The research project into debris-flow mitigation is led by Prof Ng. It adopts a holistic approach to tackle scientific challenges and addresses the risk of debris flows in Hong Kong. It comprises research studies in three inter-related key areas of landslide material characterisation from micro to macro-scales and innovative monitoring techniques; investigation of debris flow mechanisms; and risk mitigation measures. The project aims not only to advance our scientific knowledge and understanding of dynamic interaction between debris flows and multiple flexible barriers, but also to develop world-leading design guidelines for multiple flexible barriers against debris flows to reduce the environmental impacts, risks and costs of mitigation measures again debris flows, contributing to the safe and sustainable development of Hong Kong.

To understand mechanism of hazardous and catastrophes debris flow, physical experiment is a good tool to simulate the debris flow behavior. Different scales of flume experiments are carried out worldwide to study the flow characteristics for mitigation.

To diversify debris flow research, a 6 m modernized flume has been constructed to study two-phase poly-disperse flows. The flume can be equipped with different instruments such as load cells, high speed cameras, and pore water pressure transducers. Scale models of different mitigation measures like silt structure and rigid barriers can be installed to study soil-structure interaction.

The flume can also be used to simulate submarine landslides using a large water tank.

Fig.1. A overview of the 6m modernized flume

Fig.2. The HKUST water tank for research into submarine landslides

The below model barrier is the first in the world to capture the prototype response of a flexible barrier for resisting debris flows and rockfall (Ng et al. 2016b). The flexible barrier adopts a patented bilinear spring system to attenuate impact loading. The spring systems are highly variable, and repeatable.

Large-scale flume modeling is being carried out at the Hong Kong Kadoorie Center, as well as in Kunming, China.

Full-scale research into boulders impacting barriers made of various materials is being conducted at Shenzhen.

SU Yuchen, Andy (Mainland China)
Ph.D Topic: Dynamic impacts on rigid barrier with different cushion materials: field tests and numerical simulations
LIU Hengdou, Luis (Mainland China)
Ph.D Topic: Large-scale debris flow interaction with baffles
George Robert GOODWIN (Great Britain)
Ph.D Topic: Multi-phase debris-structure interaction
LIU Haiming (Mainland China)
Ph.D Topic: Large-scale debris flow impact on multiple flexible barriers: field tests and numerical simulations
WANG Chao Mainland China)
Ph.D Topic: Numerical investigation of debris flow mechanisms
KOO Chi Hung, Raymond (Hong Kong)
Ph.D Topic (part-time): Debris flow mobility of multiple-barriers
CHEUNG Ka Ho, Desmond (Hong Kong)
M.Phil Topic: Submarine entrainment
AU Yuk Kit, Kelvin (Hong Kong)
M.Phil Topic: Mechanisms of Interaction between Deflectors and Debris Flows