DULAY, Anthony Mark V. April 28, 2015 2012104035/ CE-3 Engr. Ronnie Dy Hianto Structure is a fundamental, tangible or intangible notion referring to the recognition, observation, nature, and permanence of patterns and relationships of entities. This notion may itself be an object, such as a built structure, or an attribute, such as the structure of society. It is an assemblage of a number of components like slabs, beams, columns, walls, foundations and so on, which remains in equilibrium. It has to satisfy the fundamental criteria of strength, stiffness, economy, durability and compatibility, for its existence. DIFFERENCE BETWEEN DETERMINATE AND INDETERMINATE STRUCTURES. Determinate structures are analyzed just by the use of basic equilibrium equations. By this analysis, the unknown reactions are found for the further determination of stresses. Redundant or indeterminate structures are not capable of being analyzed by mere use of basic equilibrium equations. Along with the basic equilibrium equations, some extra conditions are required to be used like compatibility conditions of deformations etc to get the unknown reactions for drawing bending moment and shear force diagrams. All the beams in which reactions of the supports may be determined by the use of equations of static equilibrium are known as statically determinate beams. The value of these reactions are independent of the deformation of the beam, while Indeterminate Structures is termed as statically indeterminate, if it cannot be analyzed from principles of statics alone, i.e. summation of forces horizontally, vertically and moments are equal to zero. A statically indeterminate structure may be classified as externally indeterminate, internally indeterminate and both externally and internally indeterminate. All the beams in which the number of reactions exceeds than the total number of equations of