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Concrete is a leading civil engineering materials, in the north, winter construction of concrete structures often because freezing measures unfavorable, after pouring the concrete being inadvertently leaving insulation damage, especially in the new Civil durability of concrete structures in recent years has caused people to high priority. While in the old building, due to various reasons, there is a situation of low strength concrete, renovation and reinforcement works in the construction industry are also growing in importance. The last century, the rise of externally bonded FRP reinforcement materials, methods, FRP (Fiber ReinforcedPolymers) as a reinforcing material for lightweight, high strength, non-magnetic, good fatigue resistance and corrosion resistance and other significant advantages more and more used in civil engineering projects. With the extensive application of FRP, FRP reinforced concrete structure will be subject to a variety of environmental impact or low concrete strength. Research FRP reinforced concrete members overall durability of practical significance. Domestic and foreign scholars on FRP reinforced concrete structures and durability of the overall performance of a lot of experimental research, but mostly concentrated in the carbon fiber FRP (CFRP) and glass fiber (GFRP) and other FRP, while good for the price basalt fiber (BFRP ) Experimental study on reinforced concrete structures is rare. In this paper, freeze-thaw cycle test to study the freeze-thaw environment Konishi basalt fiber materials and resin (made in Japan) tensile strength, elastic modulus, elongation and other basic mechanical properties of basalt fiber and concrete bonding properties between the positive pull , as well as freeze-thaw environment basalt reinforcement under different intensity levels (C15, C20, C30) concrete beam flexural test study for the test more frequently occur during debonding pattern of cracks caused by cross-beams made composite materials and concrete interface BFRP separation between a computational model of ultimate bearing capacity. This major work done as follows: 1, the production of basalt fiber sheets 15 and 15 resin specimens, divided into three groups of five specimens, respectively, after freeze-thaw cycle 0 times, 50 times, 100 times, freeze-thaw study basalt fiber loop and a resin test piece basic mechanical properties (tensile strength, elastic modulus, elongation) of. 2, making 60 concrete cubes (100 × 100 × 100) specimens, research thaw 0 times, 25 times, 50 times, 75 times different strength grade concrete and basalt fiber interface is pulled bonding properties. 3, the production of 45 concrete beam specimens, specimens of each intensity level 15, to change the number of freeze-thaw cycles, the concrete strength at a different level, first with FRP reinforcement after thawing and freezing and thawing before changing parameters such as study freeze-thaw environment using different intensity levels basalt reinforcement of reinforced concrete beams cracking load, ultimate bearing capacity and failure mode analysis of basalt reinforcement of low strength concrete specimen viability. 4, reinforced concrete beams under BFRP several failure modes, were introduced three common methods for solving the ultimate bearing capacity. For this experiment appear more frequently in the form of debonding, put forward the corresponding capacity calculation model, and compared with experimental results, we can see stripping capacity calculation model is somewhat safe, conclusions provide a theoretical basis for engineering applications.
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