**4.2. Thermomechanical-chemical application**

One examines the superposition of actions under static loads featuring constant stress σ in creep conditions of a body lying in a corrosive environment for time *tcs*. The total participation of an action featuring stress σ is calculated with relation (12):

$$P\_T = \left(\frac{\sigma}{\sigma\_{cr}}\right)^{a+1} \text{ \AA} \tag{32}$$

where *δσ* <sup>=</sup>*δYi* =1.

The influence of loading beyond creep temperature and corrosion influence intervene in calculating the total deterioration:

$$D\_T\begin{pmatrix} t \end{pmatrix} = D\begin{pmatrix} t\_c \vdots T\_c \end{pmatrix} + D\begin{pmatrix} t\_{cs} \end{pmatrix} \tag{33}$$

where *D*(*tc*;*Tc*) is the deterioration resulting from loading at temperature (creep temperature) over interval *tc*, and *D*(*tcs*) is the damage caused by corrosive action over interval *tcs* [3, 7].

The critical stress that takes into consideration the deterioration results from the second equation (17), from relations (13) and (32):

$$
\sigma\_{cr}\left(D\right) = \sigma\_{cr} \cdot \left[1 - D\_T\left(t\right) - P\_{res}\right]^{\frac{1}{\alpha + 1}}\tag{34}
$$

where σ*cr* is the critical stress of the undamaged material (*DT* (*t*)=0) and without residual stresses (*Pres* =0).

Other applications of the PCE have been summarized in [1, 2, 12], such as the superposition of mechanical and electrical effects, the superposition of the mechanical loads and magnetic field by shells/buckling, the superposition of effects in thermoelectromagnetism, etc.
