Enrique Romero is Full Professor and Head of the Geotechnical Laboratory at the Universitat Politècnica de Catalunya (Spain) and Full Research Professor in the Geomechanics Group at CIMNE (Spain).
His research mainly focuses on theoretical and experimental studies of multi-physics and multi-scale processes of geomaterials. He is the author of 350+ scientific papers (51 journal papers dealing with experimental soil mechanics with more than ten citations in Scopus), a member of editorial boards of several international journals, and co-editor of the books ‘Advanced Experimental Unsaturated Soil Mechanics’ (2005) and ‘Laboratory and Field Testing of Unsaturated Soils’ (2009).
Among recent awards, he has been ‘2nd European Distinguished Lecturer on Unsaturated Soils’ (2020). He co-chaired the ‘4th European Conference on Unsaturated Soils’ held in Lisbon in 2020 and co-authored the ‘State-of-the-art paper on Unsaturated Soils’ at ICSMGE 2022 in Sydney. He has been elected (January 2022) as chair of TC 106 ISSMGE of Unsaturated Soils.

Themed Lecture

New challenges in experimental unsaturated soil mechanics

Advanced experimental tools to approach phenomena at different scales for observing and interpreting multiphase (liquid, gas and solid) motion in porous materials and physical mock-ups to support and mimic field tests are required to expand our capability to predict the response of unsaturated porous media in real-life engineering applications and emerging technologies. Experimental techniques should not be merely understood as standard tools for model validation, and parameter estimation in model calibration runs. Experimental tools should also help better understand processes (permeation grouting, generation of gas pathways, interfaces in rooted soils, … ), assist in the characterisation of smaller structural levels (micro/macro interactions and evolution, pore connectivity, local heterogeneity in density, …) and the composition of materials (binary mixtures, rooted soils, grouted soils, …). In addition, theoretical and/or numerical models must accompany the interpretation of multi-physics experiments to exploit better the information provided by measurements (boundary value problem compared to point test), to strengthen confidence in the experimental results (validation of the experimental techniques) and to support scoping calculations to guide mock-up design and experimental protocols.
The presentation will focus on recent tests at the Geotechnical Laboratory UPC, in which different phenomena dealing with unsaturated soils have been approached at varying scales of observation (starting from pore/grain level, point tests, and mock-up experiments to progressively upscale to applications). Two cases related to the storage with engineered barriers of highly pollutant waste from the energy sector will be discussed. Different experimental techniques are used, from X-ray computed tomography to highly instrumented mock-ups mimicking in-situ tests and real applications. One application will use a granular bentonite-based mixture for vertical sealing systems for deep waste disposal. The other will mimic an in-situ demonstration test of gas permeable seals on compacted sand-bentonite mixture currently running at Grimsel Test Site (Switzerland). In the latter case, a major experimental challenge was to design a mock-up that would allow the mixture to be compacted in several layers, the controlled application of normal stress, and perform gas injection tests with flow parallel to compaction lifts.