Development status of high performance geotextile
With the rapid development of China's society, the relationship between infrastructure construction and our country's economic development, people's livelihood and ecological protection has become more and more close.High-speed railway engineering, waste or sewage treatment related seepage engineering, mining and ecological bag slope protection engineering and other fields are constantly putting forward higher requirements and more needs for geosynthetic materials.Textiles that are generally used at the same time with foundations, soil, rock, soil or any other civil material and are an integral part of man-made works, structures or systems are geotextiles.High-performance geotextiles often have excellent mechanical properties, light resistance, temperature resistance, aging resistance and other characteristics, and can better play a role in strengthening, protection, isolation, water conduction, seepage prevention and other functions in geotechnical construction projects.In 1926, the Netherlands first applied geotextiles in the field of geotechnical engineering, in recent years, with the development and innovation of high-performance geotextile materials, will further promote the development of geo-building materials manufacturing technology and improve the level of construction and engineering construction.
1. Overview of high performance geotextiles
1.1Category
According to the different preparation methods, geotextile can be divided into woven geotextile, nonwoven geotextile and composite geotextile three categories.Woven geotextiles can be roughly divided into three types of products produced by weaving, weaving and knitting processes.Nonwoven geotextile refers to the oriented or random orientation of fibers, filaments, strips, etc., through spunbond, acupuncture or hot melt bonding method products.Nonwoven geotextile has high production efficiency, good extensibility, mechanical properties and horizontal permeation and filtration performance.Composite geotextile has more advantages than the first two types of geotextile, it is composed of two or more kinds of geotextile or geotextile related products, which has better comprehensive performance, is a kind of high-performance geotextile widely used in all kinds of engineering.
1.2 Raw Materials
The choice of geotextile raw materials must match the actual needs of the project, both considering the performance requirements of the geotextile site, but also considering the cost of the product.At present, the main raw materials of geotextile production are synthetic fibers.Synthetic fibers have the advantages of high strength and corrosion resistance, and at this stage almost all geotextiles will use synthetic fibers, including polyester (PET), polyethylene (PE), polypropylene (PP), polyamide (PA), polyvinyl alcohol (PVA) and so on.The production of high-performance geotextiles usually also needs to add additives to improve the performance of geotextiles, such as antioxidants, light stabilizers, ultraviolet absorption stabilizers, long-term heat stabilizers, processing modifiers, flame retardants, lubricants, antibacterial agents, etc.
1.3 Production Technology
The production technology of long silk spinning adhesive has the advantages of short production process, high production efficiency and high product performance.PP long-filament bonded needled geotextile is one of the main products of long-filament bonded needled nonwoven geotextile. It has the advantages of high modulus, high elongation, tear resistance, puncture resistance, acid and alkali resistance, low temperature resistance, mold resistance and low cost, especially in the underground acid, alkali, high cold and other harsh environments.At present, the woven geotextile products on the market mainly include flat silk woven geotextile, filament woven geotextile and so on.In addition, the production and application of composite geotextiles started relatively late compared with other types of geotextiles, but it is the focus of the development of geotextile production technology.
To be continued.
