As a structural material, concrete is widely used in engineering construction, and concrete ponds are also widely used. In the process of using concrete (soil) pools, due to long-term exposure to sunlight, rain, water infiltration and other environments, plus the carbonization of concrete itself, problems such as cracking and strength reduction will occur, which may even cause concrete (soil) The pool collapsed. Various types of (sewage) pools in chemical projects also have a greater risk of pollution to surrounding groundwater, and the treatment of groundwater after pollution is difficult, long, and expensive. Surface FRP is made of resin, fiberglass cloth, curing agent, catalyst, and additives in a certain proportion. It has good strength and flexibility, low manufacturing cost, simple construction and easy maintenance. Therefore, in order to prevent the chemicals in the sewage from seeping into the ground and entering the surface water body, and at the same time to ensure the durability of the concrete's anti-seepage, it is particularly important to apply anti-corrosion paint to the reinforced concrete side walls and bottom of the pool and paste FRP cloth.
Selection and mixing ratio of raw materials: The main raw materials of epoxy resin fiberglass are epoxy resin curing agent, thinner and fiber reinforced materials, and the auxiliary raw materials are putty powder, quartz sand, talc powder and color paste. The focus of raw material control is on the main raw materials.
(1) Epoxy resin: The varieties of epoxy resin include EP01441-310 and EP01451-310 bisphenol A type. Commonly used for construction is EP01451-310 bisphenol A type, namely E44 brand (old brand is 6101), and its quality conforms to the relevant provisions of the current national standard "bisphenol A epoxy resin" (GB/T13657). The main performance control indicators include epoxy value, inorganic chlorine value, organic chlorine value, volatiles, softening point, viscosity. Before construction, you should check the factory quality certification documents and check the technical parameters. If necessary, you should witness the sampling and send it to a third-party qualified laboratory for re-inspection.
(2) Curing agent: The low-toxic curing agent is preferred, and the moisture curing epoxy curing agent is selected for the wet base. The main performance control indicators include curing time, viscosity, amine value, and appearance. The T31-B8 epoxy resin curing agent used in this project is a modified amine curing agent with low toxicity and rapid curing at room temperature. It needs to be stored in a dry and ventilated place.
(3) Thinner: Epoxy resin is diluted with reactive diluent and non-reactive diluent. This project uses benzyl alcohol diluent. The material itself is non-toxic or low-toxic, has a high boiling point, and is not volatile. After curing, because benzyl alcohol has strong polarity, it can be well compatible with epoxy resins and will not migrate; it can promote the reaction of epoxy resins with amines, accelerate the reaction speed, and has good hydrophobic properties ; Can significantly improve the gloss of the coating to prevent the appearance of whitening; can improve the toughness of the cured product.
(4) Fiber reinforced materials: for acid (except fluoric acid), alkali and salt media, non-paraffin emulsion type untwisted coarse glass fiber checkered plain cloth; for fluoric acid media, polyester and polypropylene And other organic fiber cloth. The thickness of the cloth is 0.2-0.4mm, and the density of warp and weft per square centimeter is not less than 4×4-8×8mm. The main performance control indicators include breaking strength in warp and weft direction, thickness and weight in warp and weft density.
(5) Other materials: blended powder, coarse and fine aggregate should be clean and dry. The main performance control indicators are acid resistance, water content, particle size and fineness