Patent Application
20230313681
This application claims the priority benefit of China application serial no. 202210326219.5, filed on Mar. 29, 2022. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.
The present invention relates to the field of tunnel shield materials, in particular to an intelligent segment with concrete embedded with gas/liquid-filled steel pipes.
The shield technology is widely applied to underground traffic engineering, and shield linings often need to bear relatively high water and soil pressure and have relatively high requirements for impermeability. At present, especially for river bottom tunnels and deep-buried tunnels, the conventional shield lining forms can hardly meet the requirements of the engineering for both mechanical performances and working performances of structures, and methods such as large-area reinforcing ribs and secondary linings are required to improve the structure strength and reduce cracks; however, by means of such methods, the dead weight of the structures is increased, the construction processes are more complex, and the construction costs are increased to a certain extent.
The present invention aims to provide an intelligent segment with concrete embedded with gas/liquid-filled steel pipes so as to overcome the defects in the prior art.
The purpose of the present invention can be achieved through the following technical solution:
The plurality of steel pipes are arranged, and rib marks are formed on the surfaces thereof and are used to meet the anchoring requirements between the steel pipes and the concrete.
Gas/liquid filling valves are arranged in steel pipe spans and are used to ensure uniform distribution of the initial stress in the steel pipes, the pneumatic/hydraulic control system comprises pneumatic/hydraulic monitoring devices and pressure stabilizing devices arranged at two ends of the steel pipes, the pneumatic/hydraulic monitoring devices are used to monitor the internal pressure of the gas/liquid-filled steel pipes in real time, when the internal pressure exceeds the preset internal pressure, gas/liquids in the steel pipes are released by means of the pressure stabilizing devices to maintain the pneumatic/hydraulic balance in the pipes, and the overall stress and deformation conditions of a tunnel structure are fed back according to the change of the gas/liquid pressure in the steel pipes.
The steel pipes are filled with phase-change materials which are used to adjust the temperature and prevent freezing in a tunnel.
The steel pipes are internally provided with support members for enhancing the rigidity of the steel pipes, and the support members are made of materials such as alloy steel, high polymers or high-polymer capsules.
The steel pipes are filled with the incomplete liquid which is used to absorb shocks and improve the shock resistance.
A shape memory alloy net is arranged on an inner surface of the intelligent segment, and deformation of shape memory alloys in different regions is controlled by means of electrified heating excitation so as to adjust the local mechanical performance of the segment.
Circumferential seams of the intelligent segment are connected by inserting the inclined bolts into the circumferential seam hand holes, the circumferential seam hand holes are uniformly formed in two sides of the circumferential seams in a staggered manner, and concave and convex mortises are uniformly formed at circumferential joints of the segment so as to facilitate construction, installation and positioning.
Longitudinal seams of the intelligent segment are connected to a circumferentially adjacent segment by matching the steel plate connectors and/or hand hole embedded members with the straight bolts installed in the longitudinal seam hand holes.
Each of the steel plate connectors is a complete straight steel plate, the straight steel plates of two circumferentially adjacent segments are fixedly connected by means of the straight bolts installed in the longitudinal seam hand holes, and two ends of the steel pipes in the segments are integrally welded to the steel plate connectors respectively; and
Compared with the prior art, the present invention has the following advantages:
The present invention is described in detail in conjunction with the accompanying drawings and particular embodiments below.
The present invention provides an intelligent segment with concrete embedded with gas/liquid-filled steel pipes, which is described in detail below.
The segment of the present invention structurally comprises a concrete portion 1, a steel pipe portion, a reinforcing bar portion, a joint portion and a controllable deformation material portion, wherein the concrete portion 1 is made of common, high-strength or ultra-high performance concrete; the steel pipe portion is made of a 20CrMo material and comprises a gas/liquid filling system and a pneumatic/hydraulic control system; the reinforcing bar portion is made of reinforcing bars in the model of HRB400; the joint portion comprises circumferential seam joints 14 and longitudinal seam joints 15, each of the circumferential seam joints 14 comprises a circumferential seam hand hole 7 and a high-strength inclined bolt, and each of the longitudinal seam joints 15 comprises a Q345 steel plate connector 5 and a high-strength straight bolt; and the controllable deformation material portion is a shape memory alloy net, is made of an NiTi alloy, is installed on a surface as shown in
For the steel pipe design, the mechanical requirements of the structure should be considered firstly, and then the structure requirements of the structure should be considered. According to the stress conditions of the structure, the gas/liquid-filled steel pipes 13 should be uniformly arranged on the tension side, and it can be known from experiments that the rigidity of the segment is positively related to the number, the diameter, the internal pressure and the thickness of the steel pipes and the dead weight of the segment is negatively related to the number and the diameter of the steel pipes. Attention should be paid to the local stress safety of the concrete around the steel pipes during the steel pipe design. According to the structure requirements of the structure, the steel pipes penetrate through the whole segment in the circumferential direction, and collisions with the circumferential seam joints 14 need to be avoided. Rib marks are designed on outer surfaces of the steel pipes so as to meet the anchoring requirements between the steel pipes and the concrete.
The gas/liquid filling valves 12 are arranged in the steel pipe spans, which is beneficial to uniform distribution of the initial stress in the steel pipes. The pneumatic/hydraulic control system is arranged at the two ends of the steel pipes and comprises the pneumatic/hydraulic monitoring devices and the pressure stabilizing devices 11. The pneumatic/hydraulic monitoring devices can monitor the internal gas pressure of the gas/liquid-filled steel pipes 13 in real time, which facilitates safety evaluation. Once the gas/liquid pressure exceeds the preset internal pressure, the pressure stabilizing devices 11 can release the gas/liquids to maintain the pneumatic/hydraulic balance in the pipes.
The steel pipes can be filled with the gas or liquids and can also be filled with phase-change materials which are used to adjust the temperature and prevent freezing in a tunnel.
Support members can be properly arranged in the steel pipes to improve the rigidity of the steel pipes, can be made of alloy steel as well as high polymers or high-polymer capsules, and have the better working performances under the equivalent mechanical performance conditions.
According to the need for shock resistance, the steel pipes can be filled with a certain amount of liquid (not full) which is used to absorb shocks and improve the shock resistance.
The pneumatic/hydraulic monitoring devices on the steel pipes can feed back the overall stress and deformation conditions of a tunnel structure according to the change of the gas/liquid pressure in the steel pipes.
The steel pipes of various segments can be connected by means of pipelines to realize distribution of the gas/liquid among the different segments, and can also be supplemented with pressure from the outside to realize automatic adjustment of the overall rigidity, deformation and stress of the tunnel structure.
According to disaster warnings such as earthquake warnings, the pressure in each steel pipe of the segment can be adjusted in advance to change the stress state of a whole-ring structure, thereby improving the disaster resistance when disasters come.
Novel segment joint designs are divided into the longitudinal seam joints 15 and the circumferential seam joints 14. The circumferential seams are connected by inserting the inclined bolts into the hand holes, and the circumferential seam hand holes 7 are uniformly formed in two sides of the circumferential seams in a staggered manner. The steel plate connectors 5 are arranged at the longitudinal seams, the steel plate connectors 5 and the gas/liquid-filled steel pipes 13 in the segment are integrally welded, and the straight bolts are installed in the longitudinal seam hand holes 2 to be connected to the circumferentially adjacent segment. The circumferential stress at the longitudinal seams can be diffused to the whole segment by means of the gas/liquid-filled steel pipes 13, which is beneficial to reduction of the stress concentration effect at the joints of the segment.
The concave and convex mortises are uniformly formed at the circumferential joints of the segment so as to facilitate construction, installation and positioning. The seams of the segment are subjected to the seam water stop design according to standards so as to improve the impermeability of the structure.
The controllable deformation material portion is a shape memory alloy net made of the NiTi alloy and is installed on the inner surface of the segment by means of the reliable adhesive, the shape memory alloy net is communicated with a circuit, and shape memory alloys in different regions can be heated by means of the current so as to control local deformation of the segment and adjust the local stress of the concrete.
Taking a shield tunnel across the Yangtze River as an example, a segment of the tunnel has an inner diameter of 14.1 m, an outer diameter of 15.4 m, a wall thickness of 650 mm and a ring width of 2 m. The form of a composite segment with ultra-high performance concrete embedded with gas-filled steel pipes is adopted, four hollow steel pipes having the thickness of 8 mm are arranged in the segment, wherein the two steel pipes in the middle have the diameter of 200 mm and the circle center distance of 360 mm, the two steel pipes on the outer side have the diameter of 100 mm and the circle center distance of 1560 mm, and high-pressure gas under 3 MPa is introduced into all the steel pipes.
According to numerical simulation of finite element software, compared with existing concrete shield segments, the composite segment with the ultra-high performance concrete embedded with the gas-filled steel pipes has the advantages that the dead weight is reduced by about 10%, and the rigidity is improved by about 30%, thereby effectively improving the stress performance of the segment in the shield tunnel. Steel plate connectors are used at circumferential joints of the segment and are welded to the gas-filled steel pipes, so that the stress of bolts at the junctions can be reduced, meanwhile, the stress at the junctions is diffused by means of the steel pipes to the steel plates and the concrete in contact with the steel pipes to be borne jointly, and the condition of stress concentration at the joints is greatly improved.
According to engineering geological investigations, typical sections DK14 and DK211 are selected, the structural design is finally completed by calculating loads and analyzing internal forces, and the results are as shown in Table 2.
The DK14 segment section is as shown in
In conclusion, in order to meet the structure requirements of river bottom tunnels or deep-buried tunnels for shield linings, an ultra-high performance concrete material is used, the intelligent segment with the concrete embedded with the gas/liquid-filled steel pipes is designed, the segment improves the rigidity and the strength of the structure, greatly reduces reinforcing bars required by the segment and effectively reduces the stress concentration effect at the joints while effectively reducing the dead weight of the structure, and the working performances such as the durability, the impermeability and the shock resistance are superior to those of conventional segments. In addition, the segment also conforms to the development trend of prefabricated structures of underground tunnels, can greatly reduce the use amount of the concrete, and can meet the requirements of the national low-carbon strategy.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202210326219.5 | Mar 2022 | CN | national |
