21.3.2 Power Law (Noakowski)

The relationship between shear traction and slip proposed by Noakowski [80] models a kind of stick-slip behavior [Fig.21.14].

Figure 21.14: Power Law for bond-slip (Noakowski)

The initial shear stiffness is kept linear to avoid an unrealistically high stiffness when the slip is smaller than an initial value $\Delta$u_t⁰ . This relation is formulated with a Power Law:

$$\begin{cases} a \left( \,\mathrm{d}t\right)^{b} \hspace*{12e... ...\text{if $0 \leq \,\mathrm{d}t< \,\mathrm{d}t^{0}$} \end{cases}$$ (21.24)

with b < 1 . Unloading and reloading is modeled with a secant approach.