TY - JOUR

T1 - Phase field modeling of brittle compressive-shear fractures in rock-like materials

T2 - A new driving force and a hybrid formulation

AU - Zhou, Shuwei

AU - Zhuang, Xiaoying

AU - Rabczuk, Timon

N1 - Funding information: The authors gratefully acknowledge financial support provided by the Natural Science Foundation of China ( 51474157 ), and RISE-project BESTOFRAC, Germany ( 734370 ).

PY - 2019/10/1

Y1 - 2019/10/1

N2 - Compressive-shear fracture is commonly observed in rock-like materials. However, this fracture type cannot be captured by current phase field models (PFMs), which have been proven an effective tool for modeling fracture initiation, propagation, coalescence, and branching in solids. The existing PFMs also cannot describe the influence of cohesion and internal friction angle on load–displacement curve during compression tests. Therefore, to develop a new phase field model that can simulate well compressive-shear fractures in rock-like materials, we construct a new driving force in the evolution equation of phase field. Strain spectral decomposition is applied and only the compressive part of the strain is used in the new driving force with consideration of the influence of cohesion and internal friction angle. For ease of implementation, a hybrid formulation is established for the phase field modeling. Then, we test the brittle compressive-shear fractures in uniaxial compression tests on intact rock-like specimens as well as those with a single or two parallel inclined flaws. All numerical results are in good agreement with the experimental observation, validating the feasibility and practicability of the proposed PFM for simulating brittle compressive-shear fractures.

AB - Compressive-shear fracture is commonly observed in rock-like materials. However, this fracture type cannot be captured by current phase field models (PFMs), which have been proven an effective tool for modeling fracture initiation, propagation, coalescence, and branching in solids. The existing PFMs also cannot describe the influence of cohesion and internal friction angle on load–displacement curve during compression tests. Therefore, to develop a new phase field model that can simulate well compressive-shear fractures in rock-like materials, we construct a new driving force in the evolution equation of phase field. Strain spectral decomposition is applied and only the compressive part of the strain is used in the new driving force with consideration of the influence of cohesion and internal friction angle. For ease of implementation, a hybrid formulation is established for the phase field modeling. Then, we test the brittle compressive-shear fractures in uniaxial compression tests on intact rock-like specimens as well as those with a single or two parallel inclined flaws. All numerical results are in good agreement with the experimental observation, validating the feasibility and practicability of the proposed PFM for simulating brittle compressive-shear fractures.

KW - Compressive-shear fracture

KW - Driving force

KW - Hybrid formulation

KW - Phase field model

KW - Rock-like material

KW - Strain decomposition

UR - http://www.scopus.com/inward/record.url?scp=85068561409&partnerID=8YFLogxK

U2 - 10.48550/arXiv.2308.05748

DO - 10.48550/arXiv.2308.05748

M3 - Article

AN - SCOPUS:85068561409

VL - 355

SP - 729

EP - 752

JO - Computer Methods in Applied Mechanics and Engineering

JF - Computer Methods in Applied Mechanics and Engineering

SN - 0045-7825

ER -