The Anchoring Mechanism And The Numerical Analysis Of The Fiber Reinforced Polymer Tendon

Steel anchors are 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 have 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.With the engineering applications, it has been shown that there exist some problems in steel anchors such as corrosion of steel tendon, requirements for corrosion protection, heavy weight, difficulty in transportation and installation. These disadvantages of steel restrict their applications to a certain extent. Above all, the corrosion of steel anchors not only affects the durability of steel anchors, but may result in serious accidents. Fiber reinforced plastic (FRP) rebar is a new composite material. It is composed of fiber filaments and a resin matrix. The fiber of high tensile strength and high modulus of elasticity is used as reinforcing material. The synthetic resin is used as matrix material and is mixed with adequate auxiliaries. The fiber reinforced plastic rebar is manufactured using a pul-trusion method and necessary surface process. It offers significant advantages over conventional reinforcing steel bars, namely, high tensile strength to weigh ratio, excellent chemical resistance, liable to design, high fatigue strength and electro-magnetic neutrality. So the fiber reinforced plastic bar anchors can make the anchoring techniques have a more wide range of rock engineering applications.However, few investigations and filed applications are available recently. In our country, theory analysis has just begun, no information is available for the field applications, and the design theories have already been formed. According to the available investigations at home and abroad, main problems should be attached importance to. namely, the study of the properties of FRP rebar and concrete/cement grout is scarcely investigated; The definite bond-slip theoretical differential functions have not been available, which takes into account the effect among FRP rebar members; the calculating method and the numerical analysis of applied tensile load about FRP anchor have not taken seriously, in according tothe three factors reminded in the front; and the properties of bond materials (such as cement grout) and rock, has not yet been attached importance to.In order to make the FRP rebar anchors widely applied in anchoring engineering, with the help of the Physical Science Fund of our country (the title of the item: Research into the anchoring mechanism of FRP anchors, No. 0079028) and The Prominent Youth Fund of Henan province, proceeding the theory analysis and numerical simulator. In the case of the three mutual effects of the anchor, the concrete anchorage and the rock, selecting the reasonable loading model, the bond-slip differential equation is derived. Based on the about the practical anchoring experiments in the concrete block (in the laboratory) and in the rock (in the field), the study of the mechanical properties of FRP tendon anchors is made. According these experimental parameters and the data, the simulators are made up and displayed in the computer. These researches provide the basis and the methods for the application of FRP anchors. The main achievements of this dissertation are as follows:1. The testing method of the behavior about the bond of FRP rebar to concrete, the bond mechanisms and influential factors are discussed. According to the mechanism of force transference between FRP rebar and concrete, this dissertation discusses the relationship among bond stress, the stress of FRP bar and embedment length. Based on the summary of the existence bond-slip relation models home and abroad, the continuous smooth...