Kai Liu

Dr. Kai Liu

Department of Engineering Science, University of Oxford, Oxford OX1 3PJ, UK
orcid

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
9 September 2023 in International Journal of Mining Science and Technology
Verified
Journal Article
Open access
ZLZenghui Liu
Zenghui Liu
Kai LiuKai Liu
Kai Liu
XCXuguang Chen
Xuguang Chen
ZMZhengkuo Ma
Zhengkuo Ma
RLRui Lv
Rui Lv
KMKe Ma
Ke Ma

5 May 2021 in Rock Mechanics and Rock Engineering
Verified
Journal Article
Open access
PDF file
Kai LiuKai Liu
Kai Liu
JZJ. Zhao
J. Zhao
Investigation of rock progressive damage under static confinement and strain rates facilitates the generation mechanism of natural fault damage zones. A triaxial Hopkinson bar apparatus is used to perform dynamic triaxial compression tests to examine the damage and degradation process of rocks subjected to multiple impacts. Dynamic mechanical properties are determined under a static triaxial pre-stress of (30, 20, 10) MPa and multiple dynamic loadings, with the repetitive impact velocity of 27 m/s and strain rates from 50 to 150/s. The acoustic characteristics are identified by ultrasonic measurement to qualify the damage values. The micro-crack parameters, including crack area and volumes are detected using synchrotron X-ray micro-computed tomography (μCT) to characterize the progressive damage. In addition, the microcrack orientation, density and fractal dimension are analysed from thin section. Experimental results show that dynamic stress-strain curves can be divided to elastic, nonlinear deformation and unloading phases. Dynamic peak stress, Young’s modulus and ultrasonic wave velocity decrease with increasing impact times. The high frequency of ultrasonic wave is filtered by the induced microcracks. The progressive damage and evolution of fracture networks are associated highly with microcrack initiation, propagation, branching and coalescence. Shear bands are commonly generated in granite, and tensile cracks are dominant in marble, while sandstone is mainly failed by compaction and deformation band. The absorbed energy of rock increases nonlinearly with increasing crack surface and volume. Besides, microcracks propagate primarily along the maximum principal stress; the density and fractal dimension exhibit an anisotropic distribution controlled by true triaxial confinement and dynamic impacts.

1 October 2020 in Construction and Building Materials
Verified
Journal Article
Closed access
PLPengfei Liu
Pengfei Liu
Kai LiuKai Liu
Kai Liu
QZQian-Bing Zhang
Qian-Bing Zhang

10 May 2023 in Composites Part B: Engineering
Verified
Journal Article
Open access
YCYanhong Chen
Yanhong Chen
Kai LiuKai Liu
Kai Liu
ZXZiwen Xu
Ziwen Xu
HLHuifang Liu
Huifang Liu
MLMaria Lißner
Maria Lißner
NPNik Petrinic
Nik Petrinic

10 May 2024 in Engineering Fracture Mechanics
Verified
Journal Article
Closed access
TWTingting Wang
Tingting Wang
LNLeilei Niu
Leilei Niu
Kai LiuKai Liu
Kai Liu
PLPingfeng Li
Pingfeng Li
CTChun'AN Tang
Chun'AN Tang
JYJiang Yu
Jiang Yu

2 May 2024 in International Journal of Rock Mechanics and Mining Sciences
Verified
Journal Article
Open access
Kai LiuKai Liu
Kai Liu
JZJian Zhao
Jian Zhao