Development of Damping Measuring Instrument and Experimental Research for Hybrid Fiber Reinforced Concretes
复合纤维增强混凝土阻尼测试装置开发与试验研究

Fibers and polymers as the admixtures in the concrete may improve greatly the damping ability of concrete materials.In this paper,firstly the damping relationships of viscoelastic materials via three-point support beam experiment were given under sinusoidal alteration excitation.Secondly,the damping measuring instrument for large-scale materials such as concretes was self developed.Thirdly,the loss tangent and storage modulus for fiber reinforced concretes of 6 different ratios were measured in the range of frequencies(0.5~2.0Hz) by this instrument.Finally,the mechanism of damping reinforcement of the fiber was initially discussed.The experiments show that composite concrete reinforced with polymers and fibers exhibits increases of loss tangent by 80~200% compared to the corresponding value of the ordinary concrete without any admixtures.The internal dissipation of the polymer molecules is the mechanism for improvement of damping energy of ordinary concrete,and the friction on the interfaces between fibers and cement-based materials contributes to the damping of fiber reinforced concrete.