Steel formwork for post-cast ring beam of portal without internal support

Abstract

The utility model belongs to the field of building construction, and specifically relates to a portal post-cast ring beam steel formwork without internal support, including an inner formwork and an end formwork; the inner formwork and the end formwork are provided with bolt holes respectively connected to the shield segments and the side walls; the side walls are provided with embedded portal steel rings connected to the end formwork; the end formwork is arranged on the outside of the portal post-cast ring beam and is arranged vertically with the inner formwork. The portal post-cast ring beam steel formwork without internal support of the utility model adopts the embedded portal steel rings in the side walls and the continuous steel plates embedded on the shield segments to be connected to the outer formwork and the inner formwork respectively, so that the steel formwork and the main structure of the station and the segments form a solid whole, thereby resisting the gravity and lateral force during concrete pouring. It does not require internal support reinforcement.

Description

Technical Field

[0001] The utility model belongs to the field of building construction, and in particular relates to a post-cast ring beam steel formwork for a portal without internal support. Background Art

[0002] Shield construction technology is currently the main construction method for building underground intercity railway tunnels. The main structure of the shield tunnel is composed of prefabricated assembled segments and post-cast ring beams connecting the portals. The post-cast ring beams not only connect the stations and sections, but also play an important role in preventing tunnel leakage and enhancing the overall performance of the main structure of the tunnel.

[0003] The post-cast ring beam usually adopts an embedded structure, that is, after removing the zero-ring segment, high-grade concrete is poured within the 0.8-1.2m range of the station side wall structure to connect the section and the station into a whole. As the diameter of the shield tunnel becomes larger and larger, the post-cast ring beam is also getting higher and thicker. If the importance of the construction technology of the post-cast ring beam of the portal is underestimated, it will lead to more serious safety and quality accidents.

[0004] The post-cast ring beam of the portal is usually constructed after the tunnel is penetrated. At present, the most commonly used construction method is to use steel formwork + internal support system ( Figure 1-2 As shown, the inner side of the post-cast ring beam 1' of the portal is connected to the shield segment 4' and the side wall 5', and the outer side is connected to the steel formwork 3', which is supported by the inner support 2'; the steel formwork 3' is customized in the factory, and the inner support 2' is usually composed of a full-height steel pipe bracket and some reinforcement parts. If necessary, it is necessary to add a regulator to the bracket to reduce the deformation of the template. This method has a cumbersome construction process, and it is difficult to control the deformation of the template. The quality of the project is difficult to guarantee. In addition, the full-height bracket blocks the entrance of the tunnel, the battery car group cannot pass, and the shield machine cannot discharge slag. It is not suitable for the situation where the post-cast ring beam and the main tunnel excavation are cross-constructed. Utility Model Content

[0005] The utility model aims to overcome the defects in the prior art and provide a portal post-cast ring beam steel formwork without internal support.

[0006] In order to achieve the above-mentioned purpose, the utility model adopts the following technical solutions:

[0007] A portal post-cast ring beam steel formwork without internal support, comprising an inner formwork and an end formwork; the inner formwork and the end formwork are both provided with bolt holes connected to shield segments and side walls respectively; a pre-buried portal steel ring is provided in the side wall and connected to the end formwork; the end formwork is arranged on the outer side of the portal post-cast ring beam and is arranged perpendicular to the inner formwork.

[0008] The tunnel gate steel ring is L-shaped; the tunnel gate steel ring comprises an inner ring and an end ring; the inner ring is pre-buried in the side wall; the end ring is pre-buried with an end ring nut connected to the end mold.

[0009] The circumferential spacing of the end ring nuts is 3.6°.

[0010] The shield segments are pre-embedded with continuous steel plates; and the segment nuts are pre-embedded with the continuous steel plates.

[0011] The circumferential spacing of the segment nuts is 3.6°.

[0012] Compared with the prior art, the beneficial effects of the utility model are:

[0013] The portal post-cast ring beam steel formwork without internal support of the utility model uses the portal steel ring embedded in the side wall and the continuous steel plate embedded in the shield segment to connect with the outer formwork and the inner formwork respectively, so that the steel formwork, the station main structure and the segment form a solid whole, thereby resisting the gravity and lateral force during concrete pouring. It does not need internal support reinforcement.

[0014] The force principle of the steel formwork structure of the present application is clear, simple and reasonable, with a high safety factor, flexible and fast disassembly and assembly, strong practicality, and high quality controllability; the steel formwork has high rigidity, is not easy to deform, has good form integrity, is neat and beautiful after concrete pouring, and does not require subsequent repairs; the use of the steel formwork of the present application for construction can realize the cross-construction of the post-cast ring beam and the shield machine excavation, and the battery vehicle transportation system can pass normally, which not only speeds up the construction progress of the post-cast ring beam, but also does not delay the shield excavation construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 -2 is a schematic diagram of the structure of the steel formwork for the post-cast ring beam of the portal at the current stage;

[0016] Figure 3 The utility model is a schematic diagram of the overall structure of the post-cast ring beam steel formwork for the tunnel portal. DETAILED DESCRIPTION

[0017] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and the best embodiment.

[0018] Figure 3 A portal post-cast ring beam steel formwork 3 without internal support is shown, comprising an inner formwork 32 and an end formwork 31; the inner formwork 32 and the end formwork 31 are provided with bolt holes respectively connected to the shield segments and the side walls 5; a pre-buried portal steel ring 7 is provided in the side wall 5 and connected to the end formwork 31; the end formwork is arranged on the outer side of the portal post-cast ring beam and is arranged perpendicular to the inner formwork.

[0019] The portal steel ring 7 is L-shaped; the portal steel ring 7 includes an inner ring and an end ring; the inner ring is embedded in the side wall 5; the end ring is embedded with an end ring nut 61 connected to the end mold 31. The axis of the portal steel ring is consistent with the axis of the tunnel; the circumferential spacing of the end ring nuts is 3.6°.

[0020] The shield segment 4 is pre-embedded with a continuous steel plate 8, and the continuous steel plate 8 is pre-embedded with a segment nut 62. The circumferential spacing of the segment nuts 62 is 3.6°.

[0021] The construction method of the portal post-cast ring beam steel formwork without internal support of the present application specifically adopts the following steps:

[0022] (1) During the construction of the station side wall, a portal steel ring 7 is buried in the side wall 5, and a total station is used to measure, lay out and verify the circle center coordinates to ensure that the coordinates are consistent with the tunnel axis and the ellipticity is within the control value;

[0023] (2) The shield machine assembles precast concrete universal segments at the initial stage. When assembling the first ring, the shield segment 4 with embedded continuous steel plate 8 is used. The misalignment of the steel template of the post-cast ring beam of the shield segment without internal support is measured with a right-angle measuring ruler to ensure that the misalignment is not greater than the specification requirements;

[0024] (3) The post-cast ring beam steel formwork 3 is processed and manufactured in the factory, including the inner formwork and the outer formwork, and is manufactured according to the processing drawings provided by the technical personnel to ensure that the bolt hole spacing is consistent with the end ring nut and the segment nut spacing;

[0025] (4) Production, installation and acceptance of ring beam reinforcement and concealed works;

[0026] (5) Mould closing: Tighten the inner formwork and end formwork of the steel formwork to the continuous steel plate 8 and the portal steel ring 7 respectively with Φ22 screws. At this point, the steel formwork support system of the post-cast ring beam of the portal without internal support is completed;

[0027] (6) Finally, pour the concrete.

[0028] In summary, the portal post-cast ring beam steel formwork without internal support of the utility model uses the portal steel ring embedded in the side wall and the continuous steel plate embedded in the shield segment to connect with the outer formwork and the inner formwork respectively, so that the steel formwork, the station main structure and the segment form a solid whole, thereby resisting the gravity and lateral force during concrete pouring. It does not need internal support reinforcement.

[0029] The above contents are only preferred embodiments of the present invention. For ordinary technicians in this field, according to the concept of the present invention, there will be changes in the specific implementation methods and application scopes. The contents of this specification should not be understood as limiting the present invention.

Claims

1. A portal post-cast ring beam steel formwork without internal support, characterized in that: It includes an inner formwork and an end formwork; the inner formwork and the end formwork are both provided with bolt holes connected to the shield segments and the side walls respectively; a pre-buried portal steel ring is provided in the side wall and connected to the end formwork; the end formwork is arranged on the outside of the portal post-cast ring beam and is arranged perpendicular to the inner formwork.

2. The portal post-cast ring beam steel formwork without internal support according to claim 1 is characterized in that: The tunnel gate steel ring is L-shaped; the tunnel gate steel ring comprises an inner ring and an end ring; the inner ring is pre-buried in the side wall; the end ring is pre-buried with an end ring nut connected to the end mold.

3. The portal post-cast ring beam steel formwork without internal support according to claim 2 is characterized in that: The circumferential spacing of the end ring nuts is 3.6°.

4. The portal post-cast ring beam steel formwork without internal support according to claim 1 is characterized in that: The shield segments are pre-embedded with continuous steel plates; and segment nuts are pre-embedded with the continuous steel plates.

5. The portal post-cast ring beam steel formwork without internal support according to claim 4 is characterized in that: The circumferential spacing of the segment nuts is 3.6°.

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