Mechanical Behavior of Fracture Filled with Variable Medium

2012 ◽  
Vol 472-475 ◽  
pp. 2203-2206
Author(s):  
Jin Gang Chen ◽  
Na Chen ◽  
Jun Li Yang
Keyword(s):  
Mechanical Behavior ◽  
Laboratory Experiments ◽  
Behavior Model ◽  
Flow State ◽  
Linear Elastic ◽  
Ideal Plastic ◽  
Strain Data ◽  
Variable Medium ◽  
Normal Compression ◽  
The Ideal

Filled fracture is a fracture in which sands or other materials occupy some void spaces. This study uses well-controlled laboratory experiments to investigate mechanical behavior of fracture filled with variable medium by means of normal compression and lateral restraint. A large number of stress-strain data are obtained. The mechanical behavior of filled fracture with variable medium can be divided into three phases: rheological phase, compaction phase and linear elastic phase. At the beginning of the experiment, the filled fracture is in the ideal plastic flow state. The overall strength of filled fracture increase with finite deformation and normal stress increasing, and show linear elastic characters. Based on the experiment results and characteristics, the mechanical behavior model of fracture filled with variable medium is constructed, and also its mechanism is analyzed.

Mechanical response of double-stranded DNA to dynamic excitation

2021 ◽  
pp. 107754632110458
Author(s):  
Hamze Mousavi ◽  
Moein Mirzaei ◽  
Samira Jalilvand
Keyword(s):  
Mechanical Behavior ◽  
Mechanical Response ◽  
Actual Condition ◽  
Dimensional System ◽  
One Dimensional ◽  
Linear Elastic ◽  
Dynamic Excitation ◽  
Double Stranded Dna ◽  
Elastic Forces ◽  
Mass Spring

The present work investigates the vibrational properties of a DNA-like structure by means of a harmonic Hamiltonian and the Green’s function formalism. The DNA sequence is considered as a quasi one-dimensional system in which the mass-spring pairs are randomly distributed inside each crystalline unit. The sizes of the units inside the system are increased, in a step-by-step approach, so that the actual condition of the DNA could be modeled more accurately. The linear-elastic forces mimicking the bonds between the pairs are initially considered constant along the entire length of the system. In the next step, these forces are randomly shuffled so as to take into account the inherent randomness of the DNA. The results reveal that increasing the number of mass-spring pairs in the crystalline structure decreases the influence of randomness on the mechanical behavior of the structure. This also holds true for systems with larger crystalline units. The obtained results can be used to investigate the mechanical behavior of similar macro-systems.

Mechanical behavior of poly(methyl methacrylate)-based ionogels

Soft Matter ◽  
2014 ◽  
Vol 10 (40) ◽  
pp. 7993-8000 ◽  
Author(s):  
Mingyu Li ◽  
Jianyu Li ◽  
Hui Na ◽  
Joost J. Vlassak
Keyword(s):  
Methyl Methacrylate ◽  
Mechanical Behavior ◽  
Fracture Energy ◽  
Cross Link ◽  
Poly Methyl Methacrylate ◽  
Link Density ◽  
Cross Link Density ◽  
The Cross ◽  
The Ideal

We demonstrate that the fracture energy of ionogels correlates inversely with the cross-link density. The behavior of ionogels is well captured by the ideal elastomeric gel model.

scholarly journals Energy Dissipation in Solid Roller Bucket and Controlled Stilling Basin for Ogee Stepped Spillway

2019 ◽  
Vol 8 (4) ◽  
pp. 2109-2112
Keyword(s):  
Energy Dissipation ◽  
Laboratory Experiments ◽  
Ideal Condition ◽  
Stepped Spillway ◽  
Type Ii ◽  
Dimensional Parameter ◽  
Stilling Basin ◽  
Sequent Depth ◽  
Tail Water ◽  
The Ideal

Hydraulic jump type II stilling basin is generally preferred as an energy dissipator for ogee spillway but it is uneconomical due to longer structure. On the other hand, roller bucket uses relatively shorter structure over a sloping apron or horizontal stilling basin. In this study, an attempt has been made to evaluate the performance of an ogee profile stepped spillway in combination with solid roller bucket and stilling basin type II for energy dissipation. Laboratory experiments are performed on a physical working model of ogee profile stepped spillway at discharge ranging from 0.0032 to 0.0069 m3 /s for a head of 1.5m, 4m & 7m and the results compared for energy dissipation (non-dimensional parameter (y c / h) = 0.69). The model results show that stepped spillway model without v-notch achieves 92.40 % energy dissipation. Thus this model is found to be more suitable to acquire the ideal condition of sequent depth and tail water depth in stilling basin for all the discharges.

Simulation Analysis of Engine-Oil inside the Clearance between Crankshaft Journal and Bearing Shells in the Ideal Stable Conditions

2014 ◽  
Vol 635-637 ◽  
pp. 532-536
Author(s):  
Pei Shu ◽  
Hong Xin Zhang ◽  
Ru Qin Xiao ◽  
Jin Zhu Shi
Keyword(s):  
Simulation Analysis ◽  
Geometric Model ◽  
Engine Oil ◽  
Flow State ◽  
Engine Operation ◽  
Stable Conditions ◽  
Crankshaft Journal ◽  
Oil Flow ◽  
3D Geometric Model ◽  
The Ideal

For the bush-burning problem in the course of the engine operation. Taking a certain kind of engine as reference, build a 3D geometric model of the engine-oil flow field in the ideal stable conditions with GAMBIT and conduct a simulation of it with FLUENT. It reveals that we can have an intuitive understanding of the flow state and pressure distribution of the engine-oil inside the clearance between the crankshaft main journal and crankshaft bearing as well as the rod journal and rod bearing which provides basis for a further refining of bearing lubrication system, improving the lubrication method and enhancing the efficiency of the lubrication.

scholarly journals Effect of Process Orientation on the Mechanical Behavior and Piezoelectricity of Electroactive Paper

Materials ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 204
Author(s):  
Sean Yoon ◽  
Jung Woong Kim ◽  
Hyun Chan Kim ◽  
Jaehwan Kim
Keyword(s):  
Mechanical Behavior ◽  
Process Orientation ◽  
Linear Elastic ◽  
Strong Shear ◽  
Performance Deterioration ◽  
Alignment Angle ◽  
Anisotropic Elastic ◽  
Stretching Ratio ◽  
Orientation Dependency ◽  
Piezoelectric Charge

This paper reports the effect of process orientation on the mechanical behavior and piezoelectricity of electroactive paper (EAPap) made from natural cotton pulp. EAPap is fabricated by a casting and wet drawing of cellulose film after dissolving cotton with LiCl and DMAc solvent. During the fabrication, permanent wrinkles, a possible factor for performance deterioration, were found in the films. Finite element method was introduced to identify the formation mechanism behind the wrinkles. The simulation results show that the wrinkles were caused by buckling and are inevitable under any conditions. The tensile and piezoelectric tests show that the orientation dependency of the stretched EAPap gives the anisotropic characteristics on both mechanical and piezoelectric properties. In this research, the anisotropic elastic moduli and Poisson’s ratios are reported. The piezoelectric charge constant of EAPap in the linear elastic is calculated. The piezoelectric charge constants of EAPap are associated with the alignment angle in the order of 45° > 0° > 90° due to the strong shear effect. The higher stretching ratio gives the higher piezoelectricity due to the alignment of the molecular chains and the microstructure in EAPap. The highest piezoelectric charge constant is found to be 12 pC/N at a stretching ratio of 1.6 and aligning angle of 45°.

scholarly journals Mechanical behavior of ballasted railway track stabilized with polyurethane: A finite element analysis

2018 ◽  
Vol 251 ◽  
pp. 04056 ◽  
Author(s):  
Zelimkhan Khakiev ◽  
Alexander Kruglikov ◽  
Georgy Lazorenko ◽  
Anton Kasprzhitskii ◽  
Yakov Ermolov ◽  
...  
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Mechanical Behavior ◽  
Finite Element Simulation ◽  
Elasticity Modulus ◽  
Railway Track ◽  
Binding Agent ◽  
Element Analysis ◽  
Linear Elastic ◽  
Element Simulation

Analysis of mechanical behavior of ballast shoulder of railway track reinforced by polyurethane binding agent has been performed by the method of finite-element simulation Limitation of the model of linear-elastic properties of geocomposite has been displayed. Dependence of elasticity modulus of geocomposite on deformation value has been suggested. Influence of penetration depth of polyurethane binding agent on behavior of railway track construction under different train loads has been studied.

scholarly journals ANÁLISE DO COMPORTAMENTO MECÂNICO DE MACIÇOS ROCHOSOS CONTENDO DESCONTINUIDADES ATRAVÉS DO MÉTODO DAS DIFERENÇAS FINITAS VIA IMPLEMENTAÇÃO COMPUTACIONAL [ Analysis of the mechanical behavior of rocky mass with discontinuities through the finite differences method via computational implementation ]

2018 ◽  
Vol 15 (1) ◽  
Author(s):  
Luma Alvarenga Carvalho de Vasconcelos ◽  
Pedro Guilherme Cipriano Silva ◽  
Pedro Ivo Amaro Alves
Keyword(s):  
Rock Mass ◽  
Mechanical Behavior ◽  
Numerical Solutions ◽  
Compressive Force ◽  
Shear Stiffness ◽  
Relative Displacement ◽  
Shear Stresses ◽  
Linear Elastic ◽  
Finite Differences Method ◽  
Fortran 90

RESUMO: Neste trabalho é realizada uma análise computacional por meio da resolução de equações diferenciais para a modelagem de soluções analíticas e numéricas (MDF) do comportamento mecânico de um maciço rochoso contendo descontinuidades. Realizou-se simulações adotando um bloco composto por um material homogêneo, isotrópico e linear elástico sob atuação de uma força externa compressiva aplicada na sua extremidade livre e confinado entre duas descontinuidades rígidas, nas superfícies inferior e superior. A descontinuidade inferior apresenta rugosidade, caracterizada por um módulo de rigidez ao cisalhamento que conduz a uma distribuição de tensão cisalhante e a um deslocamento relativo entre o bloco e a base. Os resultados foram gerados através da compilação dos dados no programa computacional FORTRAN 90, e, com isso, pode-se verificar o deslocamento relativo entre o bloco e a descontinuidade, bem como as tensões atuantes em cada ponto previamente definido; e ainda realizar uma comparação entre as soluções analítica e numérica. Como principal contribuição do trabalho para a área da geotecnia, cita-se a possibilidade de uma análise de deslocamento de descontinuidades presentes em maciços rochosos mais próxima da realidade já que considera o meio como descontínuo. Além disso apresenta-se uma solução computacional de fácil implementação e entendimento.ABSTRACT: In this work a computational analysis is performed by solving differential equations for the modeling of numerical (MDF) and analytical solutions of the mechanical behavior of a rock mass with discontinuities. Simulations were carried out by adopting a block composed of a homogeneous, isotropic and linear elastic material under the action of an external compressive force applied at its free end and confined between two rigid discontinuities on the lower and upper surfaces. The lower discontinuity presents roughness characterized by a shear stiffness modulus leading to a shear stress distribution and a relative displacement between the block and the base. The results were generated through the compilation of the data in the FORTRAN 90 computer program, and with this, it is possible to verify the relative displacement between the block and the discontinuity, as well as the shear stresses acting at each previously defined point; and also perform a comparison between analytical and numerical solutions. The main contribution of the work to the area of geotechnics is the possibility of an analysis of discontinuity displacement present in rock mass closer to reality since it considers the environment as discontinuous. In addition, a computational solution is presented that is easy to implement and understand.

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