Design And Micro Properties Of Damping-enhanced Gradient Structure Concrete

The damping function of concrete materials is of great significance to increase the safety and stability of high-speed train operation and the comfort of ride,improve the safety of large-span building structures and anti-vibration and noise reduction function.The damping function of concrete materials has also become a research Hot spots.At present,there are many studies on the damping function of concrete materials,also made some progress,but did not solve the technical problems of the damping function and mechanical properties can not have both.In order to solve the above problems,this paper introduces the theory of functionally graded material,integrates the material design and structural design of concrete,and develops Damping-enhanced Gradient Structure Concrete(DGSC).In order to improve the damping of concrete performance to open a new research ideas.Functionally graded concrete is usually composed of two or more kinds of materials.The DGSC of this research is composed of high damping concrete and high performance concrete,which constitute the damping layer and structural layer of concrete material respectively.The free damping structure form,through its material and structure to optimize the treatment,it has a high damping and high-intensity function.Through the research of the damping properties and mechanical properties of the DGSC,damping properties is improved by 30% and the compressive strength is over 50 MPa,and the damping and mechanical properties of DGSC are all at high level,Basically solved the contradiction between damping and mechanical properties,but also avoids the problem of high cost,is of important guiding value for the research of high damping concrete.The microhardness of interface transition zone(ITZ)between cement paste and aggregate of the high-damping concrete and high-performance concrete was measured by microhardness tester.The microhardness of the bond transition zone of DGSC was measured by microhardness tester too.The results show that the microhardness of interface transition zone of high damping concrete is more uniform and the the property of interface transition zone is improved.The microhardness of the interfacial bond zone of DGSC is improved obviously,which is higher than that of the high damping concrete.It has great significance to improve overall properties of DGSC.The microstructure of cement paste and aggregate interface transition zone(ITZ)of high damping concrete and high performance concrete,the interface bond zone of DGSC were studied by environmental scanning electron microscopy(ESEM).The results show that the interface transition zone of high damping concrete is uniform,the cement paste and the aggregate are compact and,and the damping reinforcement component is evenly dispersed in the slurry,which is beneficial to improve the high damping concrete damping function and mechanical properties.Then,the microstructures of the interface bond zone of DGSC are observed.It is found that the high damping materials in the interface junction area and the high-performance materials have mutual penetration,the interface bond zone is strengthened,and the damping properties and mechanical properties of the DGSC get promoted.In summary,through the integration of materials and structure design and development of the damping-enhanced gradient structure concrete to achieve a high damping high-strength function,the basic solution to the concrete damping performance and mechanical properties of contradictory technical problems,the development of DGSC will provide a broad prospect for the research and development of high damping and high strength concrete materials.