Damping capacity of materials and its effect on the dynamic behavior of structures. Review

Abstract Damping is very important when studying the vibrations of bridge structures. A distinction is made between structural damping and damping due to internal friction in the material. The damping ability of the material allows it to absorb energy for irreversible processes during its cyclic deformation. That is why, when designing bridge structures, special attention is paid to the damping properties of the material from which they are made. At the same time, the experimental determination of the damping ability of a material is a more difficult task than the determination of any other mechanical characteristic. In recent years, modern composite materials have been increasingly used in civil and transport construction. The main feature of composite materials in terms of damping ability is the combination in a single conglomerate, which is characterized by emergence, of the components (phases of the composite), which have different elastic and damping properties. However, the damping of a structure has a significant effect on its dynamic behavior, for example, the phenomenon of aerodynamic instability of galloping is associated with negative aerodynamic damping. One of the aim of the paper is to analyze the effect of composite materials damping on bridge aerodynamic stability. A series of experiments was carried out to assess the dynamic behavior of a bridge in a wind flow at various levels of damping. At the first part we discussed the damping capacity of different materials, it was shown that composite materials have better dissipative properties in comparison with metals and their alloys composite materials. At the second part we have considered the different ways for determination of the damping capacity of the material. Further we provided a series of experiments to analyze the effect of composite materials damping on bridge aerodynamic stability.