A bearing capacity testing device for bridge construction in an expansive soil area

Abstract

The application discloses a bearing capacity testing device for bridge construction in an expansive soil area and relates to the field of bridge construction, which comprises a frame base, a driving mechanism is arranged to slide along the vertical direction of the frame base, punching mechanisms are symmetrically arranged to rotate on the two sides of the driving mechanism, water supply mechanisms for controlling water inflow and penetration mechanisms for controlling soil layer beating are arranged on the top of the frame base respectively, the driving mechanism driving device synchronously controls the rotation and vertical lifting movement of two rotating rods, two initial state testing boreholes are formed at adjacent positions, one valve on the water distribution box is opened, water is injected into the corresponding rotating rod, active humidification of the expansive soil body around one side of the testing hole is realized, high humidity working conditions are simulated, in-situ, rapid and quantitative humidity and bearing capacity sensitivity analysis of the expansive soil area is realized through double-hole synchronous hole forming and single-hole active humidification, and the key defects that the traditional testing method cannot simulate humidity change and lacks in-situ synchronous comparison are effectively solved.

Description

Technical Field

[0001] This invention relates to the field of bridge construction equipment, and more particularly to a bearing capacity testing device for expansive soil areas based on bridge construction. Background Technology

[0002] Accurately assessing the bearing capacity of the foundation is a key challenge in ensuring the safety and stability of structures when constructing bridges and other engineering projects in expansive soil areas. Expansive soil has significant characteristics of swelling upon water absorption and shrinking upon water loss, and its bearing capacity is extremely sensitive to changes in water content. Therefore, testing the bearing capacity under natural conditions is far from sufficient. It is necessary to understand the variation law of bearing capacity under different humidity conditions in order to provide a reliable basis for foundation treatment design and long-term safe operation.

[0003] Currently, the main method for conducting on-site bearing capacity testing in expansive soil areas is the standard penetration test / dynamic cone penetration test. The principle is to use a standard hammer and drop height to drive the penetrator (or cone probe) into the soil, record the number of hammer blows required to penetrate to a certain depth, and indirectly estimate the bearing capacity, density, etc. of the soil layer.

[0004] However, this method usually only reflects the soil properties under the current natural state at the test point, and cannot actively change or compare the changes in bearing capacity under different humidity conditions. Summary of the Invention

[0005] The purpose of this invention is to provide a bearing capacity testing device for expansive soil areas based on bridge construction, in order to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a bearing capacity testing device for expansive soil areas based on bridge construction, including a frame, a driving mechanism that is slidably arranged along the vertical direction of the frame, a drilling mechanism that is symmetrically rotated on both sides of the driving mechanism, and a water supply mechanism for controlling water inlet and a penetration mechanism for controlling the impact on the soil layer respectively arranged on the top of the frame.

[0007] The drilling mechanism includes two rotating rods that rotate on both sides of the drive mechanism, and the penetration mechanism includes two drill rods that slide on the inner sides of the two rotating rods respectively, and a winding reel that is rotatably installed on the top of the frame to control the lifting and lowering of the two drill rods.

[0008] The water supply mechanism includes a water distribution box fixedly installed on the top of the frame, and two rotating sleeves rotatably connected to the outside of two rotating rods. The two rotating sleeves are connected to the water distribution box, and the water distribution box is equipped with two valves for controlling the water supply to the two rotating sleeves.

[0009] As a further description of the above technical solution: the frame includes several horizontal frames aligned in parallel and several guide rods arranged in a rectangular array between the horizontal frames. A top plate is fixedly connected between the two uppermost horizontal frames, and two connecting blocks are fixedly connected to the two frontmost horizontal frames respectively. A lead screw is fixedly connected between the two connecting blocks.

[0010] As a further description of the above technical solution: the driving mechanism includes two parallel and symmetrically fixed frames, which are slidably connected to the outside of several guide rods. A servo motor is fixedly installed at the bottom center of the lowest frame. The output shaft of the servo motor is fixedly connected to a drive rod through a coupling. A double-groove pulley is fixedly connected to the lower side of the outer surface of the drive rod. Two single-groove pulleys are fixedly connected to the upper side of the outer surface of the two rotating rods respectively. The two single-groove pulleys are connected to the double-groove pulleys through two belt drives.

[0011] As a further description of the above technical solution: a connecting sleeve is fixedly connected to the rear side of the top center of the bottommost frame, a threaded nut is rotatably connected to the top of the connecting sleeve, the inner side of the threaded nut is threadedly connected to the outer side of the lead screw, a gear is fixedly connected to the upper side of the outer surface of the drive rod, and a gear disk that meshes with the gear is fixedly connected to the outer side of the threaded nut.

[0012] As a further description of the above technical solution: both rotating rods are fixedly connected to the bottom ends of the two rotating rods, and both rotating rods are coaxially fixedly connected to the outer sides of the two rotating rods. The inner cavities of the two rotating rods and the two rotating rods are connected, and both the upper and lower ends are open.

[0013] As a further description of the above technical solution: the water distribution box is fixedly installed on the top of the top plate, the two rotating sleeves are respectively rotatably sleeved on the top of the two rotating rods, the top ends of the two rotating sleeves are fixedly connected to the bottom end of the uppermost frame, the two rotating sleeves are connected to the water distribution box through two connecting pipes, and the top of the water distribution box is connected to the output end of the external water pump through a water supply pipe.

[0014] As a further description of the above technical solution: both of the chisels have swivel grooves on their outer surfaces, both chisels have hammers fixedly connected to their bottom ends, both chisels have their top ends penetrating the top ends of the two rotating sleeves and extending upwards, and both chisels have connecting rings fixedly connected to their top ends.

[0015] As a further description of the above technical solution: the penetration mechanism also includes a second servo motor fixedly installed on the top of the top plate, and two wheel seats alternately installed on both sides of the top of the top plate. The top of each of the two wheel seats is rotatably connected to a guide wheel. The output shaft of the second servo motor is coaxially and fixedly connected to the take-up reel. The pull ropes in the two take-up areas on the take-up reel are respectively bound to two connecting rings, and the two pull ropes are respectively guided by two guide wheels.

[0016] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0017] The drive mechanism synchronously controls the rotation and vertical lifting of two rotating rods, forming two initial test wells at adjacent positions. Opening one valve on the water distribution box injects water into the corresponding rotating rod, actively humidifying the expansive soil surrounding one test well and simulating high humidity conditions. Using two drill rods slidably connected within the two rotating rods, the two test wells are synchronously and repeatedly hammered under the same standard. The penetration depth or settlement difference between the two drill rods under the same number of blows or the same energy input is measured and compared. This allows for in-situ and quantitative determination of the immediate impact of different humidity levels on the bearing capacity of expansive soil. This invention, through synchronous drilling with two holes, active humidification of a single hole, synchronous hammering with the same parameters, and comparative penetration tests, achieves in-situ, rapid, and quantitative analysis of humidity and bearing capacity sensitivity in expansive soil areas. It effectively solves the key shortcomings of traditional testing methods, such as the inability to simulate humidity changes and the lack of in-situ synchronous control. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall side elevation structure of the present invention;

[0019] Figure 2 This is a schematic diagram of the side elevation structure of the frame in this invention;

[0020] Figure 3 This is a schematic diagram of the disassembled structure of the drive mechanism in this invention;

[0021] Figure 4 For the present invention Figure 2 Enlarged view of node A in the middle;

[0022] Figure 5 For the present invention Figure 2 Enlarged schematic diagram of a local cross-sectional node at point B;

[0023] Figure 6 This is a schematic diagram of the lower split structure of the rotating rod and the chisel rod in this invention;

[0024] Figure 7 This is a schematic diagram of the connection structure between the top plate, the penetration mechanism and the water supply mechanism of the present invention.

[0025] Legend:

[0026] 1. Frame base; 11. Horizontal frame; 12. Guide rod; 13. Top plate; 14. Connecting block; 15. Screw rod;

[0027] 2. Drive mechanism; 21. Frame; 22. Servo motor 1; 221. Drive rod; 222. Double groove pulley; 223. Gear; 23. Connecting sleeve; 231. Thread nut disc; 232. Gear disc; 24. Single groove pulley;

[0028] 3. Drilling mechanism; 31. Rotating rod; 32. Retractor blade; 33. Drill bit;

[0029] 4. Penetration mechanism; 41. Servo motor II; 42. Rewind reel; 43. Wheel seat; 431. Guide wheel; 44. Chisel; 441. Connecting ring; 442. Rotary groove; 443. Hammer head;

[0030] 5. Water supply mechanism; 51. Water distribution box; 511. Water supply pipe; 512. Valve; 513. Connecting pipe; 52. Rotating sleeve. Detailed Implementation

[0031] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] like Figure 1 - Figure 7 As shown, the present invention provides a bearing capacity testing device for expansive soil areas based on bridge construction, including a frame 1, a driving mechanism 2 slidably arranged along the vertical direction of the frame 1, and a drilling mechanism 3 symmetrically rotated on both sides of the driving mechanism 2.

[0033] The top of the frame 1 is respectively equipped with a water supply mechanism 5 for controlling water inlet and a penetration mechanism 4 for controlling the impact of soil layers. The drilling mechanism 3 includes two rotating rods 31 that rotate on both sides of the drive mechanism 2. The penetration mechanism 4 includes two drill rods 44 that slide on the inner side of the two rotating rods 31 respectively, and a winding reel 42 that is rotatably installed on the top of the frame 1 to control the lifting and lowering of the two drill rods 44. The water supply mechanism 5 includes a water distribution box 51 that is fixedly installed on the top of the frame 1, and two rotating sleeves 52 that are rotatably connected to the outer side of the two rotating rods 31. The two rotating sleeves 52 are connected to the water distribution box 51, and two valves 512 that control the water supply to the two rotating sleeves 52 are respectively installed on the water distribution box 51.

[0034] In practical use, this scheme uses the drive mechanism 2 to synchronously control the rotation and vertical lifting of two rotating rods 31, forming two initial test wells at adjacent positions. One of the valves 512 on the water distribution box 51 is opened to inject water into the corresponding rotating rod 31, thereby actively humidifying the expansive soil around one side of the test well and simulating high humidity conditions. Using two drill rods 44 slidably connected inside the two rotating rods 31, the two test wells are synchronously and repeatedly hammered with the same hammer weight, drop distance, and hitting frequency. The difference in penetration or settlement of the two drill rods 44 under the same number of hits or the same energy input is measured and compared, so that the immediate impact of different humidity conditions on the bearing capacity of expansive soil can be obtained in situ and quantitatively.

[0035] Specifically, such as Figures 1-6 As shown, the frame 1 includes several horizontal frames 11 aligned in parallel and several guide rods 12 arranged in a rectangular array between the horizontal frames 11. A top plate 13 is fixedly connected between the two uppermost horizontal frames 11. Two connecting blocks 14 are fixedly connected to the two frontmost horizontal frames 11 respectively. A lead screw 15 is fixedly connected between the two connecting blocks 14.

[0036] The drive mechanism 2 includes two parallel and symmetrically fixed frames 21. The two frames 21 are slidably connected to the outside of several guide rods 12. A servo motor 22 is fixedly installed at the bottom center of the lowest frame 21. The output shaft of the servo motor 22 is fixedly connected to a drive rod 221 through a coupling. A double-groove pulley 222 is fixedly connected to the lower side of the outer surface of the drive rod 221. Two single-groove pulleys 24 are fixedly connected to the upper side of the outer surface of the two rotating rods 31 respectively. The two single-groove pulleys 24 and the double-groove pulley 222 are connected by two belt drives.

[0037] When constructing bridges, bridges are usually erected on the ground by installing pile foundations. Therefore, when testing expansive soil in the test area, it is necessary to first drill holes according to the depth of the piles.

[0038] Start the servo motor 22. The servo motor 22 drives the drive rod 221 to rotate. The double groove pulley 222 on the outside of the drive rod 221 is connected to the two single groove pulleys 24 on the outside of the two rotating rods 31 through belt drive. In this way, when the drive rod 221 rotates, it drives the two rotating rods 31 to rotate together to drill a hole in the ground.

[0039] Furthermore, a connecting sleeve 23 is fixedly connected to the rear side of the top middle of the bottom frame 21. A threaded nut 231 is rotatably connected to the top of the connecting sleeve 23. The inner side of the threaded nut 231 is threadedly connected to the outer side of the lead screw 15. A gear 223 is fixedly connected to the upper side of the outer surface of the drive rod 221. A gear disk 232 that meshes with the gear 223 is fixedly connected to the outer side of the threaded nut 231.

[0040] When the drive rod 221 rotates forward, it rotates together with the gear 223 and the gear disk 232. The gear disk 232 drives the screw nut disk 231, which is threaded on the outer surface of the screw 15, to rotate. This causes the frame 21 to slide downward along the vertical direction of the screw 15 and several guide rods 12, so that when the two rotating rods 31 rotate, they have a downward pushing force to drill holes in the ground.

[0041] Furthermore, drill bits 33 are fixedly connected to the bottom ends of both rotating rods 31, and auger blades 32 are fixedly connected to the outer sides of both rotating rods 31 on the same axis. The inner cavities of the two rotating rods 31 and the two auger blades 32 are connected, and both the upper and lower ends are open.

[0042] When the rotating rod 31 rotates, it first drills the ground through the drill bit 33 and then transports the soil outward through the blade 32.

[0043] Specifically, such as Figure 4 and Figure 7 As shown, the water distribution box 51 is fixedly installed on the top of the top plate 13. Two rotating sleeves 52 are respectively rotatably sleeved on the top of the two rotating rods 31. The tops of the two rotating sleeves 52 are fixedly connected to the bottom of the uppermost frame 21. The two rotating sleeves 52 and the water distribution box 51 are connected through two connecting pipes 513. The top of the water distribution box 51 is connected to the output end of the external water supply pump through the water inlet pipe 511.

[0044] Water is supplied to the water distribution box 51 by a water pump. When the valve 512 on one side is turned on, the water in the water distribution box 51 flows to the rotating sleeve 52 on the same side through the connecting pipe 513 on the same side. The water in the rotating sleeve 52 flows down into the well hole on the same side through the vortex 442 on the outside of the drill rod 44 to humidify the well hole.

[0045] Specifically, such as Figure 5 - Figure 7 As shown, both chisels 442 are provided on the outer surface of the two chisels 44, and hammers 443 are fixedly connected to the bottom of both chisels 44. The tops of both chisels 44 pass through the tops of the two rotating sleeves 52 and extend upwards. Connecting rings 441 are fixedly connected to the tops of both chisels 44.

[0046] The penetration mechanism 4 also includes a second servo motor 41 fixedly installed at the top of the top plate 13, and two wheel seats 43 alternately installed on both sides of the top of the top plate 13. The top of each wheel seat 43 is rotatably connected to a guide wheel 431. The output shaft of the second servo motor 41 is coaxially and fixedly connected to the take-up reel 42. The pull ropes in the two take-up areas on the take-up reel 42 are respectively bound to two connecting rings 441, and the two pull ropes are respectively guided by two guide wheels 431.

[0047] After humidifying one side of the well hole through the water supply mechanism 5, the two rotating rods 31 are connected to the two chisels 44 and reset and stretched to the upper end of the well hole through the drive mechanism 2. The servo motor 41 is started, and the output shaft of the servo motor 41 drives the winding reel 42 to rotate to the right to unwind the tension in the two areas on the winding reel 42. After unwinding, the two chisels 44 fall naturally due to their own weight, connected to the hammers 443 at their bottom ends, to hammer the expansive soil in the well hole. The servo motor 41 is started again, and the output shaft of the servo motor 41 drives the winding reel 42 to rotate to the left to wind up. This rope winding causes the two servo motors 41 to reset again. This process is repeated so that the two servo motors 41 repeatedly hammer the well hole. After the hammering is completed, the drop at the top of the two servo motors 41 is observed to obtain the difference in the sinking of the two well holes.

[0048] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A bearing capacity testing device for expansive soil areas based on bridge construction, comprising a frame (1), characterized in that: A driving mechanism (2) is slidably arranged along the vertical direction of the frame (1). A drilling mechanism (3) is symmetrically arranged on both sides of the driving mechanism (2). A water supply mechanism (5) for controlling water inlet and a penetration mechanism (4) for controlling the impact on the soil layer are respectively arranged on the top of the frame (1). The drilling mechanism (3) includes two rotating rods (31) rotating on both sides of the drive mechanism (2), and the penetration mechanism (4) includes two drill rods (44) sliding on the inner sides of the two rotating rods (31) respectively, and a winding reel (42) rotatably mounted on the top of the frame (1) to control the lifting and lowering of the two drill rods (44). The water supply mechanism (5) includes a water distribution box (51) fixedly installed on the top of the frame (1), and two rotating sleeves (52) rotatably connected to the outside of the two rotating rods (31). The two rotating sleeves (52) are connected to the water distribution box (51), and two valves (512) for controlling the water supply to the two rotating sleeves (52) are respectively installed on the water distribution box (51).

2. The bearing capacity testing device for expansive soil areas based on bridge construction according to claim 1, characterized in that, The frame (1) includes several horizontal frames (11) aligned in parallel and several guide rods (12) arranged in a rectangular array between the horizontal frames (11). A top plate (13) is fixedly connected between the two uppermost horizontal frames (11), and two connecting blocks (14) are fixedly connected to the two frontmost horizontal frames (11). A lead screw (15) is fixedly connected between the two connecting blocks (14).

3. The bearing capacity testing device for expansive soil areas based on bridge construction according to claim 2, characterized in that, The drive mechanism (2) includes two parallel and symmetrical fixed frames (21). The two frames (21) are slidably connected to the outside of several guide rods (12). A servo motor (22) is fixedly installed at the bottom center of the lowest frame (21). The output shaft of the servo motor (22) is fixedly connected to a drive rod (221) through a coupling. A double groove pulley (222) is fixedly connected to the lower side of the outer surface of the drive rod (221). Two single groove pulleys (24) are fixedly connected to the upper side of the outer surface of the two rotating rods (31). The two single groove pulleys (24) and the double groove pulleys (222) are connected by two belt drives.

4. The bearing capacity testing device for expansive soil areas based on bridge construction according to claim 3, characterized in that, A connecting sleeve (23) is fixedly connected to the rear side of the top center of the bottom frame (21). A thread nut disc (231) is rotatably connected to the top of the connecting sleeve (23). The inner side of the thread nut disc (231) is threadedly connected to the outer side of the lead screw (15). A gear (223) is fixedly connected to the upper side of the outer surface of the drive rod (221). A gear disc (232) that meshes with the gear (223) is fixedly connected to the outer side of the thread nut disc (231).

5. The bearing capacity testing device for expansive soil areas based on bridge construction according to claim 3, characterized in that, Both rotating rods (31) are fixedly connected to the bottom end of the drill bit (33), and both rotating rods (31) are fixedly connected to the outer side of the two rotating rods (31) on the same axis. The two rotating rods (31) are connected to the inner cavity of the two rotating rods (32), and both the upper and lower ends are open.

6. The bearing capacity testing device for expansive soil areas based on bridge construction according to claim 5, characterized in that, The water distribution box (51) is fixedly installed on the top of the top plate (13). The two rotating sleeves (52) are respectively rotatably sleeved on the top of the two rotating rods (31). The tops of the two rotating sleeves (52) are fixedly connected to the bottom of the uppermost frame (21). The two rotating sleeves (52) and the water distribution box (51) are connected through two connecting pipes (513). The top of the water distribution box (51) is connected to the output end of the external water pump through the water supply pipe (511).

7. The bearing capacity testing device for expansive soil areas based on bridge construction according to claim 6, characterized in that, Both of the two drill rods (44) have a swivel groove (442) on their outer surface. Both of the two drill rods (44) have a hammer head (443) fixedly connected to their bottom ends. Both of the two drill rods (44) have their top ends passing through the top ends of the two rotating sleeves (52) and extending upwards. Both of the two drill rods (44) have a connecting ring (441) fixedly connected to their top ends.

8. The bearing capacity testing device for expansive soil areas based on bridge construction according to claim 7, characterized in that, The penetration mechanism (4) also includes a servo motor (41) fixedly installed on the top of the top plate (13) and two wheel seats (43) alternately installed on both sides of the top of the top of the top plate (13). The top of each of the two wheel seats (43) is rotatably connected to a guide wheel (431). The output shaft of the servo motor (41) is coaxially and fixedly connected to the winding reel (42). The pull ropes in the two winding areas on the winding reel (42) are respectively bound to two connecting rings (441), and the two pull ropes are respectively guided by two guide wheels (431).

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