Assembly type working well model loading test device for pipeline jacking and use method
By using 3D printing to prepare caisson models and employing a top-to-top synchronous loading method, the problems of inaccurate control of material mechanical properties and blurred structural details in caisson model tests were solved. This enabled comparison of multiple models under the same environmental conditions, improving the accuracy of test results and their engineering reference value.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-14
- Publication Date
- 2026-04-10
AI Technical Summary
In existing caisson model tests, the control of material mechanical properties is imprecise, the structural details are vague, and it is difficult to conduct synchronous loading and comparison of multiple models under the same environmental conditions, resulting in large deviations in test results and low engineering reference value.
A prefabricated working shaft model loading test device for pipeline jacking is designed. The shaft model is prepared by 3D printing. The jacks and fiber rods are used to achieve synchronous loading on the top. Combined with displacement gauges and data acquisition equipment, the consistency of mechanical parameters of the model materials and the accurate simulation of structural details are ensured.
It improved the accuracy and comparability of model tests, provided a scientific and reliable basis for optimizing caisson structure schemes, and enhanced the similarity between the model and the prototype and the engineering reference value of the test results.
Smart Images
Figure CN121830299A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the field of model test, in particular to a kind of pipeline jacking with assembled working well model loading test device and method. BACKGROUND
[0002] In the field of construction engineering, in order to ensure the safety, reliability and economy of structure, the design scheme must be fully technically verified before construction. However, due to the characteristics of large size, long construction period and high investment cost of actual engineering, it is often difficult to implement direct entity test or on-site comparison of multiple schemes. Under this background, model test, as an economical, efficient and repeatable verification method, is widely used to simulate actual engineering behavior, evaluate structural performance and optimize design scheme.
[0003] At present, the model test research on open caisson and other special structures mostly uses the traditional geometric scaling method. However, this method often only focuses on the scaling of geometric size, and fails to accurately control the mechanical properties of model materials according to the similarity theory, resulting in significant deviation between the material constitutive relationship and the prototype structure. In addition, the existing tests generally simplify or blur the structural details, which cannot truly reflect the local stress state and structural behavior in actual engineering, thus reducing the engineering reference value of test results.
[0004] On the other hand, the existing open caisson model test mostly uses single model independent loading method, lacking effective devices for synchronous comparison test of multiple models under the same environmental conditions. Since the fluctuation of environmental factors (such as temperature, humidity and boundary conditions) will have an unavoidable impact on test results, the traditional method cannot realize fair comparison of different design schemes under the same external conditions, limiting the practical application effect of model test in scheme selection and optimization.
[0005] Therefore, in order to solve the above problems, it is urgent to develop a test device that can accurately control the mechanical properties of materials, reasonably simulate structural details, and simultaneously load and compare multiple models under the same environmental conditions, in order to improve the accuracy, comparability and engineering guiding significance of model test. SUMMARY
[0006] The purpose of the present application is to provide a kind of pipeline jacking with assembled working well model loading test device and method, to solve the problems raised in the above background.
[0007] To achieve the above purpose, the present application provides the following technical solutions: The utility model provides a kind of pipeline jacking with assembled working well model loading test device, including wooden board model box, symmetrically spaced distribution is provided with assembled caisson model and pouring type caisson model in the wooden board model box, adjustable height isolation box is installed in the gap between the assembled caisson model and pouring type caisson model, the isolation box is provided with horizontally sliding installation flatbed truck, jack is installed on the flatbed truck, and the side of jack is supported by fiber rod between the inner wall of pouring type caisson model, and the other side of jack is supported on the inner wall of assembled caisson model by another group of fiber rod; The sand in the wooden board model box is filled to be flush with the upper end port of the assembled caisson model and the pouring type caisson model, and the displacement meter connected transversely with the assembled caisson model and the pouring type caisson model is embedded in the sand, and the displacement meter is fixed in the wooden board model box by the displacement frame.
[0008] Preferably, the assembled caisson model is composed of three groups of assembly rings and a bottom sheet, the assembly ring is composed of a plurality of arc-shaped pipe pieces arranged in a circumferential array, the pipe pieces on the three groups of assembly rings are distributed in a circumferential staggered manner, and the pipe pieces are provided with connecting holes, the adjacent pipe pieces are connected by fixing and binding through the cotton thread penetrating the connecting holes, and the pipe pieces are provided with strain gauges and pressure gauges distributed and installed thereon.
[0009] Preferably, the pouring type caisson model and the assembled caisson model are both provided with through holes on the outer arc walls of the side close to the isolation box, the through holes are level with the positions of the fiber rods, the fiber rods extend along the through holes to the inner walls of the pouring type caisson model and the assembled caisson model, and the end portions of the fiber rods are provided with composite top plates composed of a plurality of gypsum boards and iron sheets.
[0010] Preferably, the outer wall of the fiber rod is sleeved with an isolation cover, a pair of side grooves are arranged on the inner arc walls of the through holes in a circumferential array, and a side strip is arranged on the middle segment of the outer arc wall of the isolation cover and slidably inserted into the side grooves.
[0011] Preferably, the isolation box is composed of a bottom plate, a protection frame and a cover plate, the bottom plate is provided with a horizontally extending track, the rollers at the lower end of the flatbed truck are installed on the track, and the jack on the flatbed truck extends to the outside of the wooden board model box through a pressure transmission pipe.
[0012] Preferably, a base is fixedly installed at the lower end of the inner cavity of the wooden board model box, and the upper end of the base is connected to the lower end of the bottom plate through a pair of vertically installed height-adjustable telescopic columns.
[0013] Preferably, the bottom plate is provided with upwardly extending extension supporting plates on both sides, and the lower ends of the assembled caisson model and the pouring type caisson model are pressed on the extension supporting plates.
[0014] Preferably, the two sides of the protection frame are provided with screw holes at the positions with the same height as the fiber rod, threaded connection screw pipes are rotatably installed in the screw holes, outer threads are arranged on the outer arc walls of the threaded connection screw pipes, and end threads are arranged on the ends of the threaded connection screw pipes and are in threaded connection with the ends of the isolation cover.
[0015] Preferably, the telescopic end of the jack is connected with a stepped telescopic head, a front section of the stepped telescopic head is slidingly sleeved with an end pipe connected with the end of the fiber rod, and a rear section of the stepped telescopic head is in threaded rotation connection with a top ring, and the end of the top ring is supported on the end of the end pipe.
[0016] A test method is realized by using the test device of the assembled working well model loading test for pipe jacking, and the test method comprises the following steps: Step one: firstly, the pipe piece is prepared and the assembled caisson model is assembled through 3D printing, then appropriate materials are selected according to the elastic modulus after scaling, cotton threads are selected to connect adjacent pipe pieces, and meanwhile, the diameters of the materials should meet the proportioning requirements of the model test, the materials are fixed on the pipe pieces through cementing, so that the connecting materials between adjacent pipe pieces can simulate the tensile stress when the pipe pieces are stressed; Step two: the stress receiving parts of the model are filled with a composite roof composed of plaster and iron plates, so that the model is uniformly stressed and the loading process is stable; Step three: a layer of sand is laid on the bottom of the wooden model box, the height of the sand is 1 / 2 of the height of the model, then the treated assembled caisson model and the cast-in-place caisson model are placed in the wooden model box, and the models are symmetrically placed in the center of the wooden model box, and a separation box is placed between the assembled caisson model and the cast-in-place caisson model, a flat car with fixed jacks is arranged in the separation box, high-strength fiber rods are placed in the separation cover, the fiber rods are located between the model and the jacks, and a small pre-pressure is given to the inner wall of the model through the jacks, so that the fiber rods can keep consistent with the direction of the jacking force during loading; Step four: then, the displacement meters are installed and arranged for detection, and are connected to the data acquisition equipment, finally, the remaining sand is filled into the wooden model box, and the filling is stopped when the sand is flush with the ports of the model, and the loading record can be made after no error is found.
[0017] Compared with the prior art, the beneficial effects of the present application are: The two different caisson models in the present application are placed in the same model box and are synchronously loaded in a "topping" mode, so that the consistency of the physical parameters of the soil around the models is effectively ensured, the result deviation caused by the difference in soil conditions in the traditional separate loading test is overcome, compared with the prior art, the technical difficulty and uncertainty of the control of the soil parameters are greatly reduced, the bearing capacity comparison of different caisson models under the same boundary conditions is more intuitive and accurate, and a more scientific and reliable test basis is provided for the optimization and comparison of the caisson structure schemes. The caisson model is prepared by using a 3D printing process, and key mechanical parameters such as the elastic modulus of the model material can be accurately controlled according to the similarity theory, and meanwhile, the details of the actual caisson structure can be accurately reproduced, so that the similarity between the model and the prototype is guaranteed in two aspects of material constitutive and geometric shape, and the reliability and engineering reference value of the model test result are significantly improved. BRIEF DESCRIPTION OF DRAWINGS
[0018] Figure 1 is a top view of the present application; Figure 2 is a structural schematic view of the present application; Figure 3 is a schematic view of the fiber rod mounting structure in Example 2 of the present application; Figure 4 is a schematic view of the assembled caisson model of the present application; Figure 5 is a schematic view of the segment of the present application.
[0019] In the figure: 1, wooden model box; 2, sand; 3, assembled caisson model; 31, segment; 311, connecting hole; 32, through hole; 33, side groove; 4, poured caisson model; 5, isolation box; 51, cover plate; 52, protective frame; 521, screw hole; 53, base; 54, bottom plate; 55, track; 56, telescopic column; 57, extended support plate; 6, flatbed truck; 7, displacement meter; 8, fiber rod; 9, isolation cover; 91, side strip; 10, jack; 11, pressure transmission pipe; 12, composite top plate; 13, displacement frame; 14, connecting screw pipe; 15, end pipe; 16, stepped telescopic head; 17, top ring. DETAILED DESCRIPTION
[0020] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.
[0021] Please refer to Figures 1 to 5 The present application provides a technical solution: Example 1: A loading test device for a prefabricated working shaft model for pipeline jacking includes a wooden model box 1. The wooden model box 1 contains symmetrically spaced prefabricated caisson models 3 and cast-in-place caisson models 4. The prefabricated caisson model 3 is composed of three sets of assembly rings and base plates stacked and connected. The assembly rings are composed of multiple sets of arc-shaped pipe segments 31 arranged in a circular array. The pipe segments 31 on the three sets of assembly rings are arranged in a circumferentially staggered manner, and the pipe segments 31 are provided with connection holes 311. Adjacent pipe segments 31 are fixedly tied together by cotton thread passing through the connection holes 311. Strain gauges and pressure gauges are installed on the pipe segments 31.
[0022] An adjustable-height isolation box 5 is installed in the gap between the prefabricated caisson model 3 and the cast-in-place caisson model 4. A horizontally sliding flatbed trolley 6 is installed in the isolation box 5, and a jack 10 is mounted on the flatbed trolley 6. One side of the jack 10 is supported by fiber rods 8 against the inner wall of the cast-in-place caisson model 4, and the other telescopic end of the jack 10 is supported by another set of fiber rods 8 against the inner wall of the prefabricated caisson model 3. Sand 2 is filled into the wooden model box 1 until it is flush with the upper ends of the prefabricated caisson model 3 and the cast-in-place caisson model 4. Pre-filled sand 2... A displacement gauge 7 is embedded in the prefabricated caisson model 3 and the cast-in-place caisson model 4. The displacement gauge 7 is fixed inside the wooden model box 1 by a displacement frame 13. A through hole 32 is opened on the outer arc wall of the cast-in-place caisson model 4 and the prefabricated caisson model 3 near the isolation box 5. The through hole 32 is at the same height as the fiber rod 8. The fiber rod 8 extends along the through hole 32 to the inner wall of the cast-in-place caisson model 4 and the prefabricated caisson model 3. A composite top plate 12 is provided at the end of the fiber rod 8. The composite top plate 12 is composed of multiple sets of gypsum board and iron plate stacks.
[0023] A test method based on a prefabricated working shaft model loading test device for pipeline jacking, the test method includes the following steps: Step 1: First, the preparation of the pipe segment 31 and the assembly of the prefabricated caisson model 3 are realized by 3D printing. Then, after scaling down according to the elastic modulus, a suitable material is selected, and cotton thread is used to connect adjacent pipe segments 31. At the same time, considering that the diameter of the material should meet the proportional requirements of the model test, it is fixed to the pipe segment 31 by gluing, so that the connecting material between adjacent pipe segments 31 can simulate the tensile stress when the pipe segment is subjected to force. Step 2: Fill the stress-bearing parts of the model with a composite top plate 12 made of plaster and iron plate to make the model bear the stress evenly and keep the loading process stable; Step three: a layer of sand 2 is laid on the bottom of the wooden model box 1, the height of the sand 2 is 1 / 2 of the height of the model 1, and the prepared assembly caisson model 3 and the pouring caisson model 4 are placed in the wooden model box 1, symmetrically placed in the center of the wooden model box 1, and the isolation box 5 is placed between the assembly caisson model 3 and the pouring caisson model 4, the flat car 6 with the fixed jack 10 is arranged in the isolation box 5, the high-strength fiber rod 8 is placed in the isolation cover 9, the fiber rod 8 is located between the model and the jack 10, and a small pre-pressure is given to the inner wall of the model through the jack 10, so that the fiber rod 8 can be consistent with the direction of the top force during loading; Step four: then install the displacement meter 7 for detection and connect to the data acquisition device, and finally fill the remaining sand 2 into the wooden model box 1, fill to the port of the model, and record the loading after no error.
[0024] Example 2: on the basis of example 1, due to the softness of the sand 2, it is difficult to control the consistency of the model with the fiber rod 8 and the jack 10 in the actual installation process, and the model is prone to unilateral tilt, and the fiber rod 8 only penetrates the model on one side, which is more prone to cause the center of gravity of the model to deviate.
[0025] The isolation box 5 is composed of a bottom plate 54, a protection frame 52 and a cover plate 51, the bottom plate 54 is provided with a transversely extending track 55, the rollers at the lower end of the flat car 6 are installed on the track 55, the jacks 10 on the flat car 6 extend to the outside of the wooden model box 1 through the pressure transmission pipe 11, the inner cavity of the wooden model box 1 is fixedly installed with a base 53, the upper end of the base 53 is connected to the lower end of the bottom plate 54 through a pair of vertically installed height-adjustable telescopic columns 56, the both sides of the bottom plate 54 are provided with upwardly extending extension supporting plates 57, and the lower ends of the assembly caisson model 3 and the pouring caisson model 4 are pressed on the extension supporting plates 57.
[0026] The movement direction of the flat car 6 is limited by the track 55, so as to ensure that the loading direction of the jack 10 is consistent with the installation position of the fiber rod 8, and deviation is avoided, the height of the isolation box 5 is adjusted through the telescopic column 56, so as to adapt to the installation of models of different heights, so that the height of the fiber rod 8 corresponds to the position of the through hole 32 on the model, and the installation height of the model is limited by the extension supporting plate 57, so as to avoid the change of the height of the model during installation due to the softness of the sand.
[0027] The outer wall of the fiber rod 8 is sleeved with the isolation cover 9, a pair of side grooves 33 are arranged on the inner wall of the circular arc of the through hole 32 in a circumferential array, the middle section of the outer wall of the circular arc of the isolation cover 9 is provided with a side strip 91 which is slidably inserted into the side groove 33, the two sides of the protective frame 52 are provided with screw holes 521 at the position with the same height as the fiber rod 8, the screw holes 521 are threadedly rotatably provided with connecting screw pipes 14, the outer wall of the connecting screw pipe 14 is provided with external threads which are threadedly rotatably connected with the screw holes 521, the end of the connecting screw pipe 14 is provided with end threads which are threadedly connected with the end of the isolation cover 9, the telescopic end of the jack 10 is connected with a stepped telescopic head 16, the front section of the stepped telescopic head 16 is slidably sleeved with an end pipe 15 which is connected with the end of the fiber rod 8, the rear section of the stepped telescopic head 16 is threadedly rotatably connected with a top ring 17, the end of the top ring 17 is supported on the end of the end pipe 15.
[0028] During the test installation process, the base 53 is first installed, the height of the isolation box 5 is adjusted by the telescopic column 56, then the fiber rod 8 is installed, the ends of the fiber rod 8 are supported by the transverse sliding of the flat car 6 between the cast-in-place caisson model 4 and the jack 10, then the fiber rod 8 and the jack 10 are fixedly connected, at this time the position of the flat car 6 is limited due to the fiber rod 8 on one side, therefore a gap appears between the fiber rod 8 on the other side and the telescopic end of the jack 10, the end pipe 15 is made to abut and fixedly connected with the end of the fiber rod 8 by the extension of the telescopic end of the jack 10, then the through holes 32 on the assembled caisson model 3 and the cast-in-place caisson model 4 are inserted into the isolation cover 9 outside the fiber rod 8 in a transverse translation manner along the extension supporting plate 57.
[0029] The position of the transverse insertion is limited by the cooperation of the side strip 91 and the side groove 33, and rotation deviation is avoided, the end of the fiber rod 8 is translated to abut on the composite top plate 12 on the inner wall of the model, the end pipe 15 is supported by the thread rotation of the top ring 17, and a small pre-pressure is applied to the fiber rod 8, then the isolation cover 9 is connected by the rotation of the connecting screw pipe 14, and finally the sand soil 2 is filled.
[0030] Although the embodiments of the present application have been shown and described, it is to be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present application, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A prefabricated working shaft model loading test device for pipeline jacking, comprising a wooden model box (1), characterized in that: The wooden model box (1) contains symmetrically spaced prefabricated caisson models (3) and cast-in-place caisson models (4). An adjustable-height isolation box (5) is installed in the gap between the prefabricated caisson models (3) and the cast-in-place caisson models (4). A horizontally sliding flatbed cart (6) is installed in the isolation box (5). A jack (10) is installed on the flatbed cart (6). One side of the jack (10) is supported by a fiber rod (8) against the inner wall of the cast-in-place caisson model (4). The other telescopic end of the jack (10) is supported by another set of fiber rods (8) against the inner wall of the prefabricated caisson model (3). The wooden model box (1) is filled with sand (2) until it is flush with the upper end of the prefabricated caisson model (3) and the cast-in-place caisson model (4). The sand (2) contains a displacement gauge (7) that is laterally connected to the prefabricated caisson model (3) and the cast-in-place caisson model (4). The displacement gauge (7) is fixed inside the wooden model box (1) by a displacement frame (13).
2. The prefabricated working shaft model loading test device for pipeline jacking according to claim 1, characterized in that: The prefabricated caisson model (3) is composed of three sets of assembly rings and bottom plates stacked together. The assembly ring is composed of multiple sets of arc-shaped tube segments (31) arranged in a circular array. The tube segments (31) on the three sets of assembly rings are arranged in a circular staggered distribution, and the tube segments (31) are provided with connection holes (311). Adjacent tube segments (31) are fixed and tied together by cotton thread passing through the connection holes (311). Strain gauges and pressure gauges are distributed and installed on the tube segments (31).
3. The prefabricated working shaft model loading test device for pipeline jacking according to claim 2, characterized in that: Both the cast-in-place caisson model (4) and the assembled caisson model (3) have through holes (32) on the outer arc wall of the side near the isolation box (5). The through holes (32) are at the same height as the fiber rods (8). The fiber rods (8) extend along the through holes (32) to the inner wall of the cast-in-place caisson model (4) and the assembled caisson model (3). The ends of the fiber rods (8) are provided with composite top plates (12), which are composed of multiple sets of gypsum board and iron plate stacks.
4. The prefabricated working shaft model loading test device for pipeline jacking according to claim 3, characterized in that: The outer wall of the fiber rod (8) is fitted with an isolation cover (9), and a pair of side grooves (33) arranged in a circular array are provided on the inner arc of the through hole (32). The middle section of the outer arc of the isolation cover (9) is provided with a side strip (91) that is slidably inserted into the side groove (33).
5. The prefabricated working shaft model loading test device for pipeline jacking according to claim 4, characterized in that: The isolation box (5) is composed of a base plate (54), a protective frame (52) and a cover plate (51). A horizontally extending track (55) is provided on the base plate (54). The rollers at the lower end of the flatbed (6) are installed on the track (55). The jack (10) on the flatbed (6) extends to the outside of the wooden model box (1) through the pressure transmission pipe (11).
6. The prefabricated working shaft model loading test device for pipeline jacking according to claim 5, characterized in that: The lower end of the inner cavity of the wooden model box (1) is fixedly installed with a base (53), and the upper end of the base (53) is connected to the lower end of the base plate (54) through a pair of vertically installed adjustable telescopic columns (56).
7. The prefabricated working shaft model loading test device for pipeline jacking according to claim 5, characterized in that: The base plate (54) is provided with upwardly extending support plates (57) on both sides, and the lower ends of the prefabricated caisson model (3) and the cast-in-place caisson model (4) are pressed onto the extension support plates (57).
8. The prefabricated working shaft model loading test device for pipeline jacking according to claim 7, characterized in that: The protective frame (52) has screw holes (521) at the same height as the fiber rod (8) on both sides. A connecting screw tube (14) is rotatably installed in the screw hole (521). The outer arc wall of the connecting screw tube (14) is provided with an external thread that is rotatably connected to the screw hole (521). The end of the connecting screw tube (14) is provided with an end thread that is threaded to the end of the isolation cover (9).
9. A prefabricated working shaft model loading test device for pipeline jacking according to claim 8, characterized in that: The telescopic end of the jack (10) is connected to a stepped telescopic head (16). The front section of the stepped telescopic head (16) is slidably sleeved with an end tube (15) connected to the end of the fiber rod (8). The rear section of the stepped telescopic head (16) is threadedly rotatably connected to a top ring (17). The end of the top ring (17) is held against the end of the end tube (15).
10. A test method implemented by the prefabricated working shaft model loading test device for pipeline jacking according to any one of claims 1-9, characterized in that: The experimental method includes the following steps: Step 1: First, the preparation of the pipe segment (31) and the assembly of the prefabricated caisson model (3) are realized by 3D printing. Then, according to the elastic modulus, a suitable material is selected and cotton thread is used to connect the adjacent pipe segments (31). At the same time, considering that the diameter of the material should meet the proportional requirements of the model test, it is fixed to the pipe segment (31) by gluing so that the connecting material between the adjacent pipe segments (31) can simulate the tensile stress when the pipe segment is subjected to force. Step 2: Fill the stress-bearing parts of the model with a composite top plate (12) made of plaster and iron plate to make the model uniformly stressed and keep the loading process stable; Step 3: Lay a layer of sand (2) at the bottom of the wooden model box (1). The height of the sand (2) is 1 / 2 of the model height. Then put the prepared prefabricated caisson model (3) and cast-in-place caisson model (4) into the wooden model box (1) and place them symmetrically in the center of the wooden model box (1). Place an isolation box (5) between the prefabricated caisson model (3) and the cast-in-place caisson model (4). Set up a flatbed cart (6) with a fixed jack (10) inside the isolation box (5). Put the high-strength fiber rod (8) into the isolation cover (9). The fiber rod (8) is located between the model and the jack (10). The jack (10) gives a small pre-pressure to the inner wall of the model so that the fiber rod (8) can be aligned with the direction of the top force when loaded. Step 4: Then install and place the displacement gauge (7) for testing and connect it to the data acquisition device. Finally, fill the remaining sand (2) into the wooden model box (1) until it is flush with the port of the model. After confirming that there are no errors, the loading and recording can be carried out.