The integration of Rock Engineering in European Geotechnical Standards is one of the great achievements of the future Eurocode 7: 202x (EC7). The design of a geotechnical structure, according to prEN1997:202x [1], comprises five major tasks:1. Reliability management: a series of classifications that combine to place the geotechnical structure into a single Geotechnical Category. 2. Ground investigation: whose main outputs are a representation of the ground and groundwater at the site, known as the “Ground Model”, and the results of field and laboratory tests relative to different ground properties and test parameters. 3. Design verification: covering all the procedures to verify that no limit states are exceeded in any design situations that the structure encounters during its service life. 4. Design implementation: in which the structure is constructed while meeting the design assumptions and other detailed plans developed during the design phase. 5. Reporting: all work carried out during the design and execution of the geotechnical structure must be documented by carrying out the following reports: Geotechnical Investigation Report (GIR), Geotechnical Design Report (GDR) and Geotechnical Construction Record (GCR). The paper shows the different tasks that the designers must perform to verify the stability of a rock excavation: reliability management, ground investigation and design verification. During this process, the various new concepts that appear in the future EC7 (Geotechnical Category, Ground Model, Representative values, Design Situations and Design Cases) were applied. The results obtained show that the problem of a rock slope stability can be successfully solved in the frame of the Partial Factor Method, developed in the future EC7. The case under study is a rock slope produced by an excavation of an open pit next to an existing building. The excavation depth is 15 m (5 m in soil material and 10 m in rock material) with an angle of slope of 90º, as can be seen in Figure 2-left. This case was proposed by Guido Nuijten as part of the works performed by the final project team of the future Eurocode (CEN TC250-SC7-PT6).

The conventional design approach of any type of passive protection work aiming at reducing the risk associated with rockfall is energy-based: the total kinetic energy of the falling block in a given position of its trajectory (action, in Limit State Design (LSD) terminology) must be compared to the maximum energy absorption capacity of the protection work (resistance, in LSD terminology). The LSD approach, implemented in Eurocode 7 (EC7), shows some limitations in the case of unconventional geotechnical problems such as rockfall phenomena, since the main parameters of these systems are not considered. To overcome these limitations, one proposed solution is the application of Reliability Based Design (RBD) approaches through the definition of a reliability index, a useful and complementary tool to provide geotechnical structures with a uniform probability of failure. The RBD approach deals with the relationship between the loads that a system must support and the system's ability to support those loads. The RBD therefore shifts the analysis towards a fully probabilistic one, in which each parameter is considered a variable expressed by a known Probability Density Function (PDF). In this work, particular attention has been given to innovative rockfall protection structures such as hybrid barriers and/or attenuators: they do not stop the block by capturing and retaining it in a deformable net, but by dissipating its kinetic energy (up to 0 for hybrid barrier) and forcing it along a trajectory close to the ground or guiding it towards a collecting area. Therefore, in ideal conditions, the block does not stop within the net itself. Considering the applicability of RDB approach, the paper focuses on the response of these structures to the impact of the block and their absorption capacity at different stress levels. The rockfall barriers are made up of a series of structural elements (cables, interception panels, pots, anchoring system, …) which contribute together with the absorption of the impact energy. In this context, numerical modelling represents a powerful solution to reproduce the behaviour of these structures subjected to dynamic impacts at different Kinetic Energy levels. With this purpose 3D numerical simulations by FEM software ABAQUS were carried out, starting with simplified models to identify which parameters most affect the system response. In addition, different structural element components were analysed to reproduce their behaviour both in static and dynamic conditions to test their absorption capacity useful for the RBD approach.

Rock engineering projects that implement the observational method often use a ‘traffic light’ scheme to indicate the system’s status. Such schemes are convenient in practice, but subjective and ambiguous definitions of performance associated with each colour in the scheme and lack of clarity of risks are drawbacks. We tackle these deficiencies by proposing a probabilistic traffic light system with an extended colour range. Simulations using the convergence-confinement model (CCM) for a circular tunnel are presented to demonstrate the system. The geometry and colours of the bivariate cumulative probability distribution provide essential information regarding the system’s behaviour. We conclude that a probabilistic traffic light system can help assess the performance of rock engineering projects being designed and constructed using the OM in accordance with Eurocode 7.

For improving the quality and reliability of geotechnical investigations process, the concept of 'influence region' has been recently proposed. The concept of influence region is an attempt to move from 'experience-based' geotechnical investigations to a 'mathematical equation-based estimation and understanding' of ground investigations. It’s an attempt to improve quality of existing geotechnical process and to make it more reliable. Although the newly proposed concept of influence region is based on author's field experience and conceptualized while working in real life projects, its theory still needs to be tested and validated. Considering need of testing and validation of this new concept of 'influence region', and proving it's theory, in this paper we are proposing different methodologies for field and laboratory tests. The paper will cover geotechnical investigations in different ground conditions i.e., soft-medium-hard conditions for both soil as well as for rock and will propose testing methodologies for both laboratory and field testing. The proposed methodologies will consider geo-mechanics, hydraulics, deformation parameters for soil and rock for testing the concept of influence region. To explain practical application of the concept we will be estimating influence region of RQD* (*Rock Quality Designation) parameter. RQD is most commonly used parameter for accessing the quality of rock. RQD is one such parameter which is applied in almost all empirical formula for accessing quality of rocks. The expected outcome of this paper is to have testing and validation methods for both lab as well as for field testing for proving the concept of 'influence region' of geotechnical investigation points, sampling zone. Also, to show the practical application of the concept, an example of RQD influence region estimation and its equation is presented. Author's view is as influence region concept is an equation-based understanding of geotechnical ground investigations, it has potential to be included in Eurocode/ ISO standards. By providing testing, validation methodologies and showing practical application of the influence region concept, this paper will serve as a scientific tool to geotechnical engineers.