Professor Jean Sulem, the head of Laboratoire Navier and local PI of LOC3G at École des Ponts ParisTech, organized the initial secondment meeting with Mr. Hongcheng Jiao (PhD student from BOKU) to formally commence his research stay. The meeting served to introduce academic colleagues from BOKU University and École des Ponts ParisTech, foster academic exchange, and outline the research objectives and plan for the secondment. During this period, Hongcheng Jiao’s research focuses on advancing the understanding of strain localization mechanisms in geomaterials, particularly soils, with an emphasis on Cosserat continuum theory and bifurcation analysis. Professor Sulem provided a comprehensive overview of the theoretical foundations of these advanced models and offered valuable guidance on integrating micropolar formulations with hypoplastic constitutive laws in existing Smoothed Particle Hydrodynamics (SPH) frameworks. In addition, he gave detailed advice on the numerical implementation of micropolar elastoplasticity using the Finite Element Method (FEM), laying a strong foundation for the success of the secondment.
Group photo of Prof. Jean Sulem and Hongcheng Jiao
On 11 October 2024, as part of the Geotech Young Seminar Series, Hongcheng Jiao from BOKU University delivered a presentation at Laboratoire Navier, hosted by Dr. Mathias Lebihain. The seminar attracted an audience of over 50 researchers and scholars from the Navier Lab, reflecting strong interest in advanced numerical methods in geotechnical engineering.
In his talk, Hongcheng Jiao introduced a high-fidelity simulation framework for large deformation problems in geotechnics, based on the Smoothed Particle Hydrodynamics (SPH) method. This mesh-free, particle-based approach is particularly suited for simulating extreme deformation scenarios without the limitations of mesh distortion.
A key feature of the presented work was the implementation of a hypoplastic constitutive model into an in-house SPH code. This model effectively captures the pressure- and density-dependent behavior of granular soils. The presentation highlighted the validation of various constitutive models against experimental data and showcased several numerical examples illustrating the evolution of shear band structures in granular materials undergoing large strains.
The seminar stimulated active discussion and provided valuable insights into the capabilities and future applications of SPH in geotechnical simulations.
Geotech Young Seminar Series: Hongcheng Jiao (BOKU University)
On 6 November 2024, Dr. Mathias Lebihain held a meeting with Hongcheng Jiao to introduce his research field and current projects related to the development of analytical solutions for three-dimensional fracture propagation under multi-physics coupling, and numerical approaches for large-scale three-dimensional crack propagation in composite materials. Dr. Lebihain also provided further suggestions on how to handle multiple length scale parameters in SPH and incorporate micropolar theory.
Group photo of Dr. Mathias Lebihainand Hongcheng Jiao
During his secondment at École des Ponts ParisTech (ENPC), Hongcheng Jiao actively expanded his academic network within the LOC3G consortium. He engaged closely with the research group led by Prof. Jean Sulem, which includes Dr. Mathias Lebihain, Dr. Philipp Braun, Dr. Li Zhang, Dr. Nicholas Anton Collins-Craft, and MSc Zhaochen Xu.
In addition to collaborating with LOC3G partners, Hongcheng also connected with other leading researchers affiliated with the Navier Laboratory at ENPC. Notably, Prof. Yujun Cui and his research team provided valuable feedback and constructive suggestions, contributing to both Hongcheng Jiao’s individual research and the advancement of the broader LOC3G work package.
Hongcheng conducted individual visits and held in-depth discussions with these scholars, gaining valuable insights and inspiring ideas for future research directions. The diverse academic backgrounds of other colleagues at ENPC Navier, such as Dr. Wei Su, Yu Lei, Changhao Qiu, Bobo Jia, Jingyi Leng, Hao Wang, Yiming Ren, Runze Zhang, Mohamed Shahrour, Alec Tristan, Serafim Egorov, among others, further facilitated academic exchange and opened new avenues for interdisciplinary collaboration. Overall, the ENPC Navier Laboratory has proven to be an outstanding institution—not only in the field of geotechnics but also as a hub for interdisciplinary exploration.
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Group photo of Prof. Yujun Cui and Hongcheng Jiao