Permafrost

ailway, and can collect and aggregate the transportation resource relatively isolate distributed
in diverse professional works so as to realize the central supervisory and management and get
up to scientific decision ultimately.
Key words:Qinghai-Tibet railway, embankment disasters, permanent maintenance, database,
system design
76
Numerical Simulation of Nonlinear Fracture Failure Process
in Frozen Soil
Yue-dong Wang, Hong-sheng Li
(Department of Engineering Mechanics, Dalian University of Technology, Dalian, P.R. China, 116024)
Abstract: This paper presents a semi-analytical finite element method for the numerical
simulation of nonlinear fracture failure process in frozen soil. The fracture failure process of
frozen soil is nonlinearity and it exist the crack damage zone (MDZ), simplified MDZ as
fictitious crack and assumed there is cementation force on the crack face; the frozen soil
cementation force crack model of nonlinear fracture failure is presented. According to the Paris
displacement formula, the expressions of crack tip opening displacement especially for
three-point band beam (3PB) model and compress model of frozen soil are proposed under the
loading of nonlinear cementation force on the crack face, besides some parameters are provided
for calculating the nonlinear failure process of the frozen soil. Finally the numerical simulation
of 3PB model and compress model of frozen soil is presented. Semi-analytical finite element
method is adopted in the numerical simulation. For 3PB model, the failure process curve at
different temperature and crack tip opening displacement (CTOD) critical value for different
types of frozen soil are given. For compress model, the relation curve CTOD vs. loading and
CTOD critical value for different types of frozen soil are given, too. Compare with the
experimental value in the frozen soil experiment, the result value is accord well.
Key words: frozen soil; nonlinear failure cementation model; numerical simulation
Effects of Seasonal Frozen Soil on Soil-Foundation-Structure
Interaction
Zhaohui (Joey) Yang 1 , Tpal Dutta 2
(1.School of Engineering, Univ. of Alaska 3211 Providence Avenue, Anchorage, Alaska 99508
Email: TUafzy@uaa.alaska.eduUT;
2. Research Associate Environ. & Natural Resources Institute University of Alaska 707 A Street Anchorage,
Alaska 99501)
Abstract: It has been observed that the environmental variables including temperature and
seasonal frozen soil could significantly influence the soil-foundation-structure interaction (SFSI)