摘要
研究了冲击回波法用于混凝土棱柱体试件动弹性模量的测试情况,发现测试的波速为理论的一维P波波速,且获取混凝土动弹性模量的方法在本质上与传统的共振法是一致的。采用冲击回波法检测混凝土试件在冻融循环中波速的变化,与共振法测试的自振频率的变化进行对比研究,总结其内在规律,最终换算到相对动弹性模量的下降值来评价混凝土的抗冻性。初步的试验和理论分析的结果表明,利用冲击回波法进行水工混凝土抗冻性检测的方法切实可行,可用于水工混凝土的耐久性评估。
The validity of using the impact-echo method to measure the dynamic elastic modulus of concrete for standard prismatic specimens was studied here.It was found that P-wave speed in a standard prism obtained with the impact-echo test agrees well with the theoretical one-dimensional P-wave speed,and the dynamic elastic moduli obtained using the impact-echo method are essentially equal to those using the conventional transverse resonant frequency method. Here,the impact-echo method was adopted to detect the variation of P wave velocities of concrete specimens with increase in freezing and thawing cycles,it was compared with the variation of the fundamental vibration frequencies of the specimens obtained with the resonance method.The parallel evaluation of the decline of relative dynamic elastic modulus was conducted using these two methods.The experimental results and theoretical analysis showed that using the impact echo method to detect the frost resistance of hydraulic concrete is feasible and the method can be used for durability assessment of hydraulic concrete.
出处
《振动与冲击》
EI
CSCD
北大核心
2014年第8期196-201,208,共7页
Journal of Vibration and Shock
基金
中国水利水电科学研究院科研专项(结集1246)
水利部"948"项目(201301)
关键词
冲击回波法
混凝土
动弹性模量
耐久性
impact echo method
concrete
dynamic elastic modulus
durability
