Visual testing device for failure and failure characteristics of tubular pile penetrating through double-layer karst cave

Abstract

The utility model relates to the technical field of civil engineering testing devices, and discloses a visual testing device for failure and failure characteristics of a tubular pile penetrating through a double-layer karst cave, which comprises a reaction frame, a transparent model box, a karst geological simulation layer, an overburden layer, a model pile, a jack, a load sensor, a first vertical displacement sensor, a PIV image processing camera and a monitoring terminal. According to the utility model, the karst geology simulation layer is adopted to carry out model simulation on karst geology. When failure damage characteristics of the model pile are monitored, the jack applies pressure to the pile top of the model pile, the load sensor obtains load data of the model pile and transmits the load data to the monitoring terminal, and the first vertical displacement sensor obtains displacement data of the model pile and transmits the displacement data to the monitoring terminal. And the PIV image processing camera obtains a crack or deformation image of the model pile and transmits the crack or deformation image to the monitoring terminal, so that the failure and damage characteristics of the pipe pile in the underground karst cave are visually and approximately monitored.

Description

TECHNICAL FIELD

[0001] The utility model belongs to civil engineering testing device technical field, especially is involved in a kind of pipe pile failure and destruction characteristic visualization testing device of penetration double-layer karst cave. BACKGROUND

[0002] Karst geology, also known as karst geology, is a common adverse geological phenomenon in the engineering field. Generally, the pile foundation of a building, bridge or road should avoid the karst geological stratum during design. However, the complex and variable karst geological conditions often make it difficult to implement this strategy. In areas with dense underground caves, when the pile foundation cannot completely avoid the caves, it is necessary to use field drilling survey to test the failure and destruction characteristics of the pipe pile. This testing method has high investment cost and cannot directly reflect the failure and destruction characteristics of the pipe pile of the target size in the underground cave. UTILITY MODEL CONTENT

[0003] The utility model provides a kind of pipe pile failure and destruction characteristic visualization testing device of penetration double-layer karst cave, to solve the problems in prior art.

[0004] To achieve the above purpose, the utility model provides the following technical scheme:

[0005] A kind of pipe pile failure and destruction characteristic visualization testing device of penetration double-layer karst cave, including counterforce frame, transparent model box, karst geology simulation layer, soil layer, model pile, jack, load sensor, first vertical displacement sensor, PIV image processing camera and monitoring terminal;

[0006] Wherein, counterforce frame includes base, counterforce column and counterforce beam, counterforce column is vertically arranged and is fixedly connected to base, and the two ends of counterforce beam are fixedly connected to two mutually spaced counterforce columns;Transparent model box is located between two counterforce columns and its bottom surface is abutted to the top surface of base;Karst geology simulation layer is arranged inside transparent model box, and multiple cave simulation grooves vertically layered are formed in karst geology simulation layer;Soil layer is arranged on the top side of karst geology simulation layer;Model pile is embedded into the bottom of karst geology simulation layer after vertically penetrating soil layer and cave simulation groove;The lower base of jack is arranged at the end of model pile exposed from soil layer, and the upper joint of jack is abutted to counterforce beam;Load sensor is arranged between jack and model pile;First vertical displacement sensor is arranged close to model pile and located in cave simulation groove;PIV image processing camera is arranged outside transparent model box, and the lens of PIV image processing camera faces the front of transparent model box;Load sensor, first vertical displacement sensor and PIV image processing camera are communicatively connected to monitoring terminal.

[0007] Through the technical scheme, the device adopts karst geological simulation layer to simulate the karst geology. When the failure and damage characteristics of the monitoring model pile are monitored, the jack applies pressure to the top of the model pile, the load sensor obtains load data of the model pile and transmits the load data to the monitoring terminal, the first vertical displacement sensor obtains displacement data of the model pile and transmits the displacement data to the monitoring terminal, and the PIV image processing camera obtains crack or deformation images of the model pile and transmits the crack or deformation images to the monitoring terminal, so that the failure and damage characteristics of the model pile in the underground karst cave are intuitively and approximately monitored.

[0008] Preferably, the device further comprises a pre-grouting formed frustum, and the frustum is located in the karst simulation groove and the model pile penetrates through the frustum.

[0009] Preferably, the device further comprises strain gauges, and the model pile is hollow inside, and a plurality of strain gauges are vertically and spaced apart arranged in the model pile, and each strain gauge is communicatively connected to the monitoring terminal.

[0010] Preferably, the device further comprises an inductive sheet and an infrared displacement sensor, the inductive sheet is horizontally arranged at an end of the model pile exposed from the soil layer, the inductive end of the infrared displacement sensor faces the inductive sheet, and the infrared displacement sensor is communicatively connected to the monitoring terminal.

[0011] Preferably, the device further comprises an acoustic emission sensor, and the acoustic emission sensor is arranged in the karst geological simulation layer, and the acoustic emission sensor is communicatively connected to the monitoring terminal.

[0012] Preferably, the device further comprises a second vertical displacement sensor, and the second vertical displacement sensor is arranged on the top side of the soil layer, and the second vertical displacement sensor is communicatively connected to the monitoring terminal.

[0013] Preferably, the device further comprises a vertical rod and a horizontal rod, and the end of the vertical rod is fixedly connected to the base, one end of the horizontal rod is fixedly connected to the rod body of the vertical rod, the other end of the horizontal rod penetrates through the outer wall of the transparent model box and the karst geological simulation layer and extends into the karst simulation groove, and the first vertical displacement sensor is fixedly connected to the horizontal rod.

[0014] Preferably, the transparent model box comprises a box body and a front template, and the side of the box body is provided with an opening, and the front template is detachably connected to the edge of the opening.

[0015] The device has the advantages that:

[0016] 1. Compared with the prior art, the device can monitor the failure and damage characteristics of the model pile in the underground karst cave with high simulation degree and intuitively.

[0017] 2. Compared with the prior art, the device can monitor the process and crack development of rock failure and damage (characteristics are top plate punching damage and pile bottom shear damage) through the PIV image processing camera and the acoustic emission sensor.

[0018] 3. Compared with the prior art, the device obtains the axial force borne by the model pile through the strain gauge. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a structural schematic view of the pipe pile failure and damage feature visual testing device for penetrating double-layer karst caves in the embodiment of the utility model.

[0020] Figure 2 is a use state diagram of the pipe pile failure and damage feature visual testing device for penetrating double-layer karst caves in the embodiment of the utility model.

[0021] BRIEF DESCRIPTION OF DRAWINGS

[0022] 1, counterforce frame; 11, base; 12, counterforce column; 13, counterforce beam; 2, transparent model box; 3, karst geological simulation layer; 31, karst cave simulation groove; 32, cone table; 4, soil cover layer; 5, model pile; 6, jack; 7, load sensor; 8, first vertical displacement sensor; 9, PIV image processing camera; 100, monitoring terminal; 200, strain gauge; 300, inductive sheet; 301, infrared displacement sensor; 400, acoustic emission sensor; 500, second vertical displacement sensor; 600, vertical rod; 601, horizontal rod. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the utility model.

[0024] In the description of the utility model, it should be explained that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the utility model.

[0025] Referring to Figure 1 and Figure 2 , the embodiment discloses a pipe pile failure and damage feature visual testing device for penetrating double-layer karst caves, which comprises a counterforce frame 1, a transparent model box 2, a karst geological simulation layer 3, a soil cover layer 4, a model pile 5, a jack 6, a load sensor 7, a first vertical displacement sensor 8, a PIV image processing camera 9 and a monitoring terminal 100.

[0026] Specifically, the counterforce frame 1 is used as a support and counterforce component, which comprises a base 11, two mutually spaced counterforce columns 12 and a counterforce beam 13. The counterforce columns 12 are vertically arranged and fixedly connected to the base 11, and the two ends of the counterforce beam 13 are fixedly connected to the two counterforce columns 12. In the embodiment, the transparent model box 2 is made of acrylic plate, which is arranged between the two counterforce columns 12 and abuts against the top surface of the base 11. The karst geological simulation layer 3 is a similar scaled model of the underground karst geological layer, which is arranged inside the transparent model box 2 and internally provided with a plurality of vertically layered cave simulation grooves 31. The soil cover layer 4 is arranged on the top side of the karst geological simulation layer 3. The model pile 5 penetrates the soil cover layer 4 and the cave simulation groove 31 vertically and is embedded into the bottom of the karst geological simulation layer 3. The jack 6 is used to apply load to the model pile 5, and the lower base 11 of the jack 6 is arranged at the end of the model pile 5 exposed from the soil cover layer 4, and the upper joint abuts against the counterforce beam 13. The load sensor 7 is used to monitor the load borne by the end of the model pile 5 and is arranged between the jack 6 and the model pile 5. The first vertical displacement sensor 8 is arranged close to the model pile 5 and located in the cave simulation groove 31, and is used to monitor the displacement or deformation of the model pile 5 when bearing load. The PIV image processing camera 9 is used to acquire image information of the model pile 5 in real time, which is arranged outside the transparent model box 2, and the lens of the PIV image processing camera 9 faces the front surface of the transparent model box 2. The load sensor 7, the first vertical displacement sensor 8 and the PIV image processing camera 9 are communicatively connected to the monitoring terminal 100.

[0027] Through the above technical scheme, the device of the utility model adopts the karst geological simulation layer 3 to model simulate the karst geology. When monitoring the failure and damage characteristics of the model pile 5, the jack 6 applies pressure to the top of the model pile 5, the load sensor 7 acquires load data of the model pile 5 and transmits the load data to the monitoring terminal 100, the first vertical displacement sensor 8 acquires displacement data of the model pile 5 and transmits the displacement data to the monitoring terminal 100, and the PIV image processing camera 9 acquires crack or deformation images of the model pile 5 and transmits the images to the monitoring terminal, so that the failure and damage characteristics of the model pile in the underground cave are intuitively and approximately monitored.

[0028] Further, after the karst geological simulation layer 3 is placed in the above transparent model box 2, the karst geological simulation layer 3 needs to be punched and injected with concrete slurry, and after solidification, a frustum 32 is formed in the cave simulation groove 31 to simulate stalactite or stalagmite structure in the cave, thereby improving the simulation degree of the karst geological simulation layer 3.

[0029] Further, the device further comprises an inductive sheet 300 and an infrared displacement sensor 301, in the embodiment, the inductive sheet 300 can be selected from a steel sheet, the inductive sheet 300 is arranged at the end of the model pile 5 exposed to the soil layer 4, the inductive end of the infrared displacement sensor 301 faces the inductive sheet 300, and the infrared displacement sensor 301 is communicatively connected to the monitoring terminal 100.

[0030] It should be noted that the infrared displacement sensor 301 can obtain displacement data of the model pile 5 in the upward and downward or horizontal directions and transmit the displacement data to the monitoring terminal 100, and the load sensor 7 transmits the pile head load data to the monitoring terminal 100. Therefore, by the above technical solution, the monitoring terminal 100 can obtain the load-displacement curve and the quantitative characterization data of the failure body.

[0031] Further, the device further comprises an acoustic emission sensor 400 arranged in the karst geological simulation layer 3.

[0032] Through the above technical solution, the acoustic emission sensor 400 is mainly used for monitoring cracks in the karst geological simulation layer 3, and can visually monitor the process of rock failure (characterized by roof punching failure and pile bottom shear failure) and crack development.

[0033] Preferably, the acoustic emission sensor 400 is provided with a plurality of acoustic emission sensors 400 distributed around the cave simulation groove 31.

[0034] Further, the device further comprises a second vertical displacement sensor 500 arranged at the top side of the soil layer 4, and the second vertical displacement sensor 500 is communicatively connected to the monitoring terminal 100.

[0035] Through the above technical solution, the accuracy of the displacement monitoring of the model pile 5 can be improved.

[0036] Preferably, in order to fix the first vertical displacement sensor 8 and the second vertical displacement sensor 500, the device further comprises a vertical rod 600 and a horizontal rod 601. One end of one of the horizontal rods 601 is fixedly connected to the rod body of the vertical rod 600, and the other end penetrates the outer wall of the transparent model box 2 and the karst geological simulation layer 3 and extends into the cave simulation groove 31, and the first vertical displacement sensor 8 is fixedly connected to the horizontal rod 601. As for the fixing connection mode of the second vertical displacement sensor 500, the connection mode of the first vertical displacement sensor 8 is similar, and details are not repeated here.

[0037] Preferably, the transparent model box 2 comprises a box body and a front panel (not shown in the drawing), and the side of the box body is provided with an opening, and the front panel is detachably connected to the edge of the opening.

[0038] The working principle of the embodiment of the utility model is:

[0039] First, let the jack 6 apply load to the pile top of the model pile 5, and then through the PIV image processing system and the acoustic emission sensor 400, the process and crack development of rock failure and damage (characterized by punching damage of the cave roof and shear damage of the pile bottom) are visually monitored. At the same time, the deformation of the cave roof and the deformation of the overlying soil sample are obtained through the first vertical displacement sensor 8, and the load-displacement curve and the quantitative characterization data of the failure body are obtained through the infrared displacement sensor 301, and the axial force of the pile body is obtained through the strain gauge 200.

[0040] The above are preferred embodiments of the utility model, and do not limit the protection scope of the utility model, so that: equivalent changes made according to the structure, shape and principle of the utility model should be covered within the protection scope of the utility model.

Claims

1. A device for visualizing failure and damage characteristics of a pipe pile penetrating a double-layered solution cavity, characterized in that, The karst geology simulation device comprises a counterforce frame (1), a transparent model box (2), a karst geology simulation layer (3), a soil layer (4), a model pile (5), a jack (6), a load sensor (7), a first vertical displacement sensor (8), a PIV image processing camera (9) and a monitoring terminal (100). The counterforce frame (1) comprises a base (11), counterforce columns (12) and a counterforce beam (13), the counterforce columns (12) are vertically arranged and fixedly connected to the base (11), and the two ends of the counterforce beam (13) are fixedly connected to two counterforce columns (12) which are spaced apart from each other; the transparent model box (2) is located between the two counterforce columns (12) and the bottom surface thereof abuts against the top surface of the base (11); the karst geology simulation layer (3) is arranged inside the transparent model box (2), and a plurality of vertically layered karst cave simulation grooves (31) are formed in the karst geology simulation layer (3); the soil layer (4) is arranged on the top side of the karst geology simulation layer (3); the model pile (5) penetrates the soil layer (4) and the karst cave simulation groove (31) vertically and is embedded into the bottom of the karst geology simulation layer (3); the lower base (11) of the jack (6) is arranged at the end of the model pile (5) which is exposed from the soil layer (4), and the upper joint of the jack (6) abuts against the counterforce beam (13); the load sensor (7) is arranged between the jack (6) and the model pile (5); the first vertical displacement sensor (8) is arranged close to the model pile (5) and located in the karst cave simulation groove (31); the PIV image processing camera (9) is arranged outside the transparent model box (2), and the lens of the PIV image processing camera (9) faces the front of the transparent model box (2); the load sensor (7), the first vertical displacement sensor (8) and the PIV image processing camera (9) are communicatively connected to the monitoring terminal (100).

2. The device for visualizing the failure and destruction features of a pipe pile penetrating a double-layer karst cave according to claim 1, characterized in that, The device further comprises a pre-grouting conical frustum (32), which is located in the karst cave simulation groove (31) and is penetrated by the model pile (5).

3. The device for visualizing failure and destruction features of a pipe pile penetrating a double-layered cavity according to claim 1, characterized in that, The device further comprises strain gauges (200), the model pile (5) is hollow, and a plurality of strain gauges (200) are vertically and spaced apart arranged in the model pile (5), and each strain gauge (200) is communicatively connected to the monitoring terminal (100).

4. The device for visualizing the failure and destruction features of a pipe pile penetrating a double-layer karst cave according to claim 1, characterized in that, The device further comprises an inductive sheet (300) and an infrared displacement sensor (301), the inductive sheet (300) is horizontally arranged at the end of the model pile (5) which is exposed from the soil layer (4), the inductive end of the infrared displacement sensor (301) faces the inductive sheet (300), and the infrared displacement sensor (301) is communicatively connected to the monitoring terminal (100).

5. The device for visualizing the failure and destruction features of a pipe pile penetrating a double-layered cavity according to claim 1, characterized in that, The device further comprises an acoustic emission sensor (400), which is arranged in the karst geology simulation layer (3), and the acoustic emission sensor (400) is communicatively connected to the monitoring terminal (100).

6. The device for visualizing the failure and destruction features of a pipe pile penetrating a double-layered cavity according to claim 1, characterized in that, The second vertical displacement sensor (500) is arranged on the top side of the mulch layer (4), and is in communication connection with the monitoring terminal (100).

7. The device for visualizing the failure and destruction features of a pipe pile penetrating a double-layered cavity according to claim 1, characterized in that, The vertical rod (600) is fixedly connected at the end to the base (11), and the horizontal rod (601) is fixedly connected at one end to the rod body of the vertical rod (600) and at the other end to the transparent model box (2) and the karst geological simulation layer (3) and then extends into the cave simulation groove (31), and the first vertical displacement sensor (8) is fixedly connected to the horizontal rod (601).

8. The device for visualizing the failure and destruction features of a pipe pile penetrating a double-layered cavity according to claim 1, characterized in that, The transparent model box (2) comprises a box body and a front template, the side of the box body is provided with an opening, and the front template is detachably connected to the edge of the opening.

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