Study on strain rate effect of soft rock

Hong Jian Liao, Wu Chuan Pu, Jianhua Yin

Research output: Journal article publicationJournal articleAcademic researchpeer-review

15 Citations (Scopus)


Consolidated undrained triaxial tests were conducted on the specimens of diatomaceous soft rock under different pressures and different loading rates, with stress controlled and strain controlled respectively. The test results show that the soft rock has obvious strain rate effect, and strain rates during loading have notable influences on the strength and deformation of soft rock. On the basis of tests, considering the time-dependent behavior of stress-strain relation of diatomaceous soft rock, a 3D elasto-viscoplastic constitutive model (3D EVP model) is introduced to simulate the strain rate effect of soft rock. All parameters of the model are determined by tests. The stress-strain relationship and the effective stress path of undrained consolidated triaxial tests under different strain rates were simulated using 3D EVP model. The numerical calculation results reflect that the strength, including peak strength and residual strength, of soft rock improves with the increasing of strain rate; and they are consistent with the tests results. The trend of pore water pressure and strain softening of calculation results also show agreement with test results. Through comparing and analysis, it is found that 3D EVP model is effective to describe the strain rate effect of soft rock.
Original languageChinese (Simplified)
Pages (from-to)3218-3223
Number of pages6
JournalYanshilixue Yu Gongcheng Xuebao/Chinese Journal of Rock Mechanics and Engineering
Issue number18
Publication statusPublished - 15 Sep 2005


  • Consolidated undrained triaxial test
  • Constitutive relation
  • Rock mechanics
  • Soft rock
  • Strain rate
  • Time-dependency

ASJC Scopus subject areas

  • Civil and Structural Engineering
  • Geotechnical Engineering and Engineering Geology
  • Geology

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