CN-224228683-U - City door opening type tunnel supporting structure

CN224228683UCN 224228683 UCN224228683 UCN 224228683UCN-224228683-U

Abstract

The utility model provides a gate tunnel supporting structure, which belongs to the technical field of pavement construction and comprises a primary spraying concrete layer, anchor rods, a steel arch, steel mesh sheets and a transverse support section steel, wherein the primary spraying concrete layer is positioned on the surface of an excavation structure surface, the anchor rods are arranged around the excavation structure surface at certain intervals, the steel arch is positioned on the surface of the primary spraying concrete layer and is formed by vertically fixing section steel along the surface of the primary spraying concrete layer, the steel mesh sheets comprise two layers which are respectively arranged on two sides of the steel arch, the composite spraying concrete layer is formed by spraying early high-strength steel fiber concrete for covering an outer layer of the steel mesh sheets, and the transverse support section steel and the bottom of the steel arch form horizontal symmetrical support. According to the utility model, the transverse bracing structure is additionally arranged at the bottom of the steel arch frame, so that the effect of the inverted arch can be achieved, the stability of the lower part of the urban gate-opening section is ensured, and the defect that the inverted arch can be arranged compared with the horseshoe-shaped section is overcome.

Inventors

CAI JINLIN
LU XIAOWEN
LIU TIANYI
LI YUYANG

Assignees

湖北能源集团南漳张家坪抽水蓄能有限公司
湖北能源集团股份有限公司

Dates

Publication Date: 20260512
Application Date: 20250528

Claims (10)

1. The urban gate type tunnel supporting structure is characterized in that the supporting structure is built on an excavation structure surface formed after tunnel excavation is completed and comprises a primary spraying concrete layer, an anchor rod, a reinforcing steel mesh, a steel arch frame, a secondary spraying concrete layer and transverse strut section steel; The primary spraying concrete layer is positioned on the surface of the excavation structure surface and is formed by spraying 3-5 cm thick early high-strength steel fiber concrete on the surface of the excavation profile; The anchor rods are arranged around the excavation structure surface at certain intervals, so that the whole stress of the excavation structure surface is stable; the steel arch is positioned on the surface of the primary spraying concrete layer and is formed by vertically fixing profile steel along the surface of the primary spraying concrete layer; The steel bar net piece comprises two layers, wherein the two layers are respectively arranged on two sides of the steel arch, one layer covers the surface of the primary spraying concrete layer, and the other layer is positioned on the bottom surface of the secondary spraying concrete layer; the re-spraying concrete layer is formed by spraying early high-strength steel fiber concrete covered with an outer layer of reinforcing steel mesh; and the transverse support section steel and the bottom of the steel arch form a horizontal symmetrical support.
2. The urban gate type tunnel supporting structure according to claim 1, wherein the cross-bracing section comprises i-steel, H-steel or channel steel, and the length of the cross-bracing section is adjusted according to the width of the tunnel excavation section.
3. The urban gate-type tunnel supporting structure according to claim 1, wherein the connection point of the cross-brace section steel and the steel arch is 5cm away from the steel arch bottom supporting point but not more than the tunnel pavement structure limit.
4. The urban gate-type tunnel supporting structure according to claim 3, wherein two ends of the cross-bracing section steel are connected with the bottom of the steel arch in a double-sided welding mode.
5. The urban gate-type tunnel supporting structure according to claim 1, wherein the primary spraying concrete layer, the anchor rods, the reinforcing mesh, the steel arch and the re-spraying concrete layer form the primary supporting structure.
6. The urban gate type tunnel supporting structure according to claim 5, wherein the installation time of the cross brace section steel is before final setting of the re-spraying concrete layer, and the cross brace section steel and the primary supporting structure are stressed synchronously.
7. The urban gate type tunnel supporting structure according to claim 1, wherein the bottom supporting points of the urban gate type steel arch frames are preset with welding positioning marks, and the ends of the cross-bracing type steel are welded after being positioned by the positioning marks.
8. The urban gate-type tunnel supporting structure according to claim 1, wherein reinforcing steel plates are arranged at the connection points of the transverse strut steel and the steel arches so as to improve the shear strength of the connection points.
9. The urban gate-type tunnel supporting structure according to claim 5, wherein the cross-bracing section steel is longitudinally arranged at intervals along the tunnel, and the interval is 50-80 cm.
10. The urban gate-type tunnel supporting structure according to claim 1, wherein the cross-sectional width of the cross-sectional steel is not less than 1/2 of the cross-sectional width of the urban gate-type steel arch.

Description

City door opening type tunnel supporting structure Technical Field The utility model relates to the technical field of tunnel construction, in particular to a gate-hole type tunnel supporting structure. Background The underground cavity excavation supporting is a common construction project in the field of construction engineering, and the conventional cavity structure generally has two structural types of horseshoe shape and urban gate hole type. Among them, the urban gate type section is widely used in tunnel design due to its elegant structure and wide space advantage. Most tunnel engineering has poor surrounding rock geological conditions at the inlet section or fault zone and other parts, is difficult to naturally form a hole, and needs to adopt a steel arch for primary support. When the rock mass lithology, the groundwater level and other conditions of the selected entrance opening on one side of the mountain or on two sides of the hole axis are inconsistent, the steel arch always bears uneven lateral pressure of the rock mass (soil mass) on two sides before the concrete is secondarily lined, and the arch is easy to deform or even topple to influence the safety of the grotto. Disclosure of utility model The utility model provides a gate-type tunnel supporting structure which is used for solving the defect of underground cavity excavation supporting in the prior art. The utility model provides an urban tunnel supporting structure, which is constructed on an excavation structure surface formed after tunnel excavation is completed, and comprises a primary spraying concrete layer, anchor rods, reinforcing steel meshes, a steel arch frame, a re-spraying concrete layer and transverse supporting steel, wherein the primary spraying concrete layer is positioned on the surface of the excavation structure surface, the early high-strength steel fiber concrete with the thickness of 3 cm to 5cm is sprayed on the surface of an excavation contour, the anchor rods are arranged around the excavation structure surface at certain intervals to enable the whole excavation structure surface to be stressed stably, the steel arch frame is positioned on the surface of the primary spraying concrete layer and is formed by vertically fixing the steel sections along the surface of the primary spraying concrete layer, the reinforcing steel meshes comprise two layers which are respectively arranged on two sides of the steel arch frame, one layer covers the surface of the primary spraying concrete layer, the other layer is positioned on the bottom surface of the re-spraying concrete layer, the re-spraying concrete layer is formed by spraying the early high-strength steel fiber concrete covering the outer layer, and the transverse supporting steel meshes and the bottom of the steel arch frame form horizontal symmetrical support. According to the urban gate type tunnel supporting structure provided by the utility model, the transverse strut steel comprises I-steel, H-steel or channel steel, and the length of the transverse strut steel is adjusted according to the width of the tunnel excavation section. According to the urban gate type tunnel supporting structure provided by the utility model, the connection point of the transverse strut section steel and the steel arch is 5cm away from the bottom supporting point of the steel arch, but does not exceed the limit of a tunnel pavement structure. According to the urban gate tunnel supporting structure provided by the utility model, two ends of the transverse strut steel are connected with the bottom of the steel arch in a double-sided welding mode. According to the urban gate type tunnel supporting structure provided by the utility model, the primary spraying concrete layer, the anchor rods, the reinforcing steel mesh, the steel arch and the re-spraying concrete layer form the primary supporting structure. According to the urban gate type tunnel supporting structure provided by the utility model, the installation time of the transverse strut section steel is before the final setting of the re-spraying concrete layer, and the transverse strut section steel and the primary supporting structure are stressed synchronously. According to the urban gate type tunnel supporting structure provided by the utility model, the bottom supporting point of the urban gate type steel arch frame is preset with the welding positioning mark, and the end part of the transverse strut type steel is welded after being positioned by the positioning mark. According to the urban gate type tunnel supporting structure provided by the utility model, the reinforced steel plate is arranged at the connection point of the transverse strut section steel and the steel arch frame so as to improve the shear strength of the connection point. According to the urban gate type tunnel supporting structure provided by the utility model, the cross bracing section steel is longitudinally arranged at intervals along the tunnel, and the i