Multi-layer composite long-acting durable anti-seepage construction process

Abstract

The invention relates to the technical field of anti-seepage membrane construction, in particular to a multi-layer composite long-acting durable anti-seepage construction process which comprises the following steps: preparation before construction: providing a laying and welding plane layout diagram, checking the quality of a construction site and an anti-seepage membrane, and ensuring that construction equipment and materials are qualified; the anti-seepage film is cut, transported and loaded according to the design requirement, the film is smoothly and firmly attached during laying, the length of expansion caused by heat and contraction caused by cold is reserved, and materials are prevented from being damaged; a double-welding-seam overlap welding process is adopted, the surface is cleaned before welding, a welding machine gun head is kept vertical, the change of the overlap width is paid attention to, and an air pressure leak detection test is conducted after welding; anchoring an impermeable membrane: excavating and flattening an anchoring groove, wherein the compaction degree of backfill soil is not less than 95%; according to temporary measures in the construction process, ballast measures are adopted to prevent the impermeable film from being blown up by wind, construction records are made, and by optimizing the construction process of the HDPE impermeable film and improving the welding technology and the anchoring technology, the construction quality of the impermeable film is effectively improved, and the construction cost is reduced.

Description

Technical Field

[0001] The invention relates to the field of anti-seepage membrane construction, and in particular to a multi-layer composite long-acting and durable anti-seepage construction process, which is particularly suitable for projects requiring anti-seepage treatment, such as landfills, sewage treatment pools, and water conservancy projects. Background Art

[0002] Traditional anti-seepage construction technology mainly uses a single material (such as HDPE anti-seepage membrane) for construction. Although it can meet the anti-seepage needs to a certain extent, it has problems such as short service life and unstable construction quality under complex environmental conditions (such as high temperature, low temperature, chemical corrosion, mechanical damage, etc.). In addition, the anti-seepage system of a single material has limitations in dealing with long-term leakage risks and is difficult to meet increasingly stringent environmental protection and engineering requirements.

[0003] HDPE anti-seepage membrane is widely used in various anti-seepage projects due to its excellent anti-seepage performance, chemical stability and durability. However, there are many problems in the construction process of traditional HDPE anti-seepage membrane, such as unstable welding quality, low construction efficiency, and susceptibility to environmental factors. These problems seriously affect the overall quality and service life of the anti-seepage project.

[0004] Therefore, a multi-layer composite long-term durable anti-seepage construction process is needed to improve the above problems. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a multi-layer composite long-term durable anti-seepage construction process, which adopts a multi-layer laying process to effectively improve the construction quality of the anti-seepage membrane and ensure the durability and reliability of the anti-seepage system.

[0006] To achieve this technical purpose, the present invention adopts the following scheme: A multi-layer composite long-term durable anti-seepage construction process, comprising the following steps: S1. Preparation before construction S1.1. According to the topography and design requirements of the construction site, formulate a detailed plan for laying and welding of the anti-seepage membrane, and rationally plan the laying direction and joint position of the anti-seepage membrane; Specifically, before laying the HDPE anti-seepage membrane, the construction unit needs to provide a detailed laying and welding plan, reasonably select the laying direction, reduce the number of joints, and avoid transverse joints on slopes with a slope greater than 10% and within 1.5m of the slope foot; S1.2. Conduct a comprehensive inspection of the construction site to ensure that the foundation surface is flat and free of sharp particles and hard debris. At the same time, conduct a strict inspection of the quality of the anti-seepage membrane and only lay it after confirmation; Specifically, invite the owner and the supervision engineer to conduct a comprehensive inspection of the construction site to ensure that the foundation surface is flat, free of sharp particles and hard debris, and that there is no harmful debris within a depth of 25mm on the surface; at the same time, strictly inspect the quality of the anti-seepage membrane, including various performance indicators, whether there are bubbles, holes, and wrinkles on the surface, and only after confirmation can it be laid; Construction equipment, machinery and HDPE anti-seepage membrane materials shall be inspected before construction to ensure the normal operation of the equipment, the appearance of the materials is not damaged, and the materials are approved by the supervising engineer.

[0007] S2. Installation of anti-seepage membrane S2.1. The bottom HDPE anti-seepage membrane is laid, cut and transported according to the design requirements to ensure smooth and tight laying, and reserve the length for thermal expansion and contraction; double weld lap welding is adopted for welding, and air pressure leak test is carried out after welding; Specifically, the HDPE anti-seepage membrane should be laid smoothly and firmly, with wrinkles minimized, and ballasted and anchored in time after laying; the anti-seepage membrane should be laid with the smooth surface facing up and the rough surface facing down, and the length of thermal expansion and contraction should be reserved during the construction process to adapt to the influence of climatic factors; the welding form adopts double weld lap welding, the weld lap width should not be less than 100mm, and the welding connection strength should not be less than the parent material strength. Extrusion welding should be used when repairing or in places where double weld equipment cannot reach; in addition, the construction site should have sufficient welding equipment to ensure continuous welding construction; after welding, each welder should take a sample every 150m of weld length to test the weld strength; the double-track welded anti-seepage membrane should be subjected to air pressure leak detection test in the closed space formed between the two welds; S2.2. Lay high-strength geotextile on the bottom HDPE anti-seepage membrane with an overlap width of not less than 150mm, fix it by suturing, and perform secondary anchoring; Specifically, when adjusting the overlap width of the material during the laying process, the connected parts must not be damaged; when adjusting the position of the anti-seepage membrane after laying, the installed anti-seepage membrane must not be damaged; S2.3, lay the modified HDPE protective layer on the geotextile layer, use the monorail extrusion welding process, and perform vacuum test after welding; Specifically, before extrusion welding, the upper and lower films are bonded with hot air, and the oxide layer at the welding position is removed with a grinder, and the grinding width is consistent with the extrusion welding width; after welding, samples are taken once every 150m of weld length for each welding machine to test the weld strength; extrusion welding uses vacuum testing or electric spark testing; In addition, it should be noted that during the laying process, the geotechnical materials should be prevented from being damaged by loading and unloading activities, high temperature, and chemical leakage; the laying tools should not cause damage to the anti-seepage membrane, and the construction machinery and equipment should not cause obvious scratches on the anti-seepage membrane and damage to the base surface; Before welding, clean the dust and dirt on the surface of the anti-seepage membrane and clean the welding edge; keep the welding gun head perpendicular to the welding plane and maintain a certain pressure during welding, pay attention to the change of lap width, and when double-track fusion welding, the lap width of the extruded weld should not be less than 75mm, and the welding connection strength should not be less than the strength of the parent material.

[0008] S3, Anti-seepage membrane anchoring The anchor trench is excavated and leveled, and the backfill soil is compacted layer by layer using a small compactor, with a compaction degree of not less than 95%; Specifically, the soil at the bottom of the anchor trench must not be disturbed during excavation, the bottom of the trench must be flat and free of loose soil, and the slope of the trench wall must meet the design requirements; before backfilling the anchor trench, the bottom of the trench must not be soaked by water, and accumulated water should be discharged in a timely manner; backfilling of the anchor trench should be carried out in a timely manner, the soil quality of the backfill soil must meet the design requirements, and a small compactor should be used to compact it in layers, with a compaction degree of not less than 95%.

[0009] S4. Special parts treatment At special locations such as the intersection of slopes and bends, the "inverted trapezoidal" cutting or "T-shaped" welding process is used according to the actual situation on site to ensure that the anti-seepage membrane fits tightly against the base. For places where normal welding construction cannot be used, special processes are used for treatment and secondary reinforcement is carried out.

[0010] S5. Quality inspection and acceptance During the construction process, self-inspection, re-inspection and final inspection are carried out on each process to ensure the construction quality. After acceptance, the on-site data form is filled out and retained.

[0011] Specifically, during the construction process, each process is self-inspected, re-inspected and finally inspected to ensure construction quality; weld quality inspection uses vacuum method, air pressure method, electric spark test and destructive test to ensure weld strength and sealing; after acceptance, fill in and retain the on-site data form as a valid basis for completion acceptance.

[0012] Preferably, during welding, the overlap width of the double-track fusion welding is not less than 100 mm, the overlap width of the extrusion weld is not less than 75 mm, and the welding connection strength is not less than the strength of the parent material.

[0013] Preferably, the soil at the bottom of the anchoring trench shall not be disturbed during excavation of the anchoring trench, the trench bottom shall be flat and free of loose soil, and the accumulated water shall be discharged in time before backfilling the anchoring trench, and the backfill soil shall be compacted layer by layer using a small compactor, with a compaction degree of not less than 95%.

[0014] Preferably, the present invention requires sufficient temporary ballast during the construction process to prevent the laid anti-seepage membrane from being blown away by strong winds. In the event of strong winds, the anti-seepage membrane must be temporarily anchored and the installation work must be suspended. Records should be kept during the construction process and submitted to the owner for filing and future reference.

[0015] Compared with the prior art, the present invention has the following beneficial effects: In the present invention, by optimizing the construction process of the HDPE anti-seepage membrane, improving the welding process and anchoring technology, the construction quality of the anti-seepage membrane is effectively improved and the construction cost is reduced. At the same time, by reserving the thermal expansion and contraction length, cleaning the welding edge, adopting the air pressure leak test and other measures, the adaptability of the anti-seepage membrane in complex environments is enhanced, the service life of the anti-seepage project is extended, and significant economic and social benefits are achieved.

[0016] In the present invention, by adopting a multi-layer composite material structure and optimizing the construction process, the durability and reliability of the anti-seepage system are significantly improved. The bottom HDPE anti-seepage membrane provides a basic anti-seepage function, the middle reinforcement layer enhances the overall strength of the system, and the upper protective layer effectively resists the erosion of external environmental factors. In addition, the construction process of the present invention is simple and easy, the construction quality is stable, the maintenance cost is low, and it has significant economic and social benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The figure is a schematic diagram of the construction steps of the single-layer anti-seepage membrane of the present invention. DETAILED DESCRIPTION

[0018] In order to fully understand the purpose, features and effects of the present invention, the present invention is described in detail through the following specific implementation methods, but the present invention is not limited thereto.

[0019] See also Figure 1 The present invention provides a multi-layer composite long-term durable anti-seepage construction process, comprising the following steps: S1. Preparation before construction S1.1. According to the topography and design requirements of the construction site, formulate a detailed plan for laying and welding of the anti-seepage membrane, and rationally plan the laying direction and joint position of the anti-seepage membrane; Specifically, before laying the HDPE anti-seepage membrane, the construction unit needs to provide a detailed laying and welding plan, reasonably select the laying direction, reduce the number of joints, and avoid transverse joints on slopes with a slope greater than 10% and within 1.5m of the slope foot; S1.2. Conduct a comprehensive inspection of the construction site to ensure that the foundation surface is flat and free of sharp particles and hard debris. At the same time, conduct a strict inspection of the quality of the anti-seepage membrane and only lay it after confirmation; Specifically, invite the owner and the supervision engineer to conduct a comprehensive inspection of the construction site to ensure that the foundation surface is flat, free of sharp particles and hard debris, and that there is no harmful debris within a depth of 25mm on the surface; at the same time, strictly inspect the quality of the anti-seepage membrane, including various performance indicators, whether there are bubbles, holes, and wrinkles on the surface, and only after confirmation can it be laid; Construction equipment, machinery and HDPE anti-seepage membrane materials shall be inspected before construction to ensure the normal operation of the equipment, the appearance of the materials is not damaged, and the materials are approved by the supervising engineer.

[0020] S2. Installation of anti-seepage membrane S2.1. The bottom HDPE anti-seepage membrane is laid, cut and transported according to the design requirements to ensure smooth and tight laying, and reserve the length for thermal expansion and contraction; double weld lap welding is adopted for welding, and air pressure leak test is carried out after welding; Specifically, the HDPE anti-seepage membrane should be laid smoothly and firmly, with wrinkles minimized, and ballasted and anchored in time after laying; the anti-seepage membrane should be laid with the smooth surface facing up and the rough surface facing down, and the length of thermal expansion and contraction should be reserved during the construction process to adapt to the influence of climatic factors; the welding form adopts double weld lap welding, the weld lap width should not be less than 100mm, and the welding connection strength should not be less than the parent material strength. Extrusion welding should be used when repairing or in places where double weld equipment cannot reach; in addition, the construction site should have sufficient welding equipment to ensure continuous welding construction; after welding, each welder should take a sample every 150m of weld length to test the weld strength; the double-track welded anti-seepage membrane should be subjected to air pressure leak detection test in the closed space formed between the two welds; S2.2. Lay high-strength geotextile on the bottom HDPE anti-seepage membrane with an overlap width of not less than 150mm, fix it by suturing, and perform secondary anchoring; Specifically, when adjusting the overlap width of the material during the laying process, the connected parts must not be damaged; when adjusting the position of the anti-seepage membrane after laying, the installed anti-seepage membrane must not be damaged; S2.3, lay the modified HDPE protective layer on the geotextile layer, use the monorail extrusion welding process, and perform vacuum test after welding; Specifically, before extrusion welding, the upper and lower films are bonded with hot air, and the oxide layer at the welding position is removed with a grinder, and the grinding width is consistent with the extrusion welding width; after welding, samples are taken once every 150m of weld length for each welding machine to test the weld strength; extrusion welding uses vacuum testing or electric spark testing; In addition, it should be noted that during the laying process, the geotechnical materials should be prevented from being damaged by loading and unloading activities, high temperature, and chemical leakage; the laying tools should not cause damage to the anti-seepage membrane, and the construction machinery and equipment should not cause obvious scratches on the anti-seepage membrane and damage to the base surface; Before welding, clean the dust and dirt on the surface of the anti-seepage membrane and clean the welding edge; keep the welding gun head perpendicular to the welding plane and maintain a certain pressure during welding, pay attention to the change of lap width, and when double-track fusion welding, the lap width of the extruded weld should not be less than 75mm, and the welding connection strength should not be less than the strength of the parent material.

[0021] S3, Anti-seepage membrane anchoring The anchor trench is excavated and leveled, and the backfill soil is compacted layer by layer using a small compactor, with a compaction degree of not less than 95%; Specifically, the soil at the bottom of the anchor trench must not be disturbed during excavation, the bottom of the trench must be flat and free of loose soil, and the slope of the trench wall must meet the design requirements; before backfilling the anchor trench, the bottom of the trench must not be soaked by water, and accumulated water should be discharged in a timely manner; backfilling of the anchor trench should be carried out in a timely manner, the soil quality of the backfill soil must meet the design requirements, and a small compactor should be used to compact it in layers, with a compaction degree of not less than 95%.

[0022] S5. Special parts treatment At special locations such as the intersection of slopes and bends, the "inverted trapezoidal" cutting or "T-shaped" welding process is used according to the actual situation on site to ensure that the anti-seepage membrane fits tightly against the base. For places where normal welding construction cannot be used, special processes are used for treatment and secondary reinforcement is carried out.

[0023] S6. Quality inspection and acceptance During the construction process, self-inspection, re-inspection and final inspection are carried out on each process to ensure the construction quality. After acceptance, the on-site data form is filled out and retained.

[0024] Specifically, during the construction process, each process is self-inspected, re-inspected and finally inspected to ensure construction quality; weld quality inspection uses vacuum method, air pressure method, electric spark test and destructive test to ensure weld strength and sealing; after acceptance, fill in and retain the on-site data form as a valid basis for completion acceptance.

[0025] Furthermore, there must be sufficient temporary ballast during the construction process to prevent the installed anti-seepage membrane from being blown away by strong winds. In the event of strong winds, the anti-seepage membrane must be temporarily anchored and the installation work must be suspended. Records should be kept during the construction process and submitted to the owner for filing and future reference.

[0026] Example 1: Multi-layer composite anti-seepage construction of landfill S1.1. Before construction, a detailed plan for laying and welding the impermeable membrane shall be drawn up according to the topography and design requirements of the landfill, and the laying direction and joint position of the impermeable membrane shall be reasonably planned.

[0027] S1.2. Invite the owner and the supervising engineer to conduct a comprehensive inspection of the construction site to ensure that the foundation surface is flat and free of sharp particles and hard debris. At the same time, strictly check the quality of the anti-seepage materials and lay them after confirmation.

[0028] S2.1. When laying the bottom HDPE anti-seepage membrane, cut the membrane and transport it according to the design requirements to ensure smooth and tight laying, and reserve the length for thermal expansion and contraction. The welding adopts double weld lap welding technology, and the air pressure leak test is carried out after welding.

[0029] S2.2. Lay high-strength geotextile on the bottom HDPE anti-seepage membrane with an overlap width of not less than 150mm. Fix it by suturing and perform secondary anchoring.

[0030] S2.3. Lay a modified HDPE protective layer on the middle reinforcement layer, adopt a single-track extrusion welding process, and perform a vacuum test after welding.

[0031] S3. The anchor trench is excavated and leveled, and the backfill soil is compacted layer by layer using a small compactor, with a compaction degree of not less than 95%. Vegetation soil is covered on the surface of the anti-seepage system to prevent mechanical damage and ultraviolet erosion.

[0032] S4. At the intersection of slopes and bends, according to the actual situation on site, use "inverted trapezoidal" cutting or "T-shaped" welding technology to ensure that the anti-seepage membrane fits tightly to the base.

[0033] S5. During the construction process, there must be sufficient temporary ballast to prevent the installed anti-seepage membrane from being blown away by strong winds. In the event of strong winds, the anti-seepage membrane must be temporarily anchored and the installation work must be suspended.

[0034] S6. During the construction process, self-inspection, re-inspection and final inspection shall be carried out on each process to ensure the construction quality. After acceptance, fill in and keep the on-site data form.

[0035] Through the above construction technology, the landfill's anti-seepage system has excellent durability and reliability, its service life is significantly extended, and it meets the expected design requirements.

[0036] Finally, it should be noted that the above are only preferred embodiments of the present invention. Of course, those skilled in the art can make changes and modifications to the present invention. If these modifications and variations fall within the scope of the claims of the present invention and their equivalent technologies, they should be considered to be within the scope of protection of the present invention.

Claims

1. A multi-layer composite long-term durable anti-seepage construction process, characterized in that: The following steps are involved: S1. Preparation before construction S1.

1. According to the topography and design requirements of the construction site, formulate a detailed plan for laying and welding the anti-seepage membrane, and rationally plan the laying direction and joint position of the anti-seepage membrane; S1.

2. Conduct a comprehensive inspection of the construction site to ensure that the foundation surface is flat and free of sharp particles and hard debris. At the same time, conduct a strict inspection of the quality of the anti-seepage membrane and only lay it after confirmation; S2. Installation of anti-seepage membrane S2.

1. The bottom HDPE anti-seepage membrane is laid, cut and transported according to the design requirements to ensure smooth and tight laying, and reserve the length for thermal expansion and contraction; double weld lap welding is adopted for welding, and air pressure leak test is carried out after welding; S2.

2. Lay high-strength geotextile on the bottom HDPE anti-seepage membrane with an overlap width of not less than 150mm, fix it by suturing, and perform secondary anchoring; S2.3, lay the modified HDPE protective layer on the geotextile layer, use the monorail extrusion welding process, and perform vacuum test after welding; S3, Anti-seepage membrane anchoring The anchor trench is excavated and leveled, and the backfill soil is compacted layer by layer using a small compactor, with a compaction degree of not less than 95%; S4. Special parts treatment At the intersection of slopes and bends, according to the actual situation on site, the "inverted trapezoidal" cutting or "T-shaped" welding process is used to ensure that the anti-seepage membrane fits tightly with the base; S5. Quality inspection and acceptance During the construction process, self-inspection, re-inspection and final inspection are carried out on each process to ensure construction quality. After acceptance, the on-site data form is filled out and retained.

2. The multi-layer composite long-term durable anti-seepage construction process according to claim 1 is characterized in that: During welding, the lap width of double welds shall not be less than 100mm, the lap width of extrusion welds shall not be less than 75mm, and the welding connection strength shall not be less than the strength of the parent material.

3. The multi-layer composite long-term durable anti-seepage construction process according to claim 1 is characterized in that: During the excavation of the anchoring trench, the soil at the bottom of the trench must not be disturbed, the trench bottom must be flat and there must be no loose soil; before backfilling the anchoring trench, the accumulated water must be drained in time, and the backfill soil must be compacted layer by layer using a small compactor, with a compaction degree of not less than 95%.

4. The multi-layer composite long-term durable anti-seepage construction process according to claim 1 is characterized in that: During the construction process, there must be sufficient temporary ballast to prevent the laid anti-seepage membrane from being blown away by strong winds.

Images