Smart technology applications for the optimal management of underground facilities

This study centers on the use of smart technology to improve the lifecycle management of underground facilities.It presents a comprehensive digital solution that addresses the challenges of underground facilities,particularly those related to the extensive use of underground space,as well as the requirements for safety,sustainability,and quality of services.The proposed solution emerged from discussions with experts,companies,and cities involved in the design,construction,and management of underground facilities.In this paper,we first discuss the major challenges of underground facilities,then,we present the development of a smart solution to address these challenges.This study demonstrates a promising perspective for the use of smart technology in the optimal management of underground facilities,and paves the way for its implementation.

Influence of hysteretic stress path behavior on seal integrity during gas storage operation in a depleted reservoir

In this study,we numerically investigate the influence of hysteretic stress path behavior on the seal integrity during underground gas storage operations in a depleted reservoir.Our study area is the Honor Rancho Underground Storage Facility in Los Angeles County(California,USA),which was converted into an underground gas storage facility in 1975 after 20 years of oil and gas production.In our simulations,the geomechanical behavior of the sand reservoir is modeled using two models:(1)a linear elastic model(non-hysteretic stress path)that does not take into consideration irreversible deformation,and(2)a plastic cap mechanical model which considers changes in rock elastic properties due to irreversible deformations caused by plastic reservoir compaction(hysteretic stress path).It shows that the irreversible compaction of the geological layer over geologic time and during the reservoir depletion can have important consequences on stress tensor orientation and magnitude.Ignoring depletion-induced irreversible compaction can lead to an over-estimation of the calculation of the maximum working reservoir pressure.Moreover,this irreversible compaction may bring the nearby faults closer to reactivation.However,regardless of the two models applied,the geomechanical analysis shows that for the estimated stress conditions applied in this study,the Honor Rancho Underground Storage Facility is being safely operated at pressures much below what would be required to compromise the seal integrity.