A device for detecting the thickness of sediment at the bottom of a cast-in-place concrete pile

Abstract

The application discloses a concrete bored pile bottom sediment thickness detection device, and belongs to the technical field of concrete bored pile construction. The device comprises a measuring rope, a measuring weight, a floating plate arranged below the measuring weight and a connecting frame for connecting the floating plate and the measuring weight. A hole is formed in the middle of the floating plate for the measuring weight to pass through, and a water-soluble film is arranged on the upper surface of the floating plate corresponding to the hole. A gap is formed between the bottom of the measuring weight and the upper surface of the water-soluble film, and the gap is not less than zero. According to the application, an operator lowers the measuring weight into a pile hole, and when the measuring weight is supported on the water-soluble film, the tension of the measuring rope instantaneously decreases, and the measuring rope is pulled upward until it is straight. At this time, the point where the measuring weight contacts the water-soluble film is recorded. Then, water is supplied along the measuring rope to dissolve the water-soluble film, the measuring rope is continuously lowered, and the point where the measuring weight contacts the bottom of the sediment is measured and recorded. The difference between the two points is recorded as a, and a is the sum of the sediment thickness and the thickness of the floating plate. The sediment thickness is a minus the thickness of the floating plate.

Description

Technical Field

[0001] This application relates to a device for detecting the thickness of sediment at the bottom of a concrete cast-in-place pile, belonging to the technical field of concrete bored cast-in-place pile construction. Background Technology

[0002] During the construction of bored cast-in-place concrete piles, the thickness of the sediment at the bottom of the hole affects the structural strength of the pile body later. Therefore, it is necessary to measure the sediment thickness before pouring concrete into the pile. Sediment is the sediment left behind by sedimentation or hole collapse during drilling and cleaning, which is not carried away by the circulating mud. It is generally composed of relatively coarse particles, and the sediment thickness is the height of this sediment layer.

[0003] Currently, the plumb bob method is the most common measurement method on construction sites. Its principle involves using a measuring rope to attach the bottom of a conical plumb bob. The plumb bob is lowered from the pile hole. Because the sediment consists of relatively coarse particles, the operator, based on experience, makes a judgment and records the position on the rope corresponding to the top of the borehole the moment the plumb bob enters the sediment. The plumb bob is then lowered further while being shaken up and down. When the plumb bob completely sinks to the bottom of the hole, the operator records the position on the rope corresponding to the top of the borehole again. The distance between the two records is the sediment thickness.

[0004] However, the subjective nature of recording the moment the measuring hammer enters the sediment based on the operator's experience leads to a large error in the final sediment thickness measurement, which directly affects the subsequent construction strategy.

[0005] To address the aforementioned issues, a device for detecting the thickness of sediment at the bottom of cast-in-place concrete piles is needed. This device can reduce the difficulty of recording the moment the measuring hammer enters the sediment liquid surface, making the recording process more objective and accurate. Summary of the Invention

[0006] The technical problem to be solved by this application is to provide a device for detecting the thickness of sediment at the bottom of concrete cast-in-place piles, which solves the problem of the difficulty in manually judging the contact between the measuring hammer and the sediment liquid surface in the prior art.

[0007] The technical problem to be solved in this application is achieved by the following technical solution:

[0008] A device for detecting the thickness of sediment at the bottom of a cast-in-place concrete pile includes a measuring rope and a measuring hammer; it also includes...

[0009] A float plate is installed below the measuring hammer and has holes for the measuring hammer to pass through.

[0010] A water-soluble film covers the area corresponding to the holes on the upper surface of the float plate; and

[0011] Connecting frame, used to connect the float and the measuring hammer;

[0012] A gap is formed between the bottom of the measuring hammer and the upper surface of the water-soluble film, and the gap is not less than zero.

[0013] Using the above technical solution, the operator lowers the measuring hammer into the pile hole. When the float plate contacts the sediment surface, the operator can feel the measuring rope become lighter, indicating that the measuring hammer is close to the sediment surface. The measuring rope is lowered further until the force on the measuring rope suddenly disappears, indicating that the measuring hammer has fallen onto the water-soluble film. The measuring rope is pulled up until it is taut; this point is the contact point between the measuring hammer and the water-soluble film, and it is recorded. Then, water is supplied along the measuring rope to dissolve the water-soluble film. The measuring rope is lowered further, and the point where the measuring hammer contacts the bottom of the sediment is measured and recorded. The difference between the two points is recorded as 'a', where 'a' is the sum of the sediment thickness and the float plate thickness. The sediment thickness is a minus the float plate thickness.

[0014] This application further specifies that the connecting frame includes:

[0015] A sleeve, fixed to the top of the measuring hammer and fitted onto the outside of the measuring rope; and

[0016] A fixing rope is used to secure the float and the sleeve.

[0017] The length of the sleeve is not less than the thickness of the sediment.

[0018] By adopting the above technical solution, the fixing rope can be prevented from getting tangled on the measuring rope. During the lowering process, the measuring hammer may rotate due to the measuring rope itself or factors such as wind resistance. By fixing the fixing rope to the top of the sleeve, and the sleeve being fitted over the measuring rope, the sleeve can buffer the rotation of the measuring rope, thereby allowing the fixing rope to quickly adjust its position and maintain structural stability.

[0019] This application further specifies that: the connecting frame includes connecting rods, which are arranged perpendicular to the sleeve; at least two connecting rods are provided, and the connecting rods are evenly distributed on the periphery of the top of the sleeve;

[0020] The fixing rope is connected to the cantilever end of the connecting rod and the upper surface of the floating plate; during the lowering of the measuring hammer, the fixing rope is in a vertical state.

[0021] By adopting the above technical solution, the structural stability of the float during the lowering process is further improved. Since the fixing rope is in a vertical state during the lowering process, the fixing rope will not be wrapped around the outside of the measuring rope, and the fixing rope only bears axial tension, which can extend the service life of the fixing rope.

[0022] This application further specifies that a force gauge is provided at the free end of the measuring rope.

[0023] By adopting the above technical solution, when the measuring hammer approaches the sediment, the operator holds the force gauge, lowers the measuring rope, and observes the force gauge. When the value of the force gauge decreases, it indicates that the float has floated on the sediment surface. When the value of the force gauge decreases again, it indicates that the measuring hammer has adhered to the water-soluble film. Judging by the force gauge can provide a more accurate and objective understanding of the state of the measuring hammer, greatly reducing the difficulty of recording.

[0024] This application further specifies that: a displacement measuring mechanism is provided at the free end of the measuring rope.

[0025] By adopting the above technical solution, the distance from when the measuring hammer contacts the aqueous film floating on the surface of the sediment to when the measuring hammer sinks to the bottom of the sediment is directly measured. The thickness of the sediment is obtained by subtracting the thickness of the float plate from the obtained distance. This makes the measurement process more convenient and faster, while reducing the error in the measurement process.

[0026] This application further specifies that the displacement measuring mechanism includes:

[0027] The displacement sensor is positioned directly opposite the measuring rope.

[0028] A display for showing the distance the measuring rope has moved; and

[0029] The cable hanger is positioned on both sides of the displacement sensor.

[0030] By adopting the above technical solution, the setting of the wire auger can keep the measuring rope that needs to be measured horizontal, thereby improving the accuracy of the data captured by the displacement sensor. The display can directly show the distance moved by the measuring rope, which facilitates rapid measurement. The operator does not need to lift the measuring rope and then manually measure the distance between the two recorded points.

[0031] This application further specifies that the measuring rope is wound at least one turn around the stringer away from the pile hole.

[0032] By adopting the above technical solution, the structural stability during the movement of the measuring rope is further improved, thereby improving the accuracy of displacement sensor measurements.

[0033] This application further specifies that a vibrator is mounted on the top of the sleeve.

[0034] By employing the above technical solution, since the sediment consists of relatively coarse particles, when operators manually judge whether the measuring hammer has reached the bottom of the sediment, the hammer may only be contacting larger stones. In this case, moving the hammer by shaking the measuring rope to make it sink is very difficult because the whiplash effect causes a slight shaking of the top of the rope to result in a large shaking of the hammer, which is not conducive to moving the hammer and may even cause the sediment to sink due to the large shaking of the hammer. However, by using a vibrator, the hammer can be shaken at a high frequency and with small amplitude, thereby moving the relative position of the hammer and the stones, allowing the hammer to reach the bottom of the sediment.

[0035] The beneficial effects of this application are as follows: 1. A float plate is set up, and a water-soluble film is covered at the hole in the middle of the float plate. The first point recorded on the measuring rope is obtained by the contact between the measuring hammer and the water-soluble film. The second point is obtained by the measuring hammer below. The difference between the two points is then subtracted from the thickness of the float plate to obtain the sediment thickness. Since the tension at the point where the operator holds the measuring rope decreases instantaneously after the measuring hammer contacts the water-soluble film, the operator can clearly know the point without having to carefully judge based on experience, which greatly improves the objectivity and accuracy of the operation. 2. A force gauge is set up to cooperate with the operator for real-time judgment, which further improves the accuracy. 3. A displacement measuring mechanism is set up to obtain the distance from when the measuring hammer contacts the water-soluble film to when the measuring hammer reaches the bottom of the sediment. The sediment thickness is then obtained directly by subtracting the thickness of the float plate from this distance, without the need to measure the position recorded on the measuring rope later, which is convenient and quick. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the overall structure of Embodiment 1 of this application;

[0037] Figure 2 yes Figure 1 A magnified view of the local structure;

[0038] Figure 3 yes Figure 2 AA cross-section view;

[0039] Figure 4 yes Figure 2 BB cross-section;

[0040] Figure 5 It is a diagram showing the relative positions of the structural float, connecting frame, and measuring hammer after the measuring hammer passes through the water-soluble film;

[0041] Figure 6 This is a schematic diagram of the overall structure of Embodiment 2;

[0042] Figure 7 This is a schematic diagram of the overall structure of Embodiment 3.

[0043] In the diagram: 1. Pile hole; 2. Measuring rope; 21. Force gauge; 3. Measuring hammer; 4. Connecting frame; 41. Sleeve; 42. Connecting rod; 43. Fixing rope; 5. Float; 51. Hole; 52. Water-soluble film; 6. Vibrator; 7. Displacement measuring mechanism; 71. Displacement sensor; 72. Display; 73. Cable loader; 8. Winch. Implementation

[0044] To facilitate a clear understanding of the technical means, creative features, objectives, and effects of this application, the following description, in conjunction with specific illustrations, further elaborates on this application. Example

[0045] like Figure 1 As shown, this application discloses a device for detecting the thickness of sediment at the bottom of a concrete cast-in-place pile, which includes a measuring rope 2, a measuring hammer 3 fixed to one end of the measuring rope 2, a connecting frame 4 fixed to the measuring hammer 3 and connected to one end of the measuring rope 2, and a floating plate 5 connected to the connecting frame 4. The measuring hammer 3 has a conical structure with a larger cross-section. One end is fixed to the measuring rope 2, and the other end is passivated. The diameter of the passivated end face is 2-4 mm.

[0046] Combination Figure 1 and Figure 2 The float plate 5 is positioned directly below the measuring hammer 3, and the float plate 5 has holes 51 through which the measuring hammer 3 can pass. Simultaneously, the length of the connecting frame 4 exceeds the thickness of the sediment, allowing the measuring hammer 3 to pass through the holes 51 and reach the bottom of the sediment. A water-soluble film 52 covers the upper surface of the float plate 5 at the position corresponding to the holes 51, and a gap of not less than zero is formed between the water-soluble film 52 and the bottom end of the measuring hammer 3.

[0047] During the operation, the operator lowers the measuring hammer 3. When the float plate 5 contacts the liquid surface of the sediment, if the gap between the water-soluble film 52 and the measuring hammer 3 is zero, the tension on the measuring rope 2 will decrease sharply as the measuring hammer 3 continues to be lowered. The operator can clearly know that the measuring hammer 3 is blocked by the water-soluble film 52, and thus make a quick judgment.

[0048] Combination Figure 2-4 To improve the structural stability of the float 5 during the descent of the measuring hammer 3, the connecting frame 4 includes a sleeve 41 fixed to the top of the measuring hammer 3, a connecting rod 42 vertically fixed to the top of the sleeve 41, and a fixing rope 43 connecting the connecting rod 42 and the float 5. The sleeve 41 and the measuring hammer 3 are coaxially arranged, and the sleeve 41 is fitted onto the outside of the measuring rope 2. At least two connecting rods 42 are evenly arranged along the circumference of the sleeve 41 to enhance the fixing effect on the float 5. During the descent of the measuring hammer 3, the fixing rope 43 is in a vertical state.

[0049] To more accurately determine the point where the measuring hammer 3 enters the sediment surface, a force gauge 21 is also connected to the free end of the measuring rope 2. When the operator lowers the measuring hammer 3 close to the sediment surface, the force gauge 21 is connected to the free end of the measuring rope 2, and the measuring hammer 3 is slowly lowered while observing the change in the tension value on the force gauge 21. When the tension decreases, it indicates that the float 5 has contacted the sediment surface. When the tension suddenly decreases and approaches zero, it indicates that the measuring hammer 3 has contacted the water-soluble film 52 and the measuring hammer 3 has tilted. At this time, the measuring rope 2 needs to be slowly retrieved to restore the force gauge 21 value, and the point can be recorded. The force gauge 21 needs to maintain a straight line during movement. On the construction site, it can be kept horizontal by using structures such as sliding rails.

[0050] Reference Figure 5 In order to ensure that the measuring hammer 3 can reach the bottom of the sediment completely, a vibrator 6 is installed on the top of the sleeve 41. The vibrator 6 can be a micro vibration motor or other conventional structure. When the measuring hammer 3 is lowered to the point that the measuring rope 2 is loosened, the vibrator 6 is remotely activated to make the measuring hammer 3 vibrate at high frequency, thereby dispersing the stones around the measuring hammer 3.

[0051] The operation process of this application is as follows: First, fix the bracket of the fixed pulley near the pile hole 1 so that the fixed pulley extends above the pile hole 1. Then, place the measuring hammer 3 into the pile hole 1 so that the measuring line moves along the fixed pulley. The measuring hammer 3 is lowered to a position close to the sediment surface. This position is estimated by the depth of the pile hole 1 and the expected sediment depth, and is adjusted according to the actual construction situation. Fix the force gauge 21 to the free end of the measuring rope 2, and keep the force gauge 21 able to move horizontally by using a slide or other equipment. Continue to lower the measuring rope 2. When the reading of the force gauge 21 decreases, the float 5 contacts the sediment surface. Continue to slowly lower the measuring hammer 3 until the reading of the force gauge 21 drops rapidly and the measuring rope 2 suddenly loosens, indicating that the measuring hammer 3 has been supported above the water-soluble film 52. Slowly lift the measuring hammer 3 to make the measuring rope 2 taut and the reading of the force gauge 21 recover. Record the position on the measuring rope 2 corresponding to the top of the pile hole 1 as the first point. Next, water is supplied along the measuring rope 2. The water flows along the rope to the outer wall of the measuring hammer 3 and drips onto the water-soluble film 52. After a short wait, the measuring hammer 3 is lowered further until it passes through the water-soluble film 52 and the reading on the force gauge 21 decreases rapidly again. The vibrator 6 is started to make the measuring hammer 3 vibrate, while the measuring rope 2 is lowered further. The vibrator 6 is turned off after 2-5 minutes. The measuring rope 2 is slowly raised until it is taut and the force gauge 21 returns to its previous value. The position on the measuring rope 2 corresponding to the top of the pile hole 1 is recorded as the second point. The distance between the first and second points is measured and recorded as 'a'. The thickness of the float 5 is recorded as 'h', and the thickness of the sediment is 'ah'. Example

[0052] Reference Figure 6The difference between this application and Embodiment 1 is that a displacement measuring mechanism 7 is provided outside the pile hole 1. The displacement measuring mechanism 7 includes a displacement sensor 71 fixed at the construction site, a display 72 with a signal connected to the displacement sensor 71, and a wire-connecting device 73 erected on both sides of the displacement sensor 71. The wire-connecting device 73 consists of rollers and columns. The measuring line is positioned by the outer wall of the rollers, so that the measuring line measured by the displacement sensor 71 always remains horizontal. To improve the stability of the measuring rope 2, which is the only sensor monitoring part, the measuring rope 2 on the wire-connecting device 73, located away from the pile hole 1, wraps around the roller at least once. When the measuring hammer 3 reaches the first point, the integrated displacement sensor 71 and display 72 are adjusted to the starting point, and the distance a from the measuring hammer 3 to the bottom of the sediment is measured. Example

[0053] Reference Figure 7 The difference between this application and Embodiment 1 is that a winch 8 is used instead of a force gauge 21, and a torque measuring instrument is installed on the winch 8. The change in torque is used to determine the change in tension on the measuring rope 2. The determination method is the same as the tension magnitude in Embodiment 1.

[0054] The foregoing has shown and described the basic principles, main features, and advantages of this application. Those skilled in the art should understand that this application is not limited to the above embodiments, and various changes and modifications can be made without departing from the spirit and scope of this application; all such changes and modifications fall within the scope of protection claimed in this application. The scope of protection of this application is defined by the appended claims and their equivalents.

Claims

1. A device for detecting the thickness of sediment at the bottom of a cast-in-place concrete pile, comprising a measuring rope (2) and a measuring hammer (3); characterized in that: Also includes A float plate (5) is set directly below the measuring hammer (3) and has a hole (51) through which the measuring hammer (3) passes. A water-soluble film (52) covers the area on the upper surface of the float (5) corresponding to the holes (51); as well as Connecting frame (4) is used to connect the float (5) and the measuring hammer (3); A gap is formed between the bottom of the measuring hammer (3) and the upper surface of the water-soluble film (52), and the gap is not less than zero; The connecting frame (4) includes Sleeve (41) is fixed to the top of the measuring hammer (3) and sleeved on the outside of the measuring rope (2); and A fixing rope (43) is fixed between the float (5) and the sleeve (41); The length of the sleeve (41) is not less than the thickness of the sediment.

2. The device for detecting the thickness of sediment at the bottom of a cast-in-place concrete pile according to claim 1, characterized in that: The connecting frame (4) also includes connecting rods (42), which are arranged perpendicular to the sleeve (41); at least two connecting rods (42) are provided, and the connecting rods (42) are evenly distributed on the periphery of the top of the sleeve (41); The fixing rope (43) is connected to the cantilever end of the connecting rod (42) and the upper surface of the float (5); during the process of lowering the measuring hammer (3), the fixing rope (43) is in a vertical state.

3. The device for detecting the thickness of sediment at the bottom of a cast-in-place concrete pile according to claim 1, characterized in that: A force gauge (21) is provided at the free end of the measuring rope (2).

4. The device for detecting the thickness of sediment at the bottom of a cast-in-place concrete pile according to claim 1, characterized in that: The free end of the measuring rope (2) is provided with a displacement measuring mechanism (7).

5. The device for detecting the thickness of sediment at the bottom of a cast-in-place concrete pile according to claim 4, characterized in that: The displacement measuring mechanism (7) includes The displacement sensor (71) is positioned facing the measuring rope (2); Display (72) for displaying the distance traveled by the measuring rope (2); and The cable loader (73) is located on both sides of the displacement sensor (71).

6. The device for detecting the thickness of sediment at the bottom of a cast-in-place concrete pile according to claim 5, characterized in that: The measuring rope (2) is wound at least once on the wire auger (73) away from the pile hole (1).

7. The device for detecting the thickness of sediment at the bottom of a cast-in-place concrete pile according to claim 1, characterized in that: A vibrator (6) is mounted on the top of the sleeve (41).

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