**Angular Shaped**

Aggregates are commonly used in construction materials such as concrete and asphalt. They are typically composed of crushed stone, gravel, or sand. The properties of aggregates play a crucial role in determining the strength, durability, and workability of the final construction material. Among the properties of aggregates, the angular shape is considered undesirable. Here's why:

**1. Interlocking and Bonding:**
Smooth aggregates tend to interlock and bond well with each other, creating a stronger and more stable structure. The smooth texture allows for better contact and adhesion between the aggregates, leading to improved load-bearing capacity. In contrast, angular aggregates have less contact area, resulting in reduced interlocking and bonding.

**2. Workability:**
Workability refers to the ease of handling and placing the concrete or asphalt mix. Smooth aggregates provide a more workable mixture as they can slide past each other easily, allowing for better compaction and shaping. On the other hand, angular aggregates tend to have more friction between particles, making the mixture less workable and more difficult to handle.

**3. Surface Abrasion:**
During transportation and placement of aggregates, they can undergo abrasion due to rubbing against each other or other surfaces. Smooth aggregates are less prone to surface abrasion since there are no sharp edges or corners that can break off. Angular aggregates, however, have sharp edges that are more susceptible to abrasion, leading to a loss of material and potential weakening of the overall structure.

**4. Water Demand:**
Water demand is an important consideration in the design of concrete. Smooth aggregates require less water to achieve the desired workability compared to angular aggregates. This is because the smooth texture allows for better lubrication and flow of water within the mixture. Angular aggregates, on the other hand, have more surface area and can absorb more water, increasing the water demand and potentially affecting the overall strength and durability of the concrete.

In conclusion, the angular shape of aggregates is considered undesirable due to its negative effects on interlocking, bonding, workability, surface abrasion, and water demand. Smooth aggregates are preferred in construction materials to ensure a stronger, more durable, and easier-to-handle final product.