Your Team has build a steering system using a CFRP steering column. It is bonded to the steering rack pinion shaft. During scrutineering you get told that a bonded connection is not allowed (T 2.6.10). In order to create the necessary mechanical connection you decide to add a shoulder bolt going through the necessary diameter of the shoulder bolt? Consider only one bolt and a required safety factor of 1.5 or higher. Allowed average contact pressure for the CFRP column is p_max=60MPa. Your steering column comes with an outer diameter of 25mm and an inner diameter of 20mm. The steering system is designed for a torque of 20Nm. Use the simplification of projected area for average contact pressure calcualtion p=F/(d*t) F:Force d:diameter of shoulder Bolt t:material thickness

1. 8mm
2. 10mmCorrect
3. 5mm
4. 6mm