Test device for simulating internal water pressure of tunnel lining

Abstract

The present invention discloses a test device for simulating the internal water pressure of a tunnel lining, which includes a water pressure loading device and an internal support device. The internal support device is sleeved inside the lining, and a sealed internal water pressure cavity is formed between the internal support device and the lining. The internal water pressure cavity is provided with a water inlet pipe and an exhaust pipe, and the water inlet pipe is communicated with the water pressure loading device. The test device of the present invention forms a closed cavity through the internal support device and the tunnel lining, directly fills water into the cavity and pressurizes it, ensuring that the tunnel lining is subjected to uniform and stable water pressure, and can directly detect the construction quality of the tunnel lining concrete. At the same time, it can also detect the water stop effect between segments, providing reliable test data for the design and construction of the tunnel lining. The present invention combines the actual situation of the construction site, and the materials and equipment used are basically the same as those used in the on-site construction, which is convenient for scheduling and simple to operate, and has good economic benefits.

Description

Technical Field

[0001] The present invention relates to an experimental device for simulating high internal water pressure of a tunnel lining, belonging to the technical field of civil engineering. Background Art

[0002] In recent years, with the strong support of the state for the construction of water conveyance projects. In water conveyance projects, the prestressed lining of water conveyance tunnels is an important part of the project. During service, the tunnel lining is subjected to external water pressure, surrounding rock pressure, and internal water pressure. Under the action of high internal water pressure, the lining deforms outward, and tensile stress will be generated in the lining concrete. When the tensile stress reaches a certain level, the lining concrete will crack and even fail. Therefore, it is necessary to conduct an internal water pressure test to simulate the internal water pressure of the tunnel lining during service and determine the stress state of the tunnel lining during service.

[0003] The traditional methods for simulating internal water pressure mainly include the following two: One is to set reaction supports inside the tunnel lining and arrange several pads on the inner surface of the lining. Then, jacks located between the supports and the pads are loaded, and the applied load is transmitted to the lining through the pads to simulate the internal water pressure. This method is easy to construct, but due to the large diameter of the tunnel lining and the certain spacing of the pads, the lining will be locally subjected to concentrated forces, resulting in uneven local stress of the lining and unable to effectively simulate uniform internal water pressure. The other is at the construction site, where the two ends of the tunnel lining opening are blocked, and water is injected and pressurized through the water inlet hole and exhaust hole, and the water pressure is monitored by a pressure gauge. This method can achieve uniform internal water pressure, but the disadvantages are also obvious. Since the diameter of the tunnel lining is relatively large, the water consumption is large. The transportation and discharge of the test water and the corresponding supporting measures increase the difficulty of the test. At the same time, under the condition of high water pressure, there are strict requirements for the sealing of the two ends of the tunnel lining, and water seepage is likely to occur, and the high water pressure state cannot be continuously maintained.

[0004] At present, the device for simulating internal water pressure fixes a flexible container on a reliable reaction device. The part in contact with the inner surface of the tunnel lining adopts rubber material or thin steel plate, and the internal water pressure is simulated by pressurizing the flexible container with gas or liquid. When splicing this flexible container with a thin-walled structure, the splicing process requirements are relatively high. It is not easy to ensure the interface of the flexible container when it bears high pressure. In the case of simulating high internal water pressure, there is a problem of inconsistent deformation between the flexible container and the inner surface of the tunnel lining, and the inner surface of the tunnel lining cannot truly simulate the service state of the lining. Summary of the Invention

[0005] For the above reasons, the object of the present invention is to provide a test device for simulating high internal water pressure of a tunnel lining. This device can be used for in-situ tests outside the water conveyance tunnel, and can relatively realistically simulate the action of internal water pressure on the tunnel lining. In cooperation with the tunnel lining monitoring system and the external water pressure and surrounding rock pressure loading devices, it can determine the stress law of the tunnel lining, detect the construction quality of the lining and the water stop effect of the segments, and provide reliable test data for the design and construction of the tunnel lining.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] A test device for simulating internal water pressure of a tunnel lining includes a water pressure loading device and an internal support device. The internal support device is sleeved inside the lining, and a sealed internal water pressure cavity is formed between the internal support device and the lining. The internal water pressure cavity is provided with a water inlet pipe and an exhaust pipe, and the water inlet pipe is communicated with the water pressure loading device.

[0008] For the above test device for simulating internal water pressure of a tunnel lining, both ends of the internal support device and the lining are sealed by circumferential vertical plates, and a sealed internal water pressure cavity is formed among the internal support device, the circumferential vertical plates and the lining.

[0009] For the above test device for simulating internal water pressure of a tunnel lining, a water inlet valve and a water pressure gauge are arranged on the water inlet pipe, and an exhaust valve is arranged on the exhaust pipe.

[0010] For the above test device for simulating internal water pressure of a tunnel lining, radial ring plates and embedded ring plates are pre-embedded on the inner walls of both ends of the lining, and axial ring plates are also arranged on the inner walls of both ends of the lining. The radial ring plates are fixedly connected to the axial ring plates. The axial ring plates extend outside the lining. The top of the circumferential vertical plate is fixedly connected to the axial ring plate, and the bottom is fixedly connected to the internal support device.

[0011] For the above test device for simulating internal water pressure of a tunnel lining, the internal support device is composed of an outer steel cylinder, an inner steel cylinder and a concrete layer between the outer steel cylinder and the inner steel cylinder. The bottoms of the outer steel cylinder and the inner steel cylinder are straight sections, and the upper parts are arc-shaped consistent with the lining. I-beams are embedded in the concrete between the outer steel cylinder and the inner steel cylinder in the straight section, and longitudinal rib plates are embedded in the concrete between the outer steel cylinder and the inner steel cylinder in the upper part.

[0012] For the above test device for simulating internal water pressure in a tunnel lining, a ring support is sleeved inside the inner steel cylinder.

[0013] For the above test device for simulating internal water pressure in a tunnel lining, the outer steel cylinder and the inner steel cylinder are connected, and end plates are arranged at both ends of the outer steel cylinder and the inner steel cylinder.

[0014] For the above test device for simulating internal water pressure in a tunnel lining, a shield segment is arranged outside the lining and placed on a tunnel support.

[0015] The test device for water pressure inside the tunnel lining mentioned above, with both ends of the internal support device fixed on the internal support bearings.

[0016] The test device for water pressure inside the tunnel lining mentioned above, and a double I-beam is also arranged between the internal support bearings and the internal support device, making it more stable.

[0017] Adopting the above technical solution, the present invention has the following technical effects:

[0018] The test device of the present invention forms a sealed cavity through the internal support device and the tunnel lining, directly fills water and pressurizes the cavity, ensuring that the tunnel lining is subjected to uniform and stable water pressure, and can directly detect the construction quality of the tunnel lining concrete. At the same time, it can also detect the water stop effect between segments, providing reliable test data for the design and construction of the tunnel lining. Combining with the construction site situation, the materials and equipment used in the present invention are basically the same as those used in on-site construction, with convenient dispatching and simple operation, and having good economic benefits. Description of the Drawings

[0019] Figure 1 It is a schematic structural diagram of the present invention.

[0020] Figure 2 It is a schematic cross-sectional diagram of the present invention.

[0021] Figure 3 It is a structural diagram of the internal water pressure cavity of the present invention.

[0022] Figure 4 It is a schematic diagram of the water pressure loading device of the present invention.

[0023] In the figure: 1 - Lining; 2 - Shield segment; 3 - Internal support device; 4 - Internal water pressure cavity; 5 - Internal support bearing; 6 - Tunnel bearing; 7 - Exhaust valve; 8 - Water inlet valve; 9 - Water pressure gauge; 10 - Pressure stabilizing tank; 11 - Pressure stabilizing tank valve; 12 - Pressure water pump; 13 - Outer steel cylinder; 14 - Inner steel cylinder; 15 - Ring support; 16 - I-beam; 17 - Longitudinal rib plate; 18 - End plate; 19 - Double I-beam; 20 - Horizontal push plate; 21 - Circumferential vertical plate; 22 - Axial ring plate; 23 - Radial ring plate; 24 - Embedded ring plate; 25 - Concrete layer. Detailed Embodiments

[0024] As Figures 1-4 shown, a test device for simulating water pressure inside a tunnel lining includes a water pressure loading device and also includes an internal support device 3. The internal support device is sleeved inside the lining 1, and a shield segment 2 is also installed outside the lining. A sealed internal water pressure cavity 4 is formed between the internal support device and the lining. The internal water pressure cavity is provided with a water inlet pipe and an exhaust pipe, and the water inlet pipe is communicated with the water pressure loading device.

[0025] The test device for testing the internal water pressure of the tunnel lining of the present invention has an annular vertical plate 21 for sealing at both ends of the internal support device and the lining, and a sealed internal water pressure cavity 4 is formed between the internal support device 3, the annular vertical plate 21 and the lining 1.

[0026] The test device for testing water pressure in tunnel lining of the present invention comprises a water inlet valve 8 and a water pressure gauge 9 provided on the water inlet pipe, and an exhaust valve provided on the exhaust pipe.

[0027] The test device for the water pressure inside the tunnel lining is characterized in that radial ring plates 23 and embedded ring plates 24 are embedded in the inner walls of both ends of the lining, and axial ring plates 22 are also arranged on the inner walls of both ends of the lining. The radial ring plates and embedded ring plates are fixedly connected to the axial ring plates, and the axial ring plates extend out of the lining. The top of the annular vertical plate 21 is fixedly connected to the axial ring plate 22, and the bottom is fixedly connected to the internal support device 3. In order to make the whole more stable, a horizontal push plate 20 is also arranged on the outer side of the annular vertical plate.

[0028] The present invention has two radial ring plates, namely radial ring plate 23 and embedded ring plate 24.

[0029] The test device for the internal water pressure of the tunnel lining mentioned above, the internal support device is composed of an outer steel cylinder 13, an inner steel cylinder 14 and a concrete layer 25 between the outer steel cylinder and the inner steel cylinder, the bottom of the outer steel cylinder and the inner steel cylinder are straight sections, and the upper part is an arc shape consistent with the lining, an I-beam 16 is embedded in the concrete between the outer steel cylinder and the inner steel cylinder in the straight section, and a longitudinal rib 17 is embedded in the concrete between the outer steel cylinder and the inner steel cylinder in the upper part.

[0030] In the above-mentioned test device for water pressure in tunnel lining, a ring support 15 is sleeved inside the inner steel cylinder.

[0031] In the test device for the water pressure in the tunnel lining, the outer steel cylinder and the inner steel cylinder are connected, and end plates 18 are provided at both ends of the outer steel cylinder and the inner steel cylinder.

[0032] The test device for the water pressure in the tunnel lining is provided with a shield segment outside the lining and placed on the tunnel support 6.

[0033] In the above-mentioned test device for water pressure in tunnel lining, both ends of the inner support device are fixed on the inner support support 5, and double I-beams are arranged between the inner support support and the inner support device, which is more stable.

[0034] The lining 1 of the present invention is a prestressed lining structure with an inner diameter of 6400 mm and an outer diameter of 7500 mm, and a test length of 9960 mm.

[0035] For the internal water pressure cavity 4, it is necessary to pre-bury a 150-mm radial embedded ring plate 23 and an embedded ring plate 24 along the end section in the lining 1 in advance. Weld the axial ring plate 22 to the 150-mm radial embedded ring plate 23 and the embedded ring plate 24 and extend 100 mm beyond the end face of the lining 1. The axial ring plate 22 can be an integral part or welded in sections into one body. The thickness of the steel plate of the axial ring plate is 10 mm thick, and the other components use 20-mm thick steel plates.

[0036] The internal support device 3 is composed of an outer steel cylinder 13, an inner steel cylinder 14, a ring support 15, an I-beam 16, longitudinal rib plates 17, end plates 18, and a concrete layer 25. The thickness of the steel plate is 10 mm thick. The C50 concrete is the same as the concrete used for the lining. Longitudinal rib plates 17 are arranged along the outer steel cylinder 13 at intervals of 15°. Welding the I-beam 16 on the flat surface at the bottom is to ensure the structural safety of the internal support device 3 during lifting and the water pressure loading test. Double I-beams 19 at the support are to strengthen the support and ensure that the support does not fail.

[0037] After the concrete strength of the internal support device 3 reaches the requirements, use a jack to lift the internal support device to the predetermined position, lay pads at the internal support bearing, remove the jack, and place it on the internal support bearing 5. Weld a circumferential vertical plate 21 along the outer steel cylinder 13 and weld it to the axial ring plate 22 to form the internal water pressure cavity 4. Weld a horizontal push plate 20 on the outside of the circumferential vertical plate 21 and weld it to the outer steel cylinder 13 to prevent the lining end from being torn due to excessive horizontal force.

[0038] Inject water and pressurize the internal water pressure cavity through the pressure water pump 12. The pressure water pump 12 can adjust different outlet pressures. Open the valve 11 of the pressure stabilizing tank, the inlet valve 8, and the exhaust valve 7 until the internal water pressure cavity is filled with water. Close the pressure water pump 12 and all valves, stand still for a period of time according to the established plan, detect the airtightness of the internal water pressure cavity. After passing the detection, the pressure water pump 12 pressurizes and stabilizes step by step according to the plan until the specified simulated water pressure, and monitor the water pressure through the pressure water meter 9.

[0039] Open the exhaust valve 7 to slowly unload the water pressure, repeat the above pressurization process 2 times, simulate the filling and draining conditions of the tunnel lining, and collect the mechanical characteristics of the tunnel lining during this period through the monitoring system.

[0040] The technical means disclosed in the technical solution of the present invention are not limited to the technical means disclosed in the above embodiments, but also include technical solutions composed of any combination of the above technical features. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements are also regarded as the protection scope of the present invention.

Claims

1. An experimental device for simulating the internal water pressure of a tunnel lining, including a water pressure loading device, characterized in that: It further includes an internal support device. The internal support device is sleeved inside the lining. A sealed internal water pressure cavity is formed between the internal support device and the lining. The internal water pressure cavity is provided with a water inlet pipe and an exhaust pipe. The water inlet pipe is communicated with the water pressure loading device. At both ends of the internal support device and the lining, there are circumferential vertical plates for sealing. A sealed internal water pressure cavity is formed among the internal support device, the circumferential vertical plates and the lining. The internal support device is composed of an outer steel cylinder, an inner steel cylinder, and a concrete layer between the outer steel cylinder and the inner steel cylinder. The bottoms of the outer steel cylinder and the inner steel cylinder are straight sections, and the upper parts are arc-shaped consistent with the lining. I-beams are embedded in the concrete between the outer steel cylinder and the inner steel cylinder in the straight section, and longitudinal rib plates are embedded in the concrete between the outer steel cylinder and the inner steel cylinder in the upper part. Both ends of the internal support device are fixed on the internal support supports. Radial ring plates and embedded ring plates are pre-buried on the inner walls of both ends of the lining. Axial ring plates are further arranged on the inner walls of both ends of the lining. The radial ring plates are fixedly connected with the axial ring plates. The axial ring plates extend outside the lining. The tops of the circumferential vertical plates are fixedly connected with the axial ring plates, and the bottoms of the circumferential vertical plates are fixedly connected with the internal support device. A water inlet valve and a water pressure gauge are arranged on the water inlet pipe, and an exhaust valve is arranged on the exhaust pipe.

2. The test device for water pressure inside the tunnel lining according to claim 1, characterized in that: A ring support is sleeved inside the inner steel cylinder.

3. The test device for water pressure inside the tunnel lining according to claim 1, characterized in that: The outer steel cylinder and the inner steel cylinder are connected, and end plates are arranged at both ends of the outer steel cylinder and the inner steel cylinder.

4. The test device for water pressure inside the tunnel lining according to claim 1, characterized in that: A shield segment is arranged outside the lining, and the shield segment is placed on the tunnel support.

5. The test device for water pressure inside the tunnel lining according to claim 4, characterized in that: Double I-beams are further arranged between the internal support support and the internal support device, which is more stable.

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