Release Time:2019-03-09  Hits:

Indexed by: Journal Article

Date of Publication: 2012-03-01

Journal: EARTHQUAKE ENGINEERING AND ENGINEERING VIBRATION

Included Journals: EI、SCIE

Volume: 11

Issue: 1

Page Number: 139-147

ISSN: 1671-3664

Key Words: multi-directional transmitting artificial boundary; viscous-spring artificial boundary; saturated soil foundation; Biot's equations

Abstract: A new artificial boundary model based on multi-directional transmitting and viscous-spring artificial boundary theories is proposed to absorb stress waves in a saturated soil foundation in dynamic analysis. Since shear waves (S-waves) are the same in a saturated soil foundation and a single-phase medium foundation, a tangential visco-elastic boundary condition for a single-phase medium foundation can also be used for saturated soil foundations. Thus, the purpose of the artificial boundary proposed in this paper is primarily to absorb two types of P-waves in a saturated soil foundation. The main idea is that the stress of the P-waves in the saturated soil foundation is decomposed into two types. The first type of stress, sigma (ra) , is absorbed by the first artificial boundary. The second type of stress, sigma (rb) , is balanced by the stress generated by the second artificial boundary. Ultimately, both types of P-waves (fast-P-waves and slow-P-waves) are absorbed by the artificial boundary model proposed in this paper. In particular, note that the fast-P-waves and slow-P-waves are absorbed at the position of the first boundary. Thus, the artificial boundary model proposed herein can simultaneously absorb P-fast waves, P-slow waves and shear waves. Finally, a numerical example is given to examine the proposed artificial boundary model, and the results show that it is very accurate.