Adelaide

Application of the Full-Field Strain Measurement to Study the Kaiser Effect in Granite Under Indirect Tensile Loading

Ali, Z. (The University of Adelaide) | Karakus, M. (The University of Adelaide) | Nguyen, G. D. (The University of Adelaide) | Amrouch, K. (The University of Adelaide / Mohammed VI Polytechnic University)

OnePetroJune, 2022

ABSTRACT: In-situ stresses and their spatial distribution are important parameters in analyzing and designing underground structures. Deformation rate analysis (DRA) and acoustic emission (AE) are methods of in-situ stress measurement from oriented core, which take advantage of the stress memory in rocks, also known as the Kaiser effect. However, locating point of inflection can be problematic in both DRA and AE analyses due to the rock heterogeneity and complex geological paleo-stress history. This paper investigates the Kaiser effect under indirect tensile loading and the application of full field strain measurement for locating the point of inflection in deformation rate analysis. Cyclic loadings were performed on Brazilian disc specimens of Adelaide black granite and the deformation process was monitored using digital image correlation (DIC) and AE monitoring system. The tests were conducted with and without rotating the disc specimens between the successive loading cycles. The directional dependency of the Kaiser effect was studied by rotating the specimens at 15 degrees interval between 0 and 90 degrees. Strain localization and its influence on the bending point in DRA and stress memory were also investigated. Results show that Kaiser effect exist under indirect tensile loading and rotation of principal axis do not influence the Felicity Ratio (FR). The characteristic DRA curves were influenced by the strain distribution in the specimens which is more pronounced in the localized region. 1. INTRODUCTION The rock stress memory also known as the Kaiser effect is a unique property in rocks to store, retain and reproduce information about the previously applied stresses and strains Kaiser, (1953); Lavrov (2002). This characteristic of the rocks has been widely studied for its application as a non-destructive method for in-situ stress measurement from oriented cored rocks Seto et al. (1999); Villaescusa et al. (2001); Karakus (2014); Ali et al. (2021). However, the viability of the method for stress measurement is still being questioned because there have been studies showing that the Kaiser effect is influenced by numerous factors such as the duration of load applied Filimonov et al. (2001); Lavrov (2003), time delay Kanagawa et al. (1995); Jin et al. (2009), water saturation and heating Yoshikawa and Mogi (1981); Lavrov (2002), rotation of principal axis Stuart et al. (1993) and the coring process Sakaguchi et al. (2002). Moreover, it is also argued that laboratory conditions are different from in-situ conditions, which is more complex and includes not only the compressive stresses but also tensile stresses Lehtonen et al. (2011); Zhang et al. (2017); Chen et al. (2018); Ban et al. (2020). In addition, the complications associated with the stress redistribution after excavation can raise further questions on the application of techniques for stress measurement. The stress zones with the concentration of tensile stress surrounding excavation together with rock tensile properties can play an important role in the stability of the structures. It is for this reason very important to investigate the application of these techniques under tensile loading and understand their characteristics.

56th U.S. Rock Mechanics/Geomechanics Symposium

doi: 10.56952/ARMA-2022-0529

ARMA

ARMA-2022-0529

Country:

Europe (0.68)
North America > United States (0.48)
Oceania > Australia > South Australia (0.29)
Asia > Japan > Kantō > Kanagawa Prefecture (0.24)

Genre:

Overview (0.34)
Research Report > New Finding (0.34)

Industry: Energy > Oil & Gas > Upstream (0.88)

SPE Disciplines:

Well Drilling (1.00)
Reservoir Description and Dynamics > Reservoir Characterization > Reservoir geomechanics (1.00)

Technology: Information Technology > Sensing and Signal Processing > Image Processing (0.50)

Journal of Petroleum TechnologyJanuary, 2021

Thank You, It's Been a Great Ride

One hundred twenty-four speeches and counting, 39 countries visited, millions of excited volunteers (estimated from good feelings that I have had). There are bags under my eyes. What's left of my hair is way grayer than when I started. I've busted two of my four accordions from travel stress, and I'm not sure if I have slept properly in about a year. These are the thoughts that have run through my head as I have had the great honor, rather the great honor, of serving you as your SPE 2018 president.

Adelaide, calgary, Curry, fire make, great group, great honor, great ride, Music, plastic, President, royalty, spe 2018, SPE member

Country:

North America > United States (0.48)
Europe (0.48)
Asia (0.48)

Journal of Petroleum TechnologyJanuary, 2021

Thank You, It's Been a Great Ride

One hundred twenty-four speeches and counting, 39 countries visited, millions of excited volunteers (estimated from good feelings that I have had). There are bags under my eyes. What's left of my hair is way grayer than when I started. I've busted two of my four accordions from travel stress, and I'm not sure if I have slept properly in about a year. These are the thoughts that have run through my head as I have had the great honor, rather the great honor, of serving you as your SPE 2018 president.

Adelaide, calgary, Curry, fire make, great group, great honor, great ride, Music, plastic, President, royalty, spe 2018, SPE member

Country:

North America > United States (0.48)
Europe (0.48)
Asia (0.48)

Spady, Darcy (2018 SPE President)

Community Consensus: Thank You, It’s Been a Great Ride

OnePetroAugust, 2018

President's column My year as your SPE 2018 president Wow. One hundred twenty-four speeches and counting, 39 countries visited, millions of excited volunteers (estimated from good feelings that I have had). Life is grand. … My knees are really sore. There are bags under my eyes. What’s left of my hair is way grayer than when I started. I’ve busted two of my four accordions from travel stress, and I’m not sure if I have slept properly in about a year. These are the thoughts that have run through my head as I have had the great honor, rather the great honor, of serving you as your SPE 2018 president. What a ride! I am so humbled. As I prepare to pass the torch over to my eminently well qualified successor Sami Alnuaim, (a way smarter guy than me) I do so with an immensely thankful heart. I have learned so much. I have been surprised many times. I have been disappointed almost never. What a great bunch of members SPE is proud to call its own. It is hard to describe the gravity and responsibility of leading this society. With almost 160,000 really great people—all contributing something unique, all are really smart and work really hard—it’s no wonder why we are an industry that is one of the most technical on the planet. There are a really smart bunch of folks working in it. From Kavala, Greece, to Adelaide, Australia, I have been constantly surprised with the wonderful people we call members. I am so unworthy to represent such a group. I only hope that I have chaired the board without prejudice and fostered the robust activities that we undertake. People—we, the SPE—set the standard that defines the process that provides the majority of the world’s energy needs. We are the global experts who give the planet home heating, products such as plastic, energy to power our cars, and a myriad of life improvements.

doi: 10.2118/0818-0010-JPT

SPE

SPE-0818-0010-JPT

Adelaide, Board Member, calgary, community consensus, Darcy Spady, fire make, great group, great honor, great ride, plastic, President, reindeer, royalty, Siberia, spe 2018, SPE member, SPE President, Upstream Oil & Gas

Country:

Europe (0.90)
Asia (0.70)
North America > United States (0.48)
Oceania > Australia > South Australia > Adelaide (0.25)

Industry: Energy > Oil & Gas > Upstream (0.51)

Oilfield Places:

North America > United States > Wyoming > Powder River Basin > Sussex Formation (0.89)
North America > United States > Texas > Fort Worth Basin > Duke Field (0.89)

A Conceptual Approach to Modelling Rock Fracture using the Smoothed Particle Hydrodynamics and Cohesive Cracks

Nguyen, Chi T. (University of Adelaide) | Bui, Ha H. (Monash University) | Nguyen, Giang D. (University of Adelaide) | Nguyen, Vinh Phu (University of Adelaide)

OnePetroOctober, 2015

Abstract This paper presents a new numerical approach to modelling rock fracture and fragmentation by combining the advantages of the mesh-free smoothed particle hydrodynamic (SPH) method with a new continuum constitutive model with embedded cohesive cracks. The new constitutive model is capable of providing the links of the continuum mechanics and the non-linear (decohesive) fracture mechanics. It will also possess an intrinsic length scale and hence can automatically capture size effects to produce mesh independent numerical solutions. The proposed numerical approach is illustrated at particle level to show essential features and advantages compared to traditional continuum based constitutive models in the context of SPH simulations. 1 Introduction It has been clear that particle based methods have several advantages over traditional mesh based methods (like the Finite Element Method) for the simulation of fracture, fragmentation and flow of fragmented materials. This is especially true for mining problems such as block caving that usually involves the transition from solid to granular trigged by detonation, which leads to fracture and fragmentation of rock mass, followed by flow of granulated materials under large deformation/displacement conditions. In this study, we propose a new approach to modelling rock fracture, fragmentation and material flow by combining the advantages of a particle method, the Smooth Particle Hydrodynamics (SPH), with a new constitutive modelling approach with embedded cohesive cracks. The key points of the approach are the separation of SPH governing equations and cohesive cracks, together with the development of a new constitutive modelling structure with embedded cohesive zone. In particular, our new constitutive models associated with SPH particles possess enhanced kinematical fields to correctly characterise bulk elastic and cohesive zone phases during fracturing process. This enhanced kinematics is only activated at the initiation of fracture, and once activated, it will help decompose the macro strain associated with an SPH particle into an elastic strain for the bulk and a displacement jump vector across the cohesive surface. This facilitates the implementation in SPH, as the new constitutive structure with embedded cohesive cracks can be treated like any standard constitutive model that takes strain increments as inputs, and returns corresponding stress increments governed by both bulk elastic and cohesive behaviour. This new constitutive modelling approach also possesses an intrinsic length scale and hence can automatically capture size effects, and result in discretisation dependent numerical solutions. Beyond the fracture process, once cohesion is completely lost, SPH algorithms for the approximation of field functions will take place to capture the traction free surface and material separation. In this paper, the theoretical developments together with implementation algorithms for both SPH and constitutive models are described and numerical examples at particle levels are used to demonstrate the potentials of the new approach.

ISRM Regional Symposium - EUROCK 2015

ISRM

ISRM-EUROCK-2015-149

Country:

Europe (0.47)
Oceania > Australia (0.30)

Genre: Overview > Innovation (0.54)

Industry: Energy > Oil & Gas > Upstream (0.49)

SPE Disciplines: Well Completion > Hydraulic Fracturing (1.00)

Technology: Information Technology (0.48)

Three-Dimensional Finite Element Analysis for Rock Fatigue Damage under Dynamic Loading

Karakus, Murat (University of Adelaide) | Ebong, Uwemedimo (University of Adelaide) | Liu, Chen (University of Adelaide) | Zhou, Haomiao (University of Adelaide)

OnePetroOctober, 2015

Abstract In mining operations, rocks are subjected to dynamic loading due to moving vehicles, material loading, drilling-blasting, and mechanical excavations. Therefore, rocks fail prematurely because of the repeated loading-unloading cycles. Variations in the ultimate strength of rocks result in experimental tests difficult to investigate the effect of cyclic loading on rock fatigue behavior. On the other hand, numerical modelling is a feasible option to simulate rock fatigue damage. We simulated rock fatigue damage in three-dimensional finite element analysis (FEA) and introduced a new damage assessment model. Comparison of the results with laboratory test results verified that new damage assessment model is capable of capturing fatigue damage. Based on results from the series of parametric study, it was shown that as maximum loads increase, rock material tends to have shorter fatigue life and is more likely to fail prematurely. Besides, larger amplitudes could lead to shorter fatigue life and earlier rock failure. 1 Introduction Mining is widely accepted as one of the most risky industries (NSW Government 2009). A large variety of potential risks can be observed in mining operations and rock fatigue damage is the most dominant cause (Mortazavi & Molladavoodi 2012) of rock failures. Therefore, rock fatigue behavior has become a major concern for most mining practices and its understanding is necessary to improve safety in the mining environment. It is understood that rock fatigue behaviour differs under various loading conditions (Stavrogin & Tarasov 2001). In this research, the effect of cyclic loading on rock fatigue behaviour is focused on for two reasons. Firstly, the fatigue behaviour of rock materials subjected to cyclic loading is more significant and complicated than that of static loading (Dehmoobed-Sharifabadi & Joseph 2010). Secondly, cyclic loading best represents the stress on rock materials in mining situations which is mainly caused by mining excavations and large mobile mining equipment (Joseph & Dehmoobed-Sharifabadi 2007). This research investigates rock fatigue behavior under various cyclic loading conditions of different amplitudes and maximum loads. A progressive damage model was constructed in order to observe the effects of cyclic loading characters on the rock fatigue behavior in the three-dimensional finite element analysis (FEA). To verify the simulation model, results were compared to those obtained from experimental tests, in which the material properties and scenarios of both the simulation and the laboratory experiments were identical.

ISRM Regional Symposium - EUROCK 2015

ISRM

ISRM-EUROCK-2015-095

Adelaide, amplitude, cyclic loading, damage model, damage variable, deformation, environmental & mining engineering, fatigue damage, fatigue life, loading, loading condition, maximum load, metals & mining, numerical modelling, rock fatigue behavior, rock fatigue damage, rock material, strength, Upstream Oil & Gas

Country:

North America > Canada (0.48)
Oceania > Australia > South Australia (0.17)

Industry:

Materials > Metals & Mining (0.91)
Energy > Oil & Gas > Upstream (0.69)
Government > Regional Government > Oceania Government > Australia Government (0.35)

SPE Disciplines:

Data Science & Engineering Analytics > Information Management and Systems (1.00)
Reservoir Description and Dynamics (0.96)

Determining Strength and Fracture Toughness of Rock from Scratch Tests

He, Xianqun (The University of Adelaide) | Xu, Chaoshui (The University of Adelaide)

OnePetroOctober, 2015

Abstract It has been established that there exist two distinct material removal mechanisms during rock scratching, ductile and brittle, whose occurrence depends on the magnitude of depth of cut. At shallow depth of cut, ductile-mode cutting dominates and the cutting force is associated with uniaxial compressive strength; at larger depth of cut, brittle failure is dominant and the fracture toughness control the force responses. This study aims at assessing the strength within the ductile-mode cutting and the fracture toughness within brittle failure via rock scratching tests. First, we apply Bažant's Size Effect Law (SEL) to identify the critical ductile-to-brittle transition depth. Then we employ experimental data for ductile mode and brittle mode to determine strength and fracture properties respectively. The good agreement between experimental results and reported values indicates the potential of scratch test as a new technique to characterise rock strength and fracture toughness simultaneously. 1 Introduction The uniaxial compressive strength (UCS) and fracture toughness of rocks are the most common parameters used in civil, mining and petroleum engineering, such as the design of underground structures and stability assessment of rock excavations. The main challenge lies in the fact that conventional measurements of rock strength and fracture properties normally requires intact rock cores of high quality, sophisticated setups or complex sample preparations. In addition, the values determined from experiments are, to some degree, influenced by the size of the specimens. All of these undesirable issues give rise to uncertainty in engineering practice. Recent advances in understanding the mechanism of rock scratch provide an encouraging alternative to the determination of the rock strength and fracture toughness simultaneously. During rock scratching, there is a critical depth dc beyond which rock failure shifts from ductile to brittle regime (Richard et al. 2012 and He et al. 2015). When the depth of cut is small, the rock failure is a strength-driven process with energy dissipated within the failed material in plastic flow (Figure 1a) and the average cutting force is proportional to the depth of cut (see the black solid line in Figure 1c). On the other hand, in deep cutting, in which the rock failure is dominated by the brittle regime with energy dissipated in creating macroscopic discontinuous cracking surfaces ahead of the cutting tool (Figure 1b), the cutting force deviates from the linear proportionality and exhibits a scaling relationship with the square root of the depth of cut (see the red solid curve in Figure 1c), following the theory of linear elastic fracture mechanics (LEFM). Therefore, a critical threshold of depth of cut dc exists that separates the two distinct failure regimes.

ISRM Regional Symposium - EUROCK 2015

ISRM

ISRM-EUROCK-2015-084

Adelaide, Bazant, critical transition depth, equation, experimental data, exploration technology cooperative research centre, fracture toughness, hydraulic fracturing, regime, Reservoir Characterization, reservoir geomechanics, scratch test, Size Effect Law, strength, transition depth, uniaxial compressive strength, Upstream Oil & Gas

Country:

Europe (0.47)
Oceania > Australia (0.30)

Industry: Energy > Oil & Gas > Upstream (0.50)

SPE Disciplines:

Well Drilling (1.00)
Well Completion > Hydraulic Fracturing (1.00)
Reservoir Description and Dynamics > Reservoir Characterization > Reservoir geomechanics (0.91)

Harnessing the Passion - Building Environmental Expertise

Dyer, Emma (Santos)

OnePetroSeptember, 2012

Abstract In the past three years, Santos has undergone substantial growth across multiple jurisdictions. In this time the number of environmental specialists has more than doubled. Santos’ vision is to be a leading energy company for Australia and Asia. To do this we have to have the best people doing the right jobs. To support this, there are a number of approaches and tools that we have developed, including: Development planning systems Mailing lists and group emails The on-line Environment Community The Environment Network meeting Environmental leaders meeting The Environmental Excellence Forum Databases A number of hurdles have been experienced along the path to developing Santos’ environmental professionals into a cohesive knowledgeable cohort. Challenges include: Changing regulatory and community expectations Shortage of appropriately skilled and experienced people Changing technology Busy-ness Changing business needs The fundamental key to succeeding in developing a cohesive environmental community has been using consistent and regular communications. Santos’ journey to build an environmental profession made up of skilled and empowered people that know and support their colleagues is well underway. The challenge is to ensure that we can keep up as technology continues to evolve, community and regulators’ expectations change and the company strives to be a leading energy company for Australia and Asia.

International Conference on Health, Safety and Environment in Oil and Gas Exploration and Production

doi: 10.2118/157490-MS

SPE

SPE-157490-MS

Country:

Oceania > Australia > Queensland (0.47)
Oceania > Australia > South Australia (0.30)

Industry:

Law (1.00)
Energy > Oil & Gas > Upstream (1.00)

Oilfield Places:

Oceania > Australia > South Australia > Cooper Basin (0.99)
Oceania > Australia > Queensland > Surat Basin (0.99)
Oceania > Australia > Queensland > Cooper Basin (0.99)
Oceania > Australia > New South Wales > Surat Basin (0.99)

SPE Disciplines:

Health, Safety, Environment & Sustainability > Environment (1.00)
Health, Safety, Environment & Sustainability > Sustainability/Social Responsibility (0.93)
Management > Professionalism, Training, and Education > Personnel competence (0.46)
Data Science & Engineering Analytics > Information Management and Systems > Artificial intelligence (0.34)

Technology:

Information Technology > Communications > Collaboration (0.46)
Information Technology > Artificial Intelligence > Representation & Reasoning > Planning & Scheduling (0.34)

Hobbs, George (Strategic Chemistry Pty. Ltd.)

Technology Focus: Natural Gas Processing and Handling (April 2012)

OnePetroApril, 2012

Technology Focus In 2010, natural-gas reserves were approximately equivalent to 75% of the oil reserves (including oil sands). Unconventional gas sources continue to make up an increasingly important part of the natural-gas supply, particularly shale gas and coal-bed methane (CBM), which contribute approximately 40% to US natural-gas reserves. Generally, very remote offshore gas reserves cannot be exploited economically by use of fixed subsea pipelines that tend to link the field with a specific geographical market. Operators can maximize market reach through natural-gas liquefaction and improved marine liquefied-natural-gas (LNG) tankers. For ultimate flexibility, four floating LNG-production facilities are predicted to come on stream within this decade. Commercial exploitation of the known massive hydrate reserves probably is some time off; however, the chemistry research involved in hydrate management for current natural-gas production may accelerate progress in that area. Hydraulic-water reuse is key to the future of the CBM and shale-gas industries. There are many opportunities to learn about and share natural-gas technologies. An SPE workshop, “Reducing Environmental Impact of Unconventional Resources Development,” will take place in San Antonio, Texas, 23–25 April 2012. A joint SPE/SEG workshop, “Injection Induced Seismicity,” will be held in Broomfield, Colorado, 12–14 September 2012. There will be an SPE “Tight Gas” workshop in Adelaide, Australia, 10–13 June 2012, and the SPE Unconventional Reservoir Technical Interest Group (TIG) provides a useful information exchange, as does the Gas Technology TIG. The 2013 SPE Unconventional Gas Conference and Exhibition will be held in Muscat, Oman, 28–30 January. The 2013 SPE International Symposium on Oilfield Chemistry to be held in The Woodlands, Texas, 9–13 April, includes topics on gas-processing chemical applications. Acid-gas (CO2 and H2S) removal from natural gas and sequestration/recovery/disposal technologies are very important in exploitation of poorer-quality gas finds. Much work continues in this area, and very large acid-gas-removal units are in operation or are planned for the Arabian Gulf region. Recommended additional reading at OnePetro: www.onepetro.org. IPTC 15208 World’s First Demonstration Project of Natural Gas Hydrate Land Transportation by Tomonori Nogami, Mitsui Engineering and Shipbuilding, et al. IPTC 14206 International LNG Prospects: 2011 and Beyond by Chau Tran, University of Houston, et al. SPE 143019 Underground Natural-Gas Storage in the UK: Business Feasibility Case Study by Esther Escobar, University of Aberdeen, et al.

doi: 10.2118/0412-0108-JPT

SPE

SPE-0412-0108-JPT