阅读说明：本技术 盾构隧道管片浮力测量模型实验装置 (Experimental device for buoyancy measurement model of shield tunnel segment ) 是由 杨建辉 陈峻屹 于 2019-10-18 设计创作，主要内容包括：本发明公开了一种盾构隧道管片浮力测量模型实验装置,其包括模拟隧道管片的内筒、与内筒形成环状间隙的外筒、固定并密封外筒的两侧挡板、测定浮力的力传感器和横梁；所述的横梁穿过两挡板和内筒,横梁两端位置固定；内筒的两端通过密封圈紧贴在两侧挡板上,横梁通过调节装置与内筒连接,所述的力传感器安装在调节装置上,挡板的侧部安装有注浆装置,所述的注浆装置与内外筒之间的环状间隙连通。本发明管片与浆液的动态变化过程与实际工程相符,从而为分析管片上浮机理提供便利,将浮力转换成拉力测量或压力测量,解决了内筒在浆液中难以测量浮力的问题,而且转换成拉力测量或压力测量后更加准确方便。(The invention discloses a shield tunnel segment buoyancy measurement model experimental device which comprises an inner cylinder for simulating a tunnel segment, an outer cylinder forming an annular gap with the inner cylinder, two side baffles for fixing and sealing the outer cylinder, a force sensor for measuring buoyancy and a cross beam, wherein the two side baffles are arranged on the inner cylinder; the beam passes through the two baffles and the inner cylinder, and the positions of two ends of the beam are fixed; the two ends of the inner cylinder are tightly attached to the baffles on the two sides through sealing rings, the cross beam is connected with the inner cylinder through an adjusting device, the force sensor is installed on the adjusting device, a grouting device is installed on the lateral portion of each baffle, and the grouting device is communicated with the annular gap between the inner cylinder and the outer cylinder. The dynamic change process of the pipe piece and the slurry conforms to the actual engineering, so that convenience is provided for analyzing the floating mechanism of the pipe piece, the buoyancy is converted into tension measurement or pressure measurement, the problem that the buoyancy of an inner cylinder in the slurry is difficult to measure is solved, and the method is more accurate and convenient after the buoyancy measurement or the pressure measurement is converted.)

1. A shield tunnel segment buoyancy measurement model experimental device is characterized by comprising an inner cylinder for simulating a tunnel segment, an outer cylinder forming an annular gap with the inner cylinder, two side baffles for fixing and sealing the outer cylinder, a force sensor for measuring buoyancy and a cross beam; the beam passes through the two baffles and the inner cylinder, and the positions of two ends of the beam are fixed; the two ends of the inner cylinder are tightly attached to the baffles on the two sides through sealing rings, the cross beam is connected with the inner cylinder through an adjusting device, the force sensor is installed on the adjusting device, a grouting device is installed on the side part of each baffle, and the grouting device is communicated with the annular gap between the inner cylinder and the outer cylinder; the baffle is provided with a round hole, the aperture of the round hole is smaller than the cylinder diameter of the inner cylinder, and the cross beam passes through the round hole;

the force sensor be pressure sensor, adjusting device symmetry set up including the left and right sides at section of thick bamboo center, adjusting device includes adjusting screw, adjusting nut and solid end nut, solid end nut inlay the inner wall at the inner tube, adjusting screw's top is connected with solid end nut, adjusting screw's lower part passes the crossbeam, adjusting nut connects the lower part at adjusting screw, pressure sensor cover establish on adjusting screw and press on adjusting nut, the crossbeam is pressed on pressure sensor.

2. The experimental device for the shield tunnel segment buoyancy measurement model according to claim 1, wherein the grouting device comprises a grouting pipe, a flow control valve and a funnel, the lower end of the grouting pipe penetrates through the baffle plate to be communicated with the annular gap, the funnel is installed at the upper end of the grouting pipe, and the flow control valve is installed on the grouting pipe.

3. The experimental device for the shield tunnel segment buoyancy measurement model according to claim 1, wherein holes are formed in four corners of the baffle respectively, the connecting rod penetrates through the holes to connect the baffle with two sides of the outer cylinder, and two ends of the connecting rod are fixed through connecting nuts.

4. The experimental device for the shield tunnel segment buoyancy measurement model according to claim 1, wherein both ends of the inner cylinder and both ends of the outer cylinder are open structures, the outer cylinder is provided with air outlets, the outer surface of the inner cylinder is wrapped with a metal mesh, and cement slurry is smeared on the outer surface of the metal mesh.

5. The experimental device for the shield tunnel segment buoyancy measurement model according to claim 1, wherein a contact surface of the sealing ring and the baffle is a smooth surface.

6. The experimental device for the shield tunnel segment buoyancy measurement model according to claim 1, wherein a first annular positioning block and a second annular positioning block are arranged on the inner side of the baffle; the lower end of the inner cylinder is positioned on the first annular positioning block, and the lower end of the outer cylinder is positioned on the second annular positioning block.

Technical Field

The invention belongs to the technical field of shield construction engineering, and particularly relates to a shield tunnel segment buoyancy measurement model experimental device.

Background

The shield construction method has the advantages of multiple aspects and is widely applied to the construction of urban subway tunnels. During construction by a shield method, the segments are assembled in the shield shell, the segments are separated from the shield tail along with forward propulsion of a shield machine, an annular gap is formed between the segments and a stratum, synchronous grouting is required to be carried out in the annular gap for controlling stratum displacement, and injected slurry is a mixture of water, cement, fly ash, an additive and the like. Before the slurry is solidified, the slurry is in a flowable state, and according to the Archimedes buoyancy principle, the slurry can generate buoyancy on the pipe piece, so that the pipe piece floats upwards. Duct piece dislocation can appear after the duct piece come-up, forms dislocation crack, reduces duct piece sealing quality, produces the phenomenon such as duct piece water leakage, consequently seems especially important to the research of duct piece come-up problem.

The section of jurisdiction is surrounded by the thick liquid in the actual engineering, and under thick liquid buoyancy, the section of jurisdiction come-up is arranged and is opened upper portion thick liquid, and the thick liquid flows down along the annular gap, and section of jurisdiction and thick liquid are all in motion state. By consulting related documents, Chinese patent CN108872297A discloses a model test device for shield tail grouting slurry condensation and segment floating process, when the device is used for testing, model soil is placed in a model box, a pressure box and other displacement sensors are pre-embedded in the model soil, a consolidation compression plate is placed on the upper side of the model soil, a compaction mechanism is used for applying pressure to the consolidation compression plate, and the model soil is compacted so as to simulate real soil layer compactness; and then taking out the consolidation compression plate, fixing the steel pipe piece model at the upper end of the model box through bolts, grouting between the steel pipe piece model and model soil through the side wall of the model box and grouting ports on the steel pipe piece model, pressing the model soil through the loading plate by using a pressing mechanism to simulate formation pressure, and controlling the pressure of the loading plate to simulate the floating process of the pipe piece in the solidification process of slurry.

Among the experimental apparatus of above-mentioned patent, the steel-pipe piece model is immovable, can not simulate the come-up process of section of jurisdiction, also can not simulate the flow process of thick liquid along annular gap, consequently can not simulate the come-up process of section of jurisdiction in the actual engineering, can't measure section of jurisdiction buoyancy, research section of jurisdiction come-up in-process buoyancy change law.

Disclosure of Invention

Based on the problems in the background art, the invention aims to provide a shield tunnel segment buoyancy measurement model experimental device, wherein a segment model in the device is surrounded by slurry, the slurry flows downwards when a segment floats, and the dynamic change process of the segment and the slurry is consistent with the actual engineering, so that the segment buoyancy is measured, the buoyancy change rule in the segment floating process is researched, and a foundation is laid for researching the segment floating control technology.

In order to achieve the purpose, the technical scheme provided by the invention is as follows:

the invention relates to a shield tunnel segment buoyancy measurement model experimental device, which comprises an inner cylinder for simulating a tunnel segment, an outer cylinder forming an annular gap with the inner cylinder, two side baffles for fixing and sealing the outer cylinder, a force sensor for measuring buoyancy and a cross beam, wherein the outer cylinder is provided with a plurality of annular gaps; the beam passes through the two baffles and the inner cylinder, and the positions of two ends of the beam are fixed; the two ends of the inner cylinder are tightly attached to the baffles on the two sides through sealing rings, the cross beam is connected with the inner cylinder through an adjusting device, the force sensor is installed on the adjusting device, a grouting device is installed on the lateral portion of each baffle, and the grouting device is communicated with the annular gap between the inner cylinder and the outer cylinder.

Preferably, the force sensor is a tension sensor, the adjusting devices are symmetrically arranged on the left side and the right side of the center of the inner barrel and comprise adjusting screw rods, adjusting nuts, fixed end nuts and fixing rods, the fixed end nuts are embedded in the inner wall of the inner barrel, the tops of the fixing rods are connected with the fixed end nuts, the lower parts of the adjusting screw rods penetrate through the cross beam, and the adjusting nuts are connected to the adjusting screw rods below the cross beam; the tension sensor is of a hollow structure, internal threads are arranged on the wall of a middle hole of the tension sensor, and the tension sensor is in threaded connection with the fixed rod above and the adjusting screw rod below respectively.

Preferably, force transducer be pressure sensor, adjusting device symmetry set up including the left and right sides at section of thick bamboo center, adjusting device includes adjusting screw, adjusting nut and solid end nut, solid end nut inlay the inner wall at the inner tube, adjusting screw's top is connected with solid end nut, adjusting screw's lower part passes the crossbeam, adjusting nut connects the lower part at adjusting screw, pressure sensor cover establish on adjusting screw and press on adjusting nut, the crossbeam is pressed on pressure sensor.

Preferably, the slip casting device include slip casting pipe, flow control valve and funnel, the slip casting pipe lower extreme pass the baffle and communicate with annular gap, the funnel is installed in the slip casting pipe upper end, flow control valve installs on the slip casting pipe.

Preferably, the four corners of the baffle are respectively provided with a hole, the connecting rod penetrates through the holes to connect the baffle with the two sides of the outer barrel, and the two ends of the connecting rod are fixed through connecting nuts. The connecting rods penetrate through the four holes respectively, the baffle and the two ends of the outer barrel are fixedly sealed, the structure is stable, a small amount of vaseline is smeared on the contact surfaces of the two baffles and the outer barrel, the baffles are made of polytetrafluoroethylene thin plates, the surface friction coefficient is extremely low, and the friction force between the inner barrel and the baffles on the two sides in the floating process can be reduced.

Preferably, the baffle is provided with a round hole, the aperture of the round hole is smaller than the cylinder diameter of the inner cylinder, and the cross beam penetrates through the round hole. The round hole makes things convenient for the installation of crossbeam, and provides the facility of operation for the experimentation.

Preferably, both ends of the inner cylinder and both ends of the outer cylinder are both in an open structure, and the outer cylinder is provided with an air outlet. The air outlet hole on the outer cylinder is used for discharging air in the outer cylinder when grouting is carried out in the outer cylinder.

Preferably, the outer surface of the inner cylinder is wrapped with a metal mesh, cement paste is smeared on the outer surface of the metal mesh, and the surface condition of the reinforced concrete segment can be simulated. The processing mode comprises the steps of polishing the outer surface of the inner cylinder to be rough, and then coating cement paste, or coating materials such as metal nets, cloth and the like, and then coating the cement paste.

Preferably, a first annular positioning block and a second annular positioning block are arranged on the inner side of the baffle; the lower end of the inner cylinder is positioned on the first annular positioning block, and the lower end of the outer cylinder is positioned on the second annular positioning block. The first annular positioning block and the second annular positioning block are used for determining the installation positions of the inner cylinder and the outer cylinder.

Preferably, the crossbeam on be equipped with two U type draw-in grooves, adjusting screw blocks in the U type draw-in groove.

Preferably, the contact surface of the sealing ring and the baffle is a smooth surface. The sealing ring is a U-shaped rubber sealing ring or a U-shaped sponge sealing ring, can be tightly attached to the baffle plates, prevents slurry from leaking into the inner barrel, and can reduce the friction force between the inner barrel and the baffle plates on the two sides in the floating process by spraying vaseline on the surface of the sealing ring.

Compared with the prior art, the technical scheme provided by the invention has the following beneficial effects:

1. the device simulates stratum by the inner cylinder simulation duct piece and the outer cylinder simulation stratum, and injects slurry into the outer cylinder to simulate the floating process of the duct piece.

2. The invention converts the buoyancy into tension measurement or pressure measurement, solves the problem that the buoyancy of the inner cylinder is difficult to measure in the slurry, and is more accurate and convenient after being converted into tension measurement or pressure measurement.

3. The floating process and the floating position of the inner cylinder can be controlled by rotating the adjusting nut, and the force sensor can realize real-time measurement. Therefore, the buoyancy change rule in the segment floating process can be conveniently researched.

Drawings

FIG. 1 is a schematic structural view of example 1 of the present invention;

FIG. 2 is a sectional view of example 1 of the present invention;

FIG. 3 is a schematic view of the connection structure of the tension sensor according to the present invention;

FIG. 4 is a schematic structural view of a cross-beam according to the present invention;

FIG. 5 is a schematic view of the construction of the baffle of the present invention;

FIG. 6 is a schematic structural view of example 2 of the present invention;

FIG. 7 is a sectional view of example 2 of the present invention.

Description of the labels in the schematic:

1-an inner cylinder; 2-outer cylinder; 3-a baffle plate; 4-a tension sensor; 5-a regulating device; 6-a cross beam; 7-sealing ring; 8-grouting devices; 9-a connecting rod; 10-a connecting nut; 11-a first annular locating block; 12-a second annular locating block; 13-pressure sensor, 21-air outlet; 31-holes; 32-round holes; 51-adjusting screw; 52-an adjusting nut; 53-end-fixing nuts; 54-a fixation rod; a 61-U-shaped clamping groove; 81-grouting pipe; 82-a flow regulating valve; and 83-a funnel.

Detailed Description

For further understanding of the present invention, the present invention will be described in detail with reference to examples, which are provided for illustration of the present invention but are not intended to limit the scope of the present invention.

Example 1

As shown in fig. 1 and fig. 2, the present embodiment relates to a shield tunnel segment buoyancy measurement model experimental device, which includes an inner cylinder 1 for simulating a tunnel segment, an outer cylinder 2 forming an annular gap with the inner cylinder 1, two side baffles 3 for fixing and sealing the outer cylinder 2, a tension sensor 4 for measuring the buoyancy of the inner cylinder 1, and a cross beam 6; the cross beam 6 penetrates through the two baffles 3 and the inner cylinder 1, and the positions of two ends of the cross beam 6 are fixed; two ends of the inner cylinder 1 are tightly attached to the baffle plates 3 on two sides through sealing rings 7, the cross beam 6 is connected with the inner cylinder 1 through an adjusting device 5, the tension sensor 4 is installed on the adjusting device 5, a grouting device 8 is installed on the side portion of each baffle plate 3, and the grouting device 8 is communicated with an annular gap between the inner cylinder and the outer cylinder.

As shown in fig. 1, 3 and 4, the adjusting devices 5 are symmetrically arranged at two sides of the center of the inner cylinder 1, each adjusting device 5 includes an adjusting screw 51, an adjusting nut 52, a fixed end nut 53 and a fixing rod 54, the fixed end nut 53 is embedded in the inner wall of the inner cylinder 1, the top of the fixing rod 54 is connected with the fixed end nut 53, the tension sensor 4 is of a hollow structure, an internal thread is arranged on the wall of a middle hole of the tension sensor 4, the lower end of the fixing rod 54 is in threaded connection with the tension sensor 4, the lower part of the adjusting screw 51 is clamped in the U-shaped clamping groove 61 of the cross beam 6, the upper end of the adjusting screw 51 is in threaded connection with the tension sensor 4, and the adjusting nut 52 is connected to the adjusting screw 51 below the cross beam 6, so that the cross beam 6 is pressed on the adjusting nut 52.

As shown in fig. 1, the grouting device 8 includes a grouting pipe 81, a flow control valve 82 and a funnel 83, the lower end of the grouting pipe 81 passes through the baffle 3 to communicate with the annular gap, the funnel 83 is installed at the upper end of the grouting pipe 81, and the flow control valve 82 is installed on the grouting pipe 81 for controlling grouting.

As shown in fig. 2 and 5, holes 31 are respectively formed at four corners of the baffle 3, the connecting rod 9 passes through the holes 31 to connect the baffle 3 with two sides of the outer cylinder 2, and two ends of the connecting rod 9 are fixed by the connecting nuts 10. Pass connecting rod 9 respectively in four holes 31, with the both ends fixed seal of baffle 3 and urceolus 2, the structure is firm, paints a small amount of vaseline in the contact surface department of two baffles 3 and urceolus 2, baffle 3 adopts the polytetrafluoroethylene sheet metal, and coefficient of surface friction is minimum, can reduce inner tube 1 come-up in-process and the frictional force of both sides baffle 3.

The baffle 3 is provided with a round hole 32, the aperture of the round hole 32 is smaller than the diameter of the inner cylinder 1, when the inner cylinder 1 floats upwards, the inner cylinder 1 is always positioned at the periphery of the round hole 32, and the cross beam 6 penetrates through the round hole 32. The round hole 32 facilitates the installation of the cross beam 6 and provides convenience for the operation of the experimental process.

As shown in fig. 1, both ends of the inner cylinder 1 and both ends of the outer cylinder 2 are open, and the outer cylinder 2 is provided with an air outlet 21. The air outlet 21 of the outer cylinder 2 is used for discharging air in the outer cylinder 2 when injecting slurry into the outer cylinder 2. The outer surface of the inner cylinder 1 is wrapped with a metal mesh, cement paste is smeared on the outer surface of the metal mesh, and the surface condition of the reinforced concrete segment can be simulated. The processing mode comprises the steps of polishing the outer surface of the inner barrel 1 to be rough, and then coating cement paste, or coating materials such as metal meshes and cloth and then coating the cement paste.

A first annular positioning block 11 and a second annular positioning block 12 are arranged on the inner side of the baffle 3; the lower end of the inner cylinder 1 is positioned on a first annular positioning block 11, and the lower end of the outer cylinder 2 is positioned on a second annular positioning block 12. The first annular positioning block 11 and the second annular positioning block 12 are used for determining the installation positions of the inner cylinder 1 and the outer cylinder 2.

The contact surface of the sealing ring 7 and the baffle 3 is a smooth surface. The sealing ring 7 is a U-shaped rubber sealing ring or a U-shaped sponge sealing ring, can be tightly attached to the baffle 3, prevents slurry from leaking into the inner barrel, and can reduce the friction force between the inner barrel 1 and the baffle 3 on the two sides in the floating process by spraying and gathering vaseline on the surface of the sealing ring 7.

The specific installation process of this embodiment is as follows:

the method comprises the following steps: the inner wall of the inner cylinder 1 is embedded with a fixed end nut 53, the two ends of the inner cylinder 1 are sleeved with the sealing rings 7, at the moment, gaps are reserved between the sealing rings 7 and the two end faces of the inner cylinder 1, and the distance between the two end faces of the sealing rings 7 is slightly larger than the length of the outer cylinder 1. The upper end of the fixing rod 54 is screwed into the fixing end nut 53, the tension sensor 4 is respectively connected with the lower end of the fixing rod 54 and the upper end of the adjusting screw 51, the adjusting nut 52 is screwed into the lower part of the adjusting screw 51, and the inner cylinder 1 is loaded into the outer cylinder 2.

Step two: baffle 3 is placed in the outside of inner tube 1, urceolus 2, and inner tube 3 is placed on first annular locating piece 11, and urceolus 2 is placed on second annular locating piece 12, and rotatory urceolus 2 guarantees that venthole 21 is located directly over. The connecting rod 9 penetrates through the holes 31 at the four corners of the two side baffles 3, the connecting nut 10 is screwed to tightly press and seal the two side baffles 3 and the outer cylinder 2, meanwhile, the sealing ring 7 slides along the inner cylinder 1, and the two side baffles 3 are tightly attached to the sealing ring 7.

Step three: the beam 6 is inserted into the inner cylinder 1 through the round hole 32, and the two adjusting screws 51 are clamped into the U-shaped groove 61. The two sides of the beam 6 are fixed, so that the beam 6 is ensured not to move. The adjusting nut 52 is rotated to contact the cross beam 6, and the tension sensor 4 is adjusted and connected to a data acquisition instrument (not shown). The grout pipe 81 is installed.

The present embodiment uses the principle:

the method comprises the following steps: after the experimental device is debugged, sufficient slurry is mixed, the slurry is injected into the gap between the inner cylinder 1 and the outer cylinder 2 through the grouting pipe 81, air in the outer cylinder 2 is discharged from the air outlet 21, and the regulating valve 82 is closed until the slurry is filled in the whole annular gap.

Step two: the inner cylinder 1 floats upwards under the buoyancy effect of slurry, the fixing rod 54 is driven by the inner cylinder 1 to move upwards, the two ends of the tension sensors 4 are respectively subjected to the tension of the fixing rod 54 and the adjusting screw rod 51, the sum of the tension of the two tension sensors 4 is equal to the buoyancy of the inner cylinder 1, and therefore the buoyancy of the inner cylinder 1 can be measured through the tension sensors 4.

Step three: during the test, the two adjusting nuts 52 can be rotated downwards for a certain distance, the inner cylinder 1 floats upwards for the same distance under the action of buoyancy, the tension sensor 4 measures the buoyancy at the position, and the buoyancy when the inner cylinder 1 floats to different positions can be measured by analogy until the inner cylinder 1 floats to a balance position. And (4) after the test is finished, detaching the baffle 3, taking out the inner cylinder 1 and cleaning the test device.

Example 2

As shown in fig. 6 and 7, the present embodiment relates to a pressure type experimental device for measuring a buoyancy model of a shield tunnel segment, which comprises an inner cylinder 1 for simulating a tunnel segment, an outer cylinder 2 forming an annular gap with the inner cylinder 1, two side baffles 3 for fixing and sealing the outer cylinder 2, a pressure sensor 13 for measuring the buoyancy of the inner cylinder 1, and a cross beam 6; the cross beam 6 penetrates through the two baffles 3 and the inner cylinder 1, and the positions of two ends of the cross beam 6 are fixed; the two ends of the inner cylinder 1 are tightly attached to the baffle plates 3 on the two sides through the sealing rings 7, the cross beam 6 is connected with the inner cylinder 1 through the adjusting device 5, the pressure sensor 13 is installed on the adjusting device 5, the grouting device 8 is installed on the lateral part of the baffle plate 3, and the grouting device 8 is communicated with the annular gap between the inner cylinder and the outer cylinder.

As shown in fig. 4 and 6, the adjusting devices 5 are symmetrically arranged at the left side and the right side of the center of the inner cylinder 1, each adjusting device 5 comprises an adjusting screw 51, an adjusting nut 52 and a fixed end nut 53, the fixed end nut 53 is embedded in the inner wall of the inner cylinder 1, the top of the adjusting screw 51 is connected with the fixed end nut 53, the cross beam 6 is provided with two U-shaped clamping grooves 61, the lower part of the adjusting screw 51 is clamped in the U-shaped clamping grooves 61, the pressure sensor 13 is sleeved on the adjusting screw 51, the adjusting nut 52 is screwed in the lower part of the pressure sensor 13, so that the cross beam 6 presses on the pressure sensor 13, and the pressure sensor 13 presses on the adjusting nut 52.

As shown in fig. 6, the grouting device 8 includes a grouting pipe 81, a flow control valve 82 and a funnel 83, wherein the lower end of the grouting pipe 81 passes through the baffle 3 to communicate with the annular gap, the funnel 83 is installed at the upper end of the grouting pipe 81, and the flow control valve 82 is installed on the grouting pipe 81 for controlling grouting.

As shown in fig. 5 and 7, holes 31 are respectively formed at four corners of the baffle 3, the connecting rod 9 passes through the holes 31 to connect the baffle 3 with two sides of the outer cylinder 2, and two ends of the connecting rod 9 are fixed by the connecting nuts 10. Pass connecting rod 9 respectively in four holes 31, with the both ends fixed seal of baffle 3 and urceolus 2, the structure is firm, paints a small amount of vaseline in the contact surface department of two baffles 3 and urceolus 2, baffle 3 adopts the polytetrafluoroethylene sheet metal, and coefficient of surface friction is minimum, can reduce inner tube 1 come-up in-process and the frictional force of both sides baffle 3.

The baffle 3 is provided with a round hole 32, the aperture of the round hole 32 is smaller than the diameter of the inner cylinder 1, when the inner cylinder 1 floats upwards, the inner cylinder 1 is always positioned at the periphery of the round hole 32, and the cross beam 6 penetrates through the round hole 32. The round hole 32 facilitates the installation of the cross beam 6 and provides convenience for the operation of the experimental process.

As shown in fig. 6, both ends of the inner cylinder 1 and both ends of the outer cylinder 2 are open, and the outer cylinder 2 is provided with an air outlet 21. The air outlet 21 of the outer cylinder 2 is used for discharging air in the outer cylinder 2 when injecting slurry into the outer cylinder 2.

The outer surface of the inner cylinder 1 is wrapped with a metal mesh, cement paste is smeared on the outer surface of the metal mesh, and the surface condition of the reinforced concrete segment can be simulated. The processing mode comprises the steps of polishing the outer surface of the inner barrel 1 to be rough, and then coating cement paste, or coating materials such as metal meshes and cloth and then coating the cement paste.

As shown in fig. 6 and 7, a first annular positioning block 11 and a second annular positioning block 12 are arranged inside the baffle 3; the lower end of the inner cylinder 1 is positioned on a first annular positioning block 11, and the lower end of the outer cylinder 2 is positioned on a second annular positioning block 12. The first annular positioning block 11 and the second annular positioning block 12 are used for determining the installation positions of the inner cylinder 1 and the outer cylinder 2.

The contact surface of the sealing ring 7 and the baffle 3 is a smooth surface. The sealing ring 7 is a U-shaped rubber sealing ring or a U-shaped sponge sealing ring, can be tightly attached to the baffle 3, prevents slurry from leaking into the inner barrel, and can reduce the friction force between the inner barrel 1 and the baffle 3 on the two sides in the floating process by spraying and gathering vaseline on the surface of the sealing ring 7.

The specific installation process of this embodiment is as follows:

the method comprises the following steps: the inner wall of the inner cylinder 1 is embedded with a fixed end nut 53, the two ends of the inner cylinder 1 are sleeved with the sealing rings 7, at the moment, gaps are reserved between the sealing rings 7 and the two end faces of the inner cylinder 1, and the distance between the two end faces of the sealing rings 7 is slightly larger than the length of the outer cylinder 1. The upper end of the adjusting screw 51 is screwed into the fixed end nut 53, the pressure sensor 13 is sleeved into the adjusting screw 51, the adjusting nut 52 is screwed in the lower part of the adjusting screw to prevent the pressure sensor 13 from sliding off, and the inner cylinder 1 is arranged in the outer cylinder 2.

Step two: baffle 3 is placed in the outside of inner tube 1, urceolus 2, and inner tube 3 is placed on first annular locating piece 11, and urceolus 2 is placed on second annular locating piece 12, and rotatory urceolus 2 guarantees that venthole 21 is located directly over. The connecting rod 9 penetrates through the holes 31 at the four corners of the two side baffles 3, the connecting nut 10 is screwed to tightly press and seal the two side baffles 3 and the outer cylinder 2, meanwhile, the sealing ring 7 slides along the inner cylinder 1, and the two side baffles 3 are tightly attached to the sealing ring 7.

Step three: the beam 6 is inserted into the inner cylinder 1 through the round hole 32, and the two adjusting screws 51 are clamped into the U-shaped groove 61. The two sides of the beam 6 are fixed, so that the beam 6 is ensured not to move. The adjusting nut 52 is rotated to ensure that the pressure sensor 13 is slightly pressed against the cross beam 6, and the pressure sensor 13 is adjusted and connected to a data acquisition instrument (not shown). The grout pipe 81 is installed.

The present embodiment uses the principle:

the method comprises the following steps: after the experimental device is debugged, sufficient slurry is mixed, the slurry is injected into the gap between the inner cylinder 1 and the outer cylinder 2 through the grouting pipe 81, air in the outer cylinder 2 is discharged from the air outlet 21, and the regulating valve 82 is closed until the slurry is filled in the whole annular gap.

Step two: the inner cylinder 1 floats upwards under the buoyancy effect of the slurry, the inner cylinder 1 drives the adjusting screw 51 to move upwards, the adjusting nut 52 applies pressure to the pressure sensors 13, the sum of the pressures of the two pressure sensors 13 is equal to the buoyancy of the inner cylinder 1, and the buoyancy of the inner cylinder 1 can be measured through the pressure sensors 13.

Step three: during the test, the two adjusting nuts 52 can be rotated downwards for a certain distance, the inner cylinder 1 floats upwards for the same distance under the action of buoyancy, the pressure sensor 13 measures the buoyancy of the position, and the buoyancy when the inner cylinder 1 floats to different positions can be measured by analogy until the inner cylinder 1 floats to a balance position. And (4) after the test is finished, detaching the baffle 3, taking out the inner cylinder 1 and cleaning the test device.

The present invention and its embodiments have been described above schematically, without limitation, and the embodiments of the present invention are shown in the drawings, and the actual structures are not limited thereto. Therefore, those skilled in the art should understand that they can easily and effectively design and modify the structure and embodiments of the present invention without departing from the spirit and scope of the present invention.