Non-associative elasto-plasticity is the working model of plasticity for soil and rock mechanics. Yet, it is usually viewed as non-variational. In this work, we prove a contrario the existence of a variational evolution for such a model under a natural capping assumption on the hydrostatic stresses and a less natural mollification of the stress admissibility constraint. The obtained elasto-plas...

We give a brief introduction to smoothed particle hydrodynamics methods for continuum mechanics. Specifically, we present our 3D SPH code to simulate and analyze collisions of asteroids consisting of two types of material: basaltic rock and ice. We consider effects like brittle failure, fragmentation, and merging in different impact scenarios. After validating our code against previously publis...

As part of the demonstration of compliance with federal regulations, a shaft seal system has been designed for the Waste Isolation Pilot Plant. The system completely fills the 650-m shafts with components consisting of the common engineering materials, each of which possesses low permeability, longevity, and can be constructed using available technology. Design investigations couple rock mechan...

a Graduate Aeronautical Laboratories and Department of Mechanical and Civil Engineering, Division of Engineering and Applied Sciences, California Institute of Technology, Pasadena, CA 91125, USA b NJU-ECE Institute for Underground Space and Geo-environment, School of Earth Sciences and Engineering, Nanjing University, Nanjing, China, 210093 c Ecole Polytechnique Fédérale de Lausanne (EPFL), Sch...

The self-developed finite element program on return mapping algorithm is used for the simulation of true tunnel with C++ language, while the finite element program is embedded into differential evolution algorithm to incorporate rock mechanics parameters. Applying to Line 1 of Dalian Metro, inversion parameters and true parameters are found to be close, which indicates the superiority and good ...

A MATLAB code for counting the moiré interference fringes recorded by the optical-mechanical crack gauge TM-71 Xavi Marti , Matt D. Rowberry , Jan Blahůt b a Faculty of Mathematics and Physics, Charles University in Prague, Ke Karlovu 3, 12116 Prague 2, Czech Republic b Department of Engineering Geology, Institute of Rock Structure and Mechanics, Academy of Sciences of the Czech Republic, V Hol...

This paper proposes a fractal viscoelastic element via He?s derivative, its properties are analyzed in details by the two-scale transform for first time. The is used to establish Maxwell-rheological model, which unifies creep equation and relaxation equation, includes classic elastic model classical as two special cases. sheds bright light on viscoelasticity, can find wide applications rock mec...

Experiments were performed to determine the extent of penetration of drill water into Grouse Canyon densely welded t ff during use of normal drilling practices. Core samples were examin d from a borehole cored in a rib of the Rock Mechanics drift in G Tunnel at the Nevada Test Site, Nye County, Nevada. Methylene blu dye was added to the drill water to act as a tracer which stained the rock blue...

The mechanisms by which lithology modulates geomorphic processes are poorly known. In the Oregon Coast Range (OCR), rhythmically bedded sandstones of the Eocene Tyee Formation underlie steep, soil-mantled hillslopes, with relatively uniform ridge-valley spacing. These characteristic landforms are perturbed where diagenetic variations manifest as resistant cliffs. Here we use petrology, rock mec...

Characterization of Excavation Damaged Zone (EDZ) around an underground excavation is a major research topic for deep geological disposal of medium to high level radioactive waste. Rock fracturing due to excavation and thermal loading and its resultant rock mass permeability change in the EDZ are important aspects in the EDZ characterisation. A new function to predict rock mass permeability cha...