WO2020093551A1

WO2020093551A1 - Geomembrane construction method

Info

Publication number: WO2020093551A1
Application number: PCT/CN2018/122438
Authority: WO
Inventors: 王洋; 齐长青; 刘勇; 罗彬�; 田素芳; 黄志亮; 郝海靖; 张道利; 郎洁
Original assignee: 北京高能时代环境技术股份有限公司
Priority date: 2018-11-06
Filing date: 2018-12-20
Publication date: 2020-05-14
Also published as: AU2019101070A4; CN109183854A

Abstract

A geomembrane construction method, which relates to the technical field of anti-seepage material construction methods. The geomembrane construction method comprises: S100, laying a geomembrane on a construction surface; S200, performing a test welding on the laid geomembrane; S300, detecting a result of the test welding; S400, when the result of the test welding does not satisfy set requirements, adjusting welding parameters again, and repeating step S200; and S500, when the result of the test welding satisfies the set requirements, performing a welding operation on the geomembrane, so as to weld the geomembrane to the construction surface. The present invention solves the problems that, when a geomembrane is constructed by means of laying, welding and testing, the construction quality of the geomembrane cannot be guaranteed and the anti-seepage effect of the whole project is affected due to lack of perfect construction methods and test standards. The laid geomembrane is first subjected to test welding, then the result of the test welding is detected, and the geomembrane is subjected to welding when said result satisfies the set requirements, ensuring the welding quality of the geomembrane, improving the anti-seepage effect of the geomembrane.

Description

Construction method of geomembrane

Cross-reference of related applications

This application requires the priority of the Chinese patent application with the application number CN201811315940.4 and the name "Construction Method for Geomembrane" submitted to the China Patent Office on November 06, 2018, the entire contents of which are incorporated by reference in this application.

Technical field

This application relates to the technical field of construction methods of anti-seepage materials, in particular to a construction method of geomembrane.

Background technique

As a commonly used anti-seepage material, geomembrane is mainly used as an anti-seepage structure in the landfill project. Therefore, the construction quality of the geomembrane will affect the anti-seepage effect of the entire project.

In the above prior art, the construction of the geomembrane includes the following steps: laying, welding, and acceptance procedures. Due to the lack of perfect geomembrane construction methods and inspection standards, the construction quality of the geomembrane cannot be guaranteed, and the anti-seepage construction The quality problems frequently occurred, which seriously affected the anti-seepage effect of the overall project.

Summary of the invention

The purpose of this application is to provide a construction method of geomembrane to solve the following technical problems in the prior art: due to the lack of perfect geomembrane construction methods and inspection standards, the construction quality of geomembrane cannot be guaranteed, thereby affecting the overall The anti-seepage effect of the project.

A construction method of geomembrane provided by this application includes:

S100, laying the geomembrane on the construction surface;

S200, test welding the laid geomembrane;

S300, check the test welding results;

S400, when the test welding result does not meet the set requirements, re-adjust the welding parameters, and repeat step S200;

S500. When the test welding result meets the set requirements, perform a welding operation on the geomembrane to achieve the welding of the geomembrane on the construction surface.

Further, the step S200 includes:

S201, setting welding equipment parameters;

S202, take the geomembrane sample for test welding;

S203, the shear strength and peel strength test of the welded seam are performed on the geomembrane sample after the test welding;

S204, when the test values of shear strength and peel strength are lower than the specified values, debug the welding equipment parameters, and repeat step S202;

S205, when the test values of the shear strength and the peel strength are higher than the prescribed values, welding operation is performed on the geomembrane.

Further, in the step S202, the environmental welding temperature α of the geomembrane sample has a value range of 5 ° C <α <40 ° C.

Further, in the step S203, when the shear strength and peel strength test of the welded seam are performed on the geomembrane sample after the test welding, it is checked whether the geomembrane sample is torn.

Further, in the step S500, a double-seam hot-melt welding is adopted at the strip connection between two adjacent geomembranes;

The steps of the double-seam hot melt welding include:

S501, preheating of welding equipment;

S502, check whether the value range of the lap width of the geomembrane is between 100mm ± 20mm, and then insert the geomembrane into the welding equipment;

S503, welding the geomembrane using welding equipment.

Further, in the step S500, a single-seam extrusion welding is used at the intersection of the connections between the multiple pieces of geomembrane;

The steps of single-slot extrusion welding include:

S504, determine whether the value range of the lap width at the weld of the geomembrane is between 75mm ± 20mm;

S505, bonding the overlapping parts of the geomembrane, the distance between the bonding points ranges from 60mm to 80mm;

S506, the surface of the geomembrane weld at a width of 30 mm to 40 mm is subjected to roughening treatment, and it is checked whether the depth of roughening is less than 10% of the film thickness.

Further, in the step S505, the value of the thickness of the center of the weld is 2.5 times the value of the thickness of the film, and the value of the thickness of the center of the weld is between 3 mm and 5 mm.

Further, in the step S505,

When a joint cannot be continuously welded, the welded seam needs to be roughened to check whether the length of the roughened is greater than 50mm, and when it is detected that the length of the roughened is greater than 50mm, lap welding is performed.

Further, before the step S100, it also includes a grassroots inspection step;

In the base layer inspection step, it is checked whether the surface depth of the construction surface is within a distance of 25 mm to 30 mm for the presence of debris that damages the geomembrane.

Further, after the step S500, it also includes non-destructive testing and destructive testing of the weld seam:

When the test data is qualified, enter the next process;

When the test data fails, rework or repair the weld.

This application provides a construction method of geomembrane, first laying the geomembrane on the construction surface to limit the location of the geomembrane; conducting a test welding operation on the paved geomembrane and testing the local geomembrane samples Welding, in order to detect the test welding results; and then test the results of the test welding, when the test welding results do not meet the set requirements, indicating that the test welding results of the geomembrane sample can not meet the requirements, you need to re-adjust the welding parameters, in order to Timely feedback of test welding results; when the test welding results meet the set requirements, it indicates that the test welding results of the geomembrane samples can meet the requirements, and the welding operation can be performed directly on the geomembrane, so that the geomembrane is accurately welded on the construction surface , Completed the welding process of geomembrane. The construction method of the geomembrane of the present application has rigorous procedures and simple operation, which can effectively guarantee the construction quality, reduce material consumption, and eliminate the leakage of geomembrane caused by construction.

BRIEF DESCRIPTION

In order to more clearly explain the specific embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings required for the specific embodiments or the description of the prior art. Obviously, the appended The drawings are some embodiments of the present application. For those of ordinary skill in the art, without paying any creative labor, other drawings can also be obtained based on these drawings.

FIG. 1 is a flowchart of a construction method of a geomembrane provided by an embodiment of this application.

detailed description

The technical solutions of the present application will be described clearly and completely below with reference to the drawings. Obviously, the described embodiments are part of the embodiments of the present application, but not all of them. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

In the description of this application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings, only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, with a specific orientation The construction and operation cannot therefore be understood as a limitation of this application. In addition, the terms "first", "second", and "third" are for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection", and "connection" should be understood in a broad sense, for example, it can be fixed connection or detachable Connected, or connected integrally; either mechanically or electrically; directly connected, or indirectly connected through an intermediary, or internally connected between two components. For those of ordinary skill in the art, the specific meaning of the above terms in this application can be understood in specific situations.

As shown in FIG. 1, the geomembrane of the present application is polyvinyl chloride geomembrane, polyethylene geomembrane, ethylene / vinyl acetate copolymer geomembrane, ethylene vinyl acetate modified asphalt blend geomembrane, linear low density polyethylene geomembrane Any of them.

The construction method for geomembrane provided by this application includes the following steps in this order: grass-roots inspection, field measurement, laying, test welding, test welding result detection, welding, and inspection acceptance.

Further, before step S100, a grassroots inspection step is required;

In the grassroots inspection step, the construction surface should be inspected before the construction of the geomembrane, whether the surface of the construction surface is smooth and uneven, and whether the surface depth of the construction surface is within a distance of 25mm to 30mm There are debris that damage the geomembrane, these debris include hard debris, spiked particles and harmful debris.

After the basic level inspection step, the construction surface needs to be measured on the spot to determine the working surface of the site construction, and the laying area of the geomembrane should be rationally planned to avoid the measurement of the size during construction. Too many geomembrane materials are laid, resulting in material loss.

S100, laying the geomembrane on the construction surface;

During the laying of the geomembrane, check the surface of the geomembrane for the presence of oil stains, fuel or splashed chemicals that damage the geomembrane to ensure that the surface of the geomembrane is dry and clean.

And check whether there are flammable and explosive substances in the area where the geomembrane is laid. These flammable and explosive substances include: matches, lighters, chemical solvents, etc.

Check the surface of the geomembrane for folds and creases to ensure that the surface of the geomembrane is flat.

During the storage and transportation of geomembrane, when the ambient temperature is relatively high, the geomembrane coil will cause adhesion. When laying the geomembrane, check whether there is adhesion on the surface of the geomembrane to ensure that the surface of the geomembrane is smooth. No sticking.

In addition, only the equipment and tools in use can be placed on the surface of the geomembrane, and other equipment and tools should not be placed on the surface of the geomembrane to avoid damage to the surface of the geomembrane.

When the position of the laid geomembrane is readjusted, it is necessary to check whether the surface of the geomembrane is damaged at any time.

S200, test welding the laid geomembrane;

S300, check the test welding results;

Further, the step S200 includes:

S201, setting welding equipment parameters;

Before the trial welding of the geomembrane, the welding temperature, welding speed and other parameters of the welder are set according to experience to make it in the best working state to ensure the quality of the weld of the geomembrane.

S202, take the geomembrane sample for test welding;

The width * length of the geomembrane sample is 300mm * 600mm.

If the ambient temperature is higher than 40 ℃ or the ambient temperature is lower than 5 ℃, it is not conducive to the welding of the weld and affects the quality of the welding. Therefore, the ambient temperature during welding must be strictly controlled.

Place the geomembrane sample on the electric tensile tester, or place the geomembrane sample on the manual tensile tester to test the shear strength and peel strength of the welded seam of the geomembrane sample after test welding.

The inspection standards of shear strength and peel strength are shown in Table 1.0 below:

Table 1.0 Standards for judging the strength of hot melt and extrusion welds

The above test conditions are: the temperature of the welding environment is 25 ° C, and the welding speed of the welding machine is 50 mm / min.

When testing the shear strength and peel strength of the geomembrane sample after the test welding, the geomembrane sample can only be torn and no damage to the weld joint can occur. Once the weld joint is damaged, a detailed record should be made.

During the shear strength test, when the test value is lower than the above-mentioned value of the shear strength, the welding temperature, welding speed and other parameters of the welding machine are readjusted, and then step S202 is repeated until the test value is higher than the above-mentioned shear strength value.

During the peel strength test, when the test value is lower than the above value of the peel strength, the welding temperature, welding speed and other parameters of the welding machine are re-adjusted, and then step S202 is repeated until the test value is higher than the above peel strength value.

In addition, when the temperature and wind speed of the external environment change significantly, the welding temperature and welding speed of the welding machine should be adjusted in time to ensure that the weld quality can meet the specified requirements.

During the shear strength test, when the test value is higher than the above value of the shear strength, the welding temperature, welding speed and other parameters of the welding machine are locked.

During the peel strength test, when the test value is higher than the above value of the peel strength, the welding temperature, welding speed and other parameters of the welding machine are locked.

When the shear strength test value and the peel strength test value of the geomembrane have reached the above specified standards, the welding operation of the geomembrane is started based on the above data, and step S500 is executed.

When all the data measured in the above step S205 can reach the set standard value, the welding operation is started.

In the step S500, the strip connection between two adjacent geomembranes, that is, the welding area of a larger area is double-seam hot-melt welding; at the intersection of the connections of multiple geomembranes, that is At the welding area of smaller area, single-squeeze extrusion welding is adopted.

Whether before double-seam hot-melt welding or single-seam extrusion welding, test welding of geomembrane is required.

Whether after double-seam hot-melt welding or single-seam extrusion welding, it is necessary to perform quality inspection on the weld after completion of welding.

In the process of laying the geomembrane, if it is found that the geomembrane is damaged, or the welding defect is found during the welding process, or the unqualified part of the geomembrane is found during inspection, it should be repaired in time.

Further, in the step S500, a double-seam hot-melt welding method is adopted for the strip connection between two adjacent geomembranes;

The steps of the double-seam hot melt welding include:

S501, preheating of welding equipment;

After the welding machine is turned on, carefully observe the temperature rise displayed by the indicator to fully preheat the welding machine.

S502, check whether the value range of the lap width of the geomembrane is between 100mm ± 20mm. Before welding the geomembrane, clean the membrane surface within the lap width of 200mm, and wipe off the dust on the membrane surface with a wet rag. Dirt, keep the membrane surface clean and dry;

Check the welding position of the geomembrane for scratches, stains, moisture, dust and other impurities that hinder and affect the construction quality.

Then insert the geomembrane into the welding machine, the overlapping position of the adjacent geomembrane is accurate, and the overlapping speed is rapid;

S503, welding the geomembrane with welding equipment;

During the welding process, the welding staff pays close attention to the condition of the weld and adjusts the welding speed of the welder at any time according to the quality of the weld to ensure the quality of the weld;

Welding personnel should also pay attention to keeping the weld seam straight and tidy, and adopt countermeasures for the uneven part under the membrane as early as possible to avoid affecting the welding operation of the welding machine.

During the welding process, once encountering a special fault, it should be stopped in time to avoid scalding the membrane surface.

When welding on a slope with a slope greater than 1: 3, the welding and auxiliary personnel must operate on the ladder and fasten the safety belt.

During the welding process, the value range of the power supply voltage of the welding machine is within 220V ± 11V. Once the value range of the power supply voltage is not within the above range, the machine should be shut down for maintenance work in time to ensure the safety of the welding machine.

Further, in the step S500, a single-seam extrusion welding method is used at the intersection of the connections between the multiple pieces of geomembrane;

The steps of single-slot extrusion welding include:

S504, before welding the geomembrane, first check whether the base layer at the seam is smooth and firm. If any foreign objects are found, it needs to be treated first, and then determine whether the value of the lap width of the geomembrane weld seam is within 75mm ± 20mm Between, the membrane surface at the seam is kept flat and the elasticity is moderate, without forming a fish-like wrinkle;

S505, the hot air gun is used to bond the overlapping parts of the geomembrane, and the interval of the bonding points ranges from 60mm to 80mm. During the bonding process, the temperature of the hot air needs to be controlled to avoid scalding the geomembrane , So that the geomembrane will not tear easily;

S506, the surface of the geomembrane weld at the width of 30mm to 40mm is treated with a sanding machine to make it thoroughly cleaned, forming a rough surface, and increasing the contact area; when sanding, it should be operated gently, less Damage the membrane surface, and finally, check whether the depth of roughening is less than 10% of the membrane thickness.

Further, in the step S505, when welding, the head of the welding machine is aligned with the seam, and no phenomenon such as sliding welding or jump welding can occur;

The value of the thickness of the center of the weld is 2.5 times the value of the thickness of the film, and the thickness of the center of the weld is in the range of 3 mm to 5 mm to ensure the firmness of the welding position.

Further, in the step S505,

When a joint cannot be welded continuously, the welded seam should be deburred to check whether the length of deburring is greater than 50mm. When the length of deburring is greater than 50mm, lap welding is performed to ensure the quality of the welding position.

In addition, in the above single-seam extrusion welding step, the electrode used should be kept clean and dry before being inserted into the welding machine. It is not allowed to use oily or dirty gloves, rags, cotton yarn, etc. to wipe the electrode.

In the process of single-seam extrusion welding, the weld seam is cooled in time according to the ambient temperature.

When the single-slot extrusion welding operation is interrupted for some reason, the extrusion amount of the electrode should be slowly reduced, and the welding must not be interrupted suddenly. When re-construction, the welding should be carried out from the interruption and then welded.

The work of the working group is centered on the welding staff and closely cooperates.

The deburring process is prior to welding, but it should not be exceeded. The extruded solder must be cooled in time, and the electrode delivery should be adapted to the welding speed.

When the test data is qualified, enter the next process;

When the test data fails, rework or repair the weld.

Non-destructive testing refers to the use of electric spark detectors and air pressure detectors to detect whether there are leaks in the weld.

The detection method of the electric spark detector is to use the characteristics of the geomembrane as an electrical insulator. When the instrument scans to the part with holes and the ground, or the part with pores and the ground, a bright electric spark is generated.

Before the single-slot extrusion welding construction, the diameter range is embedded in advance

Between the thin copper wires, so that after the welding is completed, the thin copper wires are connected to the power supply and scanned with a 35kV high-voltage pulse power probe at a height of about 10mm to 30mm from the weld; It means that the quality of the weld is qualified. When there is a spark, it means that the weld is not tight at this part, and it needs to be reworked and rectified before re-testing.

The detection method of the air pressure detector is to seal the two ends of the weld seam of the geomembrane to be detected, connect the air pressure tester, insert the needle into one end of the cavity, and pressurize the weld air cavity to 250kPa with the air pressure tester. Maintain for 3 to 5 minutes, the air pressure should not be lower than 240kPa, and then deflate the hole at the other end of the weld, the pointer of the air pressure gauge of the air pressure tester can quickly return to zero, indicating that the test is qualified.

Destructive testing refers to cutting a piece of geomembrane after welding and testing the strength of the sheared geomembrane with an electric tensile tester.

The detection method is the same as the detection method of the above-mentioned geomembrane sample test welding.

In the embodiment of the present application, first of all, check the laying of the geomembrane to meet the requirements of laying the geomembrane, measure the site on the spot, confirm the construction site on the site, and plan the construction area reasonably, and lay the geomembrane according to the plan; Before welding, take a 300mm × 600mm geomembrane sample for test welding. After the test welding is completed, the shear strength and peel strength of the weld are tested on an electric tensile tester. If the shear strength and peel strength are not satisfied The specified value will re-determine the parameters of the welding machine until the weld test value can reach the specified value. If the detected shear strength and peel strength meet the specified values, the parameters of the welding machine will be locked. At the same time, the test welding result Record; large-area geomembrane adopts double-seam hot-melt welding. The lap width of the geomembrane is 100mm ± 20mm. Before welding, the membrane surface in the range of about 200mm should be cleaned with a wet rag Wipe off dust and dirt to keep this part clean and dry. There should be no scratches, stains, moisture, dust and others on the welding site of the geomembrane Impediments that impede welding and affect construction quality; small-area geomembrane is welded by single seam extrusion. The overlap width of the geomembrane weld is 75mm ± 20mm. The membrane surface of the joint should be flat and moderately tight, so as not to form a fish mouth The folds of the geomembrane are bonded by a hot air gun. The spacing of the bonding points is between 60mm and 80mm. The temperature of the hot air is controlled. The geomembrane should not be scalded. The geomembrane cannot be easily torn apart. The geomembrane is welded. The film surface within the width of 30mm ~ 40mm at the seam is smoothed with a sanding machine to make it thoroughly cleaned to form a rough surface and increase its contact area, but its depth should not exceed 10% of the film thickness. Minimize the damage to the membrane surface; after the completion of the geomembrane welding, perform non-destructive inspection and destructive inspection on the weld seam, and rework or repair the unqualified weld seam. After the inspection is qualified, enter the next process, at the same time, draw the geomembrane laying Detailed drawing and welding result record table.

The construction method of the geomembrane provided in this application, after the grassroots inspection, also carried out on-site measurement of the laying site, construction planning, and reasonable laying of geomembrane lap, effectively reducing the loss of geomembrane materials.

Before welding, geomembrane adjusts the optimal parameters of the equipment by trial welding, so that the welding equipment is in the best working state, avoiding the weld quality problems caused by the poor equipment status during the welding process, and improving the construction quality of the weld. .

During the welding process, all the welds are inspected and accepted, and the unqualified welds are reworked or repaired until the inspection and acceptance are passed before the next process can be carried out to further ensure the quality of the welds and draw the geotechnical Membrane laying details, record the detection results of each weld, which is convenient for accurate positioning and rapid elimination of quality problems, and further improves the quality assurance system for geomembrane construction.

This application can be applied not only to the construction of geomembrane in landfills, but also to the construction of geomembrane in various anti-seepage pits, such as ditches.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: The technical solutions described in the foregoing embodiments can still be modified, or some or all of the technical features can be equivalently replaced; and these modifications or replacements do not deviate from the essence of the corresponding technical solutions of the technical solutions of the embodiments of the present application range.

Claims

A construction method of geomembrane is characterized by including:

S100, laying the geomembrane on the construction surface;

S200, test welding the laid geomembrane;

S300, check the test welding results;

S400, when the test welding result does not meet the set requirements, re-adjust the welding parameters, and repeat step S200;

S500. When the test welding result meets the set requirements, perform a welding operation on the geomembrane to achieve the welding of the geomembrane on the construction surface.
The construction method of a geomembrane according to claim 1, wherein in step S200, it comprises:

S201, setting welding equipment parameters;

S202, take the geomembrane sample for test welding;

S203, the shear strength and peel strength test of the welded seam are performed on the geomembrane sample after the test welding;

S204, when the test values of shear strength and peel strength are lower than the specified values, debug the welding equipment parameters, and repeat step S202;

S205, when the test values of the shear strength and the peel strength are higher than the prescribed values, welding operation is performed on the geomembrane.
The construction method of a geomembrane according to claim 2, wherein in step S202, the environmental welding temperature α of the geomembrane sample has a value range of 5 ° C <α <40 ° C.
The method for constructing a geomembrane according to claim 3, characterized in that, in step S203, when the shear strength and peel strength test of the welded geomembrane sample are tested, whether the geomembrane sample is torn is checked Bad.
The construction method of the geomembrane according to claim 4, characterized in that, in step S500, a double-seam hot-melt welding is adopted at the strip connection between two adjacent geomembranes;

The steps of the double-seam hot melt welding include:

S501, preheating of welding equipment;

S502, check whether the value range of the lap width of the geomembrane is between 100mm ± 20mm, and then insert the geomembrane into the welding equipment;

S503, welding the geomembrane using welding equipment.
The method for constructing a geomembrane according to claim 5, characterized in that, in the step S500, a single-seam extrusion welding is used at the intersection of the connections between the multiple pieces of geomembrane;

The steps of single-slot extrusion welding include:

S504, determine whether the value range of the lap width at the weld of the geomembrane is between 75mm ± 20mm;

S505, bonding the overlapping parts of the geomembrane, the distance between the bonding points ranges from 60mm to 80mm;

S506, the surface of the geomembrane weld at a width of 30 mm to 40 mm is subjected to roughening treatment, and it is checked whether the depth of roughening is less than 10% of the film thickness.
The method for constructing a geomembrane according to claim 6, characterized in that, in step S505, the thickness value of the center of the weld is 2.5 times the value of the thickness of the film, and the thickness of the center of the weld is in the range of 3mm to 5mm between.
The construction method of the geomembrane according to claim 7, wherein in step S505,

When a joint cannot be welded continuously, the welded seam needs to be roughened to check whether the length of the roughened is greater than 50mm, and when the length of the roughened is detected greater than 50mm, lap welding is performed.
The construction method of the geomembrane according to claim 1, characterized in that, before step S100, it further includes a grassroots inspection step;

In the base layer inspection step, it is checked whether the surface depth of the construction surface is within a distance of 25 mm to 30 mm for the presence of debris that damages the geomembrane.
The construction method of the geomembrane according to claim 1, characterized in that after step S500, it further includes non-destructive detection and destructive detection of the weld seam:

When the test data is qualified, enter the next process;

When the test data fails, rework or repair the weld.