Fundamentals of prestressed concrete: A prestressed concrete member is best described as which of the following?

Introduction / Context:
Prestressed concrete (PSC) is a structural material in which internal stresses are deliberately introduced to counteract tensile stresses produced by service loads. This enables slimmer, longer spans with reduced cracking and deflection compared to ordinary RC.

Given Data / Assumptions:

• Member is a concrete element with high-strength steel tendons.
• Stressing may be pre-tensioning or post-tensioning.

Concept / Approach:
The defining characteristic of PSC is the presence of initial internal compressive stress in concrete caused by tensioned steel. Whether the stressing is before (pre-tensioning) or after (post-tensioning) casting, the key feature is the engineered internal stress state, not merely the material type.

Step-by-Step Explanation:
Tendons are tensioned relative to the concrete.Anchorage/bond transfers this force, compressing the concrete.Service tensile stresses are reduced or eliminated, improving crack control and deflection.

Verification / Alternative check:
Pre-tensioned pretensioning beds and post-tensioned ducts both create internal compressive stress; this shared outcome distinguishes PSC from ordinary RC.

Why Other Options Are Wrong:
is made of concrete / is made of reinforced concrete: Too generic; RC can exist without prestress.is stressed after casting: Only post-tensioning; PSC also includes pre-tensioning.is free of any initial stress: Opposite of PSC definition.

Common Pitfalls:

• Confusing PSC with high-strength RC without deliberate prestress.
• Thinking only post-tensioned systems count as PSC.

Final Answer:
possesses internal stresses