1. Reinvestigation into Closure Predictions of Room D at
the Waste Isolation Pilot Plant
Benjamin Reedlunn, Ph.D.
7th US/German Workshop on
Salt Repository Research, Design and Operation
Washington, DC
September 7-9, 2016
Abstract
Room D was an in situ, isothermal, underground experiment conducted at the Waste
Isolation Pilot Plant between 1984 and 1991. The room was carefully and redundantly
instrumented to measure horizontal and vertical closure immediately upon excavation and
for several years thereafter. Early finite-element simulations of salt creep around Room D
under predicted vertical closure by 4.5×, causing investigators to explore a series of
changes to the way Room D was modeled. Discrepancies between simulations and
measurements were resolved through a series of adjustments to model parameters, which
were openly acknowledged in published reports.
Interest in Room D has been rekindled recently by the U.S./German Joint Project III and
Project WEIMOS, which seek to improve predictions of rock salt constitutive models.
Joint Project participants calibrate their models solely against laboratory tests, and
benchmark the models against underground experiments, such as room D. This
presentation describes updating legacy Room D simulations to today’s computational
standards by rectifying several numerical issues. Subsequently, the constitutive model
used in previous modeling is recalibrated against a suite of new laboratory creep
experiments on salt extracted from the repository horizon of the Waste Isolation Pilot
Plant. Simulations with the new, laboratory-based calibration under predict Room D
vertical closure by 3.1×. A list of potential improvements is discussed.
Sandia National Laboratories is a multi-mission laboratoryoperated by Sandia Corporation,a wholly owned
subsidiaryof Lockheed Martin Corporation,for the U.S. Departmentof Energy's National Nuclear Security
Administration under contractDEAC04-94AL85000.SAND2016-8559 A.
