Which type of joint helps manage cracking in concrete slabs due to shrinkage?

The correct answer is a control joint. Control joints are specifically designed in concrete slabs to manage cracking that occurs as a result of shrinkage. When concrete is poured and begins to cure, it can experience a reduction in volume as moisture evaporates, leading to tension that may cause cracks. Control joints are introduced at predetermined locations to create weak points in the slab where cracks can occur rhythmically, rather than in random places. This strategic placement helps to control where cracks form, allowing for a more aesthetically pleasing surface and preventing unintended damage.

Expansion joints are utilized to accommodate the expansion and contraction of materials due to temperature changes, rather than managing shrinkage cracks. Tapered or beveled joints are not typically used in managing cracking; they are often related to the finishing techniques or aesthetics of concrete edges. Butt joints are simply where two pieces of concrete meet but do not offer any specific benefits for managing shrinkage or cracking.