In this interview with Lia Peña, Head of Geomechanics at Anddes Peru, we explore the importance of the geological base and its fundamental role in geotechnical-geomechanical characterization. Lia explains how, throughout her career in various geotechnical and geomechanical projects, the proper characterization of materials has become increasingly relevant, whether in slope stability or in the foundation of structures.
An interview with Lía Peña
Could you share experiences about your participation in projects?
As a geological engineer, I always seek to identify and understand any geological aspect that may influence a project. At the beginning of my career, I focused my attention on the behavior of Quaternary deposits, which, although of the same type, may be made up of layers with very different characteristics. The same occurs with the rock basement, where the degree of weathering or the type of hydrothermal alteration can significantly influence its geotechnical response. All these factors allow for a more precise and useful characterization for the engineering of the project.
How has your experience impacted the success of a project?
I had the opportunity to participate in the design of a large waste dump, whose foundation was located on an alluvial deposit. Initially, the background information indicated that the conditions were favorable, as gravel and sand predominated. However, upon further study, we identified the presence of thick layers of clays and silts, which posed a risk to the stability of the structure.
Thanks to this finding, we proposed expanding the subsurface investigation to obtain a better spatial perspective of these fine materials and, with it, develop an appropriate engineering solution that would guarantee the stability of the deposit.
How does a detailed characterization of the bedrock contribute to the project’s safety?
Just as a possible failure could be foreseen in the previous case due to the presence of an unidentified clay layer, the bedrock also requires an exhaustive analysis. Its physical behavior varies considerably depending on the type and degree of hydrothermal alteration to which it has been exposed.
For example, a silicified bedrock is usually more resistant and favorable for foundation. On the other hand, when it presents advanced or intermediate argillic alterations, its resistance can be drastically reduced, which compromises the stability of the project.
What tools or guidelines are used to adequately assess the bedrock?
There are various references in the field, such as technical articles, guides, and national and international regulations, that establish differentiated treatments for the different types of altered bedrock. These guidelines, based on their physical properties, are key to geotechnical stability analyses and allow defining the most appropriate design criteria for each case.
What is the impact of an adequate geotechnical-geomechanical characterization on the safety of a project?
In terms of safety, a precise geotechnical characterization significantly reduces the probability of failures, ensuring the continuity of the operation and, above all, protecting the integrity of human resources. The correct identification and analysis of materials allows for the design of safer and more sustainable structures, minimizing risks and optimizing project efficiency.