3 Critical Factors to Consider When Selecting Road Base Aggregate Material

5 July 2019
 Categories: Construction & Contractors, Blog


The base and sub-base of any road largely determine the road's ability to withstand the stresses of heavy loads as well as varying harsh weather conditions. For road construction contractors, therefore, getting the basics right is critical to the construction of a durable and robust road. As such, your choice of aggregate material must be of the best quality, or you will find yourself dealing with premature road damage and deterioration. When sourcing road base supplies, ensure that you consider the factors highlighted in this article. Not only will you complete the project on time, but you will also save on repair costs that come with premature road deterioration. 

Particle Angularity 

For a road to last long under constant stresses, the aggregate material must withstand forces placed upon it by vehicles. The only way this is possible is to use aggregate with particles that are either cubical or angular. It is because the sharper the edges of the aggregate material are, the more resistance is provided under traffic loads. Aggregates with rounded, smooth surface surfaces tend to roll out under increased and sustained traffic loads. Consequently, the road surface will start to deform, which is why you find some roads with sunken sections. Highly angular aggregate particles have numerous contact points, and this creates more friction between particles for a more resilient road base. 

Aggregate Moisture Content

If you are looking for road base material that is 100% moisture-free, then you will not find any. It is because moisture can be found in just about anything, and the only difference is the level of moisture content. Therefore, it is vital to select base materials that meet the recommended maximum dry density values for road construction. Any aggregate materials that have a lower value are deemed unsuitable for road projects. For instance, top soil with clay content will not do well as a road sub-base material since it is susceptible to deformation under traffic loads.

Access Road Use

Different roads have different uses; therefore, before you begin any road construction project, it is essential first to find out how the road will be used. The primary question you should ask here is the type of vehicles that will be using the way. For instance, roads leading to residential estates are mostly used by light vehicles, the heaviest of which being SUVs. For such a project, the width and depth of the road will not be as substantial as roads that are exclusively meant for heavy-duty vehicles. The amount of aggregate material used will, therefore, be less. On the other hand, since roads constructed only for trucks require a deep base material, the amount of aggregate material required is more.