NCIDQ IDFX Practice Exam

What are lateral loads primarily caused by?

1. People and furniture

2. Vertical loads from permanent structures

3. Wind and earthquake forces

4. Sudden dynamic forces

The correct answer is: Wind and earthquake forces

Lateral loads are primarily the forces that act horizontally on a structure. These forces are chiefly caused by natural phenomena such as wind and earthquakes, which create significant pressure across the surfaces of buildings and other structures. When wind blows against a building, it pushes against the walls, generating lateral forces that can lead to swaying or even structural failure if not properly accounted for in design. In the case of earthquakes, the ground motion can cause buildings to move sideways, leading to lateral forces that can similarly jeopardize structural integrity. The structural design must include considerations for these lateral loads to ensure stability and safety, making it critical for architects and designers to understand how to address these forces in their plans. While people and furniture can exert loads on a structure, these are primarily vertical loads rather than lateral. Vertical loads come from the weight of the structure itself and anything that is permanently attached or placed within it. Sudden dynamic forces may also contribute to lateral loads, but they are not the primary cause, as wind and seismic activity represent the most common sources of lateral forces that designers must consider.