通过采用冲击回波法对设置有不同内部缺陷的混凝土试件进行试验研究, 获得该方法检测混凝土内部缺陷的 识别方法和缺陷范围测定方法。研究结果表明: 采用冲击回波法测试混凝土内部缺陷时, 横向尺寸与缺陷深度比值 小于1B4 的缺陷及缺陷横向尺寸小于50 mm, 且与埋深比值大于1B1 时, 缺陷不易被识别。探头移动过程中观察主 频峰值的变化可以有效测定缺陷范围, 但是缺陷深度的确定与实际试验条件有较大关系。

The impact2echo method w as conducted o n the concrete specimens w ith differ ent inter nal defect s, and the ident ificatio n and determination methods for imper fect ion in co ncr et e specimen w ere obtained. T he test r esults showed that it is difficult to identif y the defects in co ncrete specimen w hen the r at io betw een lat eral dimensions and depth is less than 1B4, the lateral dimen2 sio ns ar e less than 50 mm, and the r atio betw een lateral dimensio ns and dept h is g reater t han 1B1. The sco pe o f defects can be effectively measur ed by o bserv ing the var iatio n o f peak value of frequency; howev er, the determinatio n of defect dept h is r elated to the actual test co ndit ions.

中央级公益性科研院所基本科研业务费专项资金资助(H KY2 JBYW2 2012209)