Advancement of cohesive crack approach to model shrinkage and load induced cracking in multi-phase soils. Soil cracking affects many engineering applications and infrastructure. It is also recognised that the impending climate change can affect the severity of soil cracking. Despite this, there is lack of progress in this area and significant knowledge gaps exist. This project will provide new knowledge and better design and management tools.
Discovery Early Career Researcher Award - Grant ID: DE140100903
Funder
Australian Research Council
Funding Amount
$394,020.00
Summary
Advanced numerical and physical modelling of dynamically penetrating anchors for deep water oil and gas developments. Dynamically penetrating anchors (DPAs) are a recent and promising mooring concept for deep water oil and gas developments. Yet, the application of dynamically penetrating anchors remains limited due to a lack of understanding of their performance during dynamic installation and monotonic pull-out and because there are no robust models to simulate these processes. This project wil ....Advanced numerical and physical modelling of dynamically penetrating anchors for deep water oil and gas developments. Dynamically penetrating anchors (DPAs) are a recent and promising mooring concept for deep water oil and gas developments. Yet, the application of dynamically penetrating anchors remains limited due to a lack of understanding of their performance during dynamic installation and monotonic pull-out and because there are no robust models to simulate these processes. This project will advance numerical and physical models of dynamically penetrating anchors impacting the seafloor and embedding into the sediment, and rotating to align with the mooring line upon pull-out. This will lead to accurate predictions for both installation and operation. Robustness will be ensured by accounting for the actual failure mechanisms, high strain rates, potential anchor diving and characteristics of calcareous silt.Read moreRead less
Investigation of alternative footing shapes to mitigate instabilities during installation of offshore drilling platforms. Spudcan footings are used to support three legged mobile drilling rigs, exploring and extracting oil and gas in water depths of up to 150 metres. Despite efforts by the industry to minimise the risks during rig installation, punch-through incidents (i.e. unexpected rapid penetration of the footings) and bending of the leg whilst installing the spudcan next to a footprint (poc ....Investigation of alternative footing shapes to mitigate instabilities during installation of offshore drilling platforms. Spudcan footings are used to support three legged mobile drilling rigs, exploring and extracting oil and gas in water depths of up to 150 metres. Despite efforts by the industry to minimise the risks during rig installation, punch-through incidents (i.e. unexpected rapid penetration of the footings) and bending of the leg whilst installing the spudcan next to a footprint (pockmark from previous rig installation) continue to occur at an increasing rate, causing economic loss of $5 to50 million per incident. Combining advanced physical and numerical modelling, this project aims to develop optimised spudcan shapes, and corresponding design approaches and guidelines, to mitigate these risks, ensuring safe installation of rigs in hazardous regions.Read moreRead less
Estimation of spudcan penetration resistance in stratified soils directly from field penetrometer data and quantification of punch-through risk. Foundations for mobile drilling rigs exhibit significant failure rate in the offshore oil and gas industry, which contributes $22 billion annually to the Australian economy. The project will develop a robust design approach for these foundations, based on field penetrometer data and accounting for the highly stratified nature of offshore sediments.
Dynamic evolution of submarine slides and consequences for offshore developments. Oil and gas developments in deep water are at considerable risk from submarine landslides, which may be orders of magnitude larger than onshore landslides. The project will develop new approaches for modelling the initiation and flow kinematics of submarine slides with the aim of quantifying impact forces on offshore infrastructure.
Crusty Seabeds: From (Bio-)Genesis To Reliable Offshore Design. The project aims to make deep water oil and gas developments safer and cheaper by understanding better the unique seabed ‘crust’ conditions that occur in Australian waters. By studying the biogenic, structural and mechanical properties of deepwater crusts in more detail than can be done in ‘live’ oil and gas projects, this project expects to make a step change in the understanding of these seabed crusts. Expected outcomes of this pr ....Crusty Seabeds: From (Bio-)Genesis To Reliable Offshore Design. The project aims to make deep water oil and gas developments safer and cheaper by understanding better the unique seabed ‘crust’ conditions that occur in Australian waters. By studying the biogenic, structural and mechanical properties of deepwater crusts in more detail than can be done in ‘live’ oil and gas projects, this project expects to make a step change in the understanding of these seabed crusts. Expected outcomes of this project include developing new seabed investigation and design approaches for these soils. This should provide significant benefits, by facilitating the design and installation of low-risk, yet low cost seabed infrastructure (e.g. pipelines, risers, shallow foundations etc.) in these problematical seabed typesRead moreRead less
Predicting scour and scour-induced settlement of subsea infrastructure. This project aims to develop improved predictions and understanding of the potential and extent of scour and scour-induced settlement of subsea infrastructure on mobile seabeds. This is expected to enable scour and settlement to be accounted for directly in engineering stability and serviceability design, overturning current practice which ignores both effects on the basis of using scour protection and costly maintenance and ....Predicting scour and scour-induced settlement of subsea infrastructure. This project aims to develop improved predictions and understanding of the potential and extent of scour and scour-induced settlement of subsea infrastructure on mobile seabeds. This is expected to enable scour and settlement to be accounted for directly in engineering stability and serviceability design, overturning current practice which ignores both effects on the basis of using scour protection and costly maintenance and remediation. Development of accurate predictions is expected to be achieved through physical model testing, numerical modelling and analysis of field data. Predictions should improve subsea reliability and lead to omission of scour protection in some situations, increasing international competitiveness of our offshore oil and gas industry.Read moreRead less
Vortex and force characteristics of inclined offshore cylindrical structures in oscillatory flows. Understanding the effects of the inclination angle of an offshore cylindrical structure on hydrodynamic loads in waves is vitally important for safety and longevity of these structures. The project outcomes will be invaluable in minimising the chances of structural failure and enhancing Australia's capabilities in hydrodynamic research.
Local scour below offshore pipelines on calcareous sediments. This project will improve predictions of erosion around subsea structures in calcareous sediment, allowing potential pipeline self-burial. This will reduce the considerable costs currently spent on pipeline stabilisation and increase the viability of Australia's offshore resources and the competitiveness of the Australian oil and gas industry.
Hydrodynamic forces on small diameter pipelines laid on natural seabed. This project aims to improve predictions of hydrodynamic forces on small submarine cables and pipelines through comprehensive experimental modelling at 1:1 scale coupled with development of predictive numerical models. The focus will be on forces in unsteady flows. Present industry guidelines do not make allowance for potential reductions in forces for small diameter pipelines whose diameters are a similar length to the effe ....Hydrodynamic forces on small diameter pipelines laid on natural seabed. This project aims to improve predictions of hydrodynamic forces on small submarine cables and pipelines through comprehensive experimental modelling at 1:1 scale coupled with development of predictive numerical models. The focus will be on forces in unsteady flows. Present industry guidelines do not make allowance for potential reductions in forces for small diameter pipelines whose diameters are a similar length to the effective seabed boundary layer, thereby leading to overly conservative and costly stability design. Results from the experimental program and numerical model developed are expected to be used to improve the current industry design guidelines.Read moreRead less