Constitutive model for the low temperature creep of salt (with application to WIPP)

Abstract

While numercus constitutive models have fceer. propose: for the lur*-cr.n' j-^',-.,;creep of salt, this work is the first to develop such a model v.'ir.hir. the-f•-••r-c- .- .-v>. of rate controlling mechanisms and the reformation-mechanism map. L'r.e cf t.hi.frejr.ework permittei unfolding of the rather ccxplicatej low temperature SW, ly-cta:.' creep bel-.nvior ir.t-i liter Siguier responses involving separate refiner •.. i',1: i;. : Lvi : > controlling mechanisms. The observed total creep rate obeys the rul-?. of a;::itivc processes. The creep model incorporates primary (trans i^ni,) creep t=s P. SLT.TO t7>\porameter modification to the steaey-s^a-e creep equation?. Application of the n-.oriel is through a formulation into proper stress an: strtin neasiirps f^r ui:e ir. u Ian?-strain finite element cede. Intensive analysis of available lev; ••.•:- .-:;rerr:f:i-.' ^riaxial creep data produced the appropriate material parameters, including p.^t-ivsti energies and stress dependencies for the separate refines. Material varir-.hions ::rv observed to produce changes in absolute creep rate, without change in controllinrmechanism. Numerous calculations demonstrate the adequacy of the ma:el nr.-i numeric?! nethod to simulate the results of triaxial creep experiments on Souths a st-m llev Mexico salt from the horizons proposed for the Waste-Isolati";-Pilot riant (.V.'TPP). ntSTR' Brrrww nr ™s nnawwt is WAITED

Hydraulic testing around Room Q: Evaluation of the effects of mining on the hydraulic properties of Salado Evaporites

“…Munson et al (1993) also simulated the stresses around Room Q as a function of time. The stress modeling was performed using a finite-element code that implemented the Munson-Dawson model (Munson and Dawson, 1979) to calculate the transient deformation of the evaporites.…”

Geomechanical Model Calibration Using Field Measurements for a Petroleum Reserve

“…The M-D model proposed by Munson and Dawson (1979, 1982, 1984 and extended by Munson et al (1989) has been included in ADAGIO 3 to model the creep behavior of rock salt. Creep is envisioned as arising from the contributions of three appropriate micromechanical mechanisms as determined from salt deformation mechanism map (Munson 1979).…”

“…Creep is envisioned as arising from the contributions of three appropriate micromechanical mechanisms as determined from salt deformation mechanism map (Munson 1979). These mechanisms are (1) a dislocation climb-controlled creep mechanism at high temperatures and low stresses, (2) an empirically specified, but undefined mechanism at low temperatures and low stresses, and (3) a dislocation slip-controlled mechanism at high stresses (Munson et al 1989).…”

Structural evaluation of WIPP disposal room raised to Clay Seam G.

“…A multi-mechanism deformation (M-D) model proposed by Munson and Dawson (1979, 1982, 1984 and extended by Munson et al (1989), has been included in SANTOS to model the creep behavior of rock salt. This model was used for the clean and argillaceous salt.…”