Normal stress in tangential direction at wellbore wall (hoop stress)

Input(s)

Shmax: Maximum Principal Stress in reservoir (psi)

Shmin: Minimum Principal Stress in reservoir (psi)

Po: Pore Pressure (psi)

$S d t$: Stress induced due to temperature (psi)

$d P$: Difference between Wellbore Pressure and Mud Weight (psi)

$\theta$: Angle from $S_{\text {hmax }}$ at which stress is measured (degrees)

Output(s)

sig $_{\text {th }}$: Hoop Stress in Tangential Direction at Wellbore Wall (psi)

Formula(s)

$$ \operatorname{sig}_{\mathrm{th}}=(\operatorname{Shmax}+\mathrm{Shmin})-2 *(\text { Shmax }-\operatorname{Shmin}) * \cos \left(2 * \theta * \frac{3.142}{180}\right)-2 * \text { Po }-\mathrm{dP}-\mathrm{Sdt} $$

Reference(s)

Mark D. Zoback, Reservoir Geomechanics, Cambridge University Press, UK, Page: 102.