ên13th International Conferenceon Fracture June 16–21, 2013,Beijing, China -3- the test piece not further ruptures by fatigue; Life fatigue (Nf), or the number of cycles that rupture occurs in the body of the test piece for a particular alternated stress level (S) above (σRf). After sizing the body-of-evidence, the realization of the mortar compression fatigue test is next. The tests were performed on a universal testing machine MTS 810, being made via control force which results in constant amplitude alternating stress across the tests. The body of the test piece was cast in a mold iron, running in three layers of 4 cm each, and applying 25 blows on each layer. The procedure for determining the body-of-evidence to the MTS 810 was given as follows: initially, for the specimen used in the compression test, we used two circular steel plates holding the specimen fixed. As can be seen in Figure 2a and Figure 2b. (a) (b) Figure 2– (a) - (b)Endurance test compression. 4. Thermal Analysis The purpose of the thermal analysis was to determine how the temperature distribution behaves inside the wall, and therefore inside coating structure, after the incidence of atmospheric thermal shock abroad. The first mathematical simplification was made to adopt an equivalent wall composed of only one material, which replaces the conventional wall, composed of five layers of materials. Thus it was possible to work with only one equivalentthermal diffusivity parameter( ߙ ). The temperature distribution analyticalequationܷ ሺ ݐ ,ݕ ሻvaries in function of the wall thickness (direction ݕ ) and time ( ݐ ).It was obtained from the problem depicted in partial differential equation of heat diffusion: ߙ డమడ௬ మ ൌడ డ ௧ (3) The boundary conditions of the problem, then, represent the heat exchanges by conduction and convectionat the faces facing the interior and exterior of the building: െ ܭ డడሺ௬ௗ,௧ሻ ൌ݄ ൫ܷ ሺ݀ , ݐ ሻെܷ ஶሺ ݐ ሻ൯െ ܫߛ ሺ ݐ ሻ (4) െ ܭ డడሺ௬,௧ሻ ൌ݄ ൫ܷ െܷ ሺ0, ݐ ሻ൯ (5) Whereܷ ஶሺ ݐ ሻis the air temperature outside the building, and ܫ ሺ ݐ ሻrepresents the supply of thermal energy from the sun to the facade over time, modeling it as a source of heat within the system. Having in mind that τ is the time instant at which occurs the heat shock, these features were modeled as it follows:
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