Understanding Structural Members Under Tensile Force

A structural member is a component in a structure designed to withstand loads. These members can be subjected to various types of forces, including compression (pushing) and tension (pulling). The question asks about a structural member that experiences a tensile force acting parallel to its longitudinal axis.

Let's break down the terms provided in the options:

• Tie: In structural engineering, a "tie" is specifically defined as a structural member designed to resist tensile forces. Ties are often used to connect different parts of a structure and prevent them from spreading apart under load.
• Tie Member: This is essentially another way of saying "tie." It explicitly states that the member is a "tie," which by definition resists tension. So, a tie member is a structural member subjected to tensile force.
• Tension Member: This term directly describes the function of the member – it is a member designed to carry tension. It is a general term for any structural component subjected predominantly to axial tensile stress.

Consider a simple truss structure. The diagonal or horizontal members that are under a pulling force are referred to as tension members or ties.

Based on the definitions, all three terms – "a tie", "a tie member", and "a tension member" – refer to a structural element that is designed or subjected to withstand a tensile force acting along its length (longitudinal axis). Therefore, all the given options are correct descriptions of such a member.

Analysis of Options

Let's look at why each option is valid in the context of the question:

• Option 1: a tie - This is a standard term for a member resisting tension.
• Option 2: a tie member - This term explicitly identifies it as a member functioning as a tie, i.e., resisting tension.
• Option 3: a tension member - This term directly states that the member carries tension.
• Option 4: All option are correct - Since options 1, 2, and 3 all correctly describe a structural member subjected to tensile force, this option is the most accurate choice.

In practice, these terms are often used interchangeably when referring to members that are primarily loaded in tension.

Conclusion on Structural Member Terminology

The question asks for the name of a structural member under tensile force parallel to its longitudinal axis. Common engineering terminology refers to such members as ties, tie members, or tension members. All three terms accurately describe the function and loading condition of the member.

Revision Table: Key Terms for Structural Members

Understanding the common terms for structural components based on the forces they resist is fundamental.

• Tension Member (Tie): Resists pulling forces (tension).
• Compression Member (Strut, Column): Resists pushing forces (compression).
• Beam: Resists bending forces.
• Slab: Resists bending forces over an area.

Additional Information: Importance of Identifying Member Types

Correctly identifying whether a structural member is under tension or compression is crucial in structural design. Different materials behave differently under tension and compression (e.g., concrete is strong in compression but weak in tension, while steel is strong in both). The design calculations, material selection, and connection details depend heavily on whether a member is a tension member or a compression member. For example, tension members are generally designed to prevent yielding or rupture, while compression members must also be checked for buckling instability.