Quick treatment system and method for open caisson mud
Technical Field
The invention relates to the technical field of mud treatment systems, in particular to a rapid open caisson mud treatment system and a rapid open caisson mud treatment method.
Background
The open caisson is a cylindrical structure, is formed by self-sinking to a designed elevation against the frictional resistance of a well wall by means of self gravity, then is closed by concrete and is filled, and is widely applied to municipal works such as large pier foundation pits, sewage pump stations, large equipment foundations, civil air defense shelters, underground lanes and the like. The existing open caisson construction adopts a non-drainage underwater sinking mode, and the extracted muddy water is treated in two modes: 1. by adopting a natural precipitation method, not only a large amount of land is occupied, but also the water in the slurry water cannot be rapidly recycled, so that the construction progress is delayed; 2. the slurry treatment plant is adopted for treatment, the treatment efficiency is low, the equipment investment is high, and the cost is high. The two modes can not realize the rapid recycling of the open caisson mud water, so that the efficiency of open caisson construction is low.
Aiming at the defects, a rapid open caisson mud treatment system and a rapid open caisson mud treatment method are developed. The system filters the muddy water for many times through the overflow dam and the permeable structure arranged in the sedimentation tank, can rapidly finish the muddy water treatment, flows out clear water flow through the drain pipe, immediately supplies water needed by sinking of the sedimentation well, and forms water circulation in a short time. In addition, in the construction process of the system, sand piles generated by open caisson construction are largely utilized, so that waste utilization is realized, and a large amount of cost is saved.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a rapid open caisson mud treatment system and a rapid open caisson mud treatment method.
The invention is realized by the following technical scheme: a rapid open caisson slurry treatment system utilizes a sand-soil pile taken out in an open caisson drainage submerged stage, a sedimentation tank is built beside the open caisson, in the open caisson construction stage, slurry water in the open caisson is conveyed to the sedimentation tank by a slurry inlet pipe for filtration and then discharged by a water discharge pipe for supplying the needed sinking of the open caisson to form water circulation, the sedimentation tank is divided into an inner layer, a middle layer and an outer layer, the first dam body is formed by piling up sand bags at the bottom of the first dam body, an overflow dam is arranged at the top of the first dam body, the slurry inlet pipe is arranged at the top of an inner layer sedimentation tank enclosed by the first dam body, the second dam body is formed by flushing and filling hardening by a multi-layer film bag, a permeable structure is arranged between part of layer film bags, the third dam body is piled up by sand bags, the bottom of the sedimentation tank is further provided with a water discharge pipe, and the slurry inlet pipe and the water discharge pipe are communicated with the open caisson.
Preferably, the heights of the first dam body, the second dam body and the third dam body are the same and are all 2.8m, the overflow dam arranged at the top of the first dam body is a broken stone bag, the thickness of the broken stone bag is set to be 0.2m, the second dam body is formed by filling and hardening four layers of film bags, the four layers of film bags are formed by filling and hardening from bottom to top, a water permeable structure is arranged between the second layer of film bag and the third layer of film bag and between the third layer of film bag and the fourth layer of film bag, and the water permeable structure is formed by paving a pebble layer and a sponge cushion layer.
Preferably, the membrane bags are woven by polypropylene fibers, the width of the membrane bags is reduced layer by layer from bottom to top, the width of the bottom membrane bag is 9-10m, the width of the second membrane bag is 8.5m, the width of the third membrane bag is 6-7m, the width of the fourth membrane bag is 4-4.5m, and the thickness of the four membrane bags is 0.5-0.9m.
Preferably, the pebble layer is laid in a manner that the pebble particle size is 3-5cm, the pebbles are arranged in a plum blossom shape according to the interval of 5cm, the arrangement range is that the top width of the lower layer is 0.5m inwards, the thickness of the sponge cushion layer is 10cm, and the sponge cushion layer is laid above the pebble layer.
The invention also discloses a rapid treatment method of the open caisson mud, which comprises the following steps:
s1, selecting a proper area beside a construction open caisson, stacking sand and soil taken out in the submerged stage of the open caisson row near a preset sedimentation tank, and partially filling sand bags for standby;
S2, carrying out cofferdam lofting according to the size and shape of the sedimentation tank, and discharging preset axes and side lines of the inner sedimentation tank and the outer sedimentation tank;
s3, stacking a first dam body by using sand bags, and paving broken stone bags at the top of the first dam body to form an overflow dam;
S4, constructing a second dam body, paving film bags along the axis of the second dam body, arranging film bag filling openings on the surface, filling the piled sand and soil into the film bags in a sand flushing mode, draining water while filling, filling second to fourth layers of film bags in the same mode after the first layer of film bags are hardened, arranging pebbles on the top surfaces of the second layer and the third layer of film bags, and paving sponge cushions on the pebble layers;
S5, stacking the third dam body by using a sand bag, and reserving a drain pipe.
The invention provides a rapid open caisson mud treatment system and a rapid open caisson mud treatment method. Compared with the prior art, the method has the following beneficial effects:
The system filters the muddy water for many times through the overflow dam and the permeable structure arranged in the sedimentation tank, can rapidly finish the muddy water treatment, flows out clear water flow through the drain pipe, immediately supplies water needed by sinking of the sedimentation well, and forms water circulation in a short time. In addition, in the construction process of the system, sand piles generated by open caisson construction are largely utilized, so that waste utilization is realized, and a large amount of cost is saved.
Drawings
FIG. 1 is a schematic diagram of the structure of an inner, middle and outer three-layer sedimentation tank of the invention;
FIG. 2 is a schematic diagram of the structure of the inner and middle sedimentation tanks according to the present invention;
FIG. 3 is a cross-sectional view of a water permeable structure according to the present invention;
FIG. 4 is a top view of a pebble layer of the invention;
Wherein: 1. a first dam; 2. a second dam; 3. a third dam; 4. a slurry inlet pipe; 5. a drain pipe; 6. a water permeable structure; 101. an overflow dam; 601. a pebble layer; 602. a sponge cushion layer.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Referring to fig. 1-4, the present invention provides a technical solution: a rapid treatment system for open caisson mud uses sand-soil piles taken out in the open caisson drainage submerged stage, a sedimentation tank is built beside the open caisson, in the open caisson construction stage, mud water in the open caisson is conveyed to the sedimentation tank by a slurry inlet pipe 4 to be filtered, and then discharged by a drain pipe 5 to be supplied for open caisson sinking, so that water circulation is formed, and the sedimentation tank is divided into an inner layer, an intermediate layer and an outer layer, and is formed by cofferdams of a first dam 1, a second dam 2 and a third dam 3 respectively.
Specifically, the bottom of the first dam body 1 is formed by stacking sand bags, the top of the first dam body is provided with an overflow dam 101, and the overflow dam 101 is composed of broken stone bags with the thickness of 0.2 m. The slurry inlet pipe 4 is arranged at the top of an inner sedimentation tank surrounded by the first dam body 1 and is used for conveying the open caisson slurry to the inner sedimentation tank. The arrangement of the inner sedimentation tank and the overflow dam 101 ensures that in the slurry sedimentation process, the slurry with lower density at the upper part is filtered to the middle sedimentation tank by the overflow dam, and the water in the middle sedimentation tank is clear, but the use or discharge standard is not met.
The second dam body 2 is formed by filling and hardening four layers of polypropylene fiber woven film bags, the width of the film bags is reduced layer by layer from bottom to top, the width of the bottom film bag is 9m, the thickness is 0.9m, the width of the second layer film bag is 8.5m, the thickness is 0.8m, the width of the third layer film bag is 6.5m, the thickness is 0.6m, the width of the fourth layer film bag is 4.5m, and the thickness is 0.5m. Four layers of membrane bags are arranged between the second layer of membrane bag and the third layer of membrane bag and between the third layer of membrane bag and the fourth layer of membrane bag from bottom to top, a permeable structure 6 is formed by paving pebble layers 601 and sponge cushion layers 602, pebbles are paved in plum blossom shapes at intervals of 5cm, and the sponge cushion layers 602 with the thickness of 10cm are paved above the pebble layers.
Specifically, when the second dam body 2 is constructed, membrane bags are paved along the axis of the second dam body 2, membrane bag filling openings are arranged on the surface, a sand flushing mode is adopted to fill the piled sand soil into the membrane bags, water is discharged while filling, after the first layer of membrane bags are hardened, the second to fourth layers of membrane bags are filled in the same mode, pebbles are arranged on the top surfaces of the second layer of membrane bags and the third layer of membrane bags, and a sponge cushion layer 602 is paved on the pebble layer 601.
Through the permeable structure 6 that sets up, the interior thick liquid water of middle level sedimentation tank can filter to outer sedimentation tank fast, and the effect is showing, is clear rivers in the outer sedimentation tank, reaches the use standard.
The third dam body 3 is formed by stacking sand bags, the bottom is further provided with a drain pipe 5, and clear water flow after two-stage filtration is supplied to a construction open caisson through the drain pipe 5 to form water circulation.
Specifically, the invention also discloses a rapid treatment method of the open caisson mud, which comprises the following steps:
s1, selecting a proper area beside a construction open caisson, stacking sand and soil taken out in the submerged stage of the open caisson row near a preset sedimentation tank, and partially filling sand bags for standby;
S2, carrying out cofferdam lofting according to the size and shape of the sedimentation tank, and discharging preset axes and edges of the inner sedimentation tank, the middle sedimentation tank and the outer sedimentation tank;
S3, stacking the first dam body 1 by using sand bags, and paving broken stone bags at the top of the first dam body 1 to form an overflow dam 101;
S4, constructing a second dam body 2, paving film bags along the axis of the second dam body 2, arranging film bag filling openings on the surface, filling the piled sand and soil into the film bags in a sand flushing mode, draining water while filling, filling second to fourth layers of film bags in the same mode after the first layer of film bags are hardened, arranging pebbles on the top surfaces of the second layer and the third layer, and paving a sponge cushion layer 602 on the pebble layer 601;
s5, stacking the third dam body 3 by using a sand pile, and reserving a drain pipe 5.
Specifically, the invention provides a rapid treatment system and a rapid treatment method for open caisson mud, wherein the sediment rate of an inner sedimentation tank is 20-25%, the sediment rate of an intermediate sedimentation tank is 6-7%, and the sediment rate of an outer sedimentation tank is approximately 0. In order to realize the water circulation of open caisson construction, a traditional natural precipitation method is adopted, so that the water circulation is realized, and at least 3 days are required; mechanical press filtration is adopted for at least 1.5 hours, and the cost of the method is highest; by adopting the rapid open caisson mud treatment system and the rapid open caisson mud treatment method provided by the invention, water circulation is realized for only 8 minutes, and the advantages are obvious.
Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.