Coastal and Floodplain Construction Inspector's Practice Exam

A diaphragm described as unblocked has which of the following characteristics?

1. Edge nailing at supporting members only

2. All edges blocked and nailed

3. Panel corners reinforced

4. Multiple layers of blocking

The correct answer is: Edge nailing at supporting members only

A diaphragm that is described as unblocked refers to a construction assembly where the edges where the panels meet at the supporting members do not use additional blocking for reinforcement. In this case, edge nailing at supporting members only is characteristic of an unblocked diaphragm. The term "unblocked" indicates that the seams of the panels are simply nailed to the edges of the supports without employing blocking materials between them. This design can still achieve adequate strength and performance in many cases because the nailing creates a direct connection to the supporting members, allowing the diaphragm to transmit loads effectively. In a structural context, these implications are significant, especially in how the diaphragm participates in resisting lateral forces, such as wind or seismic loads. Other characteristics, such as all edges being blocked and nailed, panel corners being reinforced, or using multiple layers of blocking, indicate a different structural assembly that enhances the stiffness and strength of the diaphragm, but these are not applicable to an unblocked configuration. It is important to understand the properties and implications of unblocked diaphragms, as they play a crucial role in the overall integrity and performance of constructions in coastal and floodplain areas.