What is the guideline for calculating the expansion joint spacing for a concrete walkway?

The guideline for calculating the expansion joint spacing in a concrete walkway is based on the width of the walkway. Specifically, the recommended spacing is typically 2 times the width of the walkway. This is important for accommodating the natural expansion and contraction of concrete due to temperature changes and moisture levels, preventing cracking and damage.

In wider walkways, the 2x width guideline ensures that the joints are spaced sufficiently to allow for movement without compromising the structural integrity of the concrete. When the spacing exceeds this guideline, there is a greater risk of cracking, as the concrete may not be able to expand or contract adequately. Therefore, adhering to this guideline helps in effectively managing the stresses placed on the concrete, which is why the correct answer reflects this relationship.