THAMES code

The behavior of the buffer material is influenced by the interdependence of thermal, hydraulic and mechanical phenomena. To simulate the water/vapor movement and heat induced water movement, the continuity equation used in the extended THAMES code is as follows ... 

Four research teams—AECB, CLAY, KIPH and LBNL—studied the task with different computational models. The computer codes applied to the task were ROCMAS, FRACON, THAMES and ABAQUS-CLAY. All of them were based on the finite-element method (FEM). Figure 6 presents an overview of the geometry and the boundary conditions of respective models, including the nearfield rock, bentonite buffer, concrete lid, and heater. The LBNL model is the largest and explicitly includes nearby drifts as well as three main fractures... 

This report presents our approach for calculation of the Task. Our numerical code THAMES is the three-dimensional finite element simulator of fully coupled processes. First, we defined the input data for THAMES from the supplied properties of FEBEX bentonite. After calibrations of some parameters such as thermal vapour diffusivity, the analysis that treats fully coupled thermal, hydraulic and mechanical processes was carried out. 

We have developed and improved the numerical code THAMES to predict and assess the coupled THM behaviour in and around the EBS of the geological disposal of high-level radioactive waste. THAMES is a finite element code for analysis of coupled thermal, hydraulic and mechanical behaviour of a saturated-unsaturated medium. Then, we applied THAMES to calculate this task of the DECOVALEX III. In this task, the evolutions and the distributions of stress, relative humidity and temperature at the specified points in bentonite buffer material are required. 

First, we identified the input parameter for THAMES on properties of FEBEX bentonite, because the fundamental properties of FEBEX bentonite had been obtained by various laboratory tests to identify the input data for the numerical code CODE BRIGHT (enresa (1998)). After calibrations of the all required parameters for THAMES, such as thermal vapour flow diffusivity and intrinsic permeability, the coupled THM simulations were carried out. 

The coupled T-H-M numerical code THAMES was applied to simulate the in-situ full scale engineered experiment performed in GTS in Switzerland. 

Sugita Y., Ito A., Chijimatsu M. and Kurikami H. 2002. Prediction analysis A for the PRP with numerical code THAMES, SKB IPR-02-24. 

The equivalent continuum model used for the JNC model is developed by combining the crack tensor theory proposed by Oda (1986) and the constitutive model by Barton et al. (1985). This model simulates the anisotropy of the media by crack tensor theory and the non-linear mechanical and hydraulic behavior by the Barton-Bandis (BB) model. Thus, the properties are changed heterogeneously and anisotropically through the excavation process. The constitutive law is incorporated into the coupled THM code, THAMES (Ohnishi, et al., 1985). 

By using the above non-linear equivalent model, the coupled equations are solved in three dimensions in the coupled THM code THAMES. The continuity equation includes gravity, porosity, the degree of saturation, and the compressibility of water. The equilibrium equations are written as... 

Existing codes of THAMES, Dtransu and PHREEQE are used in the prototype code based on the concept of the Figure 1 and Figure 2. Prototype coupling system has a function of start-up / termination and pause / re-start of each code, and command of get and set for coupling data is described in source program of each analysis code (Figure 3). This prototype code is executed on a SUN ULTRA, Linux and SGI workstation. 

Brick Earih. An impure loamy clay, particularly that of the Pleistocene of the Thames Valley, used for brickmaking. Brick Shapes. See Fig. 1 and the further references in Appendix A. The German didier CO publishes a detailed coding system for refractory bricks and shapes, which is a de facto standard in Europe. Brick Slip. A fired ceramic architectural facing varying from about 13 to 38mm in thickness and produced either as a unit itself or cut from a larger unit. 

---