A multi force member in statics is a structural element that is subjected to multiple forces at various points along its length. These forces can be either external forces acting on the member or internal forces resulting from the reaction to external forces on the member.
Multi force members are important to consider in statics because they can affect the stability and strength of a structure. Neglecting to account for these forces can result in structural failure or inaccuracies in calculations.
The internal forces of a multi force member can be calculated using the method of sections. This involves isolating a section of the member and analyzing the external and internal forces acting on that section to determine the internal forces.
A statically determinate multi force member is one in which the internal forces can be determined solely by using equations of static equilibrium. An indeterminate multi force member, on the other hand, requires additional information or equations to solve for the internal forces.
Yes, a multi force member can have multiple points of zero internal force. These points are known as points of contraflexure, and they occur when the internal bending moment changes direction along the length of the member.