Dynamic and seismic property experiments of high damping concrete and its frame models

Abstract

The loss tangent and storage modulus of cement mortar containing treated silica fume and styrene-acrylic are measured. Shaking table tests on three groups of 1/4 models of high damping concrete frames are conducted to compare the effects of reducing vibration. A relationship between the viscosity coefficient of high damping concrete and the damping coefficient of structure is established by analyzing dynamic parameters like damping ratio and frequency, and comparing responses of relative displacement and absolute acceleration. Surface treatment of silica fume and styrene-acrylic emulsion prior to incorporation in a cement mortar increases the loss tangent of the resulting composite by 40–400% as compared to the cement mortar without any admixtures, and the damping ratio of the reinforced concrete is raised by 7%–9%. In addition, a theoretical method of determining the viscosity coefficient of the material on the basis of shaking table test results is put forward.

Keywords

high damping concrete / damping relationship / seismic experiment / surface modification / viscosity coefficient

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