Foundation treatment structure of soft soil foundation stock ground

Abstract

The utility model provides a foundation treatment structure of a soft soil foundation stock yard, which comprises foundation backfill soil and a retaining wall, mineral aggregate with multi-stage design working condition height is piled above the foundation backfill soil, a sand cushion layer, a blind ditch and a clay impermeable layer are arranged below the mineral aggregate, the blind ditch is arranged at the position of a wall heel foundation of the retaining wall, and the clay impermeable layer is arranged below the blind ditch. The side end of the clay impermeable layer is in tight contact with the wall heel of the retaining wall, the retaining wall is provided with a horizontal displacement monitoring point and a settlement monitoring point, the deep layer of the retaining wall is provided with a deep inclinometry point, the horizontal displacement monitoring point and the settlement monitoring point are respectively provided with a level gauge, and the deep inclinometry point is provided with an inclinometer. According to the utility model, the deformation condition of the stock ground can be monitored regularly, the ground foundation strength is improved through mineral aggregate preloading drainage consolidation with multi-stage design working condition height, and moisture of mineral aggregate and backfill soil is reduced and discharged through drainage facilities such as the sand cushion layer, the blind ditch and the clay impermeable layer, so that serious water accumulation of the retaining wall is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of coastal soft soil foundation treatment and reinforcement, and particularly relates to a foundation treatment structure for a soft soil foundation material yard. Background Art

[0002] Most of the main iron and steel metallurgy enterprises in China are located on the soft soil foundation in the coastal area. The soft soil foundation has a high water content and high compressibility, resulting in low foundation bearing capacity and large uneven settlement. Generally, it should be subjected to foundation treatment before being used as an industrial workshop.

[0003] Commonly used treatment methods for soft soil foundations include drainage consolidation methods (such as surcharge preloading, vacuum preloading, etc.), gravel piles, cement mixing piles, cement fly ash gravel piles, pile-net composite foundation methods, etc. The deficiencies of the existing foundation treatment structures are that the strength after foundation treatment is still low, the slurry is easy to block the plastic drainage board, the drainage effect is weak, and in addition, there are also disadvantages such as relatively high project cost and difficult control of post-construction settlement. Content of the Utility Model

[0004] Aiming at the deficiencies of the above-mentioned existing technologies, the utility model provides a foundation treatment structure for a soft soil foundation material yard. By forming a drainage system for the foundation soil with blind ditches and sand cushions, and using graded stockpiling as a pressure system, the foundation bearing capacity is gradually improved through the drainage consolidation of the foundation soil, and finally it meets the load requirements, having extremely high suitability and economy.

[0005] The technical solution provided by the utility model: A foundation treatment structure for a soft soil foundation material yard, including foundation backfill soil and a retaining wall. There are multiple levels of ore materials piled above the foundation backfill soil at the designed working height. Below the ore materials, there are a sand cushion, blind ditches and a clay impermeable layer. The blind ditches are arranged at the retaining wall heel foundation. The side end of the clay impermeable layer is in close contact with the retaining wall heel. Horizontal displacement monitoring points and settlement monitoring points are arranged on the retaining wall, and deep inclinometer points are arranged deep in the retaining wall. Level meters are respectively arranged at the horizontal displacement monitoring points and settlement monitoring points, and inclinometers are arranged at the deep inclinometer points.

[0006] Furthermore, the foundation treatment structure further includes a reclaimer track arranged in the material yard. A reclaimer for stockpiling and reclaiming materials is arranged on the reclaimer track. Horizontal displacement monitoring points, settlement monitoring points and deep inclinometer points are all arranged on the reclaimer track and the reclaimer.

[0007] Furthermore, the lower part of the ore materials is fully covered with interlocking floor tiles with strong water permeability to isolate the contact between the ore materials and the foundation soil.

[0008] Furthermore, the sand cushion at the top of the blind ditch is flush with the bottom of the interlocking floor tiles.

[0009] Further, the backfill material in the blind ditch is selected as graded gravel with good water permeability, mud content less than 5%, and particle size of 30 - 60 mm. A layer of geotextile with a lap length of not less than 0.5 m is wrapped outside the backfilled graded gravel.

[0010] Further, the clay impervious layer is arranged below the geotextile and has a thickness of not less than 500 mm.

[0011] Further, the depth of the blind ditch is not less than 0.5 m, the bottom slope of the water flow collection direction is not less than 1‰, and it slopes from the middle to both ends. The water in the blind ditch is discharged into the site drainage system.

[0012] Further, the mineral materials are provided with four levels of stacking heights, and the first - level stacking height of the mineral materials is the same as the height of the retaining wall.

[0013] The beneficial effects of the present utility model are as follows:

[0014] (1) The present utility model treats the soft soil foundation through the large - area stacking of overlying mineral materials. The multi - level designed working condition heights of the mineral material stacking are used for preloading and drainage consolidation to improve the foundation strength of the site. Moreover, the stacking process is continuously monitored, and the next - level stacking material is determined according to the growth of the soil strength. The whole process is under control;

[0015] (2) According to the results of vertical settlement and horizontal displacement monitoring, the positions and elevations of the reclaimer and the reclaimer track can be adjusted to ensure the normal operation of stacking and reclaiming;

[0016] (3) The deformation of the stockyard can be monitored regularly. Through drainage facilities such as sand cushions, blind ditches, and clay impervious layers, the moisture of the mineral materials and the backfill soil can be reduced and drained to avoid serious water accumulation in the retaining wall. Description of the Drawings

[0017] Figure 1 is the structural schematic diagram of the present utility model;

[0018] Figure 2 is the structural schematic diagram of the drainage part of the present utility model;

[0019] In the figure: 1 - column; 2 - retaining wall; 201 - retaining wall facing the mineral materials; 202 - retaining wall heel; 3 - mineral materials; 4 - interlocking floor tiles; 5 - sand cushion; 6 - blind ditch; 601 - gravel; 602 - geotextile; 7 - clay impervious layer; 8 - foundation backfill soil; 9 - reclaimer; 10 - reclaimer track. Detailed Embodiments

[0020] The following further describes the present utility model in conjunction with specific embodiments. Among them, the attached drawings are only for illustrative purposes, showing only schematic diagrams rather than physical diagrams, and should not be construed as a limitation to the present utility model. In order to better illustrate the specific embodiments of the present utility model, some components in the attached drawings will be omitted, enlarged or reduced, which do not represent the dimensions of the actual product. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the attached drawings may be omitted. Based on the specific embodiments of the present utility model, all other specific embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present utility model.

[0021] In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "front", "rear", "upper", "lower", etc. is based on the orientation or positional relationship shown in the attached drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present utility model. In addition, the terms "first", "second", etc. are only used for distinguishing descriptions and cannot be construed as indicating or implying relative importance. In the description of the present utility model, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "provided with", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0022] As Figure 1-2 shown, a foundation treatment structure for a soft soil foundation material yard includes foundation backfill soil 8 and a retaining wall 2. Above the foundation backfill soil 8, mineral materials 3 with multiple design working condition heights are stacked. Below the mineral materials 3, a sand cushion layer 5, a blind drain 6, and a clay anti-seepage layer 7 are provided. The blind drain 6 is arranged at the foundation of the retaining wall heel 202 to drain surface water, avoid the foundation soil being soaked by water, and prevent foundation softening and uneven settlement. The side end of the clay anti-seepage layer 7 is in close contact with the retaining wall heel 202. Horizontal displacement monitoring points and settlement monitoring points are arranged on the retaining wall 2, and deep inclinometer points are arranged deep in the retaining wall 2. Level gauges are respectively arranged at the horizontal displacement monitoring points and settlement monitoring points, and inclinometers are arranged at the deep inclinometer points.

[0023] The foundation treatment structure further includes a reclaimer track 10 arranged in the stockyard. A reclaimer 9 for piling and reclaiming materials is provided on the reclaimer track 10. Horizontal displacement monitoring points, settlement monitoring points, and deep inclinometer points are all provided on the reclaimer track 10 and the reclaimer 9. During the surcharge process, the foundation soil will deform, affecting the surrounding reclaimer and track, resulting in deflection and settlement. By setting monitoring points and reasonably adjusting the piling height, the overall situation can be kept in a stable and controlled state.

[0024] Interlocking floor tiles 4 with strong water permeability are fully paved under the mineral materials 3, with a thickness of 100 mm. The joints between the floor tiles are filled with sea sand to isolate the contact between the mineral materials 3 and the foundation backfill soil 8, accelerate the drainage of the mineral materials, and reduce the moisture content of the mineral materials.

[0025] The sand cushion layer 5 at the top of the blind ditch 6 is flush with the bottom of the interlocking floor tiles 4. The backfill material in the blind ditch 6 is selected as graded gravel 601 with good water permeability, a mud content of less than 5%, and a particle size of 30 - 60 mm. A woven geotextile 602 with an overlap length of not less than 0.5 m is wrapped outside the backfilled graded gravel 601.

[0026] The bottom width of the blind ditch 6 is 0.8 - 1.0 m, the slope is 1:0.5, the depth is 0.8 - 1.0 m, and the bottom slope of the water flow collection direction is not less than 1‰, sloping from the middle to both ends. The water in the blind ditch 6 is discharged into the site drainage system.

[0027] A clay impermeable layer 7 with a thickness of not less than 500 mm is provided under the geotextile 602. The side end of the clay impermeable layer 7 should be in close contact with the wall heel 202 of the retaining wall to prevent the geotextile in the blind ditch from seeping water and reduce the drainage effect of the ground surface water accumulation.

[0028] Before piling the materials in the present utility model, the embedding work of the monitoring and test area test instruments and the measurement and detection work before the test must be completed, the initial value data such as horizontal displacement, settlement displacement, and deep displacement are obtained, and the first round of soil investigation is carried out to obtain relevant geotechnical mechanical parameters.

[0029] The mineral materials 3 are provided with four levels of surcharge heights. The surcharge height H1 near the ore-facing surface of the retaining wall in the first working condition should be consistent with the height of the retaining wall. After the degree of consolidation of the foundation reaches 80% under the action of the effective piling height H1 in the first working condition, the piling is started to the piling height H2 in the second working condition. Before starting the piling of the next working condition, a soil investigation should be carried out, and the stability calculation and analysis of the stockyard should be carried out according to the relevant physical and mechanical property index parameters, and it should be evaluated whether the piling of the next working condition can be carried out. Only when the soil strength is increased to the required value is it allowed to transfer to the next piling height. This cycle is repeated until the final working condition design surcharge height H4 is reached.

[0030] The ore materials are stockpiled in multiple working conditions according to the process design. The ore stockpiling height in each working condition should maintain a sufficient effective ore storage time to ensure that the degree of consolidation of the foundation soil and the dissipation degree of excess pore water reach the standards required for the stability check of the lower-level load. During the stockpiling process, the monitoring frequency should be strengthened, and problems should be unloaded and decompressed in a timely manner. The ore materials should be evenly preloaded by stacking, and the upper load should be evenly distributed to avoid uneven settlement caused by concentrated loads. The upper stepped distributed stacking load should not be changed to triangular concentrated stacking load.

[0031] The monitoring points should be set at easily observable locations to prevent the ore materials from covering and making it impossible to monitor. The bottom of the deep horizontal displacement points should be embedded in the strongly weathered rock by no less than 1 m. During the monitoring process, if large-scale settlement, severe uneven settlement, or severe cracks are found, or if sudden increases or decreases in the ground load near the foundation, a large amount of water accumulation around the foundation, or long-term continuous rainfall occur, the monitoring frequency should be increased, and a safety emergency plan should be implemented.

[0032] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A foundation treatment structure for a soft soil foundation material field, characterized in that: The invention comprises a foundation backfill (8) and a retaining wall (2). The foundation backfill (8) is piled with mineral materials (3) of multiple design working condition heights. A sand cushion layer (5), a blind ditch (6) and a clay anti-seepage layer (7) are arranged below the mineral materials (3). The blind ditch (6) is arranged at the base of the retaining wall heel (202). The side end of the clay anti-seepage layer (7) is in close contact with the retaining wall heel (202). The retaining wall (2) is provided with horizontal displacement monitoring points and settlement monitoring points. The deep layer of the retaining wall (2) is provided with deep inclinometer points. Levels are arranged at the horizontal displacement monitoring points and the settlement monitoring points respectively. An inclinometer is arranged at the deep inclinometer point.

2. The foundation treatment structure of a soft soil foundation material field according to claim 1, characterized in that: The foundation treatment structure also includes a reclaimer track (10) arranged in the material yard, on which a reclaimer (9) for stacking and reclaiming materials is arranged, and both the reclaimer track (10) and the reclaimer (9) are provided with horizontal displacement monitoring points, settlement monitoring points and deep inclination measurement points.

3. The foundation treatment structure of a soft soil foundation material field according to claim 1, characterized in that: The lower part of the mineral material (3) is fully paved with highly permeable interlocking floor tiles (4) to isolate the mineral material (3) from contact with the foundation backfill soil (8).

4. The foundation treatment structure of a soft soil foundation material field according to claim 3, characterized in that: The sand cushion layer (5) on the top of the blind ditch (6) is flush with the bottom of the interlocking floor tile (4).

5. The foundation treatment structure of a soft soil foundation material field according to claim 1, characterized in that: The backfill material in the blind ditch (6) is graded crushed stone (601) with good water permeability, mud content less than 5% and particle size of 30-60 mm. The backfill graded crushed stone (601) is wrapped with a layer of geotextile (602) with an overlap length of not less than 0.5 m.

6. The foundation treatment structure of a soft soil foundation material field according to claim 5, characterized in that: The clay anti-seepage layer (7) is arranged at the bottom of the geotextile (602) and has a thickness of not less than 500 mm.

7. The foundation treatment structure of a soft soil foundation material field according to claim 1, characterized in that: The blind ditch (6) has a depth of not less than 0.5 m, a bottom slope in the direction of water flow convergence of not less than 1‰, and is inclined from the middle to two sections. The water in the blind ditch (6) is discharged into the drainage system in the site.

8. The foundation treatment structure of a soft soil foundation material field according to claim 1, characterized in that: The mineral material (3) is provided with four levels of stacking heights, and the first level of stacking height of the mineral material (3) is consistent with the height of the retaining wall (2).

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