Search

CN-121993231-A - UHPC combined structure suitable for tunnel lining reinforcement and construction method

CN121993231ACN 121993231 ACN121993231 ACN 121993231ACN-121993231-A

Abstract

The invention relates to a UHPC combined structure suitable for tunnel lining reinforcement, which comprises a plurality of UHPC arches, UHPC plates, reinforcement cages and planted bars, wherein the UHPC arches, the UHPC plates, the reinforcement cages and the planted bars are longitudinally distributed along a tunnel, the UHPC arches are formed by splicing a plurality of UHPC sections, the UHPC plates are simply supported on the lower flange plates of two adjacent UHPC arches, the UHPC plates are composed of a plurality of UHPC section flat plates, the adjacent UHPC section flat plates are connected through flexible pieces, so that the curve shape of the tunnel is adapted, cast concrete is cast by taking the prefabricated UHPC plates as the bottom to obtain a cast concrete layer, the UHPC arches, the UHPC plates, the cast concrete layer and the existing lining layer form a common stressed whole, so that the reinforcement of the existing lining of the tunnel is realized.

Inventors

  • SU JIAZHAN
  • CHEN ZHIQING
  • ZHENG XIANZHE
  • DENG TAO
  • WANG YUCHEN
  • LIU XIAOFENG
  • ZHANG ZHENGBIN

Assignees

  • 福州大学
  • 福建省高速路桥建设发展有限公司

Dates

Publication Date
20260508
Application Date
20260209

Claims (10)

  1. 1. The UHPC combined structure is characterized by comprising a plurality of UHPC arches (1), UHPC plates (2) and reinforcement cages (3) which are longitudinally distributed along the existing lining layer (4) of the tunnel, wherein the surface of the existing lining layer (4) is provided with planting ribs (5); The UHPC arches (1) are formed by assembling a plurality of I-shaped UHPC sections, the UHPC plates (2) are supported on UHPC arch lower flange plates (13) of two adjacent UHPC arches (1) in front and back, the UHPC plates (2) are composed of a plurality of UHPC section flat plates (21), the adjacent UHPC section flat plates (21) are connected through flexible pieces (22), and the reinforcement cage (3) is arranged on the planting bars (5) on the surface of the existing lining layer (4); Post-cast concrete layer (6) pour in the top of UHPC board (2), post-cast concrete layer (6) after pouring UHPC bow member (1), UHPC board (2) and existing lining layer (4) form the atress in unison, UHPC bow member (1), UHPC board (2) and post-cast concrete layer (6) form existing lining anchor coat jointly.
  2. 2. A UHPC composite structure suitable for tunnel lining reinforcement according to claim 1, characterized in that the concrete is poured with the UHPC board (2) as bottom and towards the side of the existing lining layer (4) to form the post-cast concrete layer (6).
  3. 3. A UHPC composite structure suitable for tunnel lining reinforcement according to claim 1, characterized in that the bead (5) is barb-like.
  4. 4. A UHPC composite structure suitable for tunnel lining reinforcement according to claim 3, characterized in that the reinforcement cage (3) is suspended on the bar (5), the reinforcement cage (3) being further arranged and poured in the existing lining reinforcement layer.
  5. 5. A UHPC composite structure suitable for tunnel lining reinforcement according to claim 1, characterized in that two adjacent UHPC segments are cooperatively connected by means of a connecting piece (8).
  6. 6. A UHPC composite structure suitable for tunnel lining reinforcement according to claim 5, characterized in that the UHPC segments comprise one UHPC dome segment (11) and two UHPC waisted segments (12), the junction between the UHPC dome segment (11) and the UHPC waisted segment (12) being provided with the connection (8); the connecting piece (6) is a Z-shaped bracket; after assembly, the UHPC dome sections (11) are supported on the UHPC waisted sections (12) on both sides.
  7. 7. A UHPC composite structure suitable for tunnel lining reinforcement according to claim 1, characterized in that the bottom of both sides of the UHPC arch (1) is provided with jack stands (7), the jack stands (7) are detachably equipped with jacks (15), and after the UHPC segments are assembled, the UHPC arch (1) is provided with axial pressure by applying the load of the jacks (15).
  8. 8. UHPC composite structure suitable for tunnel lining reinforcement according to claim 1, characterized in that the side of the two UHPC arches (1) facing the UHPC board (2) is provided with pads (9), said pads (9) being mounted inside the UHPC arch lower flange plate (13).
  9. 9. A UHPC composite structure suitable for tunnel lining reinforcement according to any one of claims 1-8, characterized in that the flexible member (22) is a carbon fibre cloth.
  10. 10. A construction method of a UHPC combined structure suitable for tunnel lining reinforcement is characterized by comprising the following steps: Step S1, removing the inner surface of an existing lining layer on a tunnel to be reinforced, which is likely to fall off, and performing roughening and bar planting treatment; s2, prefabricating an I-shaped UHPC vault section and a UHPC arch waist section according to the shape of the inner curve of the existing lining layer of the tunnel to be reinforced; S3, dividing the prefabrication width of the UHPC segment flat plate in a bending-replacing way according to the shape of the inner curve of the existing lining layer of the tunnel to be reinforced, pre-burying flexible material carbon fiber cloth into side dies and bottom dies of two adjacent UHPC segment flat plates in the process of prefabricating the UHPC segment flat plate, and taking out the side dies and the bottom dies after the UHPC plates are poured and molded to form a foldable continuous prefabricated UHPC segment flat plate, so that the UHPC segment flat plate is convenient to transport and install; s4, arranging jack pedestals at the bottoms of the H-shaped UHPC arched waist sections on two sides, and placing the UHPC arched waist sections on the jack pedestals; S5, following an assembly sequence of installing UHPC arch crown sections after installing the UHPC arch crown sections, supporting the UHPC arch crown sections, installing a Z-shaped bracket at the upper end of the UHPC arch crown sections, and supporting the UHPC arch crown sections on the UHPC arch crown sections at the two sides, wherein the UHPC arch crown sections and the UHPC arch crown sections at the two sides form arch-shaped shaft pressure to form a stable installation structure, and after assembly, integrally forming an I-shaped UHPC arch frame, and then enabling the UHPC arch frame to have certain axial pressure by applying jack load, thereby enhancing the bearing capacity of the reinforced existing lining of the tunnel; S6, pouring concrete to a jack pedestal after the jack load is applied, and removing the jack after the concrete reaches the designed target strength, so as to form a plurality of UHPC arches distributed longitudinally along the tunnel; s7, manufacturing a reinforcement cage according to the thickness required by the existing lining reinforcing layer, and hanging the reinforcement cage on the embedded bars installed on the surface of the existing lining reinforcing layer; S8, placing the UHPC segment flat plate from bottom to top into an H-shaped UHPC arch frame lower flange plate, and placing a cushion block on the inner side of the UHPC arch frame lower flange plate so as to prevent the manufactured UHPC plate from sliding down; And S9, pouring concrete into one side of the existing lining layer by taking the UHPC plate as a permanent template to form a post-pouring concrete layer, and connecting the post-pouring concrete layer, the pre-pouring UHPC plate and the post-pouring concrete layer with the existing lining layer into a common stressed whole to realize the reinforcement of the existing lining layer of the tunnel.

Description

UHPC combined structure suitable for tunnel lining reinforcement and construction method Technical Field The invention relates to the technical field of tunnel construction, in particular to a UHPC combined structure suitable for tunnel lining reinforcement and a construction method. Background In recent years, along with the large-scale construction and operation of highway, railway and subway tunnels in China, various quality defects of tunnel lining structures gradually appear under the influence of factors such as terrain environment, construction process and equipment in the long-term use process. Among them, concrete cracking is the most common disease, which not only reduces the bearing capacity of the lining, but also induces secondary diseases such as water leakage. According to the existing research and engineering practice, tunnel lining damage is mainly represented by lining cracks, water leakage, freeze injury, corrosion and the like, wherein the influence of the lining cracks and deformation on the stability of a tunnel structure is most remarkable. At present, the tunnel lining reinforcement mainly adopts a method of pasting (stretching) a steel plate, wherein the method is to paste the steel plate on the inner surface of a duct piece through organic glue, so that the strength and rigidity of the lining can be effectively improved, but the problems of complex construction and high cost exist. Meanwhile, the reinforcing methods have great influence on driving in the tunnel, and traffic needs to be managed in a sealing mode during reinforcing construction. Therefore, in order to solve the problems, the invention provides a UHPC combined structure suitable for tunnel lining reinforcement and a construction method. Disclosure of Invention (1) Technical problem to be solved The invention aims to provide a UHPC combined structure suitable for tunnel lining reinforcement. The invention further aims to provide a construction method of the UHPC combined structure suitable for tunnel lining reinforcement. In view of the defects of the prior art, the invention provides a combined structure of prefabricated UHPC and post-cast concrete, which is suitable for tunnel lining reinforcement, has reasonable structural design, fully utilizes the characteristics of high strength, high durability, high toughness and the like of UHPC (ultra-high performance concrete), combines the prefabricated H-shaped UHPC arch frame with the prefabricated UHPC plate, and is used as a permanent template of a post-cast concrete layer, thereby avoiding the traditional formwork working procedure, furthest reducing the influence on driving in a tunnel, avoiding the rust problem caused by adopting steel structure reinforcement, and having remarkable engineering application value. (2) Technical proposal In order to solve the above technical problem, a first aspect of the present invention provides: the UHPC combined structure is characterized by comprising a plurality of prefabricated I-shaped UHPC arches, UHPC plates and reinforcement cages which are longitudinally distributed along the existing lining layer of the tunnel, wherein the surface of the existing lining layer is provided with planted bars; The UHPC arch is formed by assembling a plurality of I-shaped UHPC sections, the UHPC plates are supported on the lower flange plates of the UHPC arch of two adjacent UHPC arches, the UHPC plates are composed of a plurality of UHPC section flat plates, and the adjacent UHPC section flat plates are connected through flexible pieces; The post-cast concrete layer is poured above the UHPC plate, the post-cast concrete layer, the UHPC arch, the UHPC plate and the existing lining layer form a stressed whole after pouring, and the UHPC arch, the UHPC plate and the post-cast concrete layer form an existing lining reinforcing layer. Preferably, the concrete takes the UHPC plate as the bottom, and forms the post-cast concrete layer after being poured towards one side of the existing lining layer. Preferably, the planting bar is in a barb shape. Preferably, the reinforcement cage is hung on the planted bars, and the reinforcement cage is further arranged and poured in the existing lining reinforcement layer. Preferably, two adjacent UHPC segments are cooperatively connected by a connecting piece. Preferably, the UHPC segment comprises one UHPC dome segment and two UHPC waisted segments, the splice between the UHPC dome segment and the UHPC waisted segment being provided with the connection. Preferably, the connecting piece is a zigzag bracket. Preferably, after assembly, the UHPC dome sections are supported on the UHPC waisted sections on both sides by means of zigzag brackets. Preferably, jack pedestals are arranged at the bottoms of two sides of the UHPC arch frame, jacks are detachably assembled on the jack pedestals, after the UHPC sections are assembled, the UHPC arch frame is enabled to have axial pressure by applying jack loads, so that the