## 1 Introduction  
The percussive drilling process is commonly used in tunnelling and mining activities. The impact of a piston on the drill rod creates a stress wave that is transferred into the rock through the tool buttons. The rock is then fragmented and flushed out by using water or air. Unlike the situation at quasi-static indentation, the percussive drilling corresponds to a transient dynamic problem involving local high strain-rate tensile and confined compression loadings within the rock. This is the reason why the mechanical behaviour of Linguild Sandstone needs to be investigated using dynamic experimental methods aimed at numerically simulating the behaviour of the rock under the loading induced by a percussive drilling process. In the present study, contrary to the situation in a parallel study (static experiments) [1], bending tests, and uniaxial compression tests have not been considered under dynamic loading. Indeed, in the bending tests certain loading-rate inertial effects are acting under dynamic loading. This leads to a potential overestimation of the bending strength deduced from the measured input force without specific data processing that takes into account the non-equilibrium state of the sample [2]. In uniaxial compression tests, due to the high sensitivity of geomaterial strength compared to the applied confinement, inertial effects acting at high-rates may induce an artificial that provides an apparent increase of uniaxial compression strength [3]. On the other hand, quasi-oedometric compression tests are preferred under dynamic conditions. However, as illustrated in the previously mentioned parallel study [1], such experiments need a very large capacity servo-hydraulic press (1 MN capacity) or a large diameter SHPB (Split-Hopkinson Pressure Bar) apparatus. For instance, in previous dynamic QOC tests [4], the input and output Hopkinson bars were 80 mm in diameter and made of high-strength steel. This provides an impact loading (\(F_{input}=\frac{1}{2}\rho C_{0}A_{0}V_{impact}\)) of about 1.6 MN (with a striking velocity of 16 m/s), which made it possible to achieve an axial load about 1 MN within the sample and the output bar. Unfortunately, this apparatus was unavailable in the present study. On the other hand, previous experiments performed on dry siliceous aggregate concrete (without effect of free-water pressure) [5] and on high-strength concrete [6] showed a limited increase of strength when the static and dynamic testing results were compared. The above results are the reason why, in dynamic conditions, the bending technique and both quasi-oedometric and uniaxial compression testing methods were discarded in favour of other techniques, namely the spalling and the edge-on impact techniques, in an open and sarcophagus configuration. In [7], it is claimed that, rather than applying the same \"static techniques\" in \"dynamic conditions\", it is better to consider specific experimental methods in view of investigating and modelling the damage processes involved in geomaterials at high rates. To do so, a classification into four types of experimental methods was proposed [7]. This is done by separating the experimental methods for an analysis of damage processes via time-resolved observations (ultra-high-speed imaging, full field measurements); from those for post-mortem analysis at a microscopic scale (measurements of crack densities, micro-tomography analysis); from the experimental methods for parameter adjustment (flaw distribution, crack speed); and from those for numerical validation at a macroscopic scale (velocity profile measured on a free surface). In the present study, two experimental methods were considered. The spalling technique is used to characterize the mechanical behaviour of Linguild Sandstone under dynamic tensile loading. This technique relies on the measurement of particle velocity of the free face of a cylindrical sample thanks to a laser interferometer.