Explanation:
The aggregate impact value (AIV) is a measure of the resistance of aggregate to sudden impact or shock, which is expressed as a percentage. It is determined by subjecting a specimen of aggregate to a standard impact test, and the resulting value indicates the toughness or hardness of the aggregate.

Types of Pavement:
There are various types of pavements used in civil engineering, including cement concrete base course, bitumen bound macadam base course, bituminous concrete surface course, and water bound macadam base course. Each type of pavement has different requirements and characteristics.

Aggregate Impact Value (AIV) Limit:
The aggregate impact value (AIV) is an important parameter to consider when selecting aggregates for different pavement courses. Generally, a lower AIV indicates a stronger and more durable aggregate.

Pavement Types and Aggregate Impact Value:
1. Cement Concrete Base Course:
- Cement concrete is a rigid pavement material that is used as a base course in highways and airfield pavements.
- It is designed to have high compressive strength and durability.
- The aggregate used in cement concrete should have a low AIV to ensure its strength and durability.
- Thus, aggregate with an AIV of 26% should not be used in cement concrete base course.

2. Bitumen Bound Macadam Base Course:
- Bitumen bound macadam is a type of flexible pavement material used in highways and roads.
- It consists of a mix of aggregate and bitumen binder.
- The aggregate used in bitumen bound macadam should have good strength and resistance to impact.
- Aggregate with an AIV of 26% can be suitable for bitumen bound macadam base course.

3. Bituminous Concrete Surface Course:
- Bituminous concrete, also known as asphalt concrete, is a type of flexible pavement material used in highways and roads.
- It consists of a mix of aggregate, bitumen binder, and filler materials.
- The aggregate used in bituminous concrete should have good strength, durability, and resistance to impact.
- Aggregate with an AIV of 26% should not be used in bituminous concrete surface course.

4. Water Bound Macadam Base Course:
- Water bound macadam is a type of flexible pavement material used in rural roads and low-traffic areas.
- It consists of a mix of coarse aggregates, screenings, and water.
- The aggregate used in water bound macadam should have good strength and resistance to impact.
- Aggregate with an AIV of 26% can be suitable for water bound macadam base course.

Conclusion:
In conclusion, aggregate with an AIV of 26% should not be used in bituminous concrete surface course. This is because the surface course requires higher strength, durability, and resistance to impact, which cannot be achieved with aggregate having a higher AIV.