|
|
Cardu, M., & Seccatore, J. (2016). Quantifying the difficulty of tunnelling by drilling and blasting. Tunn. Undergr. Space Technol., 60, 178–182.
Abstract: This study deals with industrial trends in tunnelling by drill and blast (D&B). We perform a statistical analysis of accumulated experience from the 1950s to the modern day to provide advice for proper project management in tunnel driving. The basis of the study is a wide database of tunnel blast schemes. This database is made of excavation parameters, and considers two main families of blasts: with parallel hole cuts and with inclined hole cuts. Such parameters are analysed by means of statistical regression. Correlations are shown. We present a general curve of correlation between tunnel sections and specific drilling and specific explosive consumption. We show how pull efficiency cannot be correlated to a single parameter, and how tunnelling by D&B needs to be treated as a complex system. Finally, we propose a method for quantifying and classifying the difficulty of tunnelling. The deviation of specific drilling (SD) from industrial average trend is used as an indicator of difficulty: easier when SD is lower than average, and more difficult when SD is higher than average. We show how such deviation can be preliminarily associated with lithotypes. This provides to designers and cost estimators a tool of a first approximation for D&B cost prediction at the pre-feasability and feasibility stages of a tunnelling project. (C) 2016 Elsevier Ltd. All rights reserved.
|
|
|
|
Cardu, M., Godio, A., Oggeri, C., & Seccatore, J. (2022). The influence of rock mass fracturing on splitting and contour blasts. Geomech. Geoengin., 17(3), 822–833.
Abstract: Splitting and contour blasting are aimed to achieve suitable profiles by cutting along a surface, while common blasting is intended to detach and to fragment relevant rock volumes by increasing the fracturing state. These techniques are adopted in both underground works (tunnels, caverns, quarries) and also for surface excavations (quarries, mines, rock slopes engineering). Contour blasts are widely used techniques in mining and civil engineering to enhance performance while maintaining the safety of personnel and infrastructure. Splitting blasts are mainly used in dimension stone mining to obtain intact blocks of valuable ornamental stone. The parameters of controlled blasting (geometry, charge, blast agent) require an accurate selection using optimised blasting patterns and explosive properties; most of the proposed methods are limited and unsatisfactory due to insufficient consideration of rock mass properties. A quick but effective comparison and analysis of the different characteristics of the rock mass and its heterogeneities is presented, as it indicates a better strategy to determine a tailored blasting design for a given site, thus significantly improving the contour blasting quality.
|
|
|
|
Di Lorenzo, A., Pasqua, A., Cardu, M., Godio, A., & Seccatore, J. (2019). Simplified methods of geomechanical analysis for small-scale underground mining. In 14th International Congress on Rock Mechanics and Rock Engineering.
|
|
|
|
Dragano, M. A., Seccatore, J., Cardu, M., Marin, T., & Bettencourt, J. (2019). Influence of blasting charges and delays on the energy consumption of mechanical crushing. REM, 72(2).
|
|
