Determinate and indeterminate structures« Back to Questions List
What is the difference between determinate and indeterminate structures?
Structural analysis involves solving determinate and indeterminate structures.

▲ ▼ 
Determinate structures are those which can be solved by using equations of equilibrium whereas indeterminate equations can not be solved by using only the equations of equilibrium. We need additional equations known as compatibility equations to solve indeterminate structures. 
▲ ▼ 
There are two types of Indeterminacy: Static and Kinematics. The degree of static indterminacy is the number of redundant forces or reactions that require extra equations than that of equilibrium condition to solve it.The number of extra equations is the degree of static redundancy of the structure. But, Kinematic redundancy is nithing but opposite to the static one i.e., it deals with degree of freedom of joints or nodes of a structure in any of direction of possible movement of that joints/nodes. as for example a twodimensionalsimply supported beam is statically determinate but kinematicaly indeterminate by 3rd degree. Visavis a fixed beam is statically indeterminate by 3rd degree but kinematically it is determinate. 
▲ ▼ 
Further to solve a structure means that we can determine external support reactions as well as internal actions i.e. bending moment, shear force, axial force and twisting moment as applicable. 
▲ ▼ 
yes 