Which material should be chosen for reservoir geomembrane?
It is very important to choose the material of the reservoir geomembrane because it directly affects the sealing and durability of the reservoir. The following are some commonly used reservoir geomembrane materials and their characteristics:
High Density Polyethylene (HDPE):
Advantages: HDPE geomembrane generally has high chemical stability and mechanical strength, and can provide excellent chemical resistance and water barrier properties. They are also relatively resistant to aging.
Applicable scenarios: HDPE membrane is suitable for various reservoir projects, including water storage, anti-seepage, anti-pollution and environmental protection.
Linear low density polyethylene (LLDPE):
Advantages: LLDPE geomembrane has good ductility and tear resistance, and is suitable for flexible substrate surfaces. They also have good chemical resistance.
Applicable scenarios: LLDPE membranes are often used in applications that require a certain degree of ductility, such as reservoirs in areas with uneven terrain or need to adapt to earthquakes.
Polyvinyl chloride (PVC):
Advantages: PVC geomembrane has high chemical stability and UV resistance, and is suitable for outdoor exposure environments.
Applicable scenarios: PVC membrane is suitable for some reservoir projects that require long-term exposure to ultraviolet rays and extreme climate conditions.
Advantages: Composite geomembranes are usually composed of a laminated combination of two or more different materials, making full use of the advantages of various materials to provide higher performance.
Applicable scenarios: Composite geomembrane is suitable for reservoir projects that require higher strength, better anti-seepage performance or special environments.
Advantages: Rubber geomembrane usually has excellent elasticity and aging resistance, and is suitable for reservoir projects with special requirements, such as high bending, high temperature or chemically corrosive situations.
Applicable scenarios: Rubber membranes are suitable for reservoir projects with special environments and requirements.
When selecting reservoir geomembrane materials, the following factors need to be considered:
Chemistry of soil and reservoir environments, including pH and concentration of chemicals.
The climate and temperature range of the reservoir area.
The topography and topography of the land, including whether it needs to accommodate the risk of earthquakes or other natural disasters.
Generally, you should work with a professional engineer or geomembrane manufacturer to ensure that you select a material that is appropriate for your specific reservoir engineering needs and that relevant engineering codes and standards are followed.
How to install reservoir geomembrane
The correct installation of reservoir geomembrane is crucial because it directly affects the sealing and anti-seepage performance of the reservoir. The following are the general installation steps for reservoir geomembranes:
Before starting the installation, the surfaces of the reservoir bottom and side walls need to be cleaned and prepared. Make sure the surface is flat, dry and free of sharp objects and rust.
Laying the base film:
When laying the base membrane, first unroll the geomembrane roll to ensure sufficient overlap to prevent leakage. Generally, the overlap should be at least 1-2 feet (30-60 cm).
Use anchors or other methods to secure the bottom membrane to the bottom surface to prevent it from moving as the reservoir fills.
Welded or bonded seams:
If multiple rolls of geomembrane are used, the seams will need to be welded or bonded to ensure a tight seal. This usually requires specialized hot melt welding equipment or suitable adhesives.
Install side wall membrane:
If you need to install a geomembrane on the side wall of a reservoir, you also need to ensure that the surface is clean and flat.
Lay the side wall membrane vertically along the side wall of the reservoir to ensure that the joint with the bottom membrane is firm.
Connect the sidewall and bottom membrane:
The connection between the bottom membrane and the sidewall membrane should be strong to ensure that water does not leak under the geomembrane.
Install auxiliary equipment:
Install necessary auxiliary equipment, such as anti-seepage walls, drainage systems and safety facilities, to ensure the normal operation and safety of the reservoir.
Check and test:
Before filling the reservoir with water, perform a careful inspection to ensure there is no damage, holes or problems with the geomembrane.
Permeability testing can be performed to ensure the tightness of the geomembrane.
Fill the reservoir:
Once you confirm that the geomembrane is installed correctly and there are no issues, you can begin filling the reservoir.
Monitoring and Maintenance:
Regularly monitor the condition of the reservoir geomembrane, especially after initial use and when water levels change significantly.
Maintain the reservoir and geomembrane regularly and promptly repair any damage or holes.
During the installation process of reservoir geomembrane, it is best to have it carried out by professional engineers or contractors to ensure compliance with relevant engineering standards and specifications, as well as to ensure the long-term performance and safety of the reservoir. In addition, local climate conditions and environmental factors need to be considered during the installation process to ensure the adaptability of the geomembrane.
What other geotechnical materials should be used with reservoir geomembrane?
In reservoir projects, reservoir geomembranes usually need to be used in conjunction with other geotechnical materials to ensure the stability, anti-seepage performance and durability of the project. Here are some common geotechnical materials used with reservoir geomembranes:
Geogrid: Geogrid is a mesh-structured material usually used to enhance the tensile strength of soil. It can be used under or above the reservoir geomembrane to help disperse loads, reduce soil settlement and increase friction between the geomembrane and soil.
Geotextile: Geotextile is a textile material commonly used to separate, filter and strengthen soil. In reservoir projects, it can be used to separate the reservoir geomembrane and foundation soil to prevent soil particles from penetrating and damaging the geomembrane.
Seepage Barrier: Seepage barrier is usually constructed of concrete or other materials with good sealing properties and is used to enhance the anti-seepage performance of reservoir projects. They can be used in conjunction with reservoir geomembranes to ensure the reservoir does not leak.
Drainage system: The drainage system includes drainage pipes, infiltration wells and infiltration trenches, etc., which are used to control the water level in and around the reservoir and remove accumulated water to reduce the impact of water pressure on the geomembrane.
Revetment structures: Revetment structures, such as concrete revetments or rock revetments, can be used to protect the geomembrane edge of a reservoir from erosion and physical damage.
Fill material: Fill material, such as crushed stone, gravel or sand, can be used to cover the surface of the reservoir geomembrane to protect it from UV rays, mechanical wear and environmental factors.
Filter layer material: The filter layer material is usually located under the geomembrane to filter seepage water and prevent fine particulate matter from entering the geomembrane and damaging its anti-seepage performance.
Fixing and connecting materials: Fixing and connecting materials, such as bolts, steel wires and welding materials, are used to connect geomembrane rolls, joints and other geotechnical materials to ensure their stability and sealing.
When designing and constructing reservoir projects, these geotechnical materials need to be selected and combined according to specific engineering requirements, geographical conditions and environmental factors to ensure the safety and performance of the reservoir. It is recommended that professional engineers and geologists be consulted during the engineering process to determine the most suitable combination of geotechnical materials.