Shield tunnel segment joint bearing performance small-scale model test device

Abstract

The utility model discloses a small-scale model test device for the bearing performance of a shield tunnel segment joint. The small-scale model test device comprises a segment, a segment joint, a vertical support system, a horizontal support system, a horizontal load reaction frame, a vertical load balancing system, a vertical load system, a vertical load distribution system and a horizontal load system. The pipe pieces are connected through the pipe piece joints; the horizontal load system, the horizontal load reaction frame and the horizontal support system are coordinated and matched to simulate horizontal axial force; and the vertical load system, the vertical support system, the vertical load distribution system and the vertical load balance system are coordinated and matched to simulate a bending moment. According to the device, accurate and constant graded loading of the segmental lining bending moment and the axial force is achieved through the weights, and the device is relatively simple in structure, low in test cost and beneficial to wide development of shield tunnel segmental lining model tests.

Description

Technical Field

[0001] The utility model relates to the field of indoor small-scale model tests, in particular to a small-scale model test device for the bearing performance of shield tunnel segment joints. Background Art

[0002] Tunnel linings constructed using the shield method are assembled from several prefabricated segments, connected by segment joints. Segment joints are a critical component of shield tunnel segment linings. Parameters such as the ultimate bearing capacity and rotational stiffness of segment joints directly influence the internal force distribution, deformation magnitude, and ultimate bearing capacity of the segment structure. The bearing capacity of segment joints can be analyzed and studied through full-scale tests, small-scale model tests, and numerical models. To conduct full-scale tests, some researchers have developed segment joint testing rigs. These rigs primarily utilize horizontal and vertical jacks to apply horizontal and vertical loads to paired shield segments to simulate the bending resistance of shield segment joints against positive and negative bending moments. During these tests, segments are typically curved. Extensive research on segment joints is limited by the bulky loading equipment, heavy segment weight, long test times, and high construction costs of full-scale tests. However, small-scale model tests, with their advantages of small size, short test cycles, low testing costs, and the ability to perform multiple tests, have become a valuable tool for underground engineering researchers. How to develop a small-scale segment joint model test device with relatively simple structure, stable and reliable performance, and wide application to provide an efficient means for studying the load-bearing mechanical properties of segment joints is a technical problem that urgently needs to be solved. Utility Model Content

[0003] The purpose of this utility model is to solve the problems faced by small-scale segment joint model test devices, such as how to accurately load and how to ensure the accuracy of test results. A small-scale model test device for the bearing performance of shield tunnel segment joints is proposed, thereby providing a more comprehensive and reliable test basis for the research work on the bending bearing performance of shield tunnel segment joints.

[0004] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0005] A small-scale model test device for the bearing performance of shield tunnel segment joints, including segments, segment joints, vertical support systems, horizontal support systems, horizontal load reaction frames, vertical load balancing systems, vertical load systems, vertical load distribution systems, and horizontal load systems. The vertical support system includes two vertical supports, the horizontal support system includes two horizontal supports, the horizontal load reaction frame includes a left reaction plate and a right reaction plate, the vertical load balancing system includes a horizontal steel base, a horizontal longitudinal beam, a vertical threaded rod, a fixing nut, an adjusting nut, and a vertical load distribution system. The load system includes vertical loading weights, vertical load weight plate, vertical loading column, vertical loading column positioning sleeve, sleeve positioning plate, fixing bolts, and fixing screws. The vertical loading column positioning sleeve is composed of a linear bearing. The vertical load distribution system includes a vertical load distribution beam and a pressure rod. The horizontal load system includes horizontal loading weights, a horizontal load weight plate, and a hydraulic cylinder. The hydraulic cylinder includes a vertical piston, a vertical piston rod, a horizontal piston, a horizontal piston rod, a cylinder body, a cylinder head, a cylinder head seal, a piston seal, a dust ring, a wear-resistant ring, and hydraulic oil.

[0006] The characteristics are as follows: both pipe segments are straight specimens, placed horizontally on vertical supports; the left and right side surfaces of the non-joint ends of the two pipe segments are in contact with the horizontal supports; the upper end surfaces of the two pipe segments are in contact with a pressure rod respectively; the joints of the two pipe segments are connected by pipe segment joints.

[0007] The two vertical supports are welded on the horizontal steel base, and the two vertical supports are parallel to each other; the two vertical supports are in contact with the bottom surface of the pipe segment, and the distances between the two vertical supports and the center of the pipe segment joint are the same.

[0008] The left horizontal support is welded to the right side surface of the horizontal piston rod, and the right horizontal support is welded to the left side surface of the right reaction plate.

[0009] The left reaction plate and the right reaction plate are vertically welded on the horizontal steel base, and the left reaction plate and the right reaction plate are parallel to each other.

[0010] Two pressure rods are welded on both sides of the lower end of the vertical load distribution beam, and the two pressure rods are parallel to each other; the two pressure rods are located above the pipe segment, and the distances from the two pressure rods to the center of the pipe segment joint are the same.

[0011] The horizontal steel base is a solid rectangular parallelepiped with four horizontal steel base threaded holes, and the horizontal longitudinal beam is a solid rectangular parallelepiped with two horizontal longitudinal beam threaded holes; the horizontal steel base is connected to two horizontal longitudinal beams on the same horizontal plane through four vertical threaded rods, and the horizontal steel base is fixed with a fixing nut, and the horizontal longitudinal beam is fixed with an adjusting nut.

[0012] The hydraulic cylinder is welded to the right side of the left reaction plate; a vertical piston rod is left at the upper end of the hydraulic cylinder; the vertical piston rod is perpendicular to the horizontal plane of the horizontal steel base; the horizontal load weight plate is welded to the upper end face of the vertical piston rod; the horizontal loading weight is directly placed on the horizontal load weight plate; a horizontal piston rod is left at the right end of the hydraulic cylinder; the cylinder head of the hydraulic cylinder is sealed with the cylinder body of the hydraulic cylinder; a dust ring and a cylinder head sealing ring are provided at the contact point between the vertical piston rod and the cylinder head; the vertical piston on the vertical piston rod is provided with two wear-resistant rings and a piston sealing ring; a dust ring and a cylinder head sealing ring are provided at the contact point between the horizontal piston rod and the cylinder head; the horizontal piston on the horizontal piston rod is provided with two wear-resistant rings and a piston sealing ring.

[0013] The vertical load weight plate is welded to the upper end surface of the vertical loading column; the vertical loading weight is placed directly above the vertical load weight plate; the vertical loading column is located in the vertical loading column positioning sleeve; the vertical loading column positioning sleeve is connected to the sleeve positioning plate by fixing screws, and the sleeve positioning plate is fixed to the horizontal longitudinal beam by fixing bolts; the sleeve positioning plate should be located directly above the center of the pipe segment joint.

[0014] In the vertical support system, both vertical supports are solid cylinders with smooth outer walls, and the material of both vertical supports is 45# steel.

[0015] In the horizontal support system, both horizontal supports are solid cylinders with smooth outer walls, and the material of the two horizontal supports is 45# steel; the center line of the horizontal support cylinder is always parallel to the horizontal center line of the side of the segment at the segment constraint end, and the heights are equal.

[0016] The left reaction plate and the right reaction plate of the horizontal load reaction frame are both made of 45# steel; the left reaction plate and the right reaction plate are both solid rectangular parallelepipeds.

[0017] In the vertical load balancing system, the horizontal steel base and the horizontal longitudinal beam are both made of 45# steel; the height of the horizontal longitudinal beam is adjusted by the adjusting nut on the vertical threaded rod.

[0018] In the horizontal load system, the hydraulic cylinder is L-shaped; the horizontal piston rod extends and retracts in the horizontal direction; the vertical piston rod extends and retracts in the vertical direction.

[0019] The pressure rod in the vertical load distribution system is a solid cylinder, and the vertical load distribution beam is a solid cuboid; both the pressure rod and the vertical load distribution beam are made of 45# steel; the vertical load distribution beam is symmetrical with the vertical loading column as the center.

[0020] In the vertical loading system, the vertical loading column is a solid cylinder with a smooth outer wall, and the material of the vertical loading column is 45# steel; the vertical loading column positioning sleeve contains a linear bearing inside, and the vertical loading column is in contact with the ball inside the linear bearing and the sliding direction is always vertical.

[0021] The utility model has the following beneficial effects:

[0022] (1) During the segment joint loading process, the horizontal load and the vertical load are independent of each other and do not affect each other, which allows for in-depth study of the effect of axial force on the rotational dynamic properties of the segment joint.

[0023] (2) The bending moment of the segment joint is generated only by the vertical load, which simplifies the calculation of the bending moment.

[0024] (3) This device can effectively control the transmission efficiency of the vertical load, that is, the vertical load will not be lost, thereby ensuring the precision and accuracy of the test.

[0025] (4) Vertical loads are applied using weights, which are more stable than jacks.

[0026] (5) This test device is low-cost and widely used. It can be used to test the bending stiffness and ultimate bearing capacity of pipe segment joints and compare reinforcement methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for describing the embodiments.

[0028] Figure 1 This is a front view of an application example proposed by the utility model.

[0029] Figure 2 This is a top view of the horizontal load system of an application example proposed by the utility model.

[0030] Figure 3 This is a top view of the pipe segment of an application example proposed by the utility model.

[0031] Figure 4 This is a top view of the vertical load distribution system of an application example proposed by the utility model.

[0032] Figure 5 This is a top view of the vertical load system of the application example proposed by the utility model.

[0033] Figure 6 for Figure 5 Cross-section of the vertical load system at AA.

[0034] Figure 7 This is a cross-sectional view of a hydraulic cylinder according to an application example of the present invention.

[0035] Figure 8 This is a schematic diagram of the position relationship between the pipe segments and the horizontal supports in the application example proposed by the utility model.

[0036] In the figure: 1 horizontal load weight plate, 2 horizontal loading weight, 3 sleeve positioning plate, 4 vertical load weight plate, 5 vertical loading weight, 6 vertical loading column positioning sleeve, 7 vertical loading column, 8 horizontal longitudinal beam, 9 vertical threaded rod, 10 adjustment nut, 11 horizontal longitudinal beam threaded hole, 12 fixing nut, 13 horizontal steel base threaded hole, 14 horizontal steel base, 15 right reaction plate, 16 horizontal support, 17 pressure rod, 18 pipe segment, 19 pipe segment Joint, 20 vertical support, 21 horizontal piston rod, 22 hydraulic cylinder, 23 left reaction plate, 24 vertical load distribution beam, 25 vertical piston rod, 26 fixing screw, 27 fixing bolt, 28 sleeve positioning plate threaded hole, 29 vertical loading column positioning sleeve threaded hole, 30 cylinder head, 31 piston sealing ring, 32 horizontal piston, 33 wear-resistant ring, 34 cylinder body, 35 vertical piston, 36 cylinder head sealing ring, 37 dust ring, 38 hydraulic oil. DETAILED DESCRIPTION

[0037] The technical solutions in the embodiments of the present invention will be further described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0038] Reference Figure 1-6 As shown, a small-scale model test device for the bearing performance of shield tunnel segment joints includes a segment 18, a segment joint 19, a vertical support system, a horizontal support system, a horizontal load reaction frame, a vertical load balancing system, a vertical load system, a vertical load distribution system, and a horizontal load system. The vertical support system includes two vertical supports 20, the horizontal support system includes two horizontal supports 16, the horizontal load reaction frame includes a left reaction plate 23 and a right reaction plate 15, the vertical load balancing system includes a horizontal steel base 14, a horizontal longitudinal beam 8, a vertical threaded rod 9, a fixing nut 12, and an adjusting nut 10, and the vertical load system includes a vertical load The weight 5, the vertical load weight plate 4, the vertical loading column 7, the vertical loading column positioning sleeve 6, the sleeve positioning plate 3, the fixing bolt 27, the fixing screw 26, the vertical loading column positioning sleeve 6 is composed of a linear bearing, the vertical load distribution system includes a vertical load distribution beam 24, a pressure rod 17, the horizontal load system includes a horizontal loading weight 2, a horizontal load weight plate 1, and a hydraulic cylinder 22. The hydraulic cylinder 22 includes a vertical piston 35, a vertical piston rod 25, a horizontal piston 32, a horizontal piston rod 21, a cylinder body 34, a cylinder head 30, a cylinder head sealing ring 36, a piston sealing ring 31, a dust ring 37, a wear-resistant ring 33, and hydraulic oil 38.

[0039] (1) Assembling the device.

[0040] ① First, pass the lower ends of the four vertical threaded rods 9 through the threaded holes 13 of the horizontal steel base, and fix the horizontal steel base 14 through the fixing nuts 12. Pass the upper ends of the four vertical threaded rods 9 through the threaded holes 11 of the horizontal longitudinal beams, and fix the two horizontal longitudinal beams 8 through the adjusting nuts 10. The height of the two horizontal longitudinal beams 8 is adjusted by the adjusting nuts 10 on the vertical threaded rods 9.

[0041] ② Secondly, the left reaction plate 23 and the right reaction plate 15 are vertically welded to the left and right directions of the upper end surface of the horizontal steel base 14, and ensure that the left reaction plate 23 and the right reaction plate 15 are parallel to each other.

[0042] ③ Then weld two vertical supports 20 to the left and right directions of the upper end face of the horizontal steel base 14, weld a horizontal load weight plate 1 to the upper end face of the vertical piston rod 25 of the pre-customized hydraulic cylinder 22, place the horizontal loading weight 2 on the horizontal load weight plate 1 as needed, weld a horizontal support 16 to the right end face of the horizontal piston rod 21 of the hydraulic cylinder 22, and weld another horizontal support 16 to the left side face of the right reaction plate 15, and the two horizontal supports 16 are in the same horizontal plane.

[0043] ④ Then use the fixing bolt 27 to fix the sleeve positioning plate 3 to the middle of the upper end surface of the horizontal longitudinal beam 8 through the sleeve positioning plate threaded hole 28, and use the fixing screw 26 to fix the vertical loading column positioning sleeve 6 to the center position of the upper end surface of the sleeve positioning plate 3 through the vertical loading column positioning sleeve threaded hole 29, and prepare in advance the vertical loading column 7, two pressure rods 17 and the vertical load distribution beam 24 that can be placed inside the vertical loading column positioning sleeve 6.

[0044] ⑤ Finally, a vertical load weight plate 4 for placing the vertical loading weight 5 is welded to the upper end face of the vertical loading column 7, and the vertical loading column 7 is placed inside the vertical loading column positioning sleeve 6. The two pressure rods 17 are welded in parallel on the left and right sides of the lower end face of the vertical load distribution beam 24. The position of the welded vertical load distribution beam 24 should be below the vertical loading column 7, and the center point of the upper end face of the vertical load distribution beam 24 is located in the direction of the center connection line of the upper and lower end faces of the vertical loading column 7.

[0045] (2) Segment placement. Two straight segments 18 are connected with a segment joint 19 and placed on vertical supports 20. The upper end of the segment 18 contacts the pressure rod 17, and the horizontal line in the middle of the side of the segment 18 (not the joint end) contacts the horizontal support 16. The horizontal force provided by the hydraulic cylinder 22 generates a horizontal reaction force between the right reaction plate 15 and the horizontal support 16, and the segment 18 is horizontally tightened.

[0046] (3) Applying a horizontal load. Gradually add horizontal loading weights 2 to the horizontal loading weight plate 1 in the horizontal loading system. The hydraulic cylinder 22 in the horizontal loading system bears the gravity of the horizontal loading weights 2 on the horizontal loading weight plate 1. The hydraulic oil 38 inside the hydraulic cylinder 22 is then used to form a horizontal load through the horizontal piston rod 21 at the right end of the hydraulic cylinder 22. This horizontal load generates a horizontal axial force on the pipe segment joint 19.

[0047] (4) Applying vertical loads. Gradually add vertical loading weights 5 to the vertical loading weight plate 4 in the vertical loading system. Under the gravity of the vertical loading weights 5, the vertical loading column 7 contacts the balls contained in the linear bearing inside the vertical loading column positioning sleeve 6 and transmits the vertical load to the segment joint 19. This vertical load ultimately generates a bending moment on the segment joint 19.

[0048] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent replacements for some of the technical features therein. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A small-scale model test device for the bearing performance of shield tunnel segment joints, comprising segments, segment joints, a vertical support system, a horizontal support system, a horizontal load reaction frame, a vertical load balancing system, a vertical load system, a vertical load distribution system, and a horizontal load system. The vertical support system comprises two vertical supports, the horizontal support system comprises two horizontal supports, the horizontal load reaction frame comprises a left reaction plate and a right reaction plate, the vertical load balancing system comprises a horizontal steel base, a horizontal longitudinal beam, a vertical threaded rod, a fixing nut, an adjusting nut, and a vertical The load system includes vertical loading weights, vertical load weight plate, vertical loading column, vertical loading column positioning sleeve, sleeve positioning plate, fixing bolts, and fixing screws. The vertical loading column positioning sleeve is composed of a linear bearing. The vertical load distribution system includes a vertical load distribution beam and a pressure rod. The horizontal load system includes horizontal loading weights, a horizontal load weight plate, and a hydraulic cylinder. The hydraulic cylinder includes a vertical piston, a vertical piston rod, a horizontal piston, a horizontal piston rod, a cylinder body, a cylinder head, a cylinder head seal, a piston seal, a dust ring, a wear-resistant ring, and hydraulic oil.

2. A small-scale model test device for the bearing performance of shield tunnel segment joints according to claim 1, characterized in that: The two vertical supports are both solid cylinders with smooth outer walls, and the material of the two vertical supports is 45# steel.

3. A small-scale model test device for the bearing performance of shield tunnel segment joints according to claim 1, characterized in that: Both horizontal supports are solid cylinders with smooth outer walls, and the material of the two horizontal supports is 45# steel; the center line of the horizontal support cylinder is always parallel to the horizontal center line of the side of the pipe segment at the constraint end of the pipe segment, and the height is equal.

4. A small-scale model test device for the bearing performance of shield tunnel segment joints according to claim 1, characterized in that: The pressure rod is a solid cylinder, and the vertical load distribution beam is a solid cuboid; both the pressure rod and the vertical load distribution beam are made of 45# steel; the vertical load distribution beam is symmetrical with the vertical loading column as the center.

5. The small-scale model test device for the bearing performance of shield tunnel segment joints according to claim 1 is characterized in that: The hydraulic cylinder is L-shaped; the horizontal piston rod extends and retracts in the horizontal direction; the vertical piston rod extends and retracts in the vertical direction.

6. A small-scale model test device for the bearing performance of shield tunnel segment joints according to claim 1, characterized in that: The vertical loading column is a solid cylinder with a smooth outer wall, and the material of the vertical loading column is 45# steel; the linear bearing of the vertical loading column positioning sleeve is vertically oriented, and there are vertically arranged balls inside the linear bearing. The vertical loading column is in contact with the balls inside the linear bearing and the sliding direction is always vertical.

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