North Carolina Building Contractor License Practice Exam

How is reverse curvature addressed in post-tensioned concrete?

1. By placing additional bars

2. 80 inches

3. 96 days

4. 1:12 ratio

The correct answer is: 80 inches

The concept of reverse curvature in post-tensioned concrete refers to the situation where tension forces in the tendons create a curvature opposite to what is typically expected in a simply supported beam. This can lead to significant stress concentrations and potential structural issues if not addressed properly. In the context of post-tensioned concrete, managing reverse curvature often involves precise calculations regarding the tensioning of the cables, the layout of the tendons, and the design of the concrete elements themselves. The effective spacing and tensioning strategies are critical in ensuring that the resulting stresses are distributed effectively across the structure, preventing issues such as cracking and bending. The number '80 inches' as a response is indicative of a specific measurement or guideline related to the spacing or configuration of post-tensioning systems to manage these reverse curvature effects effectively. It may represent a maximum allowable distance for the tendons or a specific dimension in a design standard that ensures adequate performance while addressing the stresses created by reverse curvature. Understanding this measurement allows builders and engineers to create safe and effective designs in post-tensioned concrete applications where reverse curvature could pose a challenge. Other answers may suggest different aspects of construction or design terms that do not directly relate to the management of reverse curvature in terms of specific measurements or