A vertical barrier wall square groove casing

Abstract

The utility model relates to the technical field of vertical barrier walls. The vertical barrier wall square groove casing provided by the utility model includes a square inner ring channel steel, a square steel frame, a lifting ring, and a reinforcement channel steel; the square inner ring channel steel is arranged at the top and bottom of the square steel frame and is fixedly connected to the square steel frame; the reinforcement channel steel is arranged on the inner wall of the long side of the square steel frame, and the two ends of the reinforcement channel steel respectively abut against the square inner ring channel steel at the top and bottom of the square steel frame to form an I-shaped structure; the lifting ring is arranged on the top inner ring channel steel. The square groove casing of the utility model is used for dry operation to form a groove, which has little disturbance to the stratum; there is no need to construct a reinforced concrete guide wall, and it can be used in a narrower working space, with low cost, convenience and flexibility, short construction period, safety and stability.

Description

Technical Field

[0001] The utility model relates to the technical fields of solid and hazardous waste landfills such as landfills, soil remediation construction, or municipal and architectural construction, and specifically to a vertical barrier wall grooving casing and a vertical barrier wall grooving construction method. Background Art

[0002] Although the amount of water infiltrating into the garbage pile from rainfall will be greatly reduced after the landfill has been sealed and renovated in a standardized manner, due to the combined effects of the drainage layer and anti-seepage layer of the sealing cover system, some of the early landfills were simple landfills without horizontal anti-seepage systems, or the bottom membrane of the landfill was partially damaged during operation, and leachate will continue to be produced after the decomposition of domestic garbage, resulting in long-term groundwater pollution, posing a great threat to the surrounding and downstream ecological environment and human health. Therefore, the setting of vertical barrier walls is still very necessary.

[0003] A vertical barrier wall is a foundation project in which a narrow and deep trench is excavated on the ground, and an anti-seepage barrier wall made of cement, bentonite and other materials is poured into the deep trench to serve as a water interception, anti-seepage and water retaining structure.

[0004] Vertical barrier walls are often constructed by wet trenching with mud wall protection. Wet trenching requires the construction of reinforced concrete guide walls as support, water storage, and guide structures for the trench section. The preparation period for guide wall construction is long and the cost is high. Wet trenching also requires the disposal of waste mud, making it difficult to ensure safe and civilized construction on site. Wet trenching machinery is usually large-tonnage equipment, and the foundation requirements are high due to the weight of the equipment. At the same time, wet trenching requires the flow of multiple large machines, and the working space requirements are also high.

[0005] At present, the commonly used machines for trenching the foundation of underground vertical barrier walls in rock strata geology are double-wheel milling and rotary drilling with impact drill and grab slotting machine. However, grab slotting machine is suitable for loose alluvial deposits, which are greatly affected by the density of the stratum. It is not suitable for strata containing large stones, boulders, bedrock, etc., and the drilling efficiency is very low. Double-wheel milling is advanced and efficient, suitable for various geological conditions, including bedrock, but the equipment is expensive and the price is high. It requires a sufficiently spacious working space and has high requirements for the bearing capacity of temporary road foundations. Impact drilling is low-cost and suitable for general soft strata. Gravel, pebbles, bedrock, etc. can also be selected, but the drilling efficiency is low, the construction period is long, and wet drilling is required. The drilling efficiency of rotary drilling with impact drill and grab slotting machine is low, the construction period is long, and for strata with less upper miscellaneous fill and silty clay layers and more strongly weathered gravel in the lower part, coupled with a short axis length and a small amount of engineering, the more large-scale machinery is invested, the higher the construction cost.

[0006] Therefore, the construction technology and machinery selection for trenching of underground continuous wall foundations in rock strata geology need to be improved.

[0007] The patent with publication number CN 107964940 A relates to a construction method for underground continuous wall trenching, which includes dividing the excavated land into multiple excavation trench sections according to the design specifications of the underground continuous wall, and marking multiple drilling positions to be drilled above each trench section; preparing mud for drilling; moving the rotary drilling rig to the excavation site, adjusting the rotary drilling rig to the working state, and aligning the drill bit of the rotary drilling rig with the center of one of the drilling positions; starting the rotary drilling rig, and drilling the holes in the drilling positions in a progressive manner; when the first stage of drilling operations for all drilling positions in the trench section is completed by the jump drilling method, a hydraulic grab is used to grab the remaining soil and rocks between the holes to form the first trench body, and then enter the next stage of drilling operations, and so on, until the drilling design depth is reached. This patented technology uses a rotary drill plus a hydraulic grab wet trenching method, and a reinforced concrete guide wall needs to be constructed.

[0008] The patent with publication number CN 114250762 B relates to a method for constructing trenches for underground continuous wall foundations, which includes the following steps: S1, leveling the site; S2, cutting the edges; S3, excavating trenches. The construction method is to form trenches by cutting and excavating. Dry trenching is adopted, and a guide mechanism is installed in the corresponding installation hole, and a rope saw cutter and a rope saw are installed; the rope saw cutter drives the rope saw to cut the edge of the underground continuous wall foundation trench, and the uncut parts are cut into trenches by using a long-arm excavator equipped with a hydraulic circular saw. This patented technology is equipped with a long-arm excavator. Due to the increase in the length of the arm and the bucket arm, its biggest disadvantage is that the operating stability is not high, and the bucket capacity gradually decreases as the arm lengthens, which affects the operating efficiency.

[0009] The patent with publication number CN 111945791A relates to a vertical barrier system for contaminated sites and a construction method. The vertical barrier system for contaminated sites includes an underground continuous wall and high-pressure rotary grouting interlocking piles. The underground continuous wall is vertically arranged around the contaminated site. A plurality of high-pressure rotary grouting interlocking piles are arranged, and each high-pressure rotary grouting interlocking pile is distributed on the inner side of the joints of adjacent underground continuous walls and at the inner corners of the inflection points. The underground continuous wall and the high-pressure rotary grouting interlocking piles together form a barrier system that meets the anti-seepage requirements. The vertical barrier wall is constructed using the underground continuous wall and the high-pressure rotary grouting interlocking piles. Utility Model Content

[0010] In view of the deficiencies in the prior art, the utility model provides a vertical barrier wall square groove casing. When the square groove casing provided by the utility model is used for construction, there is no need to set up a reinforced concrete guide wall. The square groove casing can be flexibly moved, has low cost, and is suitable for dry groove operation.

[0011] The utility model provides a vertical barrier wall forming groove protective tube, which comprises a square inner ring channel steel, a square steel frame, a lifting ring and a reinforcing channel steel; the square inner ring channel steel is arranged at the top and the bottom of the square steel frame and is fixedly connected to the square steel frame; the reinforcing channel steel is arranged on the inner wall of the long side of the square steel frame, and the two ends of the reinforcing channel steel respectively abut against the square inner ring channel steel at the top and the bottom of the square steel frame to form an I-shaped structure; the lifting ring is arranged on the top inner ring channel steel.

[0012] Preferably, the lifting rings are symmetrically arranged on the two long sides of the top inner ring channel steel.

[0013] Specifically, the square inner ring channel steel and the square steel frame are fixedly connected by welding.

[0014] The dry operation referred to in the present invention is relative to the "wet operation", that is, when drilling, water does not need to be injected to form a mud wall, and it is a direct dry operation.

[0015] Beneficial effects:

[0016] The square groove casing provided by the utility model is used for fixing the pile position and serving as a drilling guide; protecting the hole mouth, stabilizing the hole wall, preventing the hole mouth soil layer from collapsing; isolating the surface water of the hole surface and the like. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a process flow chart of a construction method for forming a groove for a vertical barrier wall by using a vertical barrier wall groove casing in a specific embodiment of the utility model;

[0018] Figure 2 It is a schematic diagram of the arrangement of adjacent slot section joints in a specific embodiment of the utility model;

[0019] Figure 3 It is a structural schematic diagram of a groove casing formed by a vertical barrier wall in a specific embodiment of the utility model;

[0020] Figure 4 It is a schematic diagram of the long side orthographic projection structure of the groove casing formed by the vertical barrier wall in the specific embodiment of the utility model;

[0021] Figure 5 It is a schematic diagram of the short side orthographic projection structure of the groove casing formed by the vertical barrier wall in the specific embodiment of the utility model. DETAILED DESCRIPTION

[0022] In order to further understand the content of the utility model, the utility model is described in detail in conjunction with the accompanying drawings and embodiments. It should be understood that the embodiments are only used to explain the utility model but not to limit it.

[0023] Example 1

[0024] like Figure 3-5As shown, in a specific embodiment of the utility model, a vertical barrier wall forms a groove casing, including a square inner ring channel steel 1, a square steel frame 2, a lifting ring 3, and a reinforcement channel steel 4; the square inner ring channel steel 1 is arranged at the top and bottom of the square steel frame 2, and is welded to the square steel frame 2; the reinforcement channel steel 4 is arranged in the longitudinal direction of the inner wall of the long side of the square steel frame 2, and the two ends of the reinforcement channel steel 4 respectively abut against the square inner ring channel steel 1 at the top and bottom of the square steel frame 2 to form an I-shaped structure; the lifting ring 3 is arranged on the top square inner ring channel steel 1. Four lifting rings 3 are symmetrically arranged on the two long sides of the top square inner ring channel steel 1.

[0025] The manufacturing process and parameters of the square groove casing in this embodiment are as follows:

[0026] (1) The square groove casing is made of steel plate and channel steel welded together;

[0027] (2) Use 2cm thick Q235 steel plate;

[0028] (3) The channel steel is a U-shaped channel steel with a width of 10 cm, a height of 4 cm and a thickness of 1 cm;

[0029] (4) The outer edge width of the square groove casing is 1.46m, and the inner effective width is 1.32m;

[0030] (5) The outer edge length of the square groove casing is 4m, and the inner effective length is 3.8m;

[0031] (6) The height of the square trench casing is 2.3m.

[0032] According to the geological survey report and on-site excavation to check the geological conditions, the surface layer of about 2m is backfilled with miscellaneous soil, part of which is silty clay, and the lower soil layer is strongly weathered gravel and medium weathered gravel. The manufacturer formed a trench casing with a height of 2.3m to protect the hole mouth, stabilize the hole wall, and prevent the hole mouth soil layer from collapsing;

[0033] (7) A circle of channel steel is welded at the top and bottom openings of the square groove casing steel plate surface, and two reinforcing channel steels are welded in the depth direction on both sides of the length direction. The horizontal and vertical welding method can support and reinforce the casing, thereby improving the overall stability and lateral support force of the casing;

[0034] (8) Two φ25 plain round steel bars that have not been cold-drawn are welded on both sides of the upper edge of the square groove casing along the length direction as lifting rings. The lifting rings are 13 cm wide and 27 cm long and are welded to the inner ring channel steel at the top of the steel plate frame.

[0035] Example 2

[0036] like Figure 1 As shown, the construction method of vertical barrier wall grooving by using the vertical barrier wall grooving casing provided in Example 1 comprises the following steps:

[0037] S1. Level the site

[0038] In this specific embodiment, the site conditions are as follows: the axis of the vertical barrier wall is located between the south side of the landfill regulating pond and the red line of the wall. The foot of the outer slope of the wall is a drainage ditch, which is close to the farmland. The trough operation space within the red line is limited. If the farmland is temporarily occupied, it is necessary to go through the relevant procedures for temporary occupation with the relevant departments. The subsequent process will involve farmland restoration and acceptance, which is a cumbersome process and also affects the construction period.

[0039] Therefore, the construction method for leveling the site on site is: notify the garden department to remove trees and shrubs, demolish the red line walls, drainage ditches on site, groundwater monitoring wells and other structures that affect the construction, protect the existing cables, optical fibers, pipelines and other pipelines, use GPS, levels and other equipment to measure and mark the axis and elevation of the vertical barrier wall, slope excavation and shaping, level the site, use the excavator tracks to reciprocate and roll, and then use the excavator bucket to compact the soil layer, control the elevation of the working range on both sides of the vertical barrier wall axis to be consistent, avoid equipment tilting and affect the quality of trenching.

[0040] For areas with insufficient working space, in order to provide a stable operating platform for the machinery, the clay with better soil quality on site is used to backfill the slope of the drainage ditch outside the wall. While ensuring that the drainage ditch outside the red line is unobstructed and does not affect the use function, the scope of the machinery working platform is widened while protecting the wall foundation.

[0041] S2. Laying steel plate roadbed box

[0042] After the site is leveled, the excavated land is divided into multiple excavation slots according to the design specifications of the vertical barrier wall, and multiple drilling positions to be drilled are marked above each slot. Along the axis of the vertical barrier wall, a steel plate roadbed box is laid to form a mechanical operation channel.

[0043] Because the vertical barrier wall is located between the south side slope of the regulating pond and the wall, this area is a green area, and the surface layer of about 2m is backfilled with miscellaneous fill soil. If it is excavated and replaced with cement soil, the cost is high, and the bearing capacity of the foundation for heavy engineering machinery vehicles is insufficient, there may be safety hazards such as collapse and instability. Because there is a steel plate roadbed box in the site during the operation of the landfill, it can be used reasonably according to local conditions.

[0044] The roadbed box can be used for paving in soft soil and complex road surfaces, which is convenient for construction vehicles, pile drivers, excavators, rotary drilling rigs and other heavy equipment and vehicles to pass through. The roadbed box is also known as a mobile construction access road, a movable construction road, which is simple and quick to lay, energy-saving and environmentally friendly. It is a quick way to set up a temporary construction access road, and is the best choice for temporary construction access roads and heavy machinery and equipment to enter and exit the site. The roadbed box can make earth-moving vehicles and construction machinery and equipment run quickly and efficiently, thereby improving production efficiency, speeding up construction progress and saving resources. The roadbed box has undergone multiple welding processes, so it is durable and not easy to deform.

[0045] The specifications of the roadbed box used on site in this embodiment are: 5.5m long, 1.5m wide, and 0.14m thick.

[0046] S3, bury the square to form the trench casing

[0047] After the steel plate roadbed box is laid, the trench casing is formed by burying the square, and the two sides around the casing are symmetrically backfilled and compacted;

[0048] The functions of the square groove casing are: (1) fix the pile position and serve as a guide for drilling; (2) protect the hole mouth, stabilize the hole wall, and prevent the soil layer at the hole mouth from collapsing; (3) isolate the water inside and outside the hole.

[0049] S4. Excavation of trenches

[0050] The trench casing formed in step S3 is excavated by a rotary drilling rig;

[0051] The lifting belt passes through the lifting ring of the square trench casing, and the square trench casing is installed on site by using an excavator. The square trench casing is flexible and convenient to transport between trench sections and can be repeatedly used.

[0052] The four lifting rings of the square groove casing are fixed on all sides by pulling them in four directions outwards through steel wire ropes to ensure the stability of the casing and prevent it from sinking and shifting.

[0053] The depth of the tank body and the thickness of the sediment after cleaning shall be inspected according to the design and specification requirements:

[0054] Use a measuring rope to detect the depth of the trough;

[0055] Use a ruler to measure the width of the trough;

[0056] The cleared hole slag rock samples are used to determine whether the requirements of geological exploration and design drawings are met to ensure that the bottom of the vertical anti-seepage wall trench extends into the depth of the impermeable layer.

[0057] Example 3

[0058] In another specific embodiment of the present invention, a vertical barrier wall groove construction method specifically includes the following steps:

[0059] S1. Level the site;

[0060] S2, laying steel plate roadbed box;

[0061] Divide the excavation site into multiple excavation slots according to the design specifications of the vertical barrier wall, and mark multiple drilling positions above each slot. Lay steel plate roadbed boxes along the axis of the vertical barrier wall to form a mechanical operation channel;

[0062] S3, bury the square to form the trench casing

[0063] After the steel plate roadbed box is laid, the buried square forms a trench casing, and the two sides of the casing are symmetrically backfilled and compacted.

[0064] S4. Excavation of trenches

[0065] In this embodiment, a SWDM220 rotary drilling rig is selected; there are many factors that affect the selection of rotary drilling bits, which can be summarized into three aspects: stratum conditions; drilling rig function; hole depth and diameter, ballast thickness, wall protection measures, etc. Since the thickness of the vertical barrier wall in this embodiment is designed to be 1m, in order to ensure the quality and effect of trench casting, a φ1200 roller drill bit is used according to the geological conditions; the hole positions are arranged along the axis of the foundation trench, and the square trench casing is excavated and buried; the rotary drilling rig is moved along the steel plate roadbed box to both sides of the buried square trench casing, and the rotary drilling rig is adjusted to the working state, and the drill bit of the rotary drilling rig is aligned with the center of one of the drilling positions to ensure that the base and the top are stable, and the verticality of the rotary drilling rig is checked and the turntable is calibrated. First, use a φ1200 spiral drill bit with a base to drill and take soil, start the rotary drilling rig, and use progressive drilling operations at the drilling position. The depth of each progressive drilling is 0.5m-1m; when the hole bottom elevation is 0.1-0.2m lower than the design elevation, the vertical anti-seepage bottom extends into the impermeable layer by no less than 2.0m (medium-weathered gravel rock), and the drilling is stopped. During the drilling process, the cut soil blocks are cleaned in time and temporarily piled on the inner side of the vertical barrier wall at the foot of the dam body on the south side of the regulating pool. The excess soil is transported to the pile as a 600mm thick supporting soil layer for sealing and anti-seepage. When the jump drilling method is used to complete the first stage of drilling operations at all drilling positions in the slot section, the φ1200 roller drill bit is replaced to limit the drilling direction, vertically grab the remaining soil and rocks between the holes, and then use the φ1200 spiral roller drill bit with a base to clean the loose soil after the slot body is cut to ensure that the sediment thickness meets the design requirements, form the first slot body, and then enter the next stage of drilling operations, and so on, until the drilling design depth is reached. The use of the square slot casing improves the drilling efficiency and drilling accuracy.

[0066] After the tank is formed, the tank body needs to be inspected according to the design and specification requirements, including the following steps:

[0067] Use a calibrated measuring rope to measure the depth of the trench to ensure the trench depth;

[0068] Use a calibrated tape measure to measure the width of the trough to ensure the thickness of the wall casting;

[0069] The depth of the vertical anti-seepage bottom extending into the impermeable layer is determined by the cleared hole slag. The trench section needs to refer to the geological survey report to meet the design requirements of the vertical anti-seepage wall depth: the vertical anti-seepage bottom extends below the impermeable layer by no less than 2.0m (medium weathered gravel rock), ensuring that a circle of closed vertical barrier walls is formed in the landfill reservoir area, which can cut off the exposure path of pollutants in the contaminated site and the migration of pollution plumes. Although it cannot completely remove pollutants or reduce the concentration of pollutants in the contaminated site, it can prevent contaminated groundwater from flowing into the downstream. Therefore, vertical barrier wall technology can be used alone for risk control of contaminated plots. For different geological conditions, choosing a suitable vertical barrier wall structure can ensure the smooth operation of the landfill.

[0070] In this embodiment, if Figure 2 As shown, the connectors of adjacent slot sections are cast by drilling holes through bite sleeves to achieve overall continuity. There is no need to place joint pipes, joint boxes and other measures, which reduces the investment in auxiliary equipment and materials.

[0071] The utility model has been described through the above embodiments, but it should be understood that the above embodiments are only for the purpose of example and description, and are not intended to limit the utility model to the scope of the described embodiments. It can also be understood by those skilled in the art that the utility model is not limited to the above embodiments, and more variations and modifications can be made according to the teachings of the utility model, and these variations and modifications all fall within the scope of the protection claimed by the utility model. The protection scope of the utility model is defined by the attached claims and their equivalents.

Claims

1. A vertical barrier wall forming groove casing, characterized in that: It includes a square inner ring channel steel, a square steel frame, a lifting ring, and a reinforcement channel steel; the square inner ring channel steel is arranged at the top and bottom of the square steel frame and is fixedly connected to the square steel frame; the reinforcement channel steel is arranged on the inner wall of the long side of the square steel frame, and the two ends of the reinforcement channel steel respectively abut the square inner ring channel steel at the top and bottom of the square steel frame to form an I-shaped structure; the lifting ring is arranged on the top inner ring channel steel.

2. A vertical barrier wall forming groove casing as claimed in claim 1, characterized in that: The lifting rings are symmetrically arranged on the two long sides of the top inner ring channel steel.

3. A vertical barrier wall forming groove casing as claimed in claim 1, characterized in that: The square inner ring channel steel and the square steel frame are fixedly connected by welding.

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