Mesh sensitivity in discrete element simulation of flexible protection structures

The Discrete Element Method (DEM) has been employed in recent years to simulate flexible protection structures undergoing dynamic loading due to its inherent aptitude for dealing with inertial effects and large deformations. The individual structural elements are discretized with an arbitrary number of discrete elements, connected by spring-like remote interactions. In this work, we implement this approach using the parallel bond contact model and compare the numerical results at different discretization intervals with the analytical solutions of classical beam theory. Successively, we use the same model to simulate the punching test of a steel wire mesh and quantify the influence of a different number of elements on the macroscopic response

Non-invasive portable geophysical tool to monitor water content in earthen long linear infrastructures

The use of electrical conductivity measurements from a non-invasive hand held electromagnetic probe is showcased to monitor the water content of earthen embankments at routine inspections. A methodology to convert the electrical conductivity measurements from the electromagnetic device into water content values is illustrated. The methodology is based on measuring the soil electrical conductivity variation with respect to a baseline reference condition and calibrating a water content - electrical conductivity relationship by comparing electrical conductivity readings from the electromagnetic probes with water content readings taken from geotechnical probes installed in a few sections of the embankment. The values of water content converted from the conductivity measurements according to the proposed procedure were found to be in very good agreement with independent measures of water content taken at times well beyond the calibration period

The Impact of a Permeation Grouting Technique Quantitatively Assessed through a Process-Focused Life Cycle Assessment

Permeation grouting technique can be considered nowadays a well-established ground improvement strategy in urban built environments, where an accurate fine-tuning of its component can lead to tailored and efficient interventions. But how environmentally impacting is it? Using life cycle assessment analyses (LCA) and focusing on the construction phase, this research highlights the leverages that can improve the environmental performance of this geotechnical construction process. The alternative approaches in terms of materials and processes are identified, quantified and compared using the standard output of the LCA analysis and represent the ideal input for the three-step sustainability assessment method for geotechnical infrastructure developed by the author

Novel approach for health monitoring of earthen embankments

This paper introduces a novel modular approach for the monitoring of desiccation-induced deterioration in earthen embankments (levees), which are typically used as flood-defense structures. The approach is based on the use of a combination of geotechnical and noninvasive geophysical probes for the continuous monitoring of the water content in the ground. The level of accuracy of the monitoring is adaptable to the available financial resources. The proposed methodology was used and validated on a recently built, 2-km-long river embankment in Galston (Scotland, United Kingdom). A suite of geotechnical probes was installed to monitor the seasonal variation of water content over a 2-year period. Most devices were calibrated in situ. A novel procedure to extrapolate the value of water content from the geotechnical and geophysical probes at any point of the embankment is shown. Desiccation fissuring degrades the resistance of embankments against several failure mechanisms. An index of susceptibility is proposed here. The index is a useful tool to assess the health state of the structure and prioritize remedial interventions

Novel approach for health monitoring of earthen embankments

This paper introduces a novel modular approach for the monitoring of desiccation-induced deterioration in earthen embankments (levees), which are typically used as flood-defense structures. The approach is based on the use of a combination of geotechnical and noninvasive geophysical probes for the continuous monitoring of the water content in the ground. The level of accuracy of the monitoring is adaptable to the available financial resources. The proposed methodology was used and validated on a recently built, 2-km-long river embankment in Galston (Scotland, U.K.). A suite of geotechnical probes was installed to monitor the seasonal variation of water content over a 2-year period. Most devices were calibrated in situ. A novel procedure to extrapolate the value of water content from the geotechnical and geophysical probes at any point of the embankment is shown. Desiccation fissuring degrades the resistance of embankments against several failure mechanisms. An index of susceptibility is proposed here. The index is a useful tool to assess the health state of the structure and prioritize remedial intervention

A Sustainability-based Approach for Geotechnical Infrastructure

Urban growth needs large cities, and the current emphasis on landscape preservation makes using underground spaces both an opportunity and a significant necessity. However, underground construction techniques significantly impact the sustainability of the built environment, including infrastructure systems and their entire supply chains. Nowadays, there is a shortage of quantitative methodologies to assess and measure the sustainability of underground building processes that effectively integrate the three pillars of sustainability (environmental, social, and economic). Thus, this study aims to solve the abovementioned issues by explaining how to incorporate sustainability goals into geotechnical projects to address measure-driven strategies and eco-design-based solutions appropriately. This study illustrates a novel methodology based on the Life Cycle Thinking approach, with a particular emphasis on geotechnical ground improvement techniques. Specifically, the suggested method incorporates the concept of the EU Taxonomy, following the EU Green Deal, with the Envision framework to guide decision-makers toward a more sustainable, resilient, and equitable infrastructure design. In addition, incorporating a cradleto-grave Life Cycle Assessment (LCA) into the suggested methodological approach will improve the quantitative estimation of the performance of construction processes. The definition of the proposed method will provide the guidelines to systematically assess the sustainability of geotechnical infrastructures to allow further the selection of an optimal solution to reduce their impact from an environmental, social, and economic point of view