Flexible pipe section suitable for use at a fracture zone and a simulation test device and a test method thereof

Abstract

The application provides a flexible pipe piece suitable for a fracture zone, a simulation experiment device and an experiment method, the flexible pipe piece comprising an arc-shaped pipe piece body, a shear joint being arranged in the middle of the pipe piece body, a shear type force sensor being arranged at the shear joint, and the pipe piece bodies on opposite sides in the shear joint being connected through elastic members; a steel plate member and a water-swelling waterstop being embedded in the pipe piece body; bolt holes for connecting with adjacent pipe piece bodies being arranged on the upper and lower sides of the pipe piece body; the steel plate member comprising fixed steel plates arranged on the upper and lower sides, movable steel plates being arranged on the left and right sides of the steel plate member, and the pipe piece body and the movable steel plates being connected through double-acting jacks. The technical scheme of the application improves the flexibility of the whole structure, has higher safety, and can effectively reduce the influence of the fault zone dislocation on the tunnel structure under the action of the earthquake.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of tunnel engineering, and in particular to a ductile segment suitable for a fracture zone and a simulation experiment device and experiment method thereof. BACKGROUND

[0002] In actual engineering, subway shield tunnels inevitably pass through some adverse geological zones, such as water-rich sand layers and fracture zones. With the continuous development of rail transit and underground space, in order to meet the demand for transportation, many tunnels under construction or to be constructed inevitably need to pass through fracture zones. However, under the action of an earthquake, a fracture zone will produce a large shear force and displacement dislocation, which may cause the shield segment joint to open, thereby causing structural leakage and local damage to the concrete. Therefore, in terms of mitigating the effects of an earthquake, some technologies have studied the internal structure of a shield tunnel segment and designed a segment suitable for passing through an active fault. Since a fracture zone not only dislocates under an earthquake, but also accumulates strain energy through continuous slow creep, it suddenly dislocates after reaching a limit. Some researchers have studied the peripheral maintenance structure of a segment to alleviate the deformation of the segment caused by the creep dislocation of a fracture zone. Meanwhile, a model experiment has been used to simulate the influence of the creep dislocation of a fracture zone on a tunnel structure.

[0003] Since the construction of a shield tunnel is relatively costly, the assembly technology of the segment is relatively high. The existing research cannot clearly determine the position of the tunnel damage at the fracture zone. The segment studied by some technologies is relatively complex to assemble and install, which increases the construction difficulty and inevitably ensures the quality of the construction. The peripheral maintenance structure of the segment increases the construction process and makes the construction more difficult, thereby greatly increasing the manufacturing cost. Meanwhile, the model experiment only studies the influence of the creep dislocation on the tunnel lining structure, and does not study the influence of the sudden dislocation of a fracture zone on a tunnel structure under the action of an earthquake.

[0004] In view of the problems in the related art, no effective solution has been proposed so far, and therefore, there is an urgent need to propose a new intelligent ductile segment suitable for a fracture zone and a model experiment device and method thereof. SUMMARY

[0005] In view of the above technical problems, the present application discloses a ductile segment suitable for a fracture zone and a simulation experiment device and experiment method thereof. The new ductile segment embeds a steel plate in the segment, mainly utilizes the plasticity and high toughness of the steel plate, and reduces the damage to the shield tunnel segment when the fracture zone seriously dislocates.

[0006] To this end, the technical scheme adopted by the present application is as follows:

[0007] The application discloses a flexible pipe segment suitable for a fracture zone, which comprises an arc-shaped pipe segment body, a shear joint is arranged in the middle of the pipe segment body, a shear force sensor is arranged at the shear joint, and the pipe segment bodies on the opposite sides of the shear joint are connected through elastic members; a steel plate member and a water-swelling sealing strip are embedded in the pipe segment body, and the water-swelling sealing strip is arranged between the steel plate member and the pipe segment body; bolt holes for connecting with adjacent pipe segment bodies are arranged on the upper and lower sides of the pipe segment body.

[0008] The steel plate member comprises fixed steel plates arranged on the upper and lower sides, and movable steel plates arranged on the left and right sides of the steel plate member, and the pipe segment body and the movable steel plates are connected through double-acting jacks.

[0009] The steel plate member is arranged between the two bolt holes, and the shear joint is filled with concrete.

[0010] In the technical scheme, the steel plate member is embedded in the flexible pipe segment body, the flexibility of the whole structure is improved, the structure has higher safety reserve, the serious damage of the shield tunnel pipe segment at weak positions caused by the serious dislocation of the fracture zone is prevented, and the tunnel can normally operate after repair. Meanwhile, the shear joint is arranged in the flexible pipe segment body, the shear force sensor is arranged at the shear joint, the shear force sensor can be used for positioning the damage position and transmitting the earthquake signal, the signal transmitted by the shear force sensor can be used for starting the double-acting jacks to move the left and right movable steel plates to the left and right directions respectively, the weak position is formed in the pipe segment, the tunnel is guided to be damaged, the damage of the pipe segment at the joint is avoided, and the leakage in the tunnel is avoided.

[0011] In addition, the pipe segment body and the shear joint concrete of the flexible pipe segment are connected through the elastic members, so that the pipe segment body and the shear joint concrete have certain integrity. When the fracture zone is dislocated, the elastic members can be sheared and deformed under the shearing force, so that the integrity of the structure is ensured and the structure has certain freedom.

[0012] As a further improvement of the application, the fixed steel plates and the movable steel plates are low-carbon steel plates.

[0013] As a further improvement of the application, the elastic members are alloy springs.

[0014] As a further improvement of the application, the pipe segment body is provided with a reserved hole outside the movable steel plate, the double-acting jack is arranged in the reserved hole, one end of the double-acting jack is connected with the pipe segment body, and the other end of the double-acting jack is connected with the movable steel plate through a connecting member.

[0015] As a further improvement of the present application, the connecting member is a steel strand.

[0016] As a further improvement of the present application, the upper and lower sides of the segment body are provided with grooves for setting the expansion waterstop.

[0017] As a further improvement of the present application, the segment bodies are connected to form segment rings, the adjacent segment bodies are connected by bolts, and the adjacent segment rings are connected by bolts.

[0018] As a further improvement of the present application, the joint between the adjacent segment bodies is provided with a water-expanding waterstop, and the joint between the adjacent segment rings is provided with a connecting steel plate, and the connecting steel plate is provided with a water-expanding waterstop between the connecting steel plate and the concrete of the segment ring. With the technical scheme, the water-expanding waterstop is used at the joint between the segment and the segment, and the steel plate is used at the joint between the segment ring and the segment ring, and the steel plate and the waterstop both have excellent toughness, which can effectively avoid the damage of the waterproof material due to the excessive deformation of the segment, and further cause the leakage of the tunnel.

[0019] As a further improvement of the present application, the thickness of the connecting steel plate is 1.5 cm, and the width is 25 cm.

[0020] As a further improvement of the present application, the connecting steel plate is a low-carbon steel plate.

[0021] As a further improvement of the present application, the ductile segment suitable for the fracture zone comprises ordinary segments at both ends, the ordinary segments are connected with the segment ring by bolts, the ordinary segments are embedded in the soil, and the ductile segment is located at the fracture surface.

[0022] The application further discloses a simulation experiment device of the novel intelligent ductile segment suitable for a fracture zone, and the simulation experiment device comprises a base, a counterforce frame is arranged on the base, a hydraulic loading mechanism is arranged on the top of the counterforce frame, a lower plate of a fault and an upper plate of the fault are arranged on the base, and the hydraulic loading mechanism faces the lower plate of the fault and the upper plate of the fault.

[0023] The lower wall of the fault plane comprises a lower wall base plate, two lower wall side plates, a lower wall front plate and a top plate; the upper wall of the fault plane comprises an upper wall base plate, two upper wall side plates, an upper wall front plate and a top plate; the middle part of the upper wall front plate and the lower wall front plate is provided with an opening with the same size as the outer diameter of the pipe segment to be tested, for the pipe segment to pass through; the lower wall base plate is fixedly connected to the base plate through a fixing member, and the upper wall base plate is connected to the base plate through an upper wall jack; the pipe segment tunnel to be tested is located in the upper wall and the lower wall, and the ordinary pipe segments at the two ends are sealingly connected to the upper wall front plate and the lower wall front plate respectively; a fracture surface simulation steel plate is arranged between the lower wall and the upper wall, the middle part of the fracture surface simulation steel plate is provided with a hole with the same size as the outer diameter of the pipe segment tunnel, and the fracture surface simulation steel plate is connected to the lower wall and the upper wall respectively; the counterforce frame is provided with a hook above the upper wall.

[0024] As a further improvement of the application, the counterforce frame is inverted U-shaped, the two lower wall side plates are connected to the lower wall base plate through screws or buckles respectively, and the two upper wall side plates are connected to the upper wall base plate through screws or buckles respectively.

[0025] The application further discloses an experimental method of the simulation experiment device for the ductile pipe segment at the fracture zone as described above, which comprises the following steps:

[0026] Step S1, install the simulation experiment device for the ductile pipe segment at the fracture zone, fix the simulation experiment device for the ductile pipe segment at the fracture zone on the ground, and fix the upper wall jack and the fixing member on the base through bolts; lay the first layer of soil, the height of the soil is flush with the bottom of the middle opening of the lower wall front plate and the upper wall front plate, and the soil is compacted after being laid;

[0027] Step S2, install the first pipe segment ring of the pipe segment tunnel to be tested on the upper cover front plate through bolts and sealing pads, paste strain gauges on the shear joints of the pipe segment body, sequentially splice the next pipe segment ring and strain gauges, and repeat the above operation until all the pipe segments for testing are spliced; the last pipe segment ring is installed on the lower cover front plate through bolts and sealing pads;

[0028] Step S3, reinforce the pipe segment body through high-strength bolts near the fracture surface, and set water-swelling waterstop at the joints of adjacent pipe segment bodies and steel plates at the joints of adjacent pipe segment rings;

[0029] Step S4, after splicing, continue to lay the soil layer and compact the soil to ensure that the soil is in a dense state;

[0030] Step S5, aligning and installing the bottom plate of the lower plate of the fault with the side plate of the lower plate of the fault and the front plate of the lower plate of the fault through bolts or buckles, and aligning and installing the top plate of the upper plate of the fault with the side plate of the upper plate of the fault and the front plate of the upper plate of the fault through bolts or buckles;

[0031] Step S6, performing a simulated stratum creep displacement experiment or a simulated fault zone sudden dislocation experiment under the action of an earthquake;

[0032] The simulated stratum creep displacement experiment comprises the following steps:

[0033] Step S11, ensuring that the upper plate jack of the fault is in a working state, and making the inclination angle of the upper plate jack of the fault the same as the inclination angle of the simulated steel plate of the fault surface, and the top of the upper plate jack of the fault being in contact with the bottom plate of the upper plate of the fault;

[0034] Step S12, starting the hydraulic loading device to apply a downward force to the upper plate of the fault, and simultaneously unloading the bottom upper plate jack of the fault to make the upper plate of the fault move stably; during the experiment, ensuring that the lower plate of the fault is in a fixed state;

[0035] Step S13, after the displacement of the upper plate of the fault reaches the set value of the experiment, stopping the hydraulic loading mechanism; recording the strain and local deformation of the ductile pipe and the damage of other positions during the experiment;

[0036] The simulated fault zone sudden dislocation experiment under the action of an earthquake comprises the following steps:

[0037] Step S21, ensuring that the upper plate jack of the fault is in a working state, and making the inclination angle of the upper plate jack of the fault the same as the inclination angle of the simulated steel plate of the fault surface, and the top of the upper plate jack of the fault being in contact with the bottom plate of the upper plate of the fault;

[0038] Step S22, fixing the upper plate of the fault and the hook located thereon through a rope;

[0039] Step S23, removing the upper plate jack of the fault at the bottom of the upper plate of the fault to make the upper plate of the fault in a suspended state;

[0040] Step S24, placing a buffer pad at the bottom of the upper plate of the fault; during the experiment, ensuring that the lower plate of the fault is in a fixed state;

[0041] Step S25, removing or cutting the rope of the upper plate of the fault to make it freely fall; recording the strain and local deformation of the ductile pipe and the damage of other positions during the experiment.

[0042] The step S1 of installing the simulation experiment device suitable for the ductile segment at the fracture zone comprises: aligning and installing the upper plate side of the fault and the upper plate bottom of the fault by bolts or buckles, aligning and installing the lower plate side of the fault and the lower plate bottom of the fault by bolts or buckles, and opening holes in the upper plate front of the fault and the lower plate front of the fault according to the test size of the segment; the fracture surface simulation steel plate is installed by bolts or buckles according to the design angle and the upper plate side of the fault, the lower plate side of the fault, the upper plate bottom of the fault and the lower plate bottom of the fault; and the sealing of the joint is ensured during the whole process.

[0043] Through the model experiment, the stress state and deformation of the ductile segment at the fracture zone under the action of the earthquake and creep can be studied, thereby providing certain reference value for actual engineering.

[0044] Compared with the prior art, the beneficial effects of the present application are:

[0045] Firstly, the ductile segment of the technical scheme is embedded with a steel plate inside the segment, the overall toughness of the structure is improved, the structure obtains higher safety reserve, the influence of the dislocation of the fracture zone under the action of the earthquake on the tunnel structure can be effectively reduced, and the tunnel can continue to operate after the tunnel is repaired in the later period; the shear joint is provided with a shear type force sensor, the shear type force sensor plays a role of positioning the damage position and transmitting the earthquake signal, and the position where the tunnel is about to be damaged can be determined through the sensor; after the receiver receives the signal transmitted by the sensor, the double-acting jack is started to move the movable steel plates on the left and right sides to the left and right directions respectively, so that a weak position appears in the segment, the tunnel is guided to be damaged, the damage of the segment at the joint is avoided, and the leakage phenomenon in the tunnel is avoided.

[0046] Secondly, the main body of the ductile segment and the shear joint concrete are connected through the elastic member, so that the two have certain integrity. When the fracture zone is dislocated, the elastic member can be sheared and deformed under the action of the shearing force, so that the integrity is ensured and a certain degree of freedom is also obtained. The steel plate member is arranged between the two bolt holes of the main body of the ductile segment, the ductile segment is assembled in the same way as the ordinary segment, that is, through the bolt connection, the ductility and the anti-seismic performance of the segment can be improved, and the normal assembly of the segment is not affected, thereby solving the complex construction problem in the prior art.

[0047] Thirdly, the model experiment is carried out by using the simulation experiment device and the experimental method, the influence of the different movement modes of the fracture zone on the stress state and deformation of the new ductile segment under the action of the earthquake and creep can be studied, the ductile segment can be optimized and improved in time, and the engineering can also be provided with reference. BRIEF DESCRIPTION OF DRAWINGS

[0048] Figure 1is a perspective view of the segment body of the present application, embodiment 1.

[0049] Figure 2 is a partial structural view of the segment body of the present application, embodiment 1.

[0050] Figure 3 is a cross-sectional view of the segment body of the present application, embodiment 1, i.e. a cross-sectional view along the longitudinal direction of the tunnel.

[0051] Figure 4 is a partial view of the segment body joint of the present application, embodiment 1.

[0052] Figure 5 is a partial view of the segment body joint of the present application, embodiment 1.

[0053] Figure 6 is a perspective view of the simulation experimental device of the present application, embodiment 2.

[0054] Figure 7 is a cross-sectional view of the simulation experimental device of the present application, embodiment 2.

[0055] The reference signs include:

[0056] 1, segment body; 2, shear joint; 3, bolt hole; 4, steel plate member; 5, ordinary segment; 6, soil layer; 7, fracture surface simulation steel plate; 8, alloy spring; 9, water-swelling sealing strip; 10, bolt; 11, connecting steel plate; 12, reserved hole; 13, shear type force sensor; 14, steel strand; 15, double-acting jack;

[0057] 21, base; 22, counter-force frame; 23, hydraulic loading mechanism; 24, upper fault plate jack; 25, lower fault plate fixing member; 26, iron hook; 27, sealing gasket; 28-1, upper fault plate top plate; 28-3, upper fault plate side plate; 28-4, upper fault plate bottom plate; 29-1, lower fault plate top plate; 29-2, lower fault plate front plate; 29-3, lower fault plate side plate; 29-4, lower fault plate bottom plate, 30-steel plate. DETAILED DESCRIPTION

[0058] The preferred embodiments of the present application are described in further detail below.

[0059] Embodiment 1

[0060] As Figures 1-5As shown, a ductile pipe segment suitable for a fracture zone includes an arc-shaped pipe segment body 1, a concrete-filled shear joint 2 is arranged in the middle of the pipe segment body 1, a shear force sensor 13 is arranged at the shear joint 2, and alloy springs 8 are arranged between the pipe segment bodies 1 on opposite sides in the shear joint 2; a steel plate component 4 and a water-swelling sealing strip 9 are embedded in the pipe segment body 1, and the water-swelling sealing strip 9 is arranged between the steel plate component 4 and the pipe segment body 1; bolt holes 3 for connecting adjacent pipe segment bodies 1 are arranged on the upper and lower sides of the pipe segment body 1; and the shear joint 2 and the steel plate component 4 are arranged between the two bolt holes 3.

[0061] The steel plate component 4 includes fixed steel plates arranged on the upper and lower sides and connected with the concrete of the pipe segment body 1, and movable steel plates arranged on the left and right sides and movable leftward and rightward, and the pipe segment body 1 and the movable steel plates are connected through double-acting jacks 15. The fixed steel plates and the movable steel plates are low-carbon steel plates. The pipe segment body 1 is provided with a reserved hole 12 on the outer side of the movable steel plate, the double-acting jack 15 is arranged in the reserved hole 12, one end of the double-acting jack 15 is connected with the pipe segment body 1, and the other end is connected with the movable steel plate through a steel strand 14. The double-acting jack 15 is started to work through information of the shear force sensor 13.

[0062] The steel plate component 4 is provided with ribs on the two sides and can be fully and effectively connected with the pipe segment body 1.

[0063] The pipe segment bodies 1 are connected through bolts 10 to form a pipe segment ring, and the water-swelling sealing strip 9 is arranged in the joint. Adjacent pipe segment rings are connected through bolts 10, and a connecting steel plate 11 is arranged between adjacent pipe segment rings, and the water-swelling sealing strip 9 is arranged between the connecting steel plate 11 and the concrete of the pipe segment ring. The connecting steel plate 11 is a low-carbon steel plate. The thickness of the connecting steel plate 11 is 1.5 cm, and the width is 25 cm.

[0064] The ductile pipe segment includes ordinary pipe segments 5 arranged at the two ends, the ordinary pipe segments 5 are connected with the pipe segment ring through bolts 10, the ordinary pipe segments 5 are embedded in the soil 6, and the ductile pipe segment is arranged at the fracture surface.

[0065] The working mechanism is as follows:

[0066] 1. The shear joint is arranged to guide the position of tunnel failure.

[0067] 2. The shear force sensor is arranged at the shear joint, and the position of tunnel failure can be determined through the sensor.

[0068] 3. When the value transmitted by the sensor reaches a certain limit, the double-acting jack starts to work, moving the left and right moving steel plates to the left and right respectively, causing a weak point to appear inside the tunnel segment, thus guiding the tunnel to be destroyed.

[0069] 4. By utilizing the high plasticity and toughness of low-carbon steel plates, the overall damage to shield tunnel segments is reduced when severe displacement occurs in the fracture zone, ensuring normal operation after subsequent repairs.

[0070] Example 2

[0071] like Figure 6 and Figure 7 As shown, a simulation experimental device for tough segments at fracture zones, as described in Example 1, mainly consists of a base 21, a reaction frame 22, a hydraulic loading mechanism 23, a fault upper plate jack 24, a fault lower plate fixing mechanism, an iron hook 26, a fault upper plate, a fault lower plate, and a fracture surface simulation steel plate 7. The fault lower plate and the fault upper plate are located on the base 21. The fault upper plate includes a fault upper plate top plate 28-1, a fault upper plate front plate (not shown in the figure), a fault upper plate side plate 28-3, and a fault upper plate bottom plate 28-4. The fault lower plate includes a fault lower plate top plate 29-1, a fault lower plate front plate 29-2, a fault lower plate side plate 29-3, and a fault lower plate bottom plate 29-4.

[0072] The hydraulic loading mechanism 23 is fixed to the top of the reaction frame 22 and faces the upper plate of the fault. A steel plate 30 is provided at the front end of the hydraulic loading mechanism 23 to apply pressure to the upper plate of the fault. The reaction frame 22 is a U-shaped reaction frame. The side plates 28-3 and 29-3 of the upper and lower plates of the fault are directly connected to the bottom plates 28-4 and 29-4 of the upper and lower plates of the fault, respectively, via screws or clips. The front plates 29-2 of the upper and lower plates of the fault are connected to the ordinary segments of the first and last rings, respectively, via fixing bolts. The first and last ordinary segments are sealed to the front plates 29-2 of the upper and lower plates of the fault using sealing gaskets 27 to ensure the airtightness of the experiment.

[0073] The fracture surface is simulated using a fracture surface simulation steel plate 7. The steel plate 7 is arranged according to the actual engineering fracture surface inclination angle, such as 75° in this embodiment (this can be modified according to experimental requirements). A hole is drilled in the middle of the steel plate, the size of which is consistent with the cross-sectional size of the tunnel passing through the steel plate. The fracture surface simulation steel plate 7 is connected to the upper and lower plates of the fault via bolts. The upper plate jack 24 and the lower plate fixing mechanism are connected to the base 21 via bolts. Iron hooks 26 are welded and fixed to the reaction frame 22.

[0074] The installation steps for this simulation experimental device are as follows:

[0075] 1. Align and install the fault upper plate side plate 28-3, fault lower plate side plate 29-3, fault upper plate bottom plate 28-4, and fault lower plate bottom plate 29-4 with bolts or clips. According to the tunnel test dimensions of the segment assembly, make holes in the fault upper plate front plate and fault lower plate front plate 29-2. Align and install the fracture surface simulation steel plate 7 with the fault upper plate side plate 28-3, fault lower plate side plate 29-3, fault upper plate bottom plate 28-4, and fault lower plate bottom plate 29-4 with bolts or clips according to the design angle. Ensure the sealing of the joints throughout the process.

[0076] 2. Fix the experimental device base 21 to the ground, and fix the upper fault plate jack 24 and the lower fault plate fixing component 25 to the corresponding positions on the base 21 with bolts.

[0077] 3. Fix the fault upper plate and fault lower plate assembled in step 1 to the fault upper plate jack 24 and fault lower plate fixing component 25 respectively according to their corresponding positions.

[0078] 4. Lay the first layer of soil. The type of soil should be selected according to the actual project. The height of the soil should be level with the bottom of the opening in front of the fault. After laying the soil, compact it. During the laying and compaction process, check the device for any leakage.

[0079] 5. Install the first ring segment onto the front plate of the fault upper plate using bolts and sealing gasket 27, ensuring the device is airtight. Attach strain gauges to the shear joints of the ductile segment body. After completion, sequentially assemble the next ring segment structure and strain gauges, repeating the above operation until all segment structures used for the test are assembled. The last ring segment structure is installed onto the front plate 29-2 of the fault lower plate using bolts and sealing gasket 27.

[0080] 6. Near the fracture surface, the segment installation type is flexible segments. The segments are reinforced with high-strength bolts to prevent damage to the connection from the area affected by the fracture surface. Water-swellable sealing strips are installed at the joints between flexible segments. Water-swellable sealing strips and low-carbon steel plates are installed at the joints between segment rings.

[0081] 7. After splicing the segments, continue to lay soil layers 6 in stages. The number of times the soil is laid depends on the properties of the soil. After each layer of soil is laid, it must be compacted to ensure that the soil is in a dense state.

[0082] 8. After the soil is laid in step 7 above, the upper plate 28-1 and the lower plate 29-1 of the fault are installed in alignment with the other plates using bolts or clips.

[0083] 9. After verifying that the above model device is installed correctly, the following experimental operations can be carried out.

[0084] The model experiment implementation method is as follows:

[0085] A: simulate the influence of stratum creep displacement on the stress state and deformation of ductile pipe piece.

[0086] 1. Before the experiment starts, ensure that the fault upper disc jack is in working condition, the inclination angle of the fault upper disc jack is consistent with the angle of the fracture surface simulation steel plate, and the top of the fault upper disc jack is in contact with the fault upper disc bottom plate.

[0087] 2. Start the hydraulic loading mechanism to apply downward force to the fault upper disc. While the fault upper disc moves downward, the bottom fault upper disc jack also unloads at the same time to ensure the stable movement of the fault upper disc.

[0088] 3. After the displacement of the fault upper disc reaches the experimental set value, the hydraulic loading mechanism stops working.

[0089] 4. During the experiment, ensure that the fault lower disc is in a fixed state.

[0090] 5. Record the strain and local deformation of the ductile pipe piece and the damage at other positions during the experiment.

[0091] 6. After the experiment ends, recover the experimental device as required.

[0092] B: simulate the influence of sudden displacement of the fracture zone under the action of earthquake on the stress state and deformation of the ductile pipe piece.

[0093] 1. Before the experiment starts, ensure that the fault upper disc jack is in working condition, the inclination angle of the fault upper disc jack is consistent with the inclination angle of the fracture surface simulation steel plate, and the top of the fault upper disc jack is in contact with the fault upper disc bottom plate.

[0094] 2. The fault upper disc is fixed by the iron hooks on both sides of the counterforce frame through ropes.

[0095] 3. Remove the fault upper disc jack at the bottom of the fault upper disc to make the fault upper disc in a suspended state.

[0096] 4. Place rubber pads or sponge pads at the bottom of the fault upper disc to play a buffering role.

[0097] 5. During the experiment, ensure that the fault lower disc is in a fixed state.

[0098] 6. Cut the rope of the fault upper disc to make it fall freely.

[0099] 7. Record the strain and local deformation of the ductile pipe piece and the damage at other positions during the experiment.

[0100] 8. After the experiment ends, recover the experimental device as required.

[0101] The above description is further detailed in connection with specific preferred embodiments of the present application, and it is not to be construed that the specific implementation of the present application is limited to these descriptions. For those skilled in the art to which the present application belongs, without departing from the concept of the present application, a number of simple deductions or substitutions can be made, and all of them should be considered as falling within the protection scope of the present application.

Claims

1. A ductile pipe section suitable for use at a fault zone, characterised in that: It includes arc-shaped segment main body, the middle part of the segment main body is provided with shear joint for filling concrete, shear joint is provided with shear type force sensor, the segment main body is connected by elastic component between the opposite sides in shear joint;The segment main body is embedded with steel plate component and water-swelling sealing strip, the water-swelling sealing strip is located between the steel plate component and segment main body;The upper and lower sides of the segment main body are provided with bolt hole for connecting with adjacent segment main body; The steel plate component includes fixed steel plate on the upper and lower sides, the left and right sides of the steel plate component are movable steel plate that can move left and right, the segment main body is connected with movable steel plate through double-acting jack; The segment main body is provided with reserved hole on the outside of movable steel plate, the double-acting jack is located in the reserved hole, one end of the double-acting jack is connected with the segment main body, and the other end is connected with movable steel plate through connecting piece; By setting shear joint, shear joint is provided with shear type force sensor, shear type force sensor plays the role of positioning damage position and transmitting earthquake signal, the position of tunnel that will be damaged can be determined through sensor;According to the signal received by receiver, double-acting jack is started to work, and movable steel plate is moved to left and right directions respectively.

2. A duct segment suitable for use at a fault zone according to claim 1, characterised in that: The connecting piece is steel strand.

3. A duct segment suitable for use at a fault zone according to claim 1, characterized in that: The upper and lower sides of the segment main body are provided with recess for setting water-swelling sealing strip.

4. The flexible pipe section suitable for use at a fracture zone according to claim 1, wherein: The segment main body is connected to form segment ring, adjacent segment main bodies are connected through bolt, and adjacent segment rings are connected through bolt.

5. A duct segment suitable for use at a fault zone according to claim 4, characterised in that: Water-swelling sealing strip is arranged in the joint of adjacent segment main bodies, and connecting steel plate is arranged between adjacent segment rings, and water-swelling sealing strip is arranged between the connecting steel plate and segment ring.

6. A duct segment suitable for use at a fault zone according to claim 4, wherein: It includes ordinary segment at both ends, the ordinary segment is connected with segment ring through bolt, the ordinary segment is embedded in soil body, and ductile segment is located at fracture surface.

7. A simulation apparatus for a flexible pipe section adapted for use at a fracture zone as claimed in claim 6, characterised in that: It includes base, counterforce frame is arranged on the base, hydraulic loading mechanism is arranged on the top of counterforce frame, fault lower plate and fault upper plate are arranged on the base, and hydraulic loading mechanism faces fault lower plate and fault upper plate; The fault lower plate includes fault lower plate bottom plate, two fault lower plate side plates, fault lower plate front plate and fault lower plate top plate arranged on the top, the fault upper plate includes fault upper plate bottom plate, two fault upper plate side plates, fault upper plate front plate and fault upper plate top plate arranged on the top, the middle part of fault upper plate front plate and fault lower plate front plate is provided with opening hole consistent with the outer diameter size of ductile segment to be tested, the fault lower plate bottom plate is fixedly connected with bottom plate through fixing component, the fault upper plate bottom plate is connected with bottom plate through fault upper plate jack, and the segment tunnel to be tested is located in fault upper plate and fault lower plate, and ordinary segment at both ends is sealingly connected with fault upper plate front plate and fault lower plate front plate respectively. The fracture surface simulation steel plate is provided between the lower wall and the upper wall of the fault, and the middle part of the fracture surface simulation steel plate is provided with a hole with the same size as the outer diameter of the pipe tunnel.

8. The apparatus for simulated experimentation of a ductile pipe segment suitable for use at a fault zone according to claim 7, wherein: The counter-force frame is inverted U-shaped, and the two lower wall side plates are connected to the lower wall bottom plate by screws or buckles.

9. An experimental method for a simulation experiment device for a ductile pipe segment at a fracture zone according to claim 7 or 8, characterized in that, The method comprises the following steps: Step S1, install the simulation experiment device for the ductile pipe segment at the fracture zone, fix the simulation experiment device for the ductile pipe segment at the fracture zone on the ground, and fix the upper wall jack and the fixing member on the base by bolts; lay the first layer of soil, and the height of the soil is flush with the bottom of the middle hole of the front plate of the lower wall and the front plate of the upper wall; after laying the soil, the soil is tamped; Step S2, install the first ring of pipe segments of the pipe tunnel to be tested on the upper cover front plate of the fault by bolts and gaskets, and attach strain gauges to the shear joints of the pipe bodies; then, sequentially splice the next pipe segment ring and strain gauges, and repeat the above operation until all the pipe segments for testing are spliced; finally, install the last pipe segment ring on the lower cover front plate of the fault by bolts and gaskets; Step S3, near the fracture surface, the pipe bodies are reinforced by high-strength bolts, and water-swelling waterstop strips are arranged at the joints of adjacent pipe bodies and at the joints of adjacent pipe segment rings; Step S4, after splicing, continue to lay the soil layer by layer, and tamp the soil to ensure that the soil is in a dense state; Step S5, align and install the top plate of the lower wall with the side plates and the front plate of the lower wall by bolts or buckles, and align and install the top plate of the upper wall with the side plates and the front plate of the upper wall by bolts or buckles; Step S6, perform a simulation of ground creep displacement or a simulation of sudden movement of the fracture zone under the action of an earthquake; The simulation of ground creep displacement comprises the following steps: Step S11, ensure that the upper wall jack is in a working state, so that the inclination angle of the upper wall jack is the same as the inclination angle of the fracture surface simulation steel plate, and the top of the upper wall jack is in contact with the bottom plate of the upper wall; Step S12, start the hydraulic loading device to apply a downward force to the upper wall, and simultaneously release the force of the upper wall jack at the bottom to enable the upper wall to move stably; during the experiment, ensure that the lower wall is in a fixed state; Step S13, after the displacement of the upper wall reaches the set value, stop the hydraulic loading mechanism; record the strain and local deformation of the ductile pipe segment and the damage at other positions during the experiment; The simulation of sudden movement of the fracture zone under the action of an earthquake comprises the following steps: Step S21, ensure that the jack on the hanging wall of the fault is in working condition, and the inclination angle of the jack on the hanging wall of the fault is the same as the inclination angle of the fracture surface simulation steel plate, the top of the jack on the hanging wall of the fault is in contact with the bottom plate of the hanging wall of the fault; Step S22, fix the hanging wall of the fault and the hook on it through a rope; Step S23, remove the jack on the hanging wall of the fault at the bottom of the hanging wall of the fault, so that the hanging wall of the fault is in a suspended state; Step S24, place a buffer pad at the bottom of the hanging wall of the fault; during the experiment, ensure that the bottom wall of the fault is in a fixed state; Step S25, remove or cut the rope of the hanging wall of the fault, so that it falls freely; record the strain and local deformation of the ductile pipe during the experiment, as well as the damage at other positions.

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