阅读说明：本技术 一种环保复合型防绕渗柔性竖向隔离系统及安装方法 (Environment-friendly composite type anti-seepage flexible vertical isolation system and installation method ) 是由 伍浩良 毕钰璋 于 2020-05-13 设计创作，主要内容包括：本发明公开了一种环保复合型防绕渗柔性竖向隔离系统及安装方法,其隔离系统包括用于阻滞地下水及土壤中污染物的防绕渗构件,所述防绕渗构件包括预制的纤维增强水泥基材料或碳化氧化镁基材料,所述防绕渗构件表面形成预留两口的闭合螺栓,两个防绕渗构件相互夹持有同一个柔性防渗墙体,所述柔性防渗墙体由矩形高密度聚乙烯土工膜构成；该系统可解决土工膜与槽底不透水层接触不良引起的泄露问题,能满足在极端的地震或者大型地质活动下保持防渗性,其采用环保型材料氧化镁,利用碳化方法加速构件形成,可以达到综合利用环保材料、吸收二氧化碳、高效产出防绕渗材料具有高延性的积极效果。(The invention discloses an environment-friendly composite type anti-seepage flexible vertical isolation system and an installation method, wherein the isolation system comprises an anti-seepage component for blocking pollutants in underground water and soil, the anti-seepage component comprises a prefabricated fiber reinforced cement-based material or a magnesium carbide oxide-based material, two closed bolts with two reserved openings are formed on the surface of the anti-seepage component, the two anti-seepage components mutually clamp a same flexible anti-seepage wall body, and the flexible anti-seepage wall body is formed by a rectangular high-density polyethylene geomembrane; the system can solve the leakage problem caused by poor contact between the geomembrane and the impervious bed at the bottom of the tank, can meet the requirement of maintaining the seepage-proofing property under extreme earthquakes or large-scale geological activities, adopts environment-friendly material magnesium oxide, is formed by accelerating components by a carbonization method, and can achieve the positive effects of comprehensively utilizing the environment-friendly material, absorbing carbon dioxide, efficiently producing the anti-seepage material and having high ductility.)

1. The utility model provides a compound anti-seepage flexible vertical isolation system that prevents to detour including the anti-seepage component (1) that is arranged in retarding groundwater and soil pollutant, wherein characterized in that, prevent to detour and ooze component (1) including prefabricated fiber reinforced cement base material or magnesium oxide carbide base material, prevent to form around oozing component (1) surface and reserve two mouthful of close bolt (3), two prevent that to detour and ooze component (1) centre gripping each other and have same flexible impervious wall body (2), flexible impervious wall body (2) comprise rectangle high density polyethylene geomembrane.

2. An environmentally friendly composite type anti-seepage flexible vertical isolation system according to claim 1, wherein the prefabricated anti-seepage component (1) has a material mixing ratio of type I, wherein the material mixing ratio of type I is as follows: the mass ratio of the quick self-hardening cement to the magnesia to the natural sand to the fly ash to the water to the polycarboxylic water reducer is as follows: 0.94-1: 0-0.06: 0.6-0.8: 1.2-2.2: 0.56: 0.07-0.12, wherein the I-type prefabricated anti-seepage component (1) is doped with fibers, and the fibers account for 0.8-1.2% of the total volume;

or the material mixing ratio of the prefabricated seepage-proofing component (1) can be type II: the mass ratio of the magnesium oxide, the fly ash, the water, the sodium hexametaphosphate and the polycarboxylic water reducer is as follows: 5-7: 3-5: 0.52: 0.06-0.12: 0.007-0.008, wherein the type II prefabricated penetration-proof component (1) is doped with fibers, and the fibers account for 0.8-1.2% of the total volume.

3. The environment-friendly composite type anti-seepage flexible vertical isolation system according to claim 1, wherein the flexible anti-seepage wall body (2) has the following size proportions of length, width and height: 10: 0.5-1.5: 0.4-1.2, wherein the two close bolts (3) are stainless steel double-headed stud bolts, and the bolt size is M10-M30 standard bolts.

4. The environment-friendly composite type anti-seepage flexible vertical isolation system according to claim 1, wherein the anti-seepage member (1) is composed of two prefabricated cuboid members, the rectangular high-density polyethylene geomembrane is embedded between the two prefabricated members, and the anti-seepage member (1) is embedded in an underground impermeable layer.

5. The environment-friendly composite type anti-seepage flexible vertical isolation system according to claim 1, wherein the cement is fast-hardening aluminate cement, the magnesium oxide is light magnesium oxide, the magnesium oxide is industrial grade light magnesium oxide with the mass content of 70-88%, the maximum particle size of the natural sand is river sand or basalt sand or gabbro sand with the particle size less than 0.5mm, the fly ash is domestic grade 1-2 fly ash, the water is industrial tap water, the water reducing agent is a polycarboxylic water reducing agent, the fibers can be polyvinyl alcohol and polypropylene fibers in synthetic fibers, and can be sugarcane fibers or acetate fibers in artificial fibers and cellulose fibers in natural fibers.

6. The environment-friendly composite type anti-seepage flexible vertical isolation system according to claim 1, wherein in the I-shaped prefabricated anti-seepage component, the prefabrication method comprises the steps of uniformly stirring the quick self-hardening cement, the magnesium oxide, the natural sand, the fly ash, the water and the polycarboxylic water reducer, adding the specific fiber of claim 5, quickly stirring, pouring into the prefabricated component mold of claim 3, curing at 20-25 ℃ for 6 hours, demolding, molding, and then curing for 2 days.

7. The environment-friendly composite type anti-seepage flexible vertical isolation system according to claim 1, wherein in the type II prefabricated anti-seepage component, the prefabrication method comprises the steps of uniformly stirring magnesium oxide, fly ash, water, sodium hexametaphosphate and a polycarboxylic water reducing agent, adding the specific fiber of claim 5, quickly stirring, pouring into the prefabricated component mold of claim 3, curing at 20-25 ℃ for 6h, demolding, molding, and then carbonizing and curing in a carbonization box for 1-12h, wherein the concentration of carbon dioxide in the carbonization box is 60-98%, and the curing atmospheric pressure value is 1.2-5.8 MPa.

8. The environment-friendly composite type anti-seepage flexible vertical isolation system according to claim 6 or 7, wherein the sodium hexametaphosphate and the polycarboxylate type water reducing agent are respectively stirred with water to form a mixed solution 1 and a mixed solution 2, the stirring temperature of the mixed solution 1 is 65-110 degrees, and the stirring temperature of the mixed solution 2 is 10-20 degrees.

9. The installation method of the environment-friendly composite anti-seepage flexible vertical isolation system is characterized by comprising the following steps of:

s1: prefabricating a seepage-proof member: prefabricating anti-seepage members with corresponding quantity and length according to the requirements of an actual polluted site, and cutting a corresponding wide high-density polyethylene geomembrane;

s2: manufacturing a seepage prevention unit: inserting a single vertical high-density polyethylene geomembrane into the two prefabricated anti-seepage components, and fixing the prefabricated anti-seepage components and the vertical high-density polyethylene geomembrane by using stud threaded bolts to form a composite anti-seepage flexible vertical isolation unit;

s3: grooving: vertically slotting along the peripheral position of a constructed polluted site, excavating the slot bottom into an underground impervious layer, and adopting domestic commercial bentonite slurry with the mass ratio of 2% to protect the wall in the vertical slotting process;

s4: forming an anti-seepage system: inserting the impervious wall unit obtained in the step S2 into a vertical slot in the retaining wall slurry of the vertical slot, wherein the anti-seepage support part is placed at the bottom of the vertical slot;

s5: repeating the step S4 to enable each anti-seepage unit to be in close contact, wherein the high-density polyethylene geomembranes of the anti-seepage units are connected in a hot-melt butt joint mode;

s6: grouting: corresponding bentonite slurry is injected into the groove by adopting a pumping mode to cover the joint of the anti-winding member;

s7: backfilling: the trench is backfilled with sand and clay or a mixture thereof to remove the retaining wall mud.

Technical Field

The invention relates to the technical field of ecological environment restoration, in particular to an environment-friendly composite type anti-seepage flexible vertical isolation system and an installation method.

Background

The environmental damage is more and more serious while the industrialization of China is rapidly developed. In particular, some chemical and mining enterprises do not take anti-seepage measures on the existing solid waste storage yard, mine dump leaching yard, tailing pond and the like, so that toxic and harmful substances harm the ecological environment through various ways, pollute soil and underground water and seriously affect the normal life and body health of people.

With the progress of technology, the problems of seepage prevention of storage yards, refuse landfills and tailing ponds of chemical and mining enterprises are effectively solved. Some vertical seepage prevention techniques, such as grouting curtains, mixing piles, steel sheet piles, vertical slotted plastic laying, and the like, are applied to engineering practice. The vertical slotting and plastic-paving technology is characterized in that a high-density polyethylene geomembrane is used as an anti-seepage material and is vertically inserted into an underground impervious layer to form a flexible vertical anti-seepage system. However, in the process, the joint of the geomembrane and the impermeable bed foundation soil or bedrock of the tank bottom cannot be well treated, and local leakage is easily caused.

Disclosure of Invention

Based on the technical problems in the background art, the invention provides an environment-friendly composite type anti-seepage flexible vertical isolation system which comprises an anti-seepage component for blocking pollutants in underground water and soil, wherein the anti-seepage component comprises a prefabricated fiber reinforced cement-based material or a magnesium carbide oxide-based material, two closed bolts with two reserved openings are formed on the surface of the anti-seepage component, the two anti-seepage components mutually clamp the same flexible anti-seepage wall body, and the flexible anti-seepage wall body is formed by a rectangular high-density polyethylene geomembrane.

Preferably, the material mixing ratio of the prefabricated anti-seepage surrounding member is type I, wherein the material mixing ratio of the type I is as follows: the mass ratio of the quick self-hardening cement to the magnesia to the natural sand to the fly ash to the water to the polycarboxylic water reducer is as follows: 0.94-1: 0-0.06: 0.6-0.8: 1.2-2.2: 0.56: 0.07-0.12, wherein the I type prefabricated anti-seepage component is internally doped with fibers, and the fibers account for 0.8-1.2% of the total volume.

Or the material mixing ratio of the prefabricated seepage-proof component can be type II: the mass ratio of the magnesium oxide, the fly ash, the water, the sodium hexametaphosphate and the polycarboxylic water reducer is as follows: 5-7: 3-5: 0.52: 0.06-0.12: 0.007-0.008, wherein the type II prefabricated penetration-preventing component is doped with fibers, and the fibers account for 0.8-1.2% of the total volume.

Preferably, the flexible impermeable wall has the following size ratios of length, width and height: 10: 0.5-1.5: 0.4-1.2, wherein the two close bolts are stainless steel double-headed stud bolts, and the bolt size is M10-M30 standard bolts.

Preferably, the anti-seepage component is composed of two prefabricated cuboid components, the rectangular high-density polyethylene geomembrane is embedded between the two prefabricated components, and the anti-seepage component is embedded in the underground impermeable layer.

Preferably, the cement is fast-hardening aluminate cement, the magnesium oxide is light magnesium oxide, the magnesium oxide is industrial-grade light magnesium oxide with the mass content of 70-88%, the river sand or basalt sand or gabby rock sand with the maximum particle size of the natural sand being smaller than 0.5mm, the fly ash is domestic 1-2-grade fly ash, the water is industrial tap water, the water reducing agent is a polycarboxylic water reducing agent, and the fiber can be polyvinyl alcohol and polypropylene fiber in synthetic fiber, can be sugarcane fiber or acetate fiber in artificial fiber, and can be cellulose fiber in natural fiber.

Preferably, in the type I prefabricated seepage-proofing component, the prefabrication method comprises the steps of adding the specific fiber of claim 5 into the prefabricated component mould of claim 3 after uniformly stirring the quick self-hardening cement, the magnesium oxide, the natural sand, the fly ash, the water and the polycarboxylate-type water reducing agent, quickly stirring and pouring the mixture into the prefabricated component mould of claim 3, curing the mixture at the temperature of 20-25 ℃ for 6 hours, demoulding and forming, and then curing for 2 days.

Preferably, in the II type prefabricated seepage-proofing component, the prefabrication method comprises the steps of uniformly stirring magnesium oxide, fly ash, water, sodium hexametaphosphate and a polycarboxylic water reducer, adding the specific fiber of claim 5, quickly stirring, pouring into the prefabricated component mould of claim 3, curing at 20-25 ℃ for 6 hours, demoulding and forming, and then carbonizing and curing in a carbonization box for 1-12 hours, wherein the concentration of carbon dioxide in the carbonization box is 60-98%, and the curing atmospheric pressure value is 1.2-5.8 MPa.

Preferably, the sodium hexametaphosphate and the polycarboxylic water reducer are respectively stirred in water to form a mixed solution 1 and a mixed solution 2, the stirring temperature of the mixed solution 1 is 65-110 degrees, and the stirring temperature of the mixed solution 2 is 10-20 degrees.

An installation method of an environment-friendly composite anti-seepage flexible vertical isolation system comprises the following steps:

s1: prefabricating a seepage-proof member: prefabricating anti-seepage members with corresponding quantity and length according to the requirements of an actual polluted site, and cutting a corresponding wide high-density polyethylene geomembrane;

s2: manufacturing a seepage prevention unit: inserting a single vertical high-density polyethylene geomembrane into the two prefabricated anti-seepage components, and fixing the prefabricated anti-seepage components and the vertical high-density polyethylene geomembrane by using stud threaded bolts to form a composite anti-seepage flexible vertical isolation unit;

s3: grooving: vertically slotting along the peripheral position of a constructed polluted site, excavating the slot bottom into an underground impervious layer, and adopting domestic commercial bentonite slurry with the mass ratio of 2% to protect the wall in the vertical slotting process;

s4: forming an anti-seepage system: inserting the impervious wall unit obtained in the step S2 into a vertical slot in the retaining wall slurry of the vertical slot, wherein the anti-seepage support part is placed at the bottom of the vertical slot;

s5: repeating the step S4 to enable each anti-seepage unit to be in close contact, wherein the high-density polyethylene geomembranes of the anti-seepage units are connected in a hot-melt butt joint mode;

s6: grouting: corresponding bentonite slurry is injected into the groove by adopting a pumping mode to cover the joint of the anti-winding member;

s7: backfilling: backfilling the trench with one or a mixture of sand and clay to remove the retaining wall mud.

For the I-type prefabricated seepage-prevention component, the pouring material of the seepage-prevention component is a high-ductility cement-based material, and the high-ductility cement-based material comprises the following components in percentage by mass:

21.1 to 27.87 percent of aluminate cement,

0 to 1.27 percent of magnesium oxide,

16.88 to 17.79 percent of natural sand,

35.58 to 46.41 percent of fly ash,

11.81 to 16.60 percent of water,

2.08 to 2.53 percent of polycarboxylic acid type water reducing agent,

and a PVA fiber, and a fiber,

wherein, the volume mixing amount of the PVA fiber is 0.8-1.2% of the total volume of the high ductility cement slurry.

As a preferred scheme, the mass ratio of the quick self-hardening cement to the magnesium oxide to the natural sand to the fly ash to the water to the polycarboxylic water reducer is as follows: 100: 6:80:220:56:12.

As a preferable scheme, the cement is quick-hardening aluminate cement, the average particle size of the natural sand is 0.75mm, the fly ash is domestic grade 1-2 fly ash, the magnesium oxide is light magnesium oxide, and the water reducing agent is a polycarboxylic water reducing agent.

Preferably, the magnesium oxide is industrial grade light magnesium oxide with the mass content of 70-88%, and the sand grain source is pyroxene sand crushed sand.

Preferably, the gabbros sand crushed sand is prepared by rolling by the following method:

the gabbro tailing sand is processed by a high-voltage pulse crusher to form a high voltage of 90-200 kV, then the high-voltage pulse crusher discharges the gabbro tailing sand to rock samples in water in a very short time through a high-voltage working electrode, the solid rock samples can be cracked along particle boundaries, inclusion bodies and different phases, and the cracked rock samples are screened for later use by a 35-mesh standard screen.

For a II-type prefabricated anti-infiltration member, the pouring material of the anti-infiltration member is a high-ductility magnesium carbide oxide-based material, and the high-ductility magnesium carbide oxide-based material comprises the following components in percentage by mass:

55.17-57.98% of magnesium oxide,

34.77 to 39.41 percent of fly ash,

4.41 to 6.49 percent of water,

0.70 to 0.95 percent of sodium hexametaphosphate,

0.06-0.08% of polycarboxylic acid type water reducing agent,

and a PVA fiber, and a fiber,

wherein, the volume mixing amount of the PVA fiber is 0.8-1.0 percent of the total volume of the high-ductility magnesium carbide oxide base material.

Preferably, the mass ratio of the magnesium oxide to the fly ash to the water to the sodium hexametaphosphate to the polycarboxylic water reducer is as follows: 700: 500:56:12:0.8.

As a preferable scheme, the magnesium oxide is 70-88% of light industrial grade light magnesium oxide, the fly ash is domestic 1-2 grade fly ash, the water reducing agent is a polycarboxylic water reducing agent, the concentration of the carbon dioxide for accelerating carbonization is 92%, and the curing atmospheric pressure value is 3.5 MPa.

Preferably, in the process of preparing the high-ductility magnesium carbide oxide-based material, water is stirred for three times, the water is firstly and independently mixed with sodium hexametaphosphate, is secondly and independently mixed with a polycarboxylic water reducer, and is thirdly mixed with a mixture of magnesium oxide and fly ash, wherein the mass ratio of the water added in the first stirring, the second stirring and the third stirring is 2:2: 3.

And for the manufactured anti-seepage unit, the anti-seepage unit consists of two symmetrical prefabricated anti-seepage components and a pair of vertical high-density polyethylene geomembranes, wherein the high-density polyethylene geomembranes are inserted into the two prefabricated anti-seepage components and are fixed by using threaded studs.

Preferably, the prefabricated anti-infiltration penetration component has the following dimensional proportions of length (L), width (W) and height (H): 10: 0.5-1.5: 0.4-1.2.

Preferably, the length of the anti-seepage component is 2 meters, the width is 10cm, the height is 8cm, and the single-width longitudinal length of the high-density polyethylene geomembrane is 2.2 meters.

As a preferred scheme, the high-density polyethylene geomembrane adopts a double-seam hot-melt welding process, namely the cut-off high-density polyethylene geomembrane is connected in a hot-melt butt joint mode, two sides needing to be lapped are subjected to hot melting, the hot melting temperature is 100 ℃ and 150 ℃, the high-density polyethylene geomembrane is quickly butted after reaching the temperature, the butt joint parts of the two sides are provided with hollow cavities, the hollow cavities are provided with compressed air, the butt joint parts of the left side and the right side of each hollow cavity are welding seams, welding is carried out at the welding seams, the welding temperature is 450 ℃ and 480 ℃, and the welding process needs to ensure the integrity of welding points.

Has the advantages that: compared with the prior art of slotting and plastic laying, the environment-friendly composite anti-seepage flexible vertical isolation system provided by the embodiment of the invention has the following advantages: the system can solve the leakage problem caused by poor contact between the geomembrane and the impervious bed at the bottom of the tank, can meet the requirement of maintaining the seepage-proofing property under extreme earthquakes or large-scale geological activities, adopts environment-friendly material magnesium oxide, is formed by accelerating components by a carbonization method, and can achieve the positive effects of comprehensively utilizing the environment-friendly material, absorbing carbon dioxide, efficiently producing the anti-seepage material and having high ductility.

Drawings

FIG. 1 is a drawing showing the results of tensile deformation and permeability coefficient of the type I and type II environmental protection composite wind-proof component according to the present invention;

FIG. 2 is a diagram showing the relationship between the tensile strength and the tensile strength of the type I and type II environmental protection composite anti-winding members under the condition of simulating the tensile failure caused by earthquake;

FIG. 3 is a diagram of a vertical partition wall system for a method of manufacturing and installing an environmentally friendly composite type anti-seepage flexible vertical partition system according to the present invention;

FIG. 4 is a schematic diagram of an application section of a vertical partition wall system field of the method for manufacturing and installing the environment-friendly composite type anti-seepage flexible vertical partition wall system provided by the invention.

In the figure: 1 anti-seepage member, 2 flexible anti-seepage wall, 3 close bolt.

Detailed Description

The present invention will be further illustrated with reference to the following specific examples.

Referring to fig. 1-4, the invention provides an environment-friendly composite type anti-seepage flexible vertical isolation system, which comprises an anti-seepage component for blocking pollutants in groundwater and soil, wherein the anti-seepage component comprises a prefabricated fiber reinforced cement-based material or a magnesium carbide oxide-based material, two closed bolts with two reserved openings are formed on the surface of the anti-seepage component, two anti-seepage components mutually clamp a same flexible anti-seepage wall body, and the flexible anti-seepage wall body is formed by a rectangular high-density polyethylene geomembrane.

Preferably, the material mixing ratio of the prefabricated anti-seepage surrounding member is type I, wherein the material mixing ratio of the type I is as follows: the mass ratio of the quick self-hardening cement to the magnesia to the natural sand to the fly ash to the water to the polycarboxylic water reducer is as follows: 0.94-1: 0-0.06: 0.6-0.8: 1.2-2.2: 0.56: 0.07-0.12, wherein the I type prefabricated anti-seepage component is internally doped with fibers, and the fibers account for 0.8-1.2% of the total volume.

Or the material mixing ratio of the prefabricated seepage-proof component can be type II: the mass ratio of the magnesium oxide, the fly ash, the water, the sodium hexametaphosphate and the polycarboxylic water reducer is as follows: 5-7: 3-5: 0.52: 0.06-0.12: 0.007-0.008, wherein the type II prefabricated penetration-preventing component is doped with fibers, and the fibers account for 0.8-1.2% of the total volume.

Preferably, the flexible impermeable wall has the following size ratios of length, width and height: 10: 0.5-1.5: 0.4-1.2, wherein the two close bolts are stainless steel double-headed stud bolts, and the bolt size is M10-M30 standard bolts.

Preferably, the anti-seepage component is composed of two prefabricated cuboid components, the rectangular high-density polyethylene geomembrane is embedded between the two prefabricated components, and the anti-seepage component is embedded in the underground impermeable layer.

Preferably, the cement is fast-hardening aluminate cement, the magnesium oxide is light magnesium oxide, the magnesium oxide is industrial-grade light magnesium oxide with the mass content of 70-88%, the river sand or basalt sand or gabby rock sand with the maximum particle size of the natural sand being smaller than 0.5mm, the fly ash is domestic 1-2-grade fly ash, the water is industrial tap water, the water reducing agent is a polycarboxylic water reducing agent, and the fiber can be polyvinyl alcohol and polypropylene fiber in synthetic fiber, can be sugarcane fiber or acetate fiber in artificial fiber, and can be cellulose fiber in natural fiber.

Preferably, in the type I prefabricated seepage-proofing component, the prefabrication method comprises the steps of adding the specific fiber of claim 5 into the prefabricated component mould of claim 3 after uniformly stirring the quick self-hardening cement, the magnesium oxide, the natural sand, the fly ash, the water and the polycarboxylate-type water reducing agent, quickly stirring and pouring the mixture into the prefabricated component mould of claim 3, curing the mixture at the temperature of 20-25 ℃ for 6 hours, demoulding and forming, and then curing for 2 days.

Preferably, in the II type prefabricated seepage-proofing component, the prefabrication method comprises the steps of uniformly stirring magnesium oxide, fly ash, water, sodium hexametaphosphate and a polycarboxylic water reducer, adding the specific fiber of claim 5, quickly stirring, pouring into the prefabricated component mould of claim 3, curing at 20-25 ℃ for 6 hours, demoulding and forming, and then carbonizing and curing in a carbonization box for 1-12 hours, wherein the concentration of carbon dioxide in the carbonization box is 60-98%, and the curing atmospheric pressure value is 1.2-5.8 MPa.

Preferably, the sodium hexametaphosphate and the polycarboxylic water reducer are respectively stirred in water to form a mixed solution 1 and a mixed solution 2, the stirring temperature of the mixed solution 1 is 65-110 degrees, and the stirring temperature of the mixed solution 2 is 10-20 degrees.

An installation method of an environment-friendly composite anti-seepage flexible vertical isolation system comprises the following steps:

s1: prefabricating a seepage-proof member: prefabricating anti-seepage members with corresponding quantity and length according to the requirements of an actual polluted site, and cutting a corresponding wide high-density polyethylene geomembrane;

s2: manufacturing a seepage prevention unit: inserting a single vertical high-density polyethylene geomembrane into the two prefabricated anti-seepage components, and fixing the prefabricated anti-seepage components and the vertical high-density polyethylene geomembrane by using stud threaded bolts to form a composite anti-seepage flexible vertical isolation unit;

s3: grooving: vertically slotting along the peripheral position of a constructed polluted site, excavating the slot bottom into an underground impervious layer, and adopting domestic commercial bentonite slurry with the mass ratio of 2% to protect the wall in the vertical slotting process;

s4: forming an anti-seepage system: inserting the impervious wall unit obtained in the step S2 into a vertical slot in the retaining wall slurry of the vertical slot, wherein the anti-seepage support part is placed at the bottom of the vertical slot;

s5: repeating the step S4 to enable each anti-seepage unit to be in close contact, wherein the high-density polyethylene geomembranes of the anti-seepage units are connected in a hot-melt butt joint mode;

s6: grouting: corresponding bentonite slurry is injected into the groove by adopting a pumping mode to cover the joint of the anti-winding member;

s7: backfilling: backfilling the trench with one or a mixture of sand and clay to remove the retaining wall mud.

The prefabricated seepage-proof component of the I type and the II type comprises the following components in percentage by mass:

i type prefabricated seepage-proof component:

21.1 to 27.87 percent of aluminate cement,

0 to 1.27 percent of magnesium oxide,

16.88 to 17.79 percent of natural sand,

35.58 to 46.41 percent of fly ash,

11.81 to 16.60 percent of water,

2.08 to 2.53 percent of polycarboxylic acid type water reducing agent,

and PVA fiber, the volume mixing amount of the PVA fiber is 0.8-1.2% of the total volume of the high ductility cement slurry.

Type II prefabricated seepage-proofing component:

55.17-57.98% of magnesium oxide,

34.77 to 39.41 percent of fly ash,

4.41 to 6.49 percent of water,

0.70 to 0.95 percent of sodium hexametaphosphate,

0.06-0.08% of polycarboxylic acid type water reducing agent,

and PVA fiber, the volume mixing amount of the PVA fiber is 0.8-1.0% of the total volume of the high-ductility magnesium carbide oxide-based material.

The process for preparing the I-type composite anti-seepage component comprises the following steps: uniformly mixing solid materials (aluminate cement, magnesium oxide, natural sand and fly ash), adding water, stirring for the first time, adding PVA (polyvinyl acetate) fibers and water, stirring for the second time to obtain high-ductility fiber pulp, and pouring the prepared high-ductility fiber pulp into a mold through pouring equipment to form a prefabricated part.

The process for preparing the II-type composite anti-seepage component comprises the following steps: stirring sodium hexametaphosphate and water for the first time, setting the stirring temperature to be 65 degrees, forming a mixed solution 1, then stirring a polycarboxylic water reducer and water for the second time, forming a mixed solution 2, finally mixing and stirring solid materials (magnesium oxide and fly ash) with the solution 1 and the solution 2 for the third time, obtaining high-ductility fiber slurry, pouring the high-ductility fiber slurry into a mold, and waiting for 6 hours for carbonization and maintenance to form a prefabricated part.

Examples analysis

Experiments prove that the environment-friendly composite type anti-seepage flexible vertical isolation system has good seepage-proofing property and high ductility.

Example 1

The process for preparing the I-type composite anti-seepage component comprises the following steps: uniformly mixing solid materials (aluminate cement, magnesium oxide, natural sand and fly ash), adding water, stirring for the first time, adding PVA fibers and water, stirring for the second time to obtain high-ductility fiber slurry, pouring the prepared high-ductility fiber slurry into a mold through pouring equipment to form a prefabricated part, wherein the length, height and thickness of the prefabricated part are respectively 2m 10cm 8 m.

In this embodiment, the I-type composite anti-seepage component comprises the following components in percentage by mass:

23.52 percent of aluminate cement,

0 percent of magnesium oxide,

17.79 percent of natural sand,

40.82 percent of fly ash,

16.24 percent of water,

2.18 percent of polycarboxylic acid type water reducing agent,

the volume mixing amount of the fiber PVA is 0.8-1.2% of the total volume of the high ductility cement slurry.

Example 2

The procedure for preparing a prefabricated penetration-preventing member was the same as in example 1, except that:

in this embodiment, the I-type composite anti-seepage component comprises the following components in percentage by mass:

23.52 percent of aluminate cement,

1.22 percent of magnesium oxide,

17.79 percent of natural sand,

39.05 percent of fly ash,

16.24 percent of water,

2.18 percent of polycarboxylic acid type water reducing agent,

the volume mixing amount of the fiber PVA is 0.8-1.2% of the total volume of the high ductility cement slurry.

Example 3

The procedure for preparing a prefabricated penetration-preventing member was the same as in example 1, except that:

in this embodiment, the I-type composite anti-seepage component comprises the following components in percentage by mass:

23.52 percent of aluminate cement,

2.44 percent of magnesium oxide,

17.79 percent of natural sand,

37.28 percent of fly ash,

16.24 percent of water,

2.18 percent of polycarboxylic acid type water reducing agent,

the volume mixing amount of the fiber PVA is 0.8-1.2% of the total volume of the high ductility cement slurry.

Example 4

The process for preparing the II-type composite anti-seepage component comprises the following steps: stirring sodium hexametaphosphate and water for the first time, setting the stirring temperature to be 65 degrees, forming a mixed solution 1, then stirring the polycarboxylate-type water reducing agent and water for the second time, forming a mixed solution 2, finally mixing and stirring solid materials (magnesium oxide and fly ash) with the solution 1 and the solution 2 for the third time, obtaining high-ductility fiber slurry, and pouring the high-ductility fiber slurry into a mold.

In this embodiment, the type II composite type anti-seepage component includes the following components by mass percent:

57.98 percent of magnesium oxide,

34.41 percent of fly ash,

6.58 percent of water,

0.95 percent of sodium hexametaphosphate,

0.08 percent of polycarboxylic acid type water reducing agent,

the volume mixing amount of the fiber PVA is 0.8-1.0 percent of the total volume of the high-ductility magnesium carbide oxide base material.

In this example, the carbonization time was 1 hour, and the carbonization pressure was 2.5 MPa.

Example 5

The procedure for preparing a prefabricated penetration-preventing member was the same as in example 4, except that: in this example, the carbonization time was 6 hours and the carbonization pressure was 2.5 MP.

Example 6

The procedure for preparing a prefabricated penetration-preventing member was the same as in example 1, except that:

in this embodiment, the type II composite type anti-seepage component includes the following components by mass percent:

55.17 percent of magnesium oxide,

39.12 percent of fly ash,

4.41 percent of water,

0.70 percent of sodium hexametaphosphate,

0.06 percent of polycarboxylic acid type water reducing agent,

the volume mixing amount of the fiber PVA is 0.8-1.0 percent of the total volume of the high-ductility magnesium carbide oxide base material.

In this example, the carbonization time was 1 hour, and the carbonization pressure was 2.5 MP.

Example 7

The procedure for preparing a prefabricated penetration-preventing member was the same as in example 6, except that: in this example, the carbonization time was 6 hours and the carbonization pressure was 2.5 MP.

Seepage prevention test

The test process comprises the following steps: the test is carried out by adopting the standard of the test method of the long-term performance and the durability of the common concrete with the national label GB-T50082-2009.

The test results are shown in FIG. 1, and the impermeability requirement can be achieved without cracking (10)^-9m/s) can meet international standards and is used for retarding the migration and seepage prevention of pollutants in polluted sites and mining areas.

As can be seen from FIG. 1, increasing the amount of magnesium oxide can effectively reduce the permeability coefficient of the prefabricated anti-bypass structure I, and the effect is more obvious as the cracking width is larger, the mechanism is that magnesium oxide can be hydrated to form an expansion body to fill cracking cracks, and can be continuously hydrated to form hydration products such as hydrated magnesium silicate and the like, so that the permeability coefficient is reduced, and the change rule is as follows: the permeability coefficients were sized for example 3 < example 2 < example 1 under the same cracking conditions.

For type II prefabricated barrier components, increasing the magnesia content and increasing the carbonization time reduces the permeability coefficient, which is scaled up to example 7 < example 6 < example 5 < example 4 under the same cracking conditions.

High ductility test

The test process comprises the following steps: the test is carried out by adopting the standard of the ordinary concrete mechanical property test method with the national standard GB/T50081-2002.

The test results are shown in fig. 2, and the results show that the type I and type II anti-infiltration members have high ductility similar to that of a metal material, and the maximum deformation amount can reach 6.2%.

For the I-type anti-seepage component, the mixing amount of magnesium oxide is increased, the tensile strength of the component can be enhanced, the tensile amount is slightly influenced, and the width of a crack is effectively controlled, namely the tensile resistance is arranged to be that the formula is that example 3 is larger than example 2, and the formula is that the formula is larger than example 1.

For the II type prefabricated part, the magnesium oxide mixing amount is increased, so that the stretching amount of the prefabricated part and the tensile strength of the prefabricated part can be improved; the carbonization time of the prefabricated part is increased, the carbon dioxide absorption amount is increased, namely, the environmental protection benefit is improved, but the tensile amount of the weak prefabricated part is weakened, and the tensile strength of the prefabricated part is improved, namely, the tensile resistance is arranged to be greater than that of example 4, greater than that of example 5, greater than that of example 6 and greater than that of example 7; tensile strength was ranked as example 5 > example 7 > example 4 > example 6.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.