Dynamic to Static Modeling

Geophysics ◽  
2021 ◽  
pp. 1-43
Author(s):  
Javad Sharifi
Keyword(s):  
Reservoir Characterization ◽  
Triaxial Compression ◽  
Rock Physics ◽  
Regression Equations ◽  
Compression Tests ◽  
In Situ Tests ◽  
Factors Affecting ◽  
Static Modulus ◽  
Wide Range ◽  
Static Modeling

Dynamic-to-static modulus conversion has long been recognized as a complicated and challenging task in reservoir characterization and seismic geomechanics, and many single- and two-variable regression equations have been proposed. In practice however, the form and constants of the regression equation are variable from case to case. I introduce a methodology for estimating the static moduli called dynamic-to-static modeling (DTS). The methodology was validated by laboratory tests (ultrasonic and triaxial compression tests) to obtain dynamic and quasi-static bulk and Young’s (elasticity) moduli. Next, rock deformation phenomena were simulated considering different parameters affecting the process. The dynamic behavior was further modeled using rock physics methods. Unlike the conventional dynamic-to-static conversion procedures, the method considers a wide range of factors affecting the relationship between the dynamic and static moduli, including strain amplitude, dispersion, rock failure mechanism, pore shape, crack parameters, poromechanics, and upscaling. A comparison between the data from laboratory and in-situ tests and the estimation results indicated promising findings. The accuracy of the results was assessed by the analysis of variance (ANOVA). In addition to modeling the static moduli, DTS can be used to verify the static and dynamic moduli values with appropriate accuracy when core data is not available.

Integrating Rock Physics, Seismic Reservoir Characterization and Static Modeling of Carbonates; a Case Study from the UAE

2010 ◽  
Author(s):  
Fathy El-Wazeer ◽  
Antonio Vizamora ◽  
Aysha Al Hamedi ◽  
Habeeba Al-Housani ◽  
Peter Abram ◽  
...  
Keyword(s):  
Reservoir Characterization ◽  
Rock Physics ◽  
Seismic Reservoir ◽  
Static Modeling

Bionic Jump Mechanism Analysis Based on Locust Hind

2013 ◽  
Vol 461 ◽  
pp. 184-190
Author(s):  
Dong Hui Chen ◽  
Heng Xie ◽  
Shao Bo Ye ◽  
Ting Wu ◽  
Xin Lu ◽  
...  
Keyword(s):  
Shear Strength ◽  
Triaxial Compression ◽  
Mechanism Analysis ◽  
Compression Tests ◽  
Fibrous Root ◽  
Factors Affecting ◽  
Complex Shear ◽  
Different Types ◽  
Soil Complex ◽  
Triaxial Compression Tests

The structure of corn stubble was complex and closely combined with the soil, so dig location and root-soil separation are the urgent problem of the manufacturing of corn stubble harvesting machinery. This paper mainly focuses on investigating the interaction principles of corn stubble and soil which by the UU triaxial compression tests. Compared the shear strength of three different types of corn root-soil complexes (vertical root, horizontal root, complex root) and pure soil, and analyzed three important factors affecting the root-soil complex shear strength, it was shown that the presence of corn fibrous root can enhance the soil shear strength and different with their layout types. It will provide a theoretical basis for the design of bionic agricultural tillage components for root- soil separation.

scholarly journals Estimation of rock physics properties from seismic attributes — Part 1: Strategy and sensitivity analysis

Geophysics ◽  
2016 ◽  
Vol 81 (3) ◽  
pp. M35-M53 ◽  
Author(s):  
Bastien Dupuy ◽  
Stéphane Garambois ◽  
Jean Virieux
Keyword(s):  
Input Data ◽  
Reservoir Characterization ◽  
Quantitative Estimation ◽  
A Priori ◽  
Rock Physics ◽  
Fluid Phase ◽  
Quality Factors ◽  
Simultaneous Inversion ◽  
Fluid Saturation ◽  
Wide Range

The quantitative estimation of rock physics properties is of great importance in any reservoir characterization. We have studied the sensitivity of such poroelastic rock physics properties to various seismic viscoelastic attributes (velocities, quality factors, and density). Because we considered a generalized dynamic poroelastic model, our analysis was applicable to most kinds of rocks over a wide range of frequencies. The viscoelastic attributes computed by poroelastic forward modeling were used as input to a semiglobal optimization inversion code to estimate poroelastic properties (porosity, solid frame moduli, fluid phase properties, and saturation). The sensitivity studies that we used showed that it was best to consider an inversion system with enough input data to obtain accurate estimates. However, simultaneous inversion for the whole set of poroelastic parameters was problematic due to the large number of parameters and their trade-off. Consequently, we restricted the sensitivity tests to the estimation of specific poroelastic parameters by making appropriate assumptions on the fluid content and/or solid phases. Realistic a priori assumptions were made by using well data or regional geology knowledge. We found that (1) the estimation of frame properties was accurate as long as sufficient input data were available, (2) the estimation of permeability or fluid saturation depended strongly on the use of attenuation data, and (3) the fluid bulk modulus can be accurately inverted, whereas other fluid properties have a low sensitivity. Introducing errors in a priori rock physics properties linearly shifted the estimations, but not dramatically. Finally, an uncertainty analysis on seismic input data determined that, even if the inversion was reliable, the addition of more input data may be required to obtain accurate estimations if input data were erroneous.

An Elastoplastic Model for Granular Materials Exhibiting Particle Crushing

2007 ◽  
Vol 340-341 ◽  
pp. 1273-1278 ◽  
Author(s):  
De An Sun ◽  
Wen Xiong Huang ◽  
Dai Chao Sheng ◽  
Haruyuki Yamamoto
Keyword(s):  
Shear Strength ◽  
Granular Materials ◽  
Triaxial Compression ◽  
Model Performance ◽  
Confining Pressure ◽  
Model Parameters ◽  
Compression Tests ◽  
Particle Crushing ◽  
Wide Range ◽  
Triaxial Compression Tests

A practical elastoplastic constitutive model for granular materials is presented. And the model is suitable for description of the material behaviour for a wide range of stresses, including those sufficient to cause particle crushing. With a limited number of model parameters, the model can predict the confining-pressure dependent stress-strain relation and shear strength of granular materials in three-dimensional stresses, especially of variation of shear strength and dilatancy characteristics due to particle crushing under high confining pressure. The model parameters, which have clear physical meanings, can be determined from the results of isotropic compression test and conventional triaxial compression tests. The model performance is demonstrated for triaxial compression tests of a sand for a wide range of the confining-pressure from 0.2MPa to 8.0MPa.

scholarly journals Geomechanical Upscaling Methods: Comparison and Verification via 3D Printing

Energies ◽  
2019 ◽  
Vol 12 (3) ◽  
pp. 382 ◽  
Author(s):  
Lingyun Kong ◽  
Mehdi Ostadhassan ◽  
Siavash Zamiran ◽  
Bo Liu ◽  
Chunxiao Li ◽  
...  
Keyword(s):  
Multiple Scales ◽  
Triaxial Compression ◽  
Rock Physics ◽  
Petroleum Engineering ◽  
Compression Tests ◽  
Geomechanical Properties ◽  
Rock Fragments ◽  
Rock Types ◽  
3D Printed ◽  
Comparison Of The Results

Understanding geomechanical properties of rocks at multiple scales is critical and relevant in various disciplines including civil, mining, petroleum and geological engineering. Several upscaling frameworks were proposed to model elastic properties of common rock types from micro to macroscale, considering the heterogeneity and anisotropy in the samples. However, direct comparison of the results from different upscaling methods remains limited, which can question their accuracy in laboratory experiments. Extreme heterogeneity of natural rocks that arises from various existing components in them adds complexity to verifying the accuracy of these upscaling methods. Therefore, experimental validation of various upscaling methods is performed by creating simple component materials, which is, in this study, examining the predicted macroscale geomechanical properties of 3D printed rocks. Nanoindentation data were first captured from 3D printed gypsum powder and binder rock fragments followed by, triaxial compression tests on similar cylindrical core plugs to acquire modulus values in micro and macroscale respectively. Mori-Tanaka (MT) scheme, Self-Consistent Scheme (SCS) method and Differential Effective Medium (DEM) theory were used to estimate Young’s modulus in macroscale based on the results of nanoindentation experiments. The comparison demonstrated that M-T and SCS methods would provide us with more comparable results than DEM method. In addition, the potential applications of 3D printed rocks were also discussed regarding rock physics and the geomechanics area in petroleum engineering and geosciences.

scholarly journals Evaluation of Failure Behavior and Strength of Fractured Rock Sample Using In Situ Triaxial Compression Tests and Expanded Distinct Element Method

2010 ◽  
Vol 452-453 ◽  
pp. 225-228
Author(s):  
B. Li ◽  
Y. Jiang
Keyword(s):  
Rock Sample ◽  
Fractured Rock ◽  
Distinct Element ◽  
Triaxial Compression ◽  
Peak Stress ◽  
Failure Behavior ◽  
Compression Tests ◽  
In Situ Tests ◽  
Triaxial Compression Tests

The in-situ tests have been widely used to directly assess the strength and deformability of rock mass, along with which, various numerical approaches were proposed to give rational interpretations to the mechanical phenomenon happening during these tests. In this study, the so-called potential cracks are introduced into DEM model, leading to expanded DEM (EDEM) approach which is capable of simulating the cracking in intact rocks. The EDEM is applied to an in-situ triaixal compression test on a fractured rock sample. The simulation has well represented the failure mode, peak stress and elastic modulus obtained from tests as well as the cracking phenomenon and the slips on fracture planes during the loading process.

Study on Shear Property of Corn Root-Soil Complex

2013 ◽  
Vol 461 ◽  
pp. 430-435
Author(s):  
Dong Hui Chen ◽  
Heng Xie ◽  
Ting Wu ◽  
Ru Jing Pan ◽  
Jin Tong
Keyword(s):  
Shear Strength ◽  
Triaxial Compression ◽  
Compression Tests ◽  
Fibrous Root ◽  
Factors Affecting ◽  
Corn Root ◽  
Shear Property ◽  
Different Types ◽  
Soil Complex ◽  
Triaxial Compression Tests

The structure of corn stubble was complex and closely combined with the soil, so dig location and root-soil separation are the urgent problem of the manufacturing of corn stubble harvesting machinery. This paper mainly focuses on investigating the interaction principles of corn stubble and soil which by the UU triaxial compression tests. Compared the shear strength of three different types of corn root-soil complexes (vertical root, horizontal root, complex root) and pure soil, and analyzed three important factors affecting the root-soil complex shear strength, it was shown that the presence of corn fibrous root can enhance the soil shear strength and different with their layout types. It will provide a theoretical basis for the design of bionic agricultural tillage components for root- soil separation.

Experimental study of a naturally weathered stiff clay

2016 ◽  
Vol 53 (12) ◽  
pp. 2047-2057 ◽  
Author(s):  
Maria Clorinda Mandaglio ◽  
Nicola Moraci ◽  
Marco Rosone ◽  
Camillo Airò Farulla
Keyword(s):  
Shear Strength ◽  
Mechanical Behaviour ◽  
Triaxial Compression ◽  
Experimental Studies ◽  
Water Retention Curve ◽  
Compression Tests ◽  
Weathered Soils ◽  
Wide Range ◽  
Stiff Clay ◽  
Triaxial Compression Tests

Studying the shear strength of a naturally weathered clay is important to understand rain-induced slope failures in weathered soils. However, experimental studies on naturally weathered soils are limited. The paper focuses on the laboratory experimental investigation carried out to analyse the shear strength of a naturally weathered stiff clay that can be found in unsaturated conditions in situ. This has an important practical relevance in the evaluation of the stability conditions of natural slopes at clay outcrops. Different experimental techniques of suction measurement were used to obtain the soil-water retention curve of the clay over a wide range of suctions. Scanning electronic microscope (SEM) observations and results of mercury intrusion porosimetry (MIP) tests are also presented to highlight the considerable fabric arrangement modifications at the microstructural level induced by wetting–drying processes. Moreover, isotropic consolidated drained triaxial compression tests on undisturbed and reconstituted saturated specimens and controlled-suction triaxial compression tests on unsaturated undisturbed specimens were carried out. The test results allowed examination of the saturated mechanical behaviour of clay and comparison of the mechanical behaviour of the saturated material with that in an unsaturated condition.

Factors Affecting Molecular Self-Assembly and Its Mechanism

2012 ◽  
Vol 9 (1) ◽  
pp. 43 ◽  
Author(s):  
Hueyling Tan
Keyword(s):  
Self Assembly ◽  
Building Blocks ◽  
Molecular Engineering ◽  
Molecular Structures ◽  
Polymer Science ◽  
New Approach ◽  
Factors Affecting ◽  
Dna Structures ◽  
Self Assembling ◽  
Wide Range

Molecular self-assembly is ubiquitous in nature and has emerged as a new approach to produce new materials in chemistry, engineering, nanotechnology, polymer science and materials. Molecular self-assembly has been attracting increasing interest from the scientific community in recent years due to its importance in understanding biology and a variety of diseases at the molecular level. In the last few years, considerable advances have been made in the use ofpeptides as building blocks to produce biological materials for wide range of applications, including fabricating novel supra-molecular structures and scaffolding for tissue repair. The study ofbiological self-assembly systems represents a significant advancement in molecular engineering and is a rapidly growing scientific and engineering field that crosses the boundaries ofexisting disciplines. Many self-assembling systems are rangefrom bi- andtri-block copolymers to DNA structures as well as simple and complex proteins andpeptides. The ultimate goal is to harness molecular self-assembly such that design andcontrol ofbottom-up processes is achieved thereby enabling exploitation of structures developed at the meso- and macro-scopic scale for the purposes oflife and non-life science applications. Such aspirations can be achievedthrough understanding thefundamental principles behind the selforganisation and self-synthesis processes exhibited by biological systems.

Studying the factors of regional insurance market development using the correlation and regression analysis

2020 ◽  
Vol 26 (7) ◽  
pp. 1610-1630
Author(s):  
E.L. Prokop'eva
Keyword(s):  
Regression Analysis ◽  
Federal District ◽  
Insurance Market ◽  
Market Development ◽  
Insurance Markets ◽  
Regression Equations ◽  
Factors Affecting ◽  
Correlation And Regression Analysis ◽  
Country Level ◽  
Inverse Effect

Subject. The article investigates and quantifies factors of insurance markets functioning in Russian regions, and reveals possibilities to manage them. Objectives. The purpose of the study is to substantiate regional factors that determine the specifics of regional insurance market development; to quantify them to increase the efficiency of regional insurance. Methods. The study draws on statistical methods, functional analysis, algorithm development, correlation and regression analysis. Results. I calculated coefficients of pair and multiple correlation with the indicators of insurance markets in the context of the subjects of the Russian Federation, and composed regression equations. Based on the analysis, I determined the algorithm for inverse effect of the insurance market on the economic, social, fiscal and environmental performance of the region, offered appropriate measures aimed at developing the economic potential of the region and its social sphere. Conclusions. The paper considers the case of the Republic of Khakassia, one of depressed subjects in the Siberian Federal District. The developed models can be used for other regions of Russia, given the geographical and economic features of development. The findings may help generate regional strategies for socio-economic development at the country level. The scientific contribution and the novelty of the work consist of systematizing and quantifying the factors affecting the insurance mechanisms of regional markets, and assessing the inverse effect of insurance mechanisms on integrated development of the region.

Sign in / Sign up

Export Citation Format

Share Document