1 Member Truss
There are three broad categories of engineering structures will be considered:
1. Trusses, which are designed to support loads and are usually stationary, fully constrained structures. Trusses consist exclusively of straight members connected at joints located at the ends of each member. Members of a truss, therefore, are two- force members, i.e., members acted upon by two equal and opposite forces directed along the member.
2. Frames, which are also designed to support loads and are also usually stationary, fully constrained structures. However, like the crane, frames always contain at least one multiforce member, i.e., a member acted upon by three or more forces which, in general, are not directed along the member.
3. Machines, which are designed to transmit and modify forces and are structures containing moving parts. Machines, like frames, always contain at least one multiforce member.
The truss is one of the major types of engineering structures. It provides both a practical and an economical solution to many engineering situations, especially in the design of bridges and buildings. The equation for perfect truss is m = 2j-3.
Types of truss:
- Perfect truss: - truss having perfect number of members to become a statically determinate structure is called perfect truss (m = 2j-3).
- Imperfect truss: - truss having imperfect number of members. It is of two types:
(a) Deficient truss: - truss having less number of members than required is called deficient truss
(m < 2j-3).
(b) Redundant truss: - truss having more number of members than required is called redundant truss (m > 2j-3).