Ultrasonic Testing Technology And Its Applications In Quality Testing Of Railway Engineering Research

Ultrasonic test technique, a new developing technique, is one of the test methodswith elastic wave. It is based on elastic wave theory. When an impact is imposed on amedium (rocks, rock mass and concrete structure), a sound wave can be received atdistance. Lots of geotechnical problems can be solved by analyzing the acousticparameter of the sound wave, such as velocity, amplitude and frequency.Firstly, the development status was introduced, and the theory of ultrasonic testwas discussed in the thesis. Secondly, the ultrasonic test technique was applied in theengineering testing of railway. The follow three facets: test depth, concrete intensityand integrity of piles were studied in detail, and some results were obtained.1) A new test method was adopted to locate the cracks in the media. A newformula (Formula 1) was induced.The depth calculated through Formula 1 is in accord with the real depth.2) The ultrasonic-rebound method was applied to test the concrete intensity.Compared with the real intensity, the test results were satisfactory.3) The criterion on quantitating the integrity of piles with ultrasonic perforatewave was constituted. Presently, the pile testing conforms to TB 10218-99 in therailway industry. But, in practice, TB 10218-99 isn't unpractical because of the humaninfluence and operation difficulties. In order to assess the quality of engineering, aquantitative index is required to type the integrity of piles. The author attended toconstitute the index which was permitted in the second conference on the test ofYiWan Railway in April 18 and was applied in the test of total YiWan Railway.By comparing the results of ultrasonic test with ones of traditional methods, theultrasonic test technique is a efficient, precise and economical test methods. It will beapplied widely in railway industry.