Showing papers by "Herbert H. Einstein published in 2023"
TL;DR: In this article , a discrete event simulation-based model has been proposed to estimate tunnel utilization with different levels of accuracy, which is a promising utilization estimation as it incorporates the uncertainties in various tunneling activities in the determination of the delays during the tunneling and in the estimation of machine utilization.
01 Feb 2023
TL;DR: In this paper , a decision-making cycle of the sort illustrated in Figure 1 is proposed to balance cost and safety in rock engineering and engineering geology, for instance, in dam safety, underground construction, mining, and nuclear waste management.
Abstract: A decades-long effort by many contributors to bring rational decision making to rock engineering and engineering geology — for instance, in dam safety, underground construction, mining, and nuclear waste management — has led to an increasingly unified approach in practice. The addition of observational techniques quantified through Bayesian thinking leads to adaptive designs characterized in a decision-making cycle of the sort illustrated in Figure 1. This way of thinking fosters a balancing of cost and safety.
TL;DR: In this paper , a pressure-controlled Hele-Shaw cell was used to investigate different physical processes in rough fractures using 3D-printed rock analogs, which can measure high-resolution fracture aperture and tracer concentration maps under relevant field stress conditions.
Abstract: In this paper we present a novel pressure-controlled Hele-Shaw cell to investigate different physical processes in rough fractures using 3D-printed rock analogs. Our system can measure high-resolution fracture aperture and tracer concentration maps under relevant field stress conditions. Using a series of hydraulic and visual measurements, combined with numerical simulations, we investigate the evolving fracture geometry characteristics, pressure-dependent hydraulic transmissivity, flow channeling, and the nature of mass transport as a function of normal stress. Our experimental results show that as the fracture closes and deforms under increasing normal loading: (1) the contact areas grow in number and size; (2) the flow paths become more focused and tortuous; and (3) the transport dynamics of conservative tracers evolve towards a higher dispersive regime. Moreover, under the applied experimental conditions, we observed excellent agreement between the simulated- and the experimentally measured- hydraulic behavior. This article is protected by copyright. All rights reserved.