.... This approach changes the stiffness and strength values of failed intrablock structural elements between pre-peak ("primary"), post-peak ("secondary"), and ultimate ("tertiary") states. The FEM models in the tertiary stage match 96% of overbreak patterns along the case drift, versus 80% in primary stage models...

... Overbreak and tunnel profile quality Most of the authors agree that tunnel boring exca- vation produces less geological overbreak compared to drill and blast (Nord G., 2006; Stewart P. et al., 2006). The overbreak with TBM method is near elim- ination (Tarkoy P.J., 1995). With D&B method should be predicted...

... aware of the consequences of over-excavation, which is likely to occur during the construction of a tunnel due to the degree of uncertainty inherent to rock massifs, is important in order to make the necessary efforts to control this situation. Francis Group variation overbreak consequence...

... conditions. structural geology round length mapping Upstream Oil & Gas correlation Harlem River Reservoir Characterization strength completion newyork city reservoir geomechanics New York City contractor blast tunnel Inwood Marble tunnel overbreak construction geotechnical...

... locally encountered. The encountered ground characteristics, probably governed by the local tectonic and morphological conditions, caused large gravitational overbreaks especially in the front of the production cavern. 1 INTRODUCTION Wafer chip fabrication is a sensitive industrial process constrained...

... limits are called overbreak and underbreak respectively, with the word backbreak used when overbreak is excessive. The more general concept of EDZ (Excavation Damaged Zone) applies to the fractured and fragmented rock volumes that surround a cavity upon blasting, also called DOW (Damage...