12.5.3 Equivalent Age

You may invoke equivalent age calculation for a material via the EQUAGE input item. This input also indicates the method to be applied.

    (syntax)

ARRTYP

applies a calculation method according to an Arrhenius-type equation [§12.5.3.1].

SAUL

applies a calculation method according to the definition by Saul [§12.5.3.2].

parameters

are specific input for the applied method as described in the referred sections.

12.5.3.1 Arrhenius-type Equation

A well-known Arrhenius-type equation for the equivalent age is

$$\int_{{0}}^{{t}} \left(\vphantom{ c_{\mathrm{A}} \left( \frac{ 1 }{ T_{\mathrm{ref}} } - \frac{ 1 }{ T ( \tau ) } \right) }\right. \left(\vphantom{ \frac{ 1 }{ T_{\mathrm{ref}} } - \frac{ 1 }{ T ( \tau ) } }\right. {\frac{{ 1 }}{{ T_{\mathrm{ref}} }}} {\frac{{ 1 }}{{ T ( \tau ) }}} \left.\vphantom{ \frac{ 1 }{ T_{\mathrm{ref}} } - \frac{ 1 }{ T ( \tau ) } }\right) \left.\vphantom{ c_{\mathrm{A}} \left( \frac{ 1 }{ T_{\mathrm{ref}} } - \frac{ 1 }{ T ( \tau ) } \right) }\right) \tau$$ (12.16)

where c_A is the Arrhenius constant and T_ref a reference temperature.

    (syntax)

EQUAGE ARRTYP

applies calculation of the equivalent age according to the Arrhenius-type equation (12.16).

TEMREF

ter is the reference temperature T_ref in °C . [ T_ref = 20 ]

Arrhenius constant

specification [§12.5.4].

12.5.3.2 Saul Definition

Saul[91] defines the equivalent age according to

$$\int_{{0}}^{{t}} {\frac{{ T(\tau) - T_{0} }}{{ T_{\mathrm{ref}} - T_{0} }}} \tau$$ (12.17)

where T_ref is a reference temperature and T₀ is the datum temperature below which hydration ceases.

    (syntax)

EQUAGE SAUL

applies calculation of the equivalent age according to Saul (12.17).

TEMREF

ter is the reference temperature T_ref in °C . [ T_ref = 20 ]

DATUMT

te0 is the datum temperature T₀ in °C . By default DIANA assumes T₀ = - 10 °C , which applies for concrete. [ T₀ = - 10 ]