Emerging Geohazards research group
Welcome to the website for the Emerging Geohazards research group.
Who are we?
We, at the Emerging Geohazards research group, study the mechanisms of modern-day ground hazards, and their early prediction, prevention, mitigation and recovery through a new generation of technologies which are citizen-centric, more tailored, less intrusive and more courteous to the natural ground systems. Our works are in response to the steep rise (at worryingly escalating rates) in the number of fatalities and extent of economic losses originated from ground-related hazards across the globe and particularly in urban areas. This sheer scale questions the effectiveness of our current and conventional ground engineering methods.
Why what we do matters?
An increasing number of people are residing in flood zones and river banks, brownfield sites and abandoned mine lands, on problematic coastal grounds including liquefiable sands and soft clays, on the flanks of active volcanoes and tailing dams, and in major earthquake zones. These ground conditions generate risks that are often inter-connected and may lead to cascading disasters. In addition to challenges with problematic grounds, the climate emergency and poor ground management has led to a new stream of problems, challenges that our knowledge fails to predict if, where and when they occur. We conduct blue skies and practical research within the framework of problematic soils and in the context of four work streams.
How can you work with us?
Our laboratories are based in London (UK), Bloemfontein (South Africa), Tainan City (Taiwan) and Vienna (Austria). The teams interest fit four main work streams. If you are interested in any of our four main work streams and wish to join us as sabbatical researchers, PhD students or collaborators, let us know and we will be happy to arrange welcoming you in one of our laboratories in England and South Africa, or our partner teams in China, Taiwan and Austria.
Work Stream 1. Cause: The risk of non-authigentic polymorphs
Whilst the ground engineering practice has a fair understanding of classic ground hazards, it is confused by emergence of new strain of problems in grounds, at times and locations that their occurrence is generally unlikely. Among many influencing factors, we have identified anthropogenic alterations to the total environment (atmosphere, biosphere, lithosphere) as ‘new’ drivers. These are as the consequence of urban sprawl, and degradation of ground natural functions (i.e. ecosystem service provision) with ubiquitous footprints in soil packing quality, fatigue and formation of non-authigenic polymorphs of cementitious minerals, all causing uncertainty, anomalies and abnormal spatial variability of soil properties. Here, the emphasis is on the modern-day grand challenges. We argue that whilst the identity of many young non-authigentic mineral polymorphs and their association with geohazards may be known, in many cases their function in todays’ dynamic total environment remains obscure. New knowledge is achieved predominantly through physical modelling, advanced micro-analytical measurement and micro-to-macro approach with emphasis on fatigue, static flow and anisotropic behaviour of natural, engineered and reinforced soils within the tenets of our recently developed structure-based soil model that is exclusively written for young sediments.
Within this theme and in bullet points, we have interest in:
- Young re-precipitated carbonates, their shape, structure and hydromechanical behaviour
- Concept of double porosity
- Structure-based behaviour of soils
- Mineral dissolution
- Environmental controls on particle-level events
Work stream 2. Mechanisms: New tools to decode the hazard mechanisms
At the heart of our works sit identification of mechanisms of abrupt ground movements in young and heavily disturbed soils, and also secondary hazards that follow, including anthropogenic aerosols and dust flux, carbon sequestration, mineralisation and metastability of young cementitious minerals; with recent emphasis on fatigue, static flow and anisotropic undrained behaviour in young deposits, that plague the built environment. We have developed and deployed a suite of soft tools, hard tools and micro-prototyping methods (to simulate the natural syngenetic and epigenetic earth processes). Our tools enable us to re-generate the earth processes at laboratory scale and assist us to better understand the present-day shallow soils, to physically simulate the emerging total environments, and to re-conceptualise the fundamental soil mechanics principles to explain some of the soil abnormal behaviours. In short and within the tenets of this theme are interests lie in:
- Modern dust and aerosols
- Peat and organic soils
- Carbon sequestration and calcareous soils
- Dynamic and anisotropic behaviour
Work stream 3. Solutions: New soft and hard preventive and corrective technologies
We use in-house developed soil models to offer explanation to systematic stress-strain anomalies in some unsaturated, open-packed bi-modal soils. In the past two years, our in-house constitutive model has been successfully refined and adapted to a range of soils (and peat) reinforced with a new generation of fibres, binders and fillers. These include a range of Biogenic (e.g. decayed plant rootlets), Inorganic (including an amalgam of polybutadiene, polyisoperne, elastomers and styrene-butadiene), Organic (e.g. food production wastes), Pseudo-biogenic (we call these Anthroportācarbs), and Virgin mineral matters, many of which are available, naturally, in shallow grounds. In this, we share interest with workers studying natural inspired self-healing technologies.
The new fibres are courteous to the soil health and ecosystem service functions and can be deployed as ‘tailored-for-problem’ alternative additives to ‘unlock’ the potentials of natural problematic grounds. The overarching vision is developing and deploying new technologies, to revitalise and restore the symbiosis between natural systems and engineering interventions, and to ensure interventions are adaptable to emerging environments. In short, our interest within this theme of works include:
- Natural and recycled fibres in soil
- Exploitation of organic and biogenic substances
- Less-intrusive ground engineering
- Soil chemistry
- Structure-based suction-controlled soil properties
- Constitutive models for bimodal soils
Work stream 4. Reach and Change: Bottom-up change of perception
We adopt a citizen-centric dissemination strategy to enhance global preparedness and response. In addition to standard dissemination, we deliver international endorsed CPD workshops (SAICE, ICE accredited across a number of UK and South African universities), and end-user direct engagement. In the latter case, to capture and record the personal experience of and response to emerging geo-hazards, combination of open discussion, physical modelling demonstration and drawing is adopted as the communication vehicle: To guarantee the governance and effective implementation of policies, we bring in human experience of events into design of next generation remedial engineering measures as vehicle for co-producing the shared knowledge. In this and via a radically new pedagogical strategy, a platform is launched for people across Free State South Africa and South East England to share their personal experience of modern ground hazards that has affected their lives through a suite of instruments including song, picture drawing and storytelling.