Time-Dependent Model for Brittle Rocks Considering the Long-Term Strength Determined from Lab Data

Creep: Time‐dependent brittle deformation in rocks

A micromechanics-based elastoplastic damage model for quasi-brittle rocks

This paper presents a micromechanics-based elastoplastic damage model for quasi-brittle rocks in compression stress state. The plastic strain is considered to be related to frictional sliding along microcracks and inherently coupled with damage evolution. By following a homogenization procedure, we first determine the free energy for the matrix-cracks system. The thermodynamic force associated ...

Brittle creep, damage and time-to-failure in rocks

We propose a numerical model based on static fatigue laws in order to model the time-dependent damage and deformation of rocks under creep. An empirical relation between time-to-failure and applied stress is used to simulate the behavior of each element of our finite element model. We first review available data on creep experiments, in order to study how the material properties and the loading...

Improving the Banks Shareholder Long Term Values by Using Data Envelopment Analysis Model

Given the rapid development of the banking sector, it is reasonable to expect that the performance of banks has become the centre of attention among bank managers, stakeholders, policy makers, and regulators. In order to maximizing the share-holders’ satisfactory level, two bank efficiency measurement approaches, i.e. the production approach and the user cost approach, which are financial evalu...

Prediction of long-term slake durability of clay-bearing rocks

A research program was conducted on different clay-bearing rocks selected from the Ilam, Sarpol-e Zahab and Tajarak regions (Iran) to predict their slaking characteristics. The new durability apparatus (nested mesh drums) separates disintegrated particles varying from > 25.4 to < 2 mm as the drums were rotated. On the basis of the particle size distribution, the disintegration ratio (DR) was us...