Abstract: Thanks to the excellent damping capacity of Duxseal, a newly designed active isolating barrier-Duxseal-WIB is proposed to be used for vibration screening. This barrier is a special type of WIB (wave impeding block) with cylindrical holes and the holes are filled with Duxseal. To investigate the isolation characteristics of Duxseal, numerical studies are firstly performed using a three-dimensional semi-analytical boundary element method (BEM) combined with a thin layer method. Then, the vibration screening effectiveness of the proposed isolating barrier-Duxseal-WIB is verified by field tests. The results show that Duxseal can effectively reduce ground vibrations as an active barrier in the free field, and the effectiveness of vibration isolation at distances far away from the vibration source is relatively better than that near the vibration source. The values of soil parameters have a significant influence on the isolation effectiveness of Duxseal. The isolation effectiveness increases with the increase in diameter, thickness and embedded depth of Duxseal material within a certain range, and the embedded depth is the most critical factor affecting the isolation effectiveness of Duxseal. In addition, the isolation effectiveness at a distance away from the center of the vibration source is higher for Duxseal-WIB than traditional WIB. When we consider a distance of 12 m away from the vibration source as the representative measuring point, the vibration screenings of Duxseal-WIB along the X, Y, and Z directions achieve vibration isolation values of approximately 40%, 39%, and 51%, respectively, under a moving load at a high speed of 250 km/h.

Key words: Duxseal, Duxseal-WIB, active isolation, ground displacement amplitude, amplitude attenuation ratio