped platform form an integral open cut tunnel body. The area surrounded by the open cut tunnel body and the base surface forms an open cut tunnel entrance that penetrates the tunnel entrance. Combine the joint between the open cut tunnel body and the tunnel body with small-aggregate concrete; Step 14. Extend the open cut tunnel body by continuing the above steps: Gradually extend the open cut tunnel body to the required length according to the above steps.

[0005] In the method for constructing an open tunnel, the material of the strip platform in step 1 is reinforced concrete.

[0006] In the method for constructing an open tunnel, in step 2, the arc-shaped groove is compacted by a tamping machine after excavation.

[0007] In the method for constructing an open tunnel, the arc rod in step three is made of steel bars, the swivel at one end of the arc rod and the lifting ring at the other end of the arc rod are both formed by extending the arc rod for a certain length and gripping it, and the connection method of the multiple support rods arranged at intervals between the multiple arc rods is welding.

[0008] In the method for constructing an open tunnel, in step three, a connecting rod is provided between the lifting ring and the other end of the arc rod.

[0009] In the method for constructing an open tunnel, in step five, the outer arc surface of the inner mold frame is turned over to fit the bottom of the arc groove.

[0010] In the above-mentioned method for constructing an open tunnel, in step six, the contact surface of the template A at the contact portion between the template A and the inner supporting auxiliary frame is shaped according to the outer contour of the inner supporting auxiliary frame.

[0011] In the above-mentioned method for constructing an open tunnel, the backfill soil in step 10 can be backfilled with the soil excavated from the arc-shaped groove.

[0012] In the tunnel open hole construction method, in step 12, the template B set outside the tying frame and the inner supporting auxiliary frame of the remaining uncast concrete is shaped according to the outer contour of the tying frame and the inner supporting auxiliary frame of the remaining uncast concrete.

[0013] In the method for constructing an open tunnel of the described tunnel, when it is necessary to extend the open tunnel body in step fourteen, the strip platform provided in the open tunnel body of the next constructed tunnel can be located on one side of the opening of the previous open tunnel, and the curved tunnel wall can be located on the other side of the opening of the previous open tunnel. Then, the curved tunnel wall provided in the open tunnel body of the next constructed tunnel can be located on one side of the opening of the previous open tunnel, and the strip platform can be located on the other side of the opening of the previous open tunnel, that is, the positive and negative settings can be alternately performed.

[0014] Due to the adoption of the above technical solution, the present invention has the following beneficial effects: The method for constructing an open tunnel of the present invention comprises the following steps: constructing a strip platform on one side of a tunnel opening, digging an arc groove on the other side of the tunnel opening, using the arc groove as an arc outer mold on the top of the arc tunnel wall to construct an arc tunnel wall that can be turned over, and then turning it over by a crane and joining it with the strip platform to form an open tunnel of the tunnel, so that both the inner mold and the outer mold are not suspended in the air when constructing the arc tunnel wall, which not only saves template resources but also makes it easy to vibrate concrete without collapse or false pouring. The present invention is reasonably designed and easy to operate, effectively improves the construction accuracy, and effectively improves the construction quality of the open tunnel of the tunnel, which has important promotion significance. Brief Description of the Drawings

[0015] Figure 1 It is a flow chart of the construction steps of the present invention; Figure 2 It is a schematic structural diagram of the first construction step of the present invention; Figure 3 It is a schematic structural diagram of the second construction step of the present invention; Figure 4 It is a schematic structural diagram of the second construction step of the present invention from another angle; Figure 5 It is a schematic structural diagram of the third construction step of the present invention; Figure 6 It is a schematic structural diagram of the fourth construction step of the present invention; Figure 7 It is a schematic structural diagram of the fourth construction step of the present invention from another angle; Figure 8 It is a schematic structural diagram of the fifth construction step of the present invention; Fig. 9 It is a schematic structural diagram of the sixth construction step of the present invention; Fig.10 It is a schematic structural diagram of the seventh construction step of the present invention; Fig.11 It is a schematic structural diagram of the eighth construction step of the present invention; Fig.12 It is a schematic structural diagram of the ninth construction step of the present invention; Fig.13 It is a schematic structural diagram of the tenth construction step of the present invention; Fig.14 It is a schematic structural diagram of the eleventh construction step of the present invention; Fig.15 It is a schematic structural diagram of the twelfth construction step of the present invention; Fig.16 It is a schematic structural diagram of the thirteenth construction step of the present invention.

[0016] In the figures: 1, strip-shaped platform; 2, tunnel body; 3, tunnel entrance; 4, base surface; 5, arc-shaped groove; 6, square platform; 7, "冂"-shaped bracket; 8, swivel ring; 9, inner support framework; 10, support rod; 11, arc-shaped rod; 12, connecting rod; 13, suspension ring; 14, inner support auxiliary framework; 15, formwork A; 16, arc-shaped tunnel wall; 17, open cut tunnel entrance; 18, bundling frame; 19, formwork B; 20, open cut tunnel body. Detailed Description of the Invention

[0017] The technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0018] The present invention can be more specifically explained through the following embodiments. The present invention is not limited to the following embodiments. The purpose of disclosing the present invention is to protect all changes and improvements within the scope of the present invention; Combined with the attached Figures 1 to 16 The construction method of the above-mentioned open cut tunnel of a tunnel includes the following steps: Step 1: Build a strip platform at the vertical part of the tunnel body on one side of the tunnel entrance after the completion of the tunnel body construction: On the base surface 4 on one side of the tunnel entrance 3 after the completion of the tunnel body 2 construction, pour a cast-in-place strip platform 1 that connects to the vertical part of the tunnel body 2 and extends along the tunnel body 2. The material of the strip platform 1 is reinforced concrete; Step 2: Excavate an arc-shaped groove on the base surface on the other side of the tunnel entrance: Excavate an arc-shaped groove 5 on the base surface 4 on the other side of the tunnel entrance 3 opposite to the strip platform 1, and leave square platforms 6 at both ends on the side of the tunnel entrance 3 of the arc-shaped groove 5. After the excavation of the arc-shaped groove 5, the inside of the arc-shaped groove 5 is tamped with a rammer; Step 3: Fabricate an inner support framework that can be flipped: Use steel bars to fabricate an inner support framework 9 that can be flipped. The inner support framework 9 includes a "冂"-shaped bracket 7 and arc-shaped rods 11. A rotating ring 8 is provided at one end of the arc-shaped rod 11, and a lifting ring 13 is provided at the other end of the arc-shaped rod 11. The arc-shaped rods 11 are multiple and arranged at intervals. All the multiple arc-shaped rods 11 are rotatably connected to the cross bar at the top of the "冂"-shaped bracket 7 by using the rotating rings 8 provided thereon. Multiple support rods 10 are arranged at intervals between the multiple arc-shaped rods 11 to connect the multiple arc-shaped rods 11 together. The arc-shaped rods 11 and the support rods 10 are combined to form a flipping frame. The material of the arc-shaped rods 11 is steel bars. The rotating ring 8 at one end of the arc-shaped rod 11 and the lifting ring 13 at the other end of the arc-shaped rod 11 are both formed by extending a section of the arc-shaped rod 11 and bending it. The connection method of the multiple support rods 10 arranged at intervals between the multiple arc-shaped rods 11 is welding. A connecting rod 12 is provided between the lifting ring 13 and the other end of the arc-shaped rod 11; Step 4: Set the inner support framework on the other side of the tunnel entrance: Set the inner support framework 9 on the other side of the tunnel entrance, so that the two ends of the "冂"-shaped bracket 7 are inserted into the two square platforms 6 along the tops of the two square platforms 6, and the middle part of the flipping frame is placed in the arc-shaped groove 5; Step Five: Tie the inner support auxiliary frame on the turnover frame: Tie the inner support auxiliary frame 14 on the turnover frame so that its outer contour is the same as the thickness of the tunnel body 2 to form a turnover inner formwork frame, and the outer arc surface of the turnover inner formwork frame fits the bottom of the arc-shaped groove 5; Step Six: Cover the formwork outside the turnover inner formwork frame: Outside the inner support auxiliary frame 14 between the inside of the arc-shaped groove 5 and the other end of the turnover inner formwork frame away from the "冂"-shaped support 7, cover the formwork A15 except for the parts in contact with the bottom and side walls of the arc-shaped groove 5. The contact surface of the formwork A15 in contact with the inner support auxiliary frame 14 is shaped according to the outer contour of the inner support auxiliary frame 14; Step Seven: Pour concrete into the turnover inner formwork frame: Inject concrete into the turnover inner formwork frame and vibrate it; Step Eight: Remove the formwork A to form an arc-shaped tunnel wall: After the concrete poured into the turnover inner formwork frame dries, remove the formwork A so that the poured part of the turnover inner formwork frame forms an arc-shaped tunnel wall 16; Step Nine: Flip the arc-shaped tunnel wall: Use a crane to lift the lifting ring 13 so that the arc-shaped tunnel wall 16 rotates around the axis of the swivel ring 8 until the end of the arc-shaped tunnel wall 16 at one end of the lifting ring 13 contacts the top of the strip platform 1; Step Ten: Fill the arc-shaped groove: Fill the arc-shaped groove 5 with backfill soil until it is as flat as the base surface 4 and tamp it. The backfill soil can be the soil excavated from the excavation of the arc-shaped groove 5; Step Eleven: Cut off the lifting ring and tie the tying frame outside the "冂"-shaped support: Cut off the lifting ring 13 and tie the tying frame 18 outside the "冂"-shaped support 7 so that the thickness of the tying frame 18 is the same as the thickness of the inner support auxiliary frame 14; Step Twelve: Set the formwork B outside the tying frame and the inner support auxiliary frame without poured concrete and pour: Set the formwork B19 outside the tying frame 18 and the remaining inner support auxiliary frame 14 without poured concrete and pour concrete. The formwork B19 set outside the tying frame 18 and the remaining inner support auxiliary frame 14 without poured concrete is shaped according to the outer contours of the tying frame 18 and the remaining inner support auxiliary frame 14 without poured concrete; Step Thirteen: Remove the formwork B and grout the joint for combination: Remove the formwork B19 and combine the joint between the arc-shaped tunnel wall 16 and the strip platform 1 with small-aggregate concrete so that the poured concrete tying frame 18, arc-shaped tunnel wall 16 and strip platform 1 form an integral open-cut tunnel body 20. The area surrounded by the open-cut tunnel body 20 and the base surface 4 forms an open-cut tunnel entrance 17 that penetrates the tunnel entrance 3. Combine the joint between the open-cut tunnel body 20 and the tunnel body 2 with small-aggregate concrete; Step 14, continue with the above steps to extend the open hole body: gradually extend the open hole body 20 to the required length according to the above steps. When it is necessary to extend the open hole body 20, the strip platform 1 provided in the next open hole body 20 to be constructed can be located on one side of the hole opening 17 of the previous open hole, and the curved hole wall 16 can be located on the other side of the hole opening 17 of the previous open hole. Then, the curved hole wall 16 provided in the next open hole body 20 to be constructed can be located on one side of the hole opening 17 of the previous open hole, and the strip platform 1 can be located on the other side of the hole opening 17 of the previous open hole, that is, the positive and negative settings can be alternated.

[0019] The parts not described in detail in this invention are prior art.

Claims

1. A method for constructing an open tunnel, characterized in that: It includes the following steps: Step 1, construct a strip platform on the vertical part of the tunnel body at one side of the tunnel entrance after the tunnel body of the tunnel is completed: construct a cast-in-place strip platform (1) that connects to the vertical part of the tunnel body (2) and extends along the tunnel body (2) on the base surface (4) at one side of the tunnel entrance (3) after the tunnel body (2) of the tunnel is completed; Step 2, excavate an arc-shaped groove on the base surface on the other side of the tunnel entrance: excavate an arc-shaped groove (5) on the base surface (4) on the other side of the tunnel entrance (3) opposite to the strip platform (1), and leave square platforms (6) at both ends on the side of the tunnel entrance (3) of the arc-shaped groove (5); Step 3, fabricate an inner support framework that can be flipped: fabricate an inner support framework (9) that can be flipped with steel bars. The inner support framework (9) includes a "冂”-shaped bracket (7) and arc-shaped rods (11). A swivel ring (8) is provided at one end of the arc-shaped rod (11), and a lifting ring (13) is provided at the other end of the arc-shaped rod (11). The arc-shaped rods (11) are multiple and arranged at intervals. The multiple arc-shaped rods (11) are all rotatably connected to the cross bar at the top of the "冂”-shaped bracket (7) by using the swivel rings (8) provided thereon. Multiple support rods (10) are arranged at intervals between the multiple arc-shaped rods (11) to connect the multiple arc-shaped rods (11) together. The arc-shaped rods (11) and the support rods (10) are combined to form a flipping frame; Step 4, set the inner support framework on the other side of the tunnel entrance: set the inner support framework (9) on the other side of the tunnel entrance, so that both ends of the "冂”-shaped bracket (7) are inserted into the two square platforms (6) along the top of the two square platforms (6), and the middle part of the flipping frame is placed in the arc-shaped groove (5); Step 5, tie an inner support auxiliary framework on the flipping frame: tie an inner support auxiliary framework (14) on the flipping frame so that its outer contour is the same as the thickness of the tunnel body (2) to form a flipping inner formwork frame; Step 6, cover the formwork outside the flipping inner formwork frame: cover formwork A (15) outside the inner support auxiliary framework (14) between the part in the arc-shaped groove (5) and the other end of the flipping inner formwork frame away from the "冂”-shaped bracket (7), except for the part in contact with the bottom and side walls of the arc-shaped groove (5); Step 7, pour concrete into the flipping inner formwork frame: inject concrete into the flipping inner formwork frame and vibrate it; Step 8, remove the formwork of formwork A to form an arc-shaped tunnel wall: after the concrete poured into the flipping inner formwork frame dries, remove the formwork of formwork A so that the part of the flipping inner formwork frame where the concrete is poured forms an arc-shaped tunnel wall (16); Step 9, flip the arc-shaped tunnel wall: use a crane to lift the lifting ring (13) so that the arc-shaped tunnel wall (16) flips with the axis of the swivel ring (8) as the center of the circle until the end of the arc-shaped tunnel wall (16) at the end where the lifting ring (13) is located contacts the top of the strip platform (1); Step 10, fill and level the arc-shaped groove: fill the arc-shaped groove (5) with backfill soil until it is as flat as the base surface (4) and tamp it; Step 11, cut off the lifting ring and tie a tying frame outside the "冂”-shaped bracket: cut off the lifting ring (13) and tie a tying frame (18) outside the "冂”-shaped bracket (7) so that the thickness of the tying frame (18) is the same as the thickness of the inner support auxiliary framework (14); Step 12: Setting formwork B outside the tying frame and the inner supporting auxiliary frame where concrete has not been poured, and pouring concrete: Setting formwork B (19) outside the tying frame (18) and the inner supporting auxiliary frame (14) where concrete has not been poured, and pouring concrete; Step 13, removing the template B and grouting the joints: removing the template B (19), grouting the joints between the arc-shaped tunnel wall (16) and the strip platform (1) with small aggregate concrete, so that the tying frame (18) for pouring concrete, the arc-shaped tunnel wall (16) and the strip platform (1) form an integrated open tunnel body (20), and the area surrounded by the open tunnel body (20) and the base surface (4) forms an open tunnel opening (17) that penetrates the tunnel opening (3), and grouting the joints between the open tunnel body (20) and the tunnel body (2) with small aggregate concrete; Step 14: Continue with the above steps to extend the body of the open hole: follow the above steps to gradually extend the body of the open hole (20) to the required length.

2. The method for constructing an open tunnel according to claim 1, characterized in that: The material of the strip table (1) in step 1 is reinforced concrete.

3. The method for constructing an open tunnel according to claim 1, characterized in that: In step 2, the arc-shaped groove (5) is compacted by a tamping machine after excavation.

4. The method for constructing an open tunnel according to claim 1, characterized in that: In step 3, the material of the arc rod (11) is steel bar, the swivel (8) at one end of the arc rod (11) and the lifting ring (13) at the other end of the arc rod (11) are both formed by extending the arc rod (11) for a certain length and gripping it, and the connection method of the plurality of support rods (10) arranged at intervals between the plurality of arc rods (11) is welding.

5. The method for constructing an open tunnel according to claim 4, characterized in that: In step three, a connecting rod (12) is provided between the lifting ring (13) and the other end of the arc-shaped rod (11).

6. The method for constructing an open tunnel according to claim 1, characterized in that: In step 5, the outer arc surface of the inner mold frame is turned over to fit the bottom of the arc groove (5).

7. The method for constructing an open tunnel according to claim 1, characterized in that: In step six, the contact surface of the template A (15) at the contact portion between the template A (15) and the inner supporting auxiliary frame (14) is shaped according to the outer contour of the inner supporting auxiliary frame (14).

8. The method for constructing an open tunnel according to claim 1, characterized in that: The backfill soil in step 10 can be backfilled with the soil excavated from the excavated arc-shaped groove (5).

9. The method for constructing an open tunnel according to claim 1, characterized in that: In step 12, the template B (19) arranged outside the tying frame (18) and the inner supporting auxiliary frame (14) of the remaining uncast concrete is shaped according to the outer contours of the tying frame (18) and the inner supporting auxiliary frame (14) of the remaining uncast concrete.

10. The method for constructing an open tunnel according to claim 1, characterized in that: When it is necessary to extend the open hole body (20) in step 14, the strip platform (1) provided in the next open hole body (20) to be constructed can be located on one side of the opening (17) of the previous open hole, and the arc-shaped cave wall (16) can be located on the other side of the opening (17) of the previous open hole, and then the arc-shaped cave wall (16) provided in the next open hole body (20) to be constructed can be located on one side of the opening (17) of the previous open hole, and the strip platform (1) can be located on the other side of the opening (17) of the previous open hole, that is, the positive and negative settings can be alternately performed.

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