YAN Xi-dong, LIU Hong-yan, XING Chuang-feng, et al. Variability of elastic modulus in rock under freezing-thawing cycles[J]. 2015, 36(8): 2315-2322.
DOI:
YAN Xi-dong, LIU Hong-yan, XING Chuang-feng, et al. Variability of elastic modulus in rock under freezing-thawing cycles[J]. 2015, 36(8): 2315-2322.DOI: 10.16285/j.rsm.2015.08.026.
Variability of elastic modulus in rock under freezing-thawing cycles
Brittle material such as rock deteriorates subjected to freezing and thawing. It is generally observed that the primary reason of rock deterioration is the water phase transition caused by the change of temperature. Hydraulic pressure is generated by 9% volumetric increase of freezing water in a closed crack
which expands crack
meanwhile water flows into new cracks as the temperature is raised. Therefore
the repeated cycles generate the new damage of rock. The freezing and thawing process of rock is also affected by a number of factors such as the length of cracks
permeability
and heaving stress. Considering the extension length of one single crack subjected to frost heave forces
a formula of the relationship between the macroscopic damage and freezing-thawing cycles is established on the basis of elastoplastic mechanics and fracture mechanics. An analytical model is developed to predict the deterioration degree. The validity of the model is examined by comparing its predictions with the experimental results. The effect of elastic modulus on freezing-thaw cycles
heaving stress and permeability coefficient is also discussed. In addition
the theoretical solutions are compared with the existing experimental results. The conclusions are drawn as follows. Firstly
the crack extension length is dominated by heaving stress and the permeability of rock which increases nonlinearly with the decrease of temperature and the coefficient of permeability. On the other hand
the connectivity increases with increasing crack length
and the permeability of fractured rock mass increases. Secondly
elastic modulus decreases nonlinearly due to freezing-thawing cycles. Thirdly
the initial crack length has great effect on the variability of elastic modulus
according to stress intensity factor theory
the heaving stress decreases as the initial crack length increases
which reduces the elastic modulus to some extent. Finally
by comparing the theoretical results with the experiment data of sandstone under uniaxial compression
it is interesting to note that the results are in good agreement. Although the number of cracks is not affected by the freeze-thaw cycles due to the limitation of the initial assumption
the assumption needs to be improved with the measured data.
Constitutive model research on freezing-thawing damage of rock based on deformation and propagation of microcracks
Derivation and validation of the motion equation for seepage in unsaturated soils
Study of the coupling model of rock elastoplastic stress-seepage-damage (Ⅰ) : Modelling and its numerical solution procedure
Research on multiple chemical grouting experiment of porous sandstone
Experiment study of fractal feature and relationship between fractal dimension and permeability coefficient of gravelly soil in debris flow source area
Related Author
YAN Xi-dong
XING Chuang-feng
LI Chao
WANG Dong-hui
SHAO Long-tan
SUN Yan-pu
DONG Hao
WANG Jun-xiang
Related Institution
Engineering Survey & Design Company of China Railway Seventh Group Co. Ltd.
Department of Engineering Mechanics, Dalian University of Technology
State Key Laboratory of Structural Analysis, Optimization and CAE Software for Industrial Equipment, Dalian University of Technology
Institute of Road and Bridge Engineering, Dalian Maritime University
College of Civil Engineering, Xi’an University of Architecture and Technology