Li Research Group
Mechanics and physics of complex material systems
Welcome!
We are a multidisciplinary team studying the (complex) mechanics and physics of (seemingly simple) material systems, especially those involving multi-body contact, friction, and fracture. We explore fundamental questions such as: What role does frictional contact play in controlling the macroscopic behavior of granular media? How (and why) does a fast crack behave (the way it does) in the presence of material heterogeneity?​
Rearrangement
Phase transition
Frictional slip
Macro scale
Particle scale
Contact scale
Solid mechanics
Soft matter physics
Optical diagnostics
Our overarching goal is to quantitatively characterize their macroscopic behaviors, understand the underlying small-scale processes, and harness this knowledge for novel engineering applications that enhance the resilience and sustainability of our built environment. To this end, we develop and apply computational and experimental techniques that integrate concepts from solid mechanics, soft matter physics, and optical diagnostics. ​
Our current research areas include the physics of nonlocality in disordered and dense granular media, the mechanics of (dynamic) fracture in (brittle) solids, as well as the mechanics and (inverse) design of meta-materials (or structures) towards the interaction between the natural and built environment.
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Event: A fast crack initiates and propagates in a notched glass-ceramic sample
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Crack speed: ~ 1500 m/s
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Observation length scale: ~1 mm
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Observation time scale: ~1 us
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Framing rate: 5 Mfps
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Technique: Synchrotron-sourced time-resolved X-ray phase contrast imaging (XPCI)​​​