| The concrete ultrasonic wave non-damaged measuring is a kind of new-type non-damaged detection method popularized and applied at home and abroad in recent years. The acoustic transmission law of pouring into one of concrete is developed on the basis of structural concrete acoustics detection technique, through decades years of research, exploration and practising, this new method has been widely used in lots of countries and regions, and it has become a important instrumentality of the concrete non-damaged detection.This text summarizes at first the progress, the history and various kinds of methods of the concrete ultrasonic wave non-damaged detection, then it introduces the basic principles of the ultrasonic wave spreading among concrete medium, and the basic instruments and procedures applied in the experiment. In the text, the relation between different kinds of acoustical parameters of ultrasonic wave and concrete quality will be discussed as well. The text introduce ascensively the criterions used in the judging of concrete defect while applying the time of ultrasonic, and there is also a brief introduction of mainly sentencing to the drama judgement of the main frequency and wave form as sentencing the drama. I validate in the text the accuracy of the concrete ultrasonic wave non-damaged measuring by way of physical experiments. Through data analysis, we can estimate and analyse well the characteristics of the concrete, the main fraquency can be regarded as the supplementary instrumentality, as well as the wave form can be used as a kind of intuitionistic,auxiliary judgement instrumentality, the main fraquancy and wave form have offered a basis for live measuring with real project. By means of the relation between the nature, degree, ranges of concrete body defect and PSD criteria, I set up in the text an expression formula of critical criterion, at the time of several kinds of defects as fault , cavity , and the honeycomb or the cavity clogged by other medium ,etc, through critical judging value and the relational expression between the sizes of various kinds of defects and criterial value, with the comparison between them and their real calculated value, we can estimate the position , nature , and sizeof the defect, which laid the foundation for the quantitative analysis of concrete inner defect and the defeat perform instead.On the basis of the basic principle that ultrasonic wave spreads in the concrete medium and the experiment verified, combining the foundation of the bridge 1 -3 in the highway K16+974 of Luoyang southwest External Loop, use RSMSY5 detecting instrument to detect it. And though velocity of sound,time of sound and wave form etc. use RSMSY5 corresponding procedure to judge it.The piles keep parallel or not is the key and the most important condition of the foundation Nondestructive test. Because of many kinds of influence of factor among actual project, the piles often can't keep parallel and they often keep slope or crooked, its result often brings certain error to the judgement of the foundation quality of the concrete or even judges by accident, misjudging. Because the slope or crooked of the pile will bring error to judgment,therefore in the text I emphasized to analyse the slope or crooked of the piles and corrected them with the method that the contours fit. Analysis results indicate that the piles can't keep parallel will bring a lot of change and influence the judgement. At is it sentence drama to use each asing, prone to major punishment strictly too often, and when use velocity of sound regard as deciding the drama will often be influenced by the fact that piles can not keep parallel and make the wrong judgement. The distortion of the wave form can be as the supplementary means that quality is judged of concrete too, but this kind of judgement method has greater ocular and uncertainty. Therefore, while judging data analysis and result, should combine many kinds of judgements method to analyse synthetically, draw more accurate judgement.
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