Which is the best definition of the unit load method?

• Sometimes referred as the Unit-Load Method • Generally provides of obtaining the displacement and slope at a specific point on structure i.e. beam, frame or truss • In general, the principle states that: P u Work of External Loads Work of Internal Loads by Saffuan Wan Ahmad Principle of Virtual Work (Displacement)

What causes the deflection of a truss beam?

Answer:  The deformations or movements of a structure and its components, such as beam ends, truss joints etc., from their original positions/location.  Deflection is caused by many sources, such as, loads, temperature, construction error, and settlements.

Why is computation of deflection of structures necessary?

Computation of deflection of structures is necessary for the following reasons:  a. If the deflection of a structure is more than the permissible, the structure will not look aesthetic and will cause psychological upsetting of the occupants.  b. Excessive deflection may cause cracking in the materials attached to the structure.

How to create a virtual system for deflection?

The number of expressions will be governed by the number of cuts that are needed to solve the structure. Step 3: Create a virtual system by removing all forces acting on the beam, and applying a unit load to find the expression for deflection, and a unit moment to find an expression for slope. Repeat step 2 for the virtual system.

How is the force method used in structural analysis?

Analysis of Statically Indeterminate Structures by the Force Method (Flexibility Method or Method of Consistent Deformation) 1.1 Basic Concepts of the Force Method The force method (which is also called the flexibility method or the method of consistent deformations) uses the concept of structural Static Indeterminacy (SI).

How is slope deflection used in beam and frame structures?

In the second chapter, concepts of slope-deflection method are developed and applied to beam and frame structures. The third chapter deals with developments of concepts of the moment distribution method. These concepts are then applied to beam and frame structures.

How is displacement determined by a virtual load?

Principle of Virtual Work (Displacement) • Since no external load acts on the body at A and in the direction of the displacement , the displacement can be determined by first placing on the body a “virtual” load suc that this force P’ acts in the same direction as , (see Figure) by Saffuan Wan Ahmad