Research On Toughness Of Crumb Rubber Concrete

Since the “12th Five-year Plan”, China has been made the Green-Development as the theme, and also put forward some related requirements to civil construction industry, that required greater efforts to develop new environment-friendly building materials and products. It was clearly stated in the green building evaluation criteria in 2006 that green building could protect the environment and conserve resources, and reduce environmental pollution as much as possible by maximum using recycled renewable materials during the entire service process of the building. Nowadays, the scrap tire rubber has resulted in seriously "black pollution", and the appearance of Crumb Rubber Concrete can make discarded rubber resources, which solves a lot of problems of environmental pollution of waste rubber, but also provides a new kind of environment-friendly green materials for the construction field.Since 1960, domestic and foreign scholars have done a lot of research work on Crumb Rubber Concrete and achieved numerous valuable results, including its working performance, mechanical properties, deformation properties, durability properties, fatigue resistance, sound insulation, heat insulation performance and the constitutive relation, etc. However, the existing research about the toughness of Crumb Rubber Concrete under uniaxial compression showed the changes of concrete toughness with different rubber content from the failure modes and the ratio of tension-compression, etc. Others qualitatively analyzed the influence of rubber content on concrete toughness without considering the decline of stress- strain curve. Moreover, the research on the toughness of Crumb Rubber Concrete under equal compressive strength is less. In this thesis, Crumb Rubber Concrete of cube compressive strength of 30 MPa and 40 MPa is determined as the starting point for study the influence of rubber particle volume fraction(0、10% and 15%) on the mechanical properties, toughness and deformation of crumb rubber concrete under equal compressive strength. The work analyses quantitatively the rubber particles content influence on concrete toughness first time. The study enriches the research of rubber particle concrete, and provides a basis for engineering practice.At first, this thesis introduces the research status of crumb rubber concrete at home and abroad, and then put forward a kind of device which is used for determining the stress-strain curve of crumb rubber concrete and analyses the applicability of the equipment by using the software ANSYS. According to the studies of this thesis, the raw materials, the test equipment, the mixture ratio and the methods are determined. Research shows that the method which evaluates the toughness of Crumb Rubber Concrete according to the whole stress-strain curve and with reference to American ASTM standard is feasible. We can use YNS-Y3000 electro-hydraulic servo pressure testing machine(with matching grating) to measure the compressive stress-strain curve of Crumb Rubber Concrete with the displacement control loading way. The calculation results of toughness show that concrete with rubber has obvious ductile failure characteristics under uniaxial pressure than concrete without rubber. Its toughness index is greatly improved,and concrete with more dosage of rubber particles,the better toughening effect within a certain range.