CN-116771381-B - Reinforcing structure for corrosion tunnel lining and design method

CN116771381BCN 116771381 BCN116771381 BCN 116771381BCN-116771381-B

Abstract

The invention discloses a reinforcing structure for a corrosion tunnel lining and a design method thereof, wherein the reinforcing structure is arranged at a position to be reinforced of the lining, the reinforcing structure comprises a reinforcing member, a concrete layer connected with the reinforcing member and a connecting piece, the connecting piece is used for fixing the reinforcing member on the concrete layer or on the tunnel lining, and the reinforcing structure can be suitable for the working conditions that the lining concrete has lost structural strength and fiber materials or anchoring steel plates cannot be adhered to the surface of the lining with lost strength so as to adapt to reinforcing the tunnel in large-area corrosion. In the design method of the invention, when the reinforcement is selected in the next specification, the calculation amount of selecting the reinforcement with proper specification can be greatly reduced according to the judgment of the ascending order or the descending order of the specifications, and whether the reinforcement with larger specification is selected upwards or the reinforcement with smaller specification with higher economy is selected downwards is determined according to whether the requirement is met or not.

Inventors

LEI MINGFENG
DUAN LIAN
LI YONGHENG
WU JIANGHANG
ZHA XICAO
WANG LICHUAN
WU CHAOGUANG

Assignees

中南大学
中国铁路广州局集团有限公司

Dates

Publication Date: 20260505
Application Date: 20221114

Claims (3)

1. A method for designing a reinforcement structure for a corrosive tunnel lining, for realizing a reinforcement structure (1), characterized in that the method comprises the steps of: s1, investigation and sampling, and carrying out mechanical test on a corroded lining concrete sample to obtain related parameters; S2, building a load structure mode calculation model based on related parameters and calculating to obtain internal force values of each section of the lining; s3, determining the most unfavorable cross section of the original lining based on the internal force value of each cross section, and taking the stress state of the cross section as the design limit bearing capacity of the lining structure ; S4, selecting a reinforcement with proper specification for reinforcement, wherein the selection rule is as follows: S4.1, arbitrarily selecting a certain initial specification as a current specification; s4.2, respectively calculating the crack resistance bearing capacity of the reinforced lining structure of the reinforcement of the current specification And ultimate bearing capacity ; S4.3, selecting the reinforcement of the next specification according to the ascending or descending order of the specifications, and calculating the corresponding reinforcement of the next specification And ; Step S4.4, if the current specification corresponds to the next specification And When the requirement is met, selecting a reinforcement with a proper specification, otherwise, returning to the step S4.2 by taking the next specification as the current specification; The decision rule for whether the requirement is satisfied is as follows: when the reinforcement is selected according to the increasing order of the specifications, if the reinforcement meets the corresponding specification of the current specification And the next specification corresponds to When the reinforcement of the next specification is used as the reinforcement finally determined; When the reinforcement is selected according to the descending order of the specifications, if the current specification is met And the next specification corresponds to When the reinforcement is used, the reinforcement with the current specification is used as the reinforcement which is finally determined; in the step S1, the related parameters comprise the geometric dimension of the tunnel section, the corrosion depth of lining concrete, the thickness of the original lining design, the strength grade of the original lining concrete design, the level of surrounding rock of the tunnel and the physical and mechanical parameters of the surrounding rock; when the channel steel is selected as the reinforcement, in step S4.2 And As shown in formula 1) and formula 2): crack resistance load bearing capacity ; 1); Ultimate bearing capacity ; 2); Wherein, the The elastic modulus of the concrete is not corroded; is the ultimate tensile strain of the edge of the concrete on the tension side; Section thickness lining the tunnel; The height of the section compression area is the height of the section compression area when cracking; the longitudinal width lining the tunnel; Designing a value for the tensile strength of the newly poured concrete layer; is the elastic modulus of steel; the wing plate length of the channel steel; Is the cross-sectional area of the channel steel wing plate; is the cross-sectional area of the channel steel web; is the section eccentricity; the compressive strength design value of the non-corroded concrete; Compressive strain for the edge of the concrete on the compression side; When corrugated board is selected as reinforcement, in step S4.2 And As shown in formula 3) and formula 4): crack resistance load bearing capacity ; 3); Ultimate bearing capacity ; 4); Wherein, the The elastic modulus of the concrete is not corroded; is the ultimate tensile strain of the edge of the concrete on the tension side; Section thickness lining the tunnel; The height of the section compression area is the height of the section compression area when cracking; the longitudinal width lining the tunnel; Designing a value for the tensile strength of the newly poured concrete layer; is the elastic modulus of steel; Is the cross-sectional area of the corrugated plate; is the section eccentricity; the compressive strength design value of the non-corroded concrete; Compressive strain for the edge of the concrete on the compression side; in the step S4.3, the next-specification reinforcement is selected according to the specification increasing or decreasing order, and the judgment rule is as follows: first, the reinforcement of the current specification calculated in step S4.2 is obtained And ; A second step, according to the first step, corresponding to the reinforcement of the current specification Value of (2) and A comparison is made with respect to the number of the cells, If it is Selecting the reinforcement of the next specification according to the descending order of the specifications, otherwise, selecting the reinforcement of the next specification according to the ascending order of the specifications; The reinforced structure (1) is arranged at a position to be reinforced of a lining (2) in a tunnel, the reinforced structure (1) comprises a reinforcing member (1.1), a concrete layer (1.2) connected with the reinforcing member (1.1) and a connecting piece (1.3), and the connecting piece (1.3) is used for fixing the reinforcing member (1.1) on the concrete layer (1.2) or on the lining (2); The reinforcement (1.1) is arc-shaped channel steel (1.1 a), the connecting piece (1.3) is an expansion bolt (1.3 a), the channel steel (1.1 a) is arranged in the concrete layer (1.2), the web plate of the channel steel (1.1 a) is tightly attached to the position to be reinforced of the lining, the expansion bolt (1.3 a) is connected with the lining and the web plate of the channel steel (1.1 a), Or the reinforcing part (1.1) is an arc corrugated plate (1.1 b), the connecting part (1.3) is a rivet (1.3 b), the concrete layer (1.2) is clung to the position to be reinforced of the lining, the corrugated plate (1.1 b) is arranged on one side of the concrete layer (1.2) far away from the lining, and the corrugated plate (1.1 b) is fixed on the concrete layer (1.2) through the rivet (1.3 b); The concrete layer (1.2) is a micro-expansive concrete layer.
2. The method for designing a reinforcing structure according to claim 1, wherein in the step S1, lining concrete core samples are drilled in the corrosion area by a core drilling machine, and the sampling rule is as follows: When the area is corroded 1M 2 , drilling 1 core sample in the corrosion center; When 1m 2 < corrosion area 4M 2 , drilling 3 core samples in the corrosion center area, wherein the drilling interval is 1m; When the corrosion area is more than 4m 2 , 5 core samples are drilled in the corrosion center area, and the drilling interval is 1m.
3. The method according to claim 1 or 2, wherein before step S4, it is determined whether to select channel steel or corrugated board as the reinforcement, the selection rules are as follows: when the corrosion depth of the lining concrete is greater than or equal to 10cm, selecting channel steel as a reinforcing member; and when the corrosion depth of the lining concrete is less than 10cm, selecting the corrugated plate as a reinforcing member.

Description

Reinforcing structure for corrosion tunnel lining and design method Technical Field The invention relates to the field of tunnel structures, in particular to a reinforcing structure for a corrosion tunnel lining and a design method. Background The problems of leakage water, lining cracking, concrete corrosion and the like of the old tunnel are common under the actions of early construction quality, long-term environmental corrosion and dynamic load of a train, the normal operation of a line is seriously influenced, and particularly the corrosion problem of tunnel lining concrete is common under the influence of sulfate corrosive environment in western regions of China. Therefore, how to reinforce and repair the operation tunnels with the corrosion degradation becomes a great difficulty and urgent need in the field of tunnel engineering in China. Aiming at a plain concrete lining structure with large-area corrosion degradation, as the lining concrete has lost structural strength within a certain thickness range, fiber materials or anchoring steel plates and the like cannot be adhered to the lining surface with lost strength during actual repair, the next reinforcing construction can be carried out only after the severely corroded part is usually required to be chiseled, meanwhile, the mechanical conversion mechanism of the lining structure after reinforcing and repairing and the design are not quantized, the actual construction adopts an empirical judgment method to determine the repairing design scheme, and the reliability and economy of the design lack strict theoretical basis. In view of the foregoing, there is a need for a reinforcement structure and design method for corrosion tunnel lining to solve the problems of tunnel reinforcement and lack of quantization guidance in the prior art. Disclosure of Invention The invention aims to provide a reinforcement structure and a design method for a corrosion tunnel lining, which are used for solving the problems of tunnel reinforcement and lack of quantitative guidance in the prior art, and the concrete technical scheme is as follows: The reinforcing structure comprises a reinforcing member, a concrete layer and a connecting piece, wherein the concrete layer is connected with the reinforcing member, and the connecting piece is used for fixing the reinforcing member on the concrete layer or on the lining. The technical proposal is that the reinforcement is preferably arc-shaped channel steel, the connecting piece is an expansion bolt, the channel steel is arranged in the concrete layer, the web plate of the channel steel is clung to the position to be reinforced of the lining, the expansion bolt is connected with the lining and the web plate of the channel steel, Or the reinforcement is curved buckled plate, the connecting piece is the rivet, and concrete layer is hugged closely in the waiting of lining up and is consolidated the position, and the buckled plate sets up in concrete layer one side of keeping away from the lining up, and the buckled plate passes through rivet fastening on concrete layer. Preferably, the concrete layer is a micro-expansion concrete layer. The design method of the reinforcement structure for the corrosion tunnel lining is used for realizing the reinforcement structure and comprises the following steps: s1, investigation and sampling, and carrying out mechanical test on a corroded lining concrete sample to obtain related parameters; S2, building a load structure mode calculation model based on related parameters and calculating to obtain internal force values of each section of the lining; S3, determining the least favorable section of the original lining based on the internal force value of each section, and taking the stress state of the section as the design limit bearing capacity N 0 of the lining structure; s4, selecting a reinforcement with proper specification for reinforcement, wherein the selection rule is as follows: S4.1, arbitrarily selecting a certain initial specification as a current specification; S4.2, respectively calculating the crack resistance bearing capacity N cr and the ultimate bearing capacity N cu of the reinforced lining structure of the reinforcement with the current specification; S4.3, selecting a reinforcement of the next specification according to the ascending or descending order of the specifications, and calculating N cr and N cu corresponding to the next specification; Step S4.4, selecting a reinforcement with a proper specification if N cr and N cu corresponding to the current specification and the next specification meet the requirements, otherwise, returning to the step S4.2 by taking the next specification as the current specification; The decision rule for whether the requirement is satisfied is as follows: when the reinforcement is selected according to the increasing order of the specifications, if the min { N cr,Ncu}＜N0 corresponding to the current specification is met and the min { N cr,Nc