Five-stage slurry preparation system

Abstract

The utility model provides a silt and silt geologic pile foundation rotary digging hole forming five-stage slurry box configuration system which comprises a first-stage settling box, a second-stage settling box, a third-stage settling box, a fourth-stage slurry making box and a five-stage slurry storage box, and the first-stage settling box is used for receiving slurry obtained after pile foundation hole cleaning; the second-stage settling tank is communicated with the downstream of the first-stage settling tank and is used for receiving slurry settled by the first-stage settling tank; the third-stage settling tank is communicated with the downstream of the second-stage settling tank and is used for receiving slurry settled by the second-stage settling tank; the fourth-stage pulping box is communicated with the downstream of the third-stage settling box, is used for receiving the slurry settled by the third-stage settling box, and is provided with a stirring device for mixing the slurry; the fifth-stage slurry storage box is arranged on the downstream portion of the fourth-stage slurry preparation box in a communicating mode and used for storing the slurry obtained after slurry mixing of the fourth-stage slurry preparation box and sending the slurry into a drill hole.

Description

Technical Field

[0001] The utility model relates to the technical field of pile foundation construction of bridge engineering, in particular to a mud system for drilling and grouting piles in poor silt and sand geological conditions and for forming holes with a rotary drilling rig. Background Art

[0002] The rotary drilling rig has become the main drilling equipment for bored pile construction due to its advantages of fast construction speed, good hole quality, low environmental pollution, flexible and convenient operation, high safety performance and strong applicability. The principle of rotary drilling is that under the condition of mud wall protection, the turntable or power head on the rotary drilling rig drives the retractable drill rod and the drill bit at the bottom of the drill rod to rotate, and the cutting tools on the bottom and side opening of the drill bucket are used to cut the rock and soil. At the same time, the cut slag enters the drill bucket from the opening. After the drill bucket is filled with drill cuttings, the drill bit is lifted to the hole mouth through the telescopic drill rod, the bottom is automatically opened to unload the soil, and then the drill bucket is lowered to the bottom of the hole to continue drilling. This is repeated until the designed hole depth is drilled. Therefore, when the drill bit is lifted when the bucket is full of drill rods, a certain suction force will be generated on the hole wall, which is not conducive to the stability of the hole wall. Especially when drilling in poor strata such as silt and silt sand, it is very easy to produce shrinkage and hole collapse. Utility Model Content

[0003] Aiming at the quality accidents or pile body defects such as shrinkage, collapse or sedimentation that are prone to occur in pile foundation construction in plastic geological conditions such as silt sand, silty silty clay and silty clay, a five-level mud box configuration system is proposed to improve the mud recycling process, so as to achieve efficient use of drilling mud slurry, improve mud performance indicators, and enhance the wall protection and hole cleaning effects of rotary drilling, thereby ensuring the quality of pile foundation construction.

[0004] The five-stage mud box configuration system for rotary drilling of silt and silt geological pile foundation provided in this embodiment includes:

[0005] The first-level sedimentation tank is used to receive the mud after the pile foundation is cleaned;

[0006] A secondary sedimentation tank is connected and arranged downstream of the primary sedimentation tank, and is used to receive the sludge settled in the primary sedimentation tank;

[0007] A third-stage sedimentation tank, which is connected and arranged downstream of the second-stage sedimentation tank and is used to receive the sludge settled in the second-stage sedimentation tank;

[0008] A fourth-stage pulping box, which is connected and arranged downstream of the third-stage sedimentation box, and is used to receive the slurry settled in the third-stage sedimentation box. The fourth-stage pulping box is equipped with a stirring device for slurry adjustment;

[0009] The fifth-stage slurry storage box is connected and arranged downstream of the fourth-stage slurry making box. It is used to store the slurry prepared by the fourth-stage slurry making box and send the slurry into the borehole.

[0010] In some embodiments, a plurality of sunken conical sedimentation tanks are provided at the bottom of the primary sedimentation tank.

[0011] In some embodiments, a three-stage vertical filter screen for filtering mud is provided in the secondary sedimentation tank, on which a secondary sedimentation tank slurry inlet and a secondary sedimentation tank slurry outlet are provided.

[0012] In some embodiments, the stirring device includes a submersible pump, and the submersible pump is disposed in a four-stage pulping box.

[0013] In some embodiments, the system further comprises a detection component for detecting the viscosity, specific gravity and sand content of the mud in the tertiary sedimentation box.

[0014] The utility model adopts a five-stage mud box system. By arranging a sunken conical sedimentation tank in the first-stage sedimentation tank and a three-stage vertical filter screen in the second-stage mud box, on the one hand, the mud after the pile foundation hole is cleaned can be fully and quickly precipitated through the three-stage sedimentation tank and then recycled and effectively utilized; on the other hand, the mud to be recycled is prepared by adding bentonite and admixtures and replacing the mud pump with a submersible pump for rotation and stirring, so that the mud configuration efficiency is higher and more uniform, thereby strictly controlling the performance of the mud entering the hole, improving the stability of the hole wall of the pile foundation in poor geological conditions such as silt and silt sand, controlling the shrinkage, and ensuring the quality of the pile foundation. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A schematic diagram of the system flow of the five-stage mud box configuration for rotary drilling of silt and silt sand geological pile foundations provided by the utility model;

[0016] Figure 2-Figure 7 A schematic diagram of the structure of a primary sedimentation tank and a secondary sedimentation tank provided by the utility model;

[0017] Among them, 1-the slurry outlet at the upper end of the first-level sedimentation box; 2-conical sedimentation tank; 3-the slurry discharge pipe of the first-level sedimentation box; 4-the slurry inlet of the second-level mud box; 5-filter screen; 6-the slurry outlet of the second-level mud box DETAILED DESCRIPTION

[0018] In silt sand layer and silty silt sand layer geology, conventional methods are used to prepare fresh slurry: high viscosity, low solid phase, non-dispersible, low water loss rate bentonite mud, while adding CMC (cellulose), sodium carbonate, PHP and other admixtures, the three major mud indicators are controlled at a specific gravity of 1.08-1.15, a viscosity of 30-35, a pH value of 11-12, and a colloid rate of 100%.

[0019] The mud performance parameters in the rotary drilling stage, the first cleaning stage, and the second cleaning stage are shown in Table 1.

[0020] Table 1 Performance parameters of mud

[0021]

[0022] The pile foundation hole cleaning mud is recycled through the five-level mud pool setting, such as Figure 1 The five-stage mud configuration system includes a primary sedimentation tank, a secondary sedimentation tank, a tertiary sedimentation tank, a quaternary slurrying tank, a primary slurry storage tank, and a five-stage slurry storage tank. The primary sedimentation tank is used to receive the slurry after the pile foundation hole is cleaned; the secondary sedimentation tank is connected and arranged downstream of the primary sedimentation tank, and is used to receive the slurry precipitated by the primary sedimentation tank; the tertiary sedimentation tank is connected and arranged downstream of the secondary sedimentation tank, and is used to receive the slurry precipitated by the secondary sedimentation tank; the quaternary slurrying tank is connected and arranged downstream of the quaternary sedimentation tank, and is used to receive the slurry precipitated by the quaternary sedimentation tank, and the quaternary slurrying tank is equipped with a stirring device for slurry adjustment; the quaternary slurry storage tank is connected and arranged downstream of the quaternary slurrying tank, and is used to store the slurry adjusted by the quaternary slurrying tank and send the slurry into the borehole.

[0023] The on-site mud pool adopts the "container" type. After the pile foundation hole is cleaned, the mud first enters the first-level sedimentation box, and after rapid sedimentation, it enters the second and third-level sedimentation boxes in turn. After the three major performance indicators of mud viscosity, specific gravity and sand content are measured in the third-level sedimentation box, it enters the fourth-level slurry box. According to the results of the mud measurement indicators, bentonite and CMC (cellulose), sodium carbonate, and PHP admixtures are used in the slurry box to mix the slurry. At the same time, a submersible pump (instead of a mud pump) is used to rotate and stir the mud to make the configured mud more uniform to meet the requirements of the new pile foundation construction. In the silt sand layer, silty silt sand layer, and silty clay layer, medium and low speed drilling and slow slag lifting are used to reduce the disturbance of the drilling rig operation to the hole wall.

[0024] In this example, see Figure 2-Figure 7 , the pile foundation after hole cleaning is completed, and the mud after hole cleaning enters the first-level sedimentation box for mud storage and rapid sedimentation. In order to speed up sedimentation, three sunken conical sedimentation tanks are set at the bottom of the box. Then the mud in the first-level sedimentation box is pumped to the second-level sedimentation box for sedimentation. A three-level filter screen is set in the second-level sedimentation box. The filtered mud enters the third-level sedimentation box. The mud index is tested in the third-level sedimentation box, and the mud is pumped to the fourth-level slurry box. Bentonite and admixtures are added according to the mud performance of the third-level sedimentation box to mix the mud and check the three major indicators. After the indicators are qualified, it enters the fifth-level slurry storage box, and a submersible pump is used instead of a mud pump to stir and adjust the mud. After being used for new pile foundation drilling and hole cleaning, it enters the first-level sedimentation tank for circulation.

[0025] The utility model adopts a five-stage mud box system. By arranging a sunken conical sedimentation tank in the first-stage sedimentation tank and a three-stage vertical filter screen in the second-stage sedimentation tank, on the one hand, the mud after the pile foundation hole is cleaned can be fully and quickly precipitated through the three-stage sedimentation tank and then recycled and effectively utilized; on the other hand, the mud to be recycled is prepared by adding bentonite and admixtures and replacing the mud pump with a submersible pump for rotation and stirring, so that the mud configuration efficiency is higher and more uniform, thereby strictly controlling the performance of the mud entering the hole, improving the stability of the hole wall of the pile foundation in poor geological conditions such as silt and silt sand, controlling the shrinkage, and ensuring the quality of the pile foundation.

Claims

1. A five-stage mud preparation system, characterized in that: The system includes: The first-level sedimentation tank is used to receive the mud after the pile foundation is cleaned; A secondary sedimentation tank is connected and arranged downstream of the primary sedimentation tank, and is used to receive the sludge settled in the primary sedimentation tank; A third-stage sedimentation tank, which is connected and arranged downstream of the second-stage sedimentation tank and is used to receive the sludge settled in the second-stage sedimentation tank; A fourth-stage pulping box, which is connected and arranged downstream of the third-stage sedimentation box, and is used to receive the slurry settled in the third-stage sedimentation box. The fourth-stage pulping box is equipped with a stirring device for slurry adjustment; The fifth-stage slurry storage box is connected and arranged downstream of the fourth-stage slurry making box. It is used to store the slurry prepared by the fourth-stage slurry making box and send the slurry into the borehole.

2. The five-stage mud configuration system according to claim 1, characterized in that: A plurality of sunken conical sedimentation tanks are arranged at the bottom of the primary sedimentation tank.

3. The five-stage mud configuration system according to claim 1, characterized in that: The secondary sedimentation box is provided with a three-stage vertical filter screen for filtering mud, and a secondary sedimentation box slurry inlet and a secondary sedimentation box slurry outlet are provided on the filter screen.

4. The five-stage mud configuration system according to claim 1, characterized in that: The stirring device comprises a submersible pump, and the submersible pump is arranged in a four-stage pulping box.

5. The five-stage mud configuration system according to claim 1, characterized in that: The system also includes a detection component for detecting the viscosity, specific gravity and sand content of the mud in the tertiary sedimentation box.

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