BEHAVIORS OF WAVE PROPAGATION IN CONCRETE WITH OBLIQUE CRACKS USING ULTRASONIC-PULSE METHOD

• Main Author: 黃智偉
• Other Authors: 吳志興
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/57399260514549228860

碩士 === 國立屏東科技大學 === 土木工程系碩士班 === 90 === This thesis sets up an arrangement of accelerometers connected to a high-resolution of oscilloscope when performing a surface measurement on concrete. The velocity of ultrasonic-pulse wave was estimated by reading the responses of the waves in time domain, As a similar arrangement, the method and calculating formula of depths and angles of the oblique cracks on concrete was proposed. The results showed that the arrangement of the distance between source and the second accelerometer L’=17~23 cm and the distance between two accelerometers L=10~14 cm is a suitable range of measuring pressure wave speed. For the measurement of oblique cracks, the best arrangement is that the distance between the source and accelerometer a is 13 cm when the distances between the sources and crack of two-time measurements are 16 cm and 20 cm.