E 



H 50 



~ 8 in. 



O A 



^ 6 in. . 



O A 



^ 8 in. 



O ft Sin. ^ 





-o- 



O Transmit 

 A Receive 



O ^ A 



-A O 



-A 



01 



o 





20 30 40 



Path Length Location (in.) 



1 

 18 in. I C 



ES 



J ) ) ) 



E B. 



© 



© © 



© 



© 



Crack locations — octagonal concrete pile 



Figure 19. Measured indirect transit times as a function of position 

 along a cracked prestressed concrete pile. 



47 



