The End Effect Of Carbon Fiber Plate Clamped By The Waveform Anchorage And The Finite Element Analysis

In the technologies of structure’s strengthening and reinforcement, the technology with pre-stressed CFRP plate combinates all the advantages of pre-stressed reinforcement techology and CFRP plate. As an active reinforcement technology, since it can make the most of the high tensile strength of CFRP materials, the yield load and the ultimate bearing capacity of structure can be significantly improved. Compared with ordinary bonding reinforcement, Pre-stressing CFRP technology can effectively solve the problem of stripping damage; thus there is broad space for its development and good prospects of its application. As a kind of newmaterial, CFRP plate is very different form the traditional pre-stressed steel on the material properties and the shape, so we should rerecognize its tensile properties and its connecton performances with anchorage.However, due to the low extrusion stiffness of CFRP plates they are easilybroken by an anchor, which leaves that the core problem of Pre-stressing CFRPtechnology is the design of anchorage. The fundamental requirement of the anchorage is: for a guaranteed safe anchoring, an anchorage with a tonnage big enough is demanded based on the material and shape characteristics of CFRP plate;make sure that the CFRP plate is evenly tensed, and reduce the End Effect asmuch as possible in order to maximize the high tensile strength of CFRP plate.“High-strength polymer materials wave-form anchorage”(patent no.ZL02244587) is specially designed to anchor the FRP sheet materials. The paper through theoretical analysis and experimental research proves that: compared with the sleeve anchorage, waveform-anchorage can avoid the shear failure of CFRP plate; compared with the plain anchorage, waveform-anchorage can avoid the sliding failure ofCFRP plate.In this paper, we refer to the End Effect which contains the Poisson effectand the Vertical Compression Effect. Theoretical analysis and finite element analysis of Poisson Effect have been carried out respectively and the following conclusion has been made in this research: transverse constraint of the anchorage to the CFRP plate can aggravate the stress concentration effect of the CFRP plate atthe front exit of the anchorage; if we can release the transverse constraints, andchange the internal transverse friction shear stress stress nephogram of the anchor age, we can significantly reduce the Poisson Effect. The Vertical Compression Effect is also analyzed in detail in this paper, a conclusion can be drawn: waveform-anchorage can significantly alleviate the Vertical Compression Effect. The experimental study on the End Effect is also analyzed in detail in this paper, a conclusion can be drawn: its results are consistent with the finite element analusis; the proportion of the Vertical Compression Effect is very small in the End Effect.