The Experimental Research Of Piezoelectricity Of Carbon Fibers Concrete Under Low Temperatures

As one of building material, concrete has a history more than 100 years, Cement-based materials is the largest amount of man-made building materials. As an important structure material, strength is a central capability of concrete, high-strength is the direction of research and development in recent years. But the inherent weaknesses-poor capability of tensile strength, bending strength, impact toughness, has been limited the development of concrete's advantage, and, with the increase of strength, the weakness became more and more seriously. With the continuous development of modern technology of civil engineering, human request higher and higher about long-term safety testing and monitoring of major projects. So, the research about long-term safety testing and monitoring of major projects is an important scientific and technical issues. Gansu province is located in the north-west cold regions of china, the cold winter last for a long time, the concrete of bridges and roads cracks easily, the rapid extension of the cracks made the use of quality and time bridges and roads affected greatly. For these reasons, this article made the experiment research of carbon fibers concrete under low temperature, its mechanical performance, alert and resourceful characteristic were analyzed, for the purpose of the bases of theory and test for structural health monitoring.The central content of this article include:1) The experiment research of mechanical performance of carbon fibers concrete under low temperatureReviewed the situation of research of carbon fibers concrete home and abroad, brought forward the framework of research. Studied the properties of carbon fibers after 0,30,60,90 freezing and thawing cycles and got its discipline, which is the losing ratio of quality, the losing ratio of compression strength and tensile strength, the change of Young's modulus, the change of impact toughness.2) Study of the piezoelectricity of carbon fiber concrete memberTook the test on the carbon fiber concrete specimen about electromechanical effect, got the discipline of compression and electrical resistivity, and analyzed its reason. At the same time, study the stress, strain and electrical resistivity in the compression region of carbon fiber concrete beam, got the interaction of curvature. Investigated the failure law of carbon fiber-steel mesh reinforced concrete sheet, and confirmed steel mesh could strengthen the bending strength, but the steel mesh only one tier.