2. Benchmark solution#

2.1. Calculation method#

The analytical solution is based on the resolution of the two differential equations that govern the deviatory part of the behavior (cf. [R7.01.06] and [R7.01.35]). Choosing the \(\kappa\) parameter to a very large value ensures equivalence between the two models for the load applied.

Deviatory stresses are at the origin of a sliding mechanism (or mechanism of virtual dislocation) of sheets of CSH in nano-porosity. Under deviatoric stress, creep takes place at constant volume. Moreover, creep law UMLV assumes the isotropy of deviatoric creep. Phenomenologically, the sliding mechanism includes a reversible viscoelastic contribution of water strongly adsorbed to the sheets of CSH and an irreversible viscous contribution of free water:

_images/Object_11.svg

eq 2.1-1

The \({j}^{\mathrm{ème}}\) main component of total deviatoric deformation is governed by equations [éq2.1‑2] and [éq 2.1-3]:

_images/Object_12.svg

Eq 2.1-2

where

_images/Object_13.svg

refers to the stiffness associated with the capacity of adsorbed water to transmit charges (load bearing water);

and

_images/Object_14.svg

the viscosity associated with the water adsorbed by the hydrate sheets.

_images/Object_15.svg

Eq 2.1-3

where

_images/Object_16.svg

refers to the viscosity of free water.

In the case of a constraint step

_images/Object_17.svg

, the corresponding deviatoric creep deformation is immediately deduced:

_images/Object_18.svg

Eq 2.1-4

When the elastic part is added, it follows that the total shear deformation is equal to:

_images/Object_19.svg

Eq 2.1-5

_images/10000000000002D00000021CCF95B404C870EAC0.png

2.2. Reference quantities and results#

The test is homogeneous. The deformation is tested at any node.

2.3. Uncertainties about the solution#

Analytical solution.

2.4. Bibliographical references#

The PAPE Y.: UMLV behavioral relationship for the clean creep of concrete,*Code_Aster [R7.01.06] 16 p (2002) Reference Documentation.

  • FOUCAULT, A.: Behavioral Relationship BETON_BURGER, Code-Aster Reference Documentation [R7.01.35], 2011.