Realistic mesh-independent simulations of localization in a macroscopically homogenous material must incorporate (explicitly or statistically) length and orientation scales that reflect microscale inhomogeneities. Weibull statistics (or similar approaches) have long been used to allow for uncertainty in the size and spatial locations of microcracks, but little work has been done to determine th...

The plastic zone of the surrounding rock borehole is a high-quality channel for gas flow. Studying distribution form in boreholes and characteristics extended connection network essential optimal layout drainage boreholes. Considering pressure parameters based on modified Terzaghi effective stress principle Mohr–Coulomb strength criterion. implicit equation boundary derived. influence two-way c...

Abstract Foundation pit excavation through the soft layer has great technical challenges and potential safety risks, especially in soil area. In this study, we use a 3D numerical model of to simulate process. Based on simulation, sensitivity analysis three stiffness parameters ( $${\mathrm{E}}_{\mathrm{ur}}^{\mathrm{ref}}$$ ...

Abstract Wellbore instability problems cause nonproductive time, especially during drilling operations in the shale formations. These include stuck pipe, caving, lost circulation, and tight hole, requiring more time to treat therefore additional costs. The extensive hole collapse problem is considered one of main challenges experienced when Zubair formation. In turn, it caused by increasing wel...

In this paper, a stress integration algorithm is presented for a generalized elasto-plastic material model governed by the three stress invariants I1, J2 and J3. The methodology is successfully applied to the Mohr–Coulomb material model with a non-associated flow rule and implemented in ADINA.