| The rock anchor technology is being used in a wide range of ground or rock conditions. They can improve the strength and reliability of ground, reduce the dimension of structures and lighten their weight. So they can save the materials in engineering. With increased experience and improved anchoring techniques, steel anchors has become a common practice in almost every aspect of civil engineering such as slopes, foundations, mines, tunnels, underground excavations, concrete dams, airports, aerodrome, ports, retaining wall, bridge abutments, rehabilitation of existing concrete structures and so on.However, the traditional anchors which made of steel are easy to rust. When used as structural members in Underground or underwater engineering, they will pose serious challenges to the safety and durability of structural because of the difficult to change. Although the FRP bars have the good features of light weight, high strength, corrosion-resistant and non-conductive, the factors of lower elasticity modulus ,Small shear modulus, the long-term temperature resistance, aging less and high cost of production also confined they widely used in civil engineering. The FRP-steel anchor is a new type of anchor which used Overall wet forming GFRP on the outer surface of ordinary hot-rolled steel bolt. The shell has the function of waterproof, permanent rust and improves the durability of bolt. The FRP combined with steel can play a high modulus of elasticity of steel; it also can play the advantages of Anti-corrosion, anti-fatigue properties of FRP, to achieve complementary effects.This article is based on experiment, and done in-depth study on the material composition, corrosion, tensile properties, process of FRP-steel anchor, takes a real projection of slope as an example to testing the new bolt anchorage's performance. This study provides the necessary basic data and analytical tools for the Related Design and Construction Points of FRP-steel anchor, and get an Instructive for the widely used of FRP-steel anchor.This paper's main findings and conclusions are as follows:①Comprehensive compare various fiber's performance and prices, choose the E type of GFRP material as the Outsourcing steel bolt material, after soak with binder which made of epoxy phonetic resin and acetone solution, it has a good bonding properties with steel.②After immersed in a certain concentration of sulfuric acid, NaOH solution, Nacl solution and Current accelerated corrosion, testing the Mechanical Properties of FRP-steel anchor, and made a comparison with steel anchor which Under the same kinds of conditions .The result proved the FRP-steel anchors have good resistance to acid, alkali, salt and corrosion characteristics of current. ③summarized on the basis of home and abroad'study, used the Laminated plate theory to prove that the optimum angle for FRP to worry the steel is 45°,and get the Composite rod's theory of stress - strain curve. Tensile the bar which worried with different Fiber residue layers and inner core material, get the relationship of FRP-steel anchor's Mechanical properties which winding different layers and rods core materials.④confer the factors which effect bond strength of cementing material and FRP-steel anchor ,the method of Bolt anchorage force calculation ,Presented the characteristics of anchor bolts'design methods for the new structural.⑤Take the real projection of slope as an example to validate the performance of anchor, The results showed that the FRP-steel bars'actual anchoring effect similar as steel bars, but the Anti-corrosion effect superior than steel bars.
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