CN-116985254-B - Construction method for recycling foundation pit soil

CN116985254BCN 116985254 BCN116985254 BCN 116985254BCN-116985254-B

Abstract

The invention relates to the technical field of foundation pit soil and discloses a construction method for recycling the foundation pit soil, which comprises the following construction steps of 1) separating fine materials from coarse materials in the foundation pit soil, mixing the fine materials with water to form slurry, discharging the coarse materials along a vibrating screen, 2) crushing the coarse materials to form crushed materials, feeding the crushed materials into a multi-layer screen to form powder, 3) pressing the slurry to form slurry, 4) mixing the slurry with the powder to form aggregate, 5) mixing and stirring the aggregate, cement and water to form a mixture, 6) conveying the mixture to a plurality of die cavities to perform vibration pressing to form a brick blank, 7) curing the brick blank for a set time to form a finished brick, forming the foundation pit soil in construction, mixing and stirring the aggregate, the cement and the water to form a mixture, and forming the mixture into a brick blank in a bench vibrating press, so that the utilization rate of the soil and the effect of protecting the environment are improved, and the effective treatment of the foundation pit soil is better realized.

Inventors

LEI BIN
FENG DONGDONG
WANG ZHIQUAN
YANG JING
LIU ZHIMING
Liu Diebo
SUN XIAOHUI
TONG XIN
LI XINLIN
Lin Muyou
LIN QIANGYOU
Sha Zhenhui
YANG JUNQING
LI KAI

Assignees

深圳市工勘岩土集团有限公司
深圳大学

Dates

Publication Date: 20260508
Application Date: 20230724

Claims (8)

1. The construction method for recycling the foundation pit soil is characterized by comprising the following construction steps of: 1) Flushing and filtering foundation pit soil through a soil body vibrating screen, mixing fine materials in the foundation pit soil with a water body to form slurry, and discharging the slurry into a slurry pond for standby, wherein coarse materials in the foundation pit soil are discharged along the vibrating screen; 2) Crushing the coarse materials in a crusher to form crushed materials, and carrying out multilayer screening on the crushed materials to form powder; 3) Squeezing the slurry to obtain water through a squeezer to form a pug; 4) Mixing and stirring the pug and the powder to form aggregate; 5) Mixing and stirring the aggregate, cement and water to form a mixture; 6) The mixture is conveyed into a die of a bench die vibration press, wherein the die is provided with a plurality of die cavities; 7) Separating the green bricks from the mould, and curing for a set time to form finished bricks; The die vibration press is provided with a vibration table, a supporting plate is arranged on the vibration table, the die is arranged on the supporting plate, a plurality of die cavities are arranged in the die, and the die cavities are arranged in an array manner; In the construction step 6), in the process of placing the mixture into a plurality of mold cavities, the vibrating table drives the mold to vibrate up and down and horizontally, and the mixture placed in the mold cavities is subjected to preliminary vibration; in the construction step 6), after the die cavity is filled with the mixture, the pressure head moves towards the die until a plurality of lower pressure plates are propped against the mixture in the die cavity from top to bottom, the lower pressure plates apply downward static load pressure to the mixture, the vibration table drives the die to vibrate up and down, and secondary vibration is carried out on the mixture in the die cavity, so that the mixture in the die cavity forms green bricks; The vibrating table is provided with a placing position for placing the supporting plate, a lower air cavity is arranged in the placing position, and the lower air cavity is connected with the air charging and sucking equipment; a plurality of upper air cavities are arranged in the supporting plate, a plurality of vent holes are arranged at the bottom of the supporting plate, and the vent holes are correspondingly communicated with the upper air cavities respectively; the support plate is provided with a plurality of brick supporting positions corresponding to the die cavities, and the plurality of brick supporting positions are respectively aligned with the plurality of upper air cavities up and down; In the construction step 6), the supporting plate is placed on a placement position, the bottom of the supporting plate is abutted against the sealant ring, the periphery of the lower air cavity is sealed, and the lower air cavity is communicated with a plurality of upper air cavities through a plurality of vent holes; in the construction step 6), when the mixture is placed in the die cavity, the upper air cavity is kept in a normal pressure state, and when the lower pressing plate is inserted into the die cavity and is pressed downwards against the mixture in the die cavity, and the vibrating table drives the die to vibrate up and down, high-pressure gas is injected into the lower air cavity by the air charging and sucking device, and the high-pressure gas presses the mixture from bottom to top through the upper air hole; in the construction step 7), when the lower pressing plate is downward to separate the green bricks from the die cavity, the air charging and sucking device charges air into the lower air cavity so as to enable the upper air cavity to form a negative pressure state.
2. The construction method for recycling the foundation pit soil according to claim 1, wherein in the construction step 1), a washing tank is arranged at a construction site, the soil body vibrating screen is arranged above the washing tank, and a top water spraying pipe is arranged above the soil body vibrating screen; When foundation pit soil is placed on the soil body vibrating screen for vibration transmission, the top water spraying pipe sprays water downwards, the water is mixed with the foundation pit soil, fine materials in the foundation pit soil and the water penetrate through the soil body vibrating screen and are placed in the filter tank to form slurry, and coarse materials in the foundation pit soil are discharged along the soil body vibrating screen.
3. The construction method for recycling the foundation pit soil according to claim 2, wherein the soil body vibrating screen is provided with bottom water spraying pipes which are arranged in a net shape, the bottom water spraying pipes are distributed along the plane direction of the soil body vibrating screen, and in the construction step 1), when the foundation pit soil is placed on the soil body vibrating screen for vibration transmission, the bottom water spraying pipes spray water at intervals from bottom to top, the foundation pit soil is flushed from bottom to top, and the top water spraying pipes spray water from top to bottom, and the foundation pit soil is flushed from top to bottom.
4. A foundation pit soil recycling construction method according to any one of claims 1 to 3, wherein in the construction step 2), the crusher is a cone crusher, and the coarse material is crushed by the cone crusher; the cone crusher is internally provided with a crushing cavity, the periphery of the middle part of the crushing cavity is provided with a fixed crushing wall, the crushing cavity is internally provided with a rotating cone head which eccentrically rotates, and the periphery of the rotating cone head is provided with a rotating crushing wall; The fixed crushing wall and the rotary crushing wall are respectively and obliquely arranged inwards along the bottom-up direction of the crushing cavity, a crushing interval is formed between the fixed crushing wall and the rotary crushing wall, and the crushing interval is circumferentially arranged along the periphery of the rotary cone; in the construction step 2), the coarse materials are crushed by the extrusion of the fixed crushing wall and the rotary crushing wall in the process of passing through the crushing interval from top to bottom, so as to form the crushed materials.
5. A foundation pit soil recycling construction method according to any one of claims 1 to 3, wherein in the construction step 2), the crushed material is screened by a screening structure to form powder; the screening structure comprises a plurality of material body vibrating screens which are sequentially arranged up and down, wherein the plurality of material body vibrating screens are obliquely arranged, vibrating screen holes are formed in the material body vibrating screens, and in the construction step 2), in the process that the crushed materials are conveyed along the material body vibrating screens from top to bottom, the crushed materials with the diameters smaller than those of the vibrating screen holes fall down through the vibrating screen holes to form powder.
6. The construction method for recycling the foundation pit soil according to claim 5, wherein a return material conveying belt is arranged between the material body vibrating screen and the cone crusher, In the construction step 2), the crushed materials which do not fall through the vibrating screen holes move downwards along with the material body vibrating screen and fall on a return conveying belt, and the return conveying belt conveys the crushed materials back to the cone crusher.
7. A method of constructing a pit soil recycling according to any one of claims 1 to 3, wherein in the constructing step 3), after the slurry is fed into a slurry press, a flocculant is added to the slurry, and after a set time of standing, the slurry is fed into a dewatering zone where the slurry is placed in two mesh belts moving in the same direction and moves in synchronization with the mesh belts; And in the synchronous transmission process of the slurry along with the mesh belt, rolling the mesh belt by using a rolling roller, and rolling the slurry to form the pug.
8. A foundation pit soil recycling construction method according to any one of claims 1 to 3, wherein in the construction step 4), the slurry and the powder are placed in a stirrer to be stirred, so as to form the aggregate; In the construction step 5), the metered aggregate and cement are placed in a stirrer, after the aggregate and cement are mixed and stirred in the stirrer for a set time, the metered water body is injected into the stirrer, and the water body, the mixed and stirred aggregate and cement are mixed and stirred for the set time, so that the mixture is formed.

Description

Construction method for recycling foundation pit soil Technical Field The invention relates to the technical field of foundation pit soil, in particular to a construction method for recycling the foundation pit soil. Background Along with the continuous and rapid increase of the economy in China, the construction industry suddenly and rapidly advances, and the discharge amount of various construction wastes is increased year by year, wherein the amount of foundation pit soil excavated by the deep foundation pit is increased. The foundation pit soil is also provided with coarse materials and fine materials, wherein the coarse materials are particles with the particle diameter of more than 4mm, the mass ratio of round gravel to boulder is more than 50%, and the fine materials are powdery clay mainly in a plastic cake shape. In the prior art, with the popularization of comprehensive utilization of construction waste, foundation pit soil is generally washed and filtered, coarse materials and fine materials are separated, the fine materials are formed into slurry, the slurry is pressed to form a mud cake, and then the coarse materials and the slurry are transported outwards to be buried, so that the large transportation capacity exists, the effect of recycling the foundation pit soil is difficult to realize, and the purposes of green construction and resource treatment and recycling are not met. Disclosure of Invention The invention aims to provide a construction method for recycling foundation pit soil, and aims to solve the problem that in the prior art, foundation pit soil is difficult to effectively treat. The invention discloses a construction method for recycling foundation pit soil, which comprises the following construction steps: 1) Flushing and filtering foundation pit soil through a soil body vibrating screen, mixing fine materials in the foundation pit soil with a water body to form slurry, and discharging the slurry into a slurry pond for standby, wherein coarse materials in the foundation pit soil are discharged along the vibrating screen; 2) Crushing the coarse materials in a crusher to form crushed materials, and carrying out multilayer screening on the crushed materials to form powder; 3) Squeezing the slurry to obtain water through a squeezer to form a pug; 4) Mixing and stirring the pug and the powder to form aggregate; 5) Mixing and stirring the aggregate, cement and water to form a mixture; 6) The mixture is conveyed into a die of a bench die vibration press, wherein the die is provided with a plurality of die cavities; 7) And removing the green bricks from the mould, and curing for a set time to form the finished bricks. Further, in the construction step 1), a washing tank is arranged at a construction site, the soil body vibrating screen is arranged above the washing tank, and a top water spraying pipe is arranged above the soil body vibrating screen; When foundation pit soil is placed on the soil body vibrating screen for vibration transmission, the top water spraying pipe sprays water downwards, the water is mixed with the foundation pit soil, fine materials in the foundation pit soil and the water penetrate through the soil body vibrating screen and are placed in the filter tank to form slurry, and coarse materials in the foundation pit soil are discharged along the soil body vibrating screen. In the construction step 1), when foundation pit soil is placed on the soil vibrating screen for vibration transmission, the bottom water spray pipes spray water at intervals from bottom to top, wash foundation pit soil from bottom to top, and the top water spray pipes spray water from top to bottom and wash foundation pit soil from top to bottom. Further, in the construction step 2), the crusher is a cone crusher, and the coarse material is placed in the cone crusher for crushing; the cone crusher is internally provided with a crushing cavity, the periphery of the middle part of the crushing cavity is provided with a fixed crushing wall, the crushing cavity is internally provided with a rotating cone head which eccentrically rotates, and the periphery of the rotating cone head is provided with a rotating crushing wall; The fixed crushing wall and the rotary crushing wall are respectively and obliquely arranged inwards along the bottom-up direction of the crushing cavity, a crushing interval is formed between the fixed crushing wall and the movable crushing wall, and the crushing interval is circumferentially arranged along the periphery of the rotary cone; In the construction step 2), the coarse materials are extruded and crushed by the fixed crushing wall and the movable crushing wall in the process of passing through the crushing interval from top to bottom, so as to form the crushed materials. Further, in the construction step 2), the crushed materials are screened through a screening structure to form powder; the screening structure comprises a plurality of material body vibrating screens whi