Question

Discuss the theories behind the following methods of structural analysis. Use appropriate diagrams.

1. Elastic analysis second order
2. Finite element analysis analysis

Answer 1

2)

To understand Finite element analysis easily, let's take a realistic problem from transportation engineering, i.e, accident analysis. see, these insurance companies need to know the impact of the accident to refund the amount, for this they need to perform accidents via some toys or plastic men shaped toys. but it is like wasting more money on analysis. So here we come with a tool called finite element analysis. What this tool does is tools are, this tool has finite elements of all basic material like wood, steel, aluminum, etc with their natural properties i.e strength, toughness, etc. these materials are finite (small), & in the shape of a rectangle, triangle, square, pyramid, circle, etc. let's suppose, if we want to test car, the car is made with these materials (with which car is made in reality) easily. if that car met with an accident to iron poll, then the iron poll is made in the software (by assembling iron of finite elements ), so that by performing little operations, the impact of the accident is calculated rather than performing it physically. these finite elements of different materials are known as mesh in software terminology. this is what simple application of finite element to understand easily.

1)

The second-order analysis is also known as P- (P-delta) analysis. It's used only when deformations are high or if lateral sway gives considerable secondary moments the P- (P-delta) analysis is used.

generally for long columns or tall structures, lateral loads may be wind plays a crucial role which leads to lateral deformation (i.e deformation in the horizontal direction) but structural loads mean live load, dead load acts vertically, So these horizontal as well vertical cause secondary moments, so if secondary moments are considerably high, then P- (P-delta) analysis is used.