CGSE academic Dr Shiaohuey Chow has received a University of Western Australia Research Collaboration Award to collaborate with Dr Andrea Diambra of The University of Bristol. The project “Plate Anchors for Offshore Renewable Energy Application: Predicting Cyclic Behaviour in Sand” will use centrifuge and numerical modelling to investigate the behaviour of plate anchors in sandy soils.
Plate anchors have traditionally been used in hydrocarbon exploration to moor large floating structures in deep water clayey soils, but they also provide a promising anchoring solution for the shallow, sandy seabeds typically associated with renewable energy devices.
This new research project will use centrifuge modelling to understand the undrained cyclic capacity of plate anchors in sand. Once the results of the centrifuge modelling have been established, Dr Chow and Dr Diambra will use the University of Bristol’s hardening memory surface (HSM) model to develop and validate a macro-element model that will simulate the progressive deformation and strength changes induced by cyclic loads on plate anchors.
Offshore renewable energy sources have the potential to contribute to meeting increasing global energy demand, and government targets for clean energy.
Laureate Professor Scott Sloan, CGSE Centre Director has been selected in the list of Australia’s Top 100 Most Influential Engineers for 2015, and profiled in the June issue of Engineers Australia magazine.
Mr Wangcheng Zhang, a PhD candidate based at the Centre for Offshore Foundation Systems (COFS), is the inaugural recipient of the Fugro Scholarship in Offshore Geotechnics. The scholarship is designed to assist in addressing key questions relating to design and performance in the field of offshore geotechnics, and to reduce risk by enhancing engineering design across the offshore sector.
Under the supervision of the Fugro Chair in Geotechnics, Professor Mark Randolph, and co-supervised by Dr Dong Wang (COFS) and Professor Sasha Puzrin (ETH Zurich), Wangcheng will explore the initiation of submarine landslides and develop recommendations to improve the identification of zones of the continental shelf break that have increased submarine landslide risk. Submarine landslides are of great concern in deep water oil and gas developments and are also among the most challenging of natural hazard risk to quantify. This is due to difficulties in predicting their occurrence, and their potentially devastating consequences including collision with oil and gas pipelines or the generation of tsunamis.
Fugro and COFS work together to sustain a research group that is committed to supporting Fugro’s activities worldwide. This partnership has put Australia on the global geotechnical map and supports the international geotechnical community and offshore projects in the oil and gas and renewable energy industries.
CGSE PhD student, Mr Jingbin Zheng, has been awarded a 2015-2016 ISOPE scholarship for Outstanding Students. The scholarship is in recognition of outstanding academic achievement and the potential to become a leader in the offshore mechanics and polar engineering field.
Jingbin co-authored the paper Installation of Spudcan Foundations in Layered Soils: Centrifuge Test and Numerical Analysis, with CGSE researchers Shazzad Hossain, Stefanus Safinus, Youngho Kim and Jonghwa Won, Jong-Sik Park and Min Jung Jun from Daewoo Shipbuilding and Marine Engineering in Korea. The paper is being presented at ISOPE 2015.
Jingbin’s PhD topic is on the numerical modelling of spudcan and cone penetration in multilayer soils. Using numerical analyses of spudcan and cone penetration tests, Jingbin is producing practical predictive methods for assessing spudcan penetration resistance in multilayer soils. These include a mechanism-based two-step approach and a CPT-based direct approach. The former predicts spudcan penetration resistance using shear strength parameters derived from laboratory tests, while the latter will provide a direct correlation between spudcan penetration performance and field penetrometer data to provide a first-order estimation for the risk of punch-through failure and thus reducing the time scale and costs of current engineering calculations.
The CGSE would like to congratulate Jingbin on his ISOPE scholarship award.
The Centre is delighted to announce that Laureate Professor Scott Sloan has been elected to a Fellowship of The Royal Society. This scientific academy is the oldest in continuous existence and has included past luminaries such as Sir Isaac Newton, Charles Darwin and Albert Einstein.
Scott is a pioneer of new methods that enable engineers to predict the collapse states of geostructures such as tunnels, dams, highways and foundations. These methods have delivered a new tool for engineers to design cheaper and safer civil infrastructure across the globe. He also pioneered the use of high-order elements for accurate predictions with the standard finite element method, as used in PLAXIS, as well as widely-used algorithms for implementing practical soil models, generating meshes, and solving large sets of finite element equations.
Scott studied for his BEng (Civil, Hons I) and MEngSci Degrees at Monash University, before winning a scholarship from Trinity College to undertake a PhD at the University of Cambridge in 1978. He later won a Rouse Ball Scholarship at Trinity College, which he held for one year. After 3 years as a W W Spooner Fellow at New College Oxford, he returned to Australia in 1984 to take up a lectureship in Civil Engineering at the University of Newcastle. Scott was appointed Director of the 70-strong University of Newcastle Priority Research Centre for Geotechnical and Materials Modelling in 2007 and made a Laureate Professor in 2008. He is also the founding Director of the CGSE which commenced operation in 2011.
Scott has published over 340 refereed papers and delivered over 40 plenary, keynote and invited papers at conferences. He accumulates in excess of 600 Scopus citations per year, and was elected to Fellowships of the Australian Academy of Technological Sciences and Engineering in 2000 and the Australian Academy of Science in 2007.
Three other Australians are amongst the 47 new fellows and 10 new Foreign Members announced by the Royal Society in 2015: a linguist and psychologist, an animal geneticist, and an earth scientist.
Scott’s election means that the CGSE now has the rare distinction of having two Fellows of the Royal Society as Chief Investigators, with Mark Randolph from the UWA being the other.
The President of the Royal Society, Sir Paul Nurse said science and its application are at the core of so many aspects of our modern lives. “From treating infectious diseases, to building safe bridges and tunnels, searching out life on other planets and even vacuuming our living rooms, science helps us understand ourselves better and it makes our lives better.”
A Joint Industry Project (JIP) led by the Centre for Offshore Foundation Systems (COFS), the University of Western Australia (UWA) node of the Centre for Geotechnical Science and Engineering (CGSE), has kicked off with 5 industry participants – Benthic Geotech, Fugro, Shell, Total and Woodside. The JIP, entitled Remote Intelligent Geotechnical Seabed Surveys (RIGSS) will deliver new sensors, tools and engineering design methods that will enable more intelligent and efficient geotechnical seabed surveys.
The aim of the JIP is to advance geotechnical site investigation technology through improved control and instrumentation, new types of sensors – penetrometers and other tools – and new engineering design methods that apply the SI data more directly to geotechnical design. The remote and intelligent sensors will be deployed from a seabed frame or ROV-based platform, or be deployable into box core samples on deck.
These arrangements will allow SIs to be more effective, gathering better geotechnical data and making more efficient use of survey time. The new sensors, including novel penetrometers invented at COFS, will provide more detailed measurements of soil response, through seabed interactions that are more directly relevant to engineering design. For example, a compact instrumented pipe-like penetrometer such as the COFS-developed toroidal device is more suited to the determination of pipe-soil friction factors than the traditional cone penetrometer.
COFS has worked closely with industry for the past 15 years, during which time, Professor Mark Randolph has pioneered the development of new seabed penetrometers including the T-bar and piezoball devices, which are now widely used offshore. This new phase of research, supported by both Operators and Survey Contractors, includes other new penetrometer devices, such as the larger hemiball and toroid devices. These tools are particularly suited to near-surface characterisation for pipelines and shallow foundations.
The RIGSS JIP has 6 Work Packages, targeting different technologies that have been chosen for their potential to impact on survey practice and engineering design. These packages cover (i) control, actuation and acquisition, (ii) surface and deep penetrometers, (iii) free fall penetrometers, (iv) in situ erosion and scour measurements and also (v) blue sky sensors.
The JIP has a particular, but not exclusive, focus on shallow seabed site investigation over extensive areas, such as for pipelines and subsea infrastructure, where low-cost, remotely operated site investigation tools and smart testing techniques offer potential improvements relative to current practice.
The deliverables include recommended practices for planning, executing and interpreting tests using the new sensors, and new methodologies to perform engineering design based on the gathered data. Also, COFS will deliver blueprints of the optimised designs of the new sensors, allowing Contractors to fabricate their own devices, to suit their proprietary equipment.
The COFS researchers are building prototype versions of the new tools that will be proven in the field during the JIP, and will also deliver interpretation routines to allow rapid deployment in offshore practice.
The research will be underpinned by experimental and numerical modelling at COFS, including centrifuge model testing, as well as field-scale trials at Australia’s national soft clay test site, located at Ballina in NSW.
Professor Susan Gourvenec was awarded one of the UWA Vice-Chancellor’s Mid-Career Research Awards for distinguished achievement in research in the engineering field. The award was presented by UWA Vice-Chancellor, Professor Paul Johnson and the Deputy Vice-Chancellor for Research, Professor Robyn Owens at a ceremony celebrating ‘Research Week’.
Susan has established her research career at the Centre for Offshore Foundation Systems (COFS) since joining UWA in 2001. Her research focusses on seabed engineering with particular interests in optimization of foundations for floating facilities and subsea infrastructure. Her research has led to awards from the International Society of Soil Mechanics and Geotechnical Engineering, the Australian and New Zealand Geomechanics Society, the American Society of Civil Engineers and the Canadian Geotechnical Society. Outcomes from Susan’s research have been applied in engineering practice in Australia and overseas and are referenced in international design guidelines. Susan’s research findings are disseminated to undergraduates, postgraduates and industry personnel through her co-ordination and delivery of specialist courses in offshore geotechnics and co-authored text book with Mark Randolph ’Offshore Geotechnical Engineering’. Susan also writes for The Conversation.
The CGSE would like to congratulate Susan on her award and thank her for her contributions to the Centre.
Prof Robyn Owens (UWA), Dr Phil Watson (Fugro) and Mr Peter Burger (Fugro)
The Fugro Chair in Geotechnics aims to develop a sustainable research group, to address key questions related to design and performance within the field of offshore geotechnics, reducing risk and enhancing engineering design within the offshore sector.
The agreement, which also provides funding for three PhD scholarships, was signed by UWA Deputy Vice-Chancellor (Research) Professor Robyn Owens and Dr Phil Watson, Director of Fugro Advanced Geomechanics in Perth and Fugro’s Global Service Line Manager GeoConsulting.
CGSE Deputy Director, Winthrop Professor Mark Cassidy said the partnership between Fugro and the Centre would help ensure research was targeted to solving real world problems.
Dr Watson said the creation of the Fugro Chair in Geotechnics was fully aligned with Fugro’s strategic objective to further expand its global consultancy business.
“This initiative combines the best consultants and researchers with the high quality earth data acquired by Fugro’s geotechnical and survey experts,” he said.
The PhD scholarships aim to facilitate the growth of high quality graduates in offshore geotechnics and engineering, with selected students offered the opportunity to work with Fugro.
Researchers from the ARC Centre of Excellence for Geotechnical Science and Engineering (CGSE), were recognised through two awards presented last week at the annual meeting of the Canadian Geotechnical Society, in Regina Canada. CGSE-authored papers were given the RM Quigley Award for the best paper published in 2013 in the Canadian Geotechnical Journal, and an RM Quigley Honourable Mention as runner-up in this competition.
The papers were lead-authored by University of Western Australia (UWA) PhD graduates, Zack Westgate and Divya Mana and co-authored by their supervisors Professors Mark Randolph, Susan Gourvenec and David White.
As well as the academic recognition of these awards, the research has had impact in industry. Zack’s paper, entitled “Modelling the embedment process during pipe-laying on fine-grained soils” is one of 7 papers from his PhD, which has led to new methods for assessing the embedment behaviour of subsea pipelines that are used widely in industry. After graduating from UWA, Zack joined Perth firm, Advanced Geomechanics (now Fugro AG), and is currently based in Fugro’s Houston office.
“I’m now enjoying the opportunity to transfer the knowledge from my PhD into the design practices used by Fugro on offshore pipeline projects in the US and worldwide” said Zack. His research is cited in the international standards that advise on subsea pipeline design, and has already been applied by Fugro AG on many projects across Australia and worldwide.
Meanwhile, Divya’s paper, entitled “Experimental investigation of reverse end bearing of offshore shallow foundations” has led to design tools that are already being applied to assess potential anchoring systems for large floating oil and gas platforms offshore Australia. Her supervisor, Professor Susan Gourvenec said “Divya’s work focused on the need to develop efficient and reliable anchoring systems for tethered floating structures, which are one solution for accessing Australia’s remote gas fields. I’ve collaborated with Fugro AG to deploy Divya’s research in practice, sizing up foundation systems planned for offshore Australia”.
Steve Neubecker, General Manager GeoConsulting at Fugro AG in Perth, said that their close interaction with The Centre for Offshore Foundation Systems (COFS) at UWA helps to transfer technology rapidly into engineering practice. “The research recognised by these awards has already been applied to projects in Australia and elsewhere, thanks to close collaboration between COFS and Fugro AG. As Australian projects move into deeper water with new types of floating structures and challenging pipeline conditions, novel geotechnical solutions are needed. Our partnership with the university allows us to develop these solutions drawing on the university’s academic strengths and our industry experience – leading to award-winning research and practical engineering solutions that are applicable both offshore Australia and worldwide.”
Fugro AG supports COFS’ research as a Partner Investigator in the Australian Research Council Centre for Excellence in Geotechnical Science and Engineering, of which COFS is the Western Australian node.
Pic: Conleth O’Loughlin (COFS), Senol Ӧzmutlu (Vryhof) and Joris Roozen (Vryhof) with the DEPLA anchor.
An innovative offshore anchor designed by CGSE researchers at The University of Western Australia has already been snapped up by Dutch anchor specialists Vryhof Anchors.
The Dynamically Embedded Plate Anchor (DEPLA) was developed by Associate Professor Conleth O’Loughlin, from UWA’s Centre for Offshore Foundation Systems (COFS), and Dr Mark Richardson, a former PhD student at COFS.
The new anchor design, aimed at mobile drilling units and floating production systems in deep and ultra-deep water, would reduce installation time, costs and materials, Associate Professor O’Loughlin said.
Associate Professor O’Loughlin, who has been researching dynamically installed anchors for the past 10 years, said the anchor was a hybrid system able to sustain significant vertical load and required no external energy source or mechanical operation for installation.
“The anchor resembles a dart, and is installed using gravity, similar to other dynamically installed anchors such as the torpedo pile,” he said.
“However the main part of the ‘dart’, which we call the follower, is removed after the anchor is embedded in the seabed and re-used for the next installation. This leaves the anchor flukes in the seabed, which then become the plate anchor.”
Associate Professor O’Loughlin said global energy company Petrobras had been using a gravity-embedded design since the mid-1990s.
“But the rest of the world has been slow to follow,” he said. “However, one of the limitations of the Petrobras design is that it is not the most efficient – it doesn’t have a lot of capacity relative to its weight.
“The DEPLA boasts all the installation advantages of the torpedo pile, but is much more efficient at resisting load, meaning that much smaller and cheaper units can be used for mooring offshore facilities. Being able to re-use the follower is a significant bonus.”
Vryhof project director Senol Ozmutlu said results indicated the DEPLA exhibited similar behaviour to other dynamically installed anchors during installation, but with much higher capacities and predictability than other dynamically installed anchors that resisted load in friction.
The DEPLA has been tested at model scale in the geotechnical centrifuge facilities at COFS. In these experiments, soil samples are spun at up to 200 times Earth’s gravity, creating stress conditions in the centrifuge sample that are equivalent to tens of metres of the seabed.
The DEPLA was put through its paces in these tests, with the centrifuge data playing a pivotal role in informing the final design concept. This is now a well-accepted approach for obtaining performance data of geotechnical systems and COFS is a world leader, with both beam and drum centrifuge facilities that are heavily utilised by the offshore industry worldwide.
Vryhof’s Business Development Director Leo Bello said the company was extremely happy with the new anchor.
“It will give us a reliable product for ultra-deep water uses that will help our clients reduce their overall mooring cost,” Mr Bello said. “The DEPLA combines the advantages of dynamically installed anchors and vertically loaded anchors and is fully patented.”
The DEPLA has been extensively tested at a quarter scale and it will be now Vryhof ‘s task to engineer and test a full-scale prototype.
“Vryhof was the ideal industry partner to continue development of the DEPLA and we look forward to assisting them in making it a real prospect for the offshore industry” Associate Professor O’Loughlin said.