Continuum Mechanics and Computational Geomechanics

Qi ZHANG 張琦

Assistant Professor 助理教授 博士生導師

Department of Civil and Environmental Engineering 土木與環境工程系

University of Macau 澳門大學

Official webpage: https://www.fst.um.edu.mo/people/qzhang/; https://www.fst.um.edu.mo/cee/acadstaff/; https://www.fst.um.edu.mo/people/academic-staff/

Contact

Feel free to stop by my office at E11-3009 if you are interested in my research. For potential Ph.D. students or 碩士想進組的澳大學生, please make sure you have obtained a good grade in calculus, linear algebra, and probability, for example, you should know at least 70% of the mathematics here. The university general guidelines for applying Ph.D. programs are posted here. The current university scholarship (for new incoming Ph.D. students) type is called UM PhD Teaching Research Assistant. Previous experience in numerical modeling is greatly appreciated.

The University-Funded Postdoctoral Fellow information could be find here.

請注意：國家留學基金委不支持從內地前往香港和澳門地區進行聯合培養（博士和博後都不行）！

Brief biography

Qi Zhang received his M.Sc. and Ph.D. in Civil and Environmental Engineering (area of Mechanics and Computation) from Stanford University under the supervision of Professor Ronaldo I. Borja. Before joining the University of Macau, he worked as a Research Assistant Professor in collaboration with Professor Zhen-Yu Yin.

張琦於斯坦福大學取得碩士和博士學位（計算力學方向），師從 Borja 教授。在入職澳門大學之前，他曾擔任香港研究助理教授，並與尹振宇教授合作。

Academic outreach/service

  1. 2025年粵港澳大灣區“未之星”訓練營（華南理工大學、香港大學、澳門大學） [WeChat post]
  2. Special issue editor of several SCI journals
  3. Reviewer for many prestigious geomechanics journals such as Géotechnique, Acta Geotechnica, and RMRE
  4. Youth Editorial Board of AGER journal (2021, 2022)
  5. Youth Editorial Board of Rock Mechanics Letters (2025)

Academic awards

Research interests

My research interests span several areas:

  • Computational Poromechanics. I am interested in understanding and controlling the fundamental mechanical processes that determine the formation and recovery of earth resources from sedimentary rocks to achieve energy and environmental sustainability.
  • Data-driven approach for engineering. Statistical learning methods are used to help identify potential hazards in the coal mining and tunneling process such as water inrush and overburden failure.
  • Physics-Informed Neural Network for geomaterials. One of the promising research direction that I am trying to work on is FEM/FVM Discretization-Guided Machine Learning in complex geomaterials or nonlinear continuum mechanics.
More about shale poromechanics

Research demo

I. Double porosity media 什麼是雙重孔隙介質？

實際的雙重孔隙土壤樣品（附有掃描電鏡圖像）以及雙重孔隙介質的示意圖，其中包含多個不同的長度尺度，它們之間滿足 LM, Lm ≪ LREV ≪ L. 在每個宏觀物質點上，同時存在兩個壓力場 pM 和 pm

II. Double porosity media poroelastic coefficients derivation 雙重孔隙介質多孔彈性常數推導（特別針對各向異性材料）

  • Mixture theory 混合物理論法
  • Phenomenological approach 唯象法

III. Double porosity media hydromechanical coupling (time scale difference) 雙重孔隙介質流固耦合（時間尺度差異）

  • Transversely isotropic equivalent fracture permeability 裂縫滲流各向異性
  • Low-velocity non-Darcy flow of rock matrix 基岩低速非達西滲流

IV. Thermo-hydro-mechanical coupling in porous media (pipeline penetration simulation) 多孔介質熱流固耦合 (管道貫入模擬) 100℃ pipeline / 5℃ soil

  • A video (zoomed-in area surrounding the pipeline) showing how incremental equivalent plastic strain (Incremental PEEQ) changes throughout the entire penetration process (frictionless/smooth contact and Mohr-Coulomb plasticity model are adopted here)
  • A video showing how excess pore water pressure (Excess PWP) changes throughout the entire penetration process (frictionless/smooth contact and Mohr-Coulomb plasticity model are adopted here)

Publications in chronological order

  1. Zhang Q, Sheng X. Novel finite element modeling of coupled fluid dynamics and solid deformation in layered unconventional shale.
  2. Zhang Q, Sheng X, Li X. Multiphysics modeling of gas production from GHBS considering sand detachment and elastoplasticity.
  3. Zhang Q (Sole author). Numerical simulation of isothermal Masuda’s experiment on methane hydrate-bearing sediments: a new benchmark initiative. Under review.
  1. Shao J, Zhang Q. Theoretical and numerical studies on hydro-mechanical wing crack propagation in pre-cracked rock materials considering T-stress. 2025. doi: 10.70425/rml.202504.26
  2. Zhu X, Zhang Q, Liang M, Zhang W. Mining-induced damage evolution and infiltration failure in deep mudstone-sandstone interbedded strata. 2025. doi:10.1016/j.rineng.2025.107095.
  3. Lin J, Yan X, Wang E, Zhang Q, et al. A Layer-Specific Constraint-Based Enriched Physics-Informed Neural Network for Solving Two-Phase Flow Problems in Heterogeneous Porous Media. Petroleum Science 2026. doi:10.1016/j.petsci.2025.07.008.
  4. Yan X, Lin J, Ju Y, Zhang Q, et al. A Finite-Volume Based Physics-Informed Fourier Neural Operator Network for Parametric Learning of Subsurface Flow. Advances in Water Resources 2025; 205:105087. doi:10.1016/j.advwatres.2025.105087.
  5. Sheng X, Zhang Q, Shi H. A micromechanical study of shear-weakening characteristics of granular flow in a torsional shear cell. Computers and Geotechnics 2025; 189:107591. doi:10.1016/j.compgeo.2025.107591. (Work done by Ph.D. candidate at UM)
  6. 朱先祥，張琦，馬俊鵬，王永軍，孟凡貞。漿-水置換效應下含水砂層滲透注漿擴散機制 Diffusion mechanism of seepage grouting in water-bearing sand layer under slurry-water replacement effect. 岩土力學 Rock and Soil Mechanics 2025; 46(06): 1957-1966. doi:10.16285/j.rsm.2024.0958. (岩土三大刊：岩土力學、岩土工程學報、岩石力學與工程學報)
  7. Zhang Q, Yan X, Wang X. Numerical modeling of gas flow and solid deformation in unconventional anisotropic shale. Computers and Geotechnics 2025; 187:107441. doi:10.1016/j.compgeo.2025.107441. (Featured work) [code]
  8. Zhu X, Zhang Q, Hu D, Zhong L, Li Z, Jin L. Composite solid sand reinforcement grouting material preparation and diffusion characteristics of slurry-water replacement grouting. Case Studies in Construction Materials 2025; 22:e04213. doi:10.1016/j.cscm.2025.e04213.
  9. Wu X-H#, Zhang Q#, Feng W-Q, Yin Z-Y, Fang H. Enhanced THM coupling for anisotropic geomaterials and smoothed-FEM simulation. International Journal of Mechanical Sciences 2025; 290:110087. doi:10.1016/j.ijmecsci.2025.110087. (Featured work, see WeChat post in Chinese)
  10. Tang Z-Q, Zhou X-W, Jin Y-F, Yin Z-Y, Zhang Q*. A novel coupled bES-FEM formulation with SUPG stabilization for thermo-hydro-mechanical analysis in saturated porous media. Computers and Geotechnics 2024; 173:106454. doi:10.1016/j.compgeo.2024.106454.
  11. Zhu X, Zhang Q, Zhang W, Jin L, Li Z. Solid waste slurry grouting transformation mechanism of loose sand layer based on slurry-water replacement effect. Physics of Fluids 2024; 36(7):073330. doi:10.1063/5.0217551.
  12. Shao J, Zhang Q, Zhang W. Evolution of mining-induced water inrush disaster from a hidden fault in coal seam floor based on a coupled stress – seepage – damage model. Geomechanics and Geophysics for Geo-Energy and Geo-Resources 2024; 10(1). doi:10.1007/s40948-024-00790-w.
  13. Zhang Q, Yin Z-Y, Yan X. Anisotropic continuum framework of coupled gas flow – adsorption – deformation in sedimentary rocks. International Journal for Numerical and Analytical Methods in Geomechanics 2024; 48(4):1018–1045. doi:10.1002/nag.3674. (A new shale gas apparent permeability model) [code]
  14. Zhang Q, Yin Z-Y, Yan X. Material Constants of Anisotropic Poroelasticity and Its Impacts on Shale Gas Production. Energy & Fuels 2023; 37(23):18722–18734. doi:10.1021/acs.energyfuels.3c02656. (Featured work) [code]
  15. Yin Z, Zhang Q, Laouafa F. Multiscale multiphysics modeling in geotechnical engineering. Journal of Zhejiang University-SCIENCE A 2023; 24(1):1–5. doi:10.1631/jzus.A22MMMiG. (Editorial)
  16. Wang Z, Zhang Q, Zhang W. A novel collaborative study of abnormal roof water inrush in coal seam mining based on strata separation and wing crack initiation. Engineering Failure Analysis 2022; 142:106762. doi:10.1016/j.engfailanal.2022.106762.
  17. Zhang Q, Wang Z-Y, Yin Z-Y, Jin Y-F. A novel stabilized NS-FEM formulation for anisotropic double porosity media. Computer Methods in Applied Mechanics and Engineering 2022; 401:115666. doi:10.1016/j.cma.2022.115666. (Featured work) [code]
  18. Zhang Q, Yan X, Li Z. A mathematical framework for multiphase poromechanics in multiple porosity media. Computers and Geotechnics 2022; 146:104728. doi:10.1016/j.compgeo.2022.104728.
  19. Wang Z, Zhang Q, Shao J, et al. Mathematical Evaluation on the Control of Mining-Induced Ground Subsidence in Thick Loose Strata. ACS Omega 2021; 6(50):34596–34605. doi:10.1021/acsomega.1c04970.
  20. Zhang Q. Strip load on transversely isotropic elastic double porosity media with strong permeability contrast. Advances in Geo-Energy Research 2021; 5(4):353–364. doi:10.46690/ager.2021.04.02.
  21. Zhang Q, Wang Z. Spatial prediction of loose aquifer water abundance mapping based on a hybrid statistical learning approach. Earth Science Informatics 2021; 14(3):1349–1365. doi:10.1007/s12145-021-00640-3.
  22. Zhang Q, Yan X, Shao J. Fluid flow through anisotropic and deformable double porosity media with ultra-low matrix permeability: A continuum framework. Journal of Petroleum Science and Engineering 2021; 200:108349. doi:10.1016/j.petrol.2021.108349.
  23. Zhang Q, Borja RI. Poroelastic coefficients for anisotropic single and double porosity media. Acta Geotechnica 2021; 16(10):3013–3025. doi:10.1007/s11440-021-01184-y.
  24. Yan X, Sun H, Huang Z, Liu L, Wang P, Zhang Q, Yao J. Hierarchical Modeling of Hydromechanical Coupling in Fractured Shale Gas Reservoirs with Multiple Porosity Scales. Energy & Fuels 2021; 35(7):5758–5776. doi:10.1021/acs.energyfuels.0c03757.
  25. Shao J, Zhang Q, Zhang W, Wang Z, Wu X. Effects of the borehole drainage for roof aquifer on local stress in underground mining. Geomechanics and Engineering 2021; 24(5):479–490. doi:10.12989/GAE.2021.24.5.479.
  26. Zhang Q, Chen Y, Yang Z, Darve E. Multi-Constitutive Neural Network for Large Deformation Poromechanics Problem. In: Proceedings of the Machine Learning and the Physical Sciences Workshop, 34th Conference on Neural Information Processing Systems (NeurIPS), Virtual (Online) 2020. [poster]
  27. Wang Z, Zhang Q, Shao J, Zhang W, Wu X, Zhu X. New Type of Similar Material for Simulating the Processes of Water Inrush from Roof Bed Separation. ACS Omega 2020; 5(47):30405–30415. doi:10.1021/acsomega.0c03535.
  28. Zhang Q. Hydromechanical modeling of solid deformation and fluid flow in the transversely isotropic fissured rocks. Computers and Geotechnics 2020; 128:103812. doi:10.1016/j.compgeo.2020.103812.
  29. Shao J, Zhang Q, Wu X, Lei Y, Wu X, Wang Z. Investigation on the Water Flow Evolution in a Filled Fracture under Seepage-Induced Erosion. Water 2020; 12(11):3188. doi:10.3390/w12113188.
  30. Yan X, Huang Z, Zhang Q, Fan D, Yao J. Numerical Investigation of the Effect of Partially Propped Fracture Closure on Gas Production in Fractured Shale Reservoirs. Energies 2020; 13(20):5339. doi:10.3390/en13205339.
  31. Zhu X, Zhang Q, Zhang W, Shao J, Wang Z, Wu X. Experimental Study on the Basic Properties of a Green New Coal Mine Grouting Reinforcement Material. ACS Omega 2020; 5(27):16722–16732. doi:10.1021/acsomega.0c01626.
  32. Shao J, Zhang Q, Sun W, Wang Z, Zhu X. Numerical Simulation on Non-Darcy Flow in a Single Rock Fracture Domain Inverted by Digital Images. Geofluids 2020; 2020:8814327. doi:10.1155/2020/8814327.
  33. Zhang Q, Chen Y, Yang Z. Data Driven Solutions and Discoveries in Mechanics Using Physics Informed Neural Network. Stanford University CS 229 Project, Spring 2020 [link]
  34. Zhang Q, Choo J, Borja RI. On the preferential flow patterns induced by transverse isotropy and non-Darcy flow in double porosity media. Computer Methods in Applied Mechanics and Engineering 2019; 353:570–592. doi:10.1016/j.cma.2019.04.037.
  35. Zhang Q, Zhu H. Collaborative 3D geological modeling analysis based on multi-source data standard. Engineering Geology 2018; 246:233–244. doi:10.1016/j.enggeo.2018.10.001. (本科畢設成果, under the supervision of 朱合華院士)

Open source code repository

FEM and PDE tool for fractured solid: This repository provides a MATLAB-based framework for simulating gas flow and solid deformation in unconventional anisotropic solid. The code is intended for a variety of scenarios and supports multiple fluid types, finite element formulations, and constitutive models.

Point simulation: This repository summarized several elastoplastic constitutive models, which are given in the time-integrated fully implicit form. Some classical stresss point simulations are also provided. Following constitutive models are considered: (1) ideal Drucker-Prager plasticity; (2) Modified Cam-Clay in which the isotropic elastic matrix is updated explicitly; (3) anisotropic MCC model for transversely isotropic rocks such as shale; (4) saturation-dependent anisotropic elasticity.

Useful template for research.

Photos for fun