Book: Rock Engineering for Concrete Dam Foundations

1 Principle of overcoring Overcoring estimates in-situ stress by measuring the strain or deformation recovered when a volume of rock is isolated from the surrounding stress field. A pilot hole is drilled from the end of a larger borehole, an instrumented cell is installed in it, and the rock around the cell is then cut free with a larger concentric core barrel (Figure 1). As the annulus advances past the cell, the rock core unloads and the instrument records the elastic resp

The TBM Face Support Pressure Assessment Tool is an advanced web-based engineering application developed to evaluate tunnel face stability and determine the required support pressure for Earth Pressure Balance (EPB) and Slurry Shield Tunnel Boring Machines (TBMs). The tool integrates several internationally recognised analytical approaches and provides engineers with a transparent framework for assessing face stability, groundwater control, blow-out risk, and geotechnical unc