Which two types of slabs are typically equipped with perimeter expansion joints?

The correct response identifies floating and supported slabs as the two types typically equipped with perimeter expansion joints, and understanding the characteristics of these slabs clarifies why this answer is appropriate.

Floating slabs are designed to move independently of the structures they are connected to, which means they require expansion joints to accommodate shifts due to thermal expansion and contraction. These joints help prevent cracking and structural damage by allowing the slab to expand and contract without being restrained.

Supported slabs, on the other hand, are generally anchored to a structure and experience similar thermal and moisture-related movements. The inclusion of expansion joints in supported slabs is vital, as they help manage these movements without compromising the integrity of the slab.

In contrast, the other types listed do not typically incorporate perimeter expansion joints in the same way. Reinforced and unreinforced slabs are generally categorized based on whether they have rebar or mesh for added tensile strength, but they do not specifically relate to the requirement for expansion joints. Concrete and asphalt do pertain to materials and might involve different considerations, but this terminology does not focus on the specific characteristics of slabs regarding movements. Wood and composite materials, while relevant in different contexts of construction, do not pertain to slab types that are commonly associated with expansion joints.

Thus, the focus